oulu 2016 d 1359 university of oulu p.o. box 8000 fi...

UNIVERSITY OF OULU P .O. Box 8000 F I -90014 UNIVERSITY OF OULU FINLAND

A C T A U N I V E R S I T A T I S O U L U E N S I S

Professor Esa Hohtola

University Lecturer Santeri Palviainen

Postdoctoral research fellow Sanna Taskila

Professor Olli Vuolteenaho

University Lecturer Veli-Matti Ulvinen

Director Sinikka Eskelinen

Professor Jari Juga

University Lecturer Anu Soikkeli


Publications Editor Kirsti Nurkkala

ISBN 978-952-62-1197-8 (Paperback)ISBN 978-952-62-1198-5 (PDF)ISSN 0355-3221 (Print)ISSN 1796-2234 (Online)

U N I V E R S I TAT I S O U L U E N S I S

MEDICA

ACTAD

D 1359

ACTA

Iikka Lantto

OULU 2016

D 1359

Iikka Lantto

ACUTE ACHILLES TENDON RUPTUREEPIDEMIOLOGY AND TREATMENT

UNIVERSITY OF OULU GRADUATE SCHOOL;UNIVERSITY OF OULU,FACULTY OF MEDICINE;MEDICAL RESEARCH CENTER OULU;OULU UNIVERSITY HOSPITAL

A C T A U N I V E R S I T A T I S O U L U E N S I SD M e d i c a 1 3 5 9

IIKKA LANTTO

ACUTE ACHILLES TENDON RUPTUREEpidemiology and treatment

Academic Dissertation to be presented with the assent ofthe Doctora l Train ing Committee of Health andBiosciences of the University of Oulu for public defence inAuditorium 1 of Oulu University Hospital, on 13 May2016, at 12 noon

UNIVERSITY OF OULU, OULU 2016

Copyright © 2016Acta Univ. Oul. D 1359, 2016

Supervised byProfessor Juhana LeppilahtiDocent Tapio Flinkkilä

Reviewed byProfessor Teppo JärvinenDocent Minna Laitinen

ISBN 978-952-62-1197-8 (Paperback)ISBN 978-952-62-1198-5 (PDF)

ISSN 0355-3221 (Printed)ISSN 1796-2234 (Online)

Cover DesignRaimo Ahonen

JUVENES PRINTTAMPERE 2016

OpponentProfessor Heikki Kröger

Lantto, Iikka, Acute Achilles tendon rupture. Epidemiology and treatmentUniversity of Oulu Graduate School; University of Oulu, Faculty of Medicine; MedicalResearch Center Oulu; Oulu University HospitalActa Univ. Oul. D 1359, 2016University of Oulu, P.O. Box 8000, FI-90014 University of Oulu, Finland

Abstract

The Achilles tendon is the strongest and largest of human tendons, and its proper function isessential for normal gait. Most acute Achilles tendon injuries occur during sports, particularly inball games.

The purposes of this study were (1) to examine the incidence of total Achilles tendon rupture(ATR) over a 33-year period in the city of Oulu and to investigate its changes with respect to age,sex, and injury mechanism. (2) to compare ≥10-year outcomes of two postoperative regimens afterATR repair: early weightbearing with early mobilization versus early weightbearing with earlyimmobilization in tension, (3) to compare clinical outcome and calf muscle strength recovery afterconservative treatment or open surgical repair of acute ATR, followed by identical acceleratedrehabilitation programs.

The overall incidence per 100 000 person years increased from 2.1 in 1979 to 21.5 in 2011. Theincidence increased in all age groups. The incidence of sports-related ruptures increased duringthe second 11-year period, whereas the incidence of non-sports-related ruptures increased steadilyover the entire study period.

Early mobilization and immobilization in tension after ATR repair resulted in similar clinicaloutcomes and isokinetic strengths. Regardless of patient satisfaction with the operative treatment,calf muscle strength did not recover normally, even at the 10-year follow-up.

Surgery and conservative treatment of acute ATR resulted in similar Achilles tendonperformance score after 18 months, but surgery restored calf muscle strength earlier. Surgery alsoresulted in better health-related quality of life in the domains of physical functioning and bodilypain. Conservative treatment with a functional protocol is recommended for a large majority ofpatients. However, patients with high physical expectations could still benefit from operativetreatment.

In conclusion, the incidence of ATR is rising, postoperative immobilization and earlymobilization result in similar long-term results in terms of the Achilles tendon performance scoreand calf muscle function, and conservative treatment with a functional protocol is the preferredtreatment for the majority of patients.

Keywords: achilles tendon rupture, conservative treatment, epidemiology, long-termresult, operative treatment

Lantto, Iikka, Akuutti akillesjänteen repeämä. Esiintyvyys ja hoitoOulun yliopiston tutkijakoulu; Oulun yliopisto, Lääketieteellinen tiedekunta; Medical ResearchCenter Oulu; Oulun yliopistollinen sairaalaActa Univ. Oul. D 1359, 2016Oulun yliopisto, PL 8000, 90014 Oulun yliopisto

Tiivistelmä

Akillesjänne on ihmisen suurin ja vahvin jänne ja sen kunnollinen toiminta on edellytys normaa-lille kävelylle. Suurin osa akillesjänteen repeämistä syntyy urheilussa, erityisesti pallopeleissä.

Ensimmäisessä osatyössä oli tarkoitus selvittää täydellisten akillesjänteen repeämien esiinty-vyys Oulussa 33 vuoden aikana ja selvittää potilaiden ikä ja sukupuoli sekä vammamekanismi.Toisessa osatyössä vertailtiin akillesjänteen repeämän hoitotuloksia 11 vuotta vamman jälkeen.Tässä tutkimuksessa verrattiin kahta erilaista leikkauksen jälkeistä hoitomenetelmää; toisessasallittiin varhainen varaaminen ja nilkan liikuttelu kun taas toisessa sallittiin varhainen varaami-nen, mutta nilkka kipsattiin ojennukseen. Kolmannessa osatyössä vertailtiin tuloksia leikattujenja ilman leikkausta hoidettujen potilaiden välillä. Molemmat ryhmät hoidettiin samanlaisellairrotettavalla varaamisen sallivalla lastalla.

Akillesjänteen repeämien esiintyvyys oli 2.1/100 000 vuonna 1979 ja nousi vuoteen 2011mennessä 21.5/100 000:een ja nousua oli kaikissa ikäryhmissä. Urheiluun liittyvät repeämätlisääntyivät erityisesti jakson keskimmäisen 11-vuotis jakson aikana kun taas urheiluun liitty-mättömät repeämät lisääntyivät koko seurantajakson ajan.

Vertailtaessa kahta erilaista leikkauksen jälkeistä hoitomenetelmää todettiin ettei potilaidenvälillä ollut eroa kliinisissä mittareissa tai voimissa 11 vuotta vamman jälkeen. Vaikka potilas-tyytyväisyys oli hyvä ei pohkeen voima palautunut normaaliksi edes 11 vuotta vamman jälkeen.

Vertailtaessa leikkauksella ja ilman leikkausta hoidettuja potilaita ei myöskään todettu erojakliinisissä mittareissa, mutta kirurgisella hoidolla voima palautui hiukan nopeammin ja ero myössäilyi 18 kuukautta vammasta. Myös elämänlaatumittarilla mitattuna leikkauksella hoidetut oli-vat kivun ja fyysisen toiminnan osalta tyytyväisempiä. Suurimmalle osalle potilaista konservatii-vinen hoito sopii erinomaisesti, mutta jotkut fyysisesti aktiiviset potilaat hyötynevät leikkaushoi-dosta.

Asiasanat: akillesjänteen repeämä, epidemiologia, konservatiivinen hoito, operatiivinenhoito, pitkäaikaistulokset

To my family

9

Acknowledgments

This study was carried out at the Department of Surgery, University of Oulu,

during the years 2009 to 2015.

I am much obliged to a lot of persons who helped and trusted me during this

process.

I wish to express my sincere gratitude to my supervisor, Professor Juhana

Leppilahti M.D., Ph.D. Head of the Division of Orthopaedic surgery. He

originally encouraged me to start this work and used his exceptional knowledge

about Achilles tendon research to help this work completed. I also owe my

warmest thanks to my second supervisor Docent Tapio Flinkkilä M.D. Ph.D for

his patient guidance and support. I really admire his passionate attitude towards

scientific research including clinical work, too.

I also owe my gratitude to Docent Kari Haukipuro M.D., Ph.D., Head of the

Division of Operative Care, and Susanna Yliluukko MD., Head of Department of

Neurosurgery, Orthopaedics and Traumatology, for the opportunity to work and

do research in the Department of Surgery. Additionally, my deepest thanks to

Professor Tatu Juvonen, M.D., Ph.D. for his support during this work.

I am truly grateful to my co-author Juuso Heikkinen M.D. His enthusiastic

and hardworking attitude has pushed me forward with these studies.

I wish to thank Olli Savola M.D. Ph.D. for keeping this study project alive

during times when it was not possible on my own.

I am also grateful to thank Pasi Ohtonen M.Sc. for his statistical assistance

and patient help to improve my understanding concerning biostatistics and Jarmo

Kangas MD., PhD. Pertti Siira PT and Vesa Laine M.Sc for their collaboration as

co-authors.

I warmly thank Docent Minna Laitinen M.D. Ph.D. and Professor Teppo

Järvinen M.D. Ph.D the official reviewers of this thesis for their valuable

comments and constructive criticism.

Docent Jukka Ristiniemi M.D. Ph.D., Docent Pekka Hyvönen MD. Ph.D.,

Harri Pakarinen MD. Ph.D. I am most indebted to you for sharing your great

experience of clinical skills and knowledge.

I want to thank all of my colleagues in our clinic and especially Jaakko Rönty

M.D., Tero Kortekangas M.D., Simo Nortunen M.D. and Hannu-Ville Leskelä

MD.Ph.D. for their encouraging attitudes and long scientific discussions in

Välikanslia.

10

I would also like to thank my friends Samppa and Nannu Lepojärvi for their

continuous support since the first day of my career in medicine.

I am deeply thankful to my parents Pirkko and Risto, my sister Kaisa and

brother Jouni for their love and encouragement throughout my life.

Finally, I express my deepest and loving thanks to Ulla, Eeli and Aatos for all

really important things in my life.

This study was financially supported by the Research Foundation for

Orthopaedics and Traumatology, the Finnish Medical Society Duodecim, the

Finnish Sport Research Foundation, Oulu University Hospital and Oulu

University.

Oulu, May 2016 Iikka Lantto

11

Abbreviations

AOFAS American Orthopedic Foot and Ankle Society

AT Achilles tendon

ATR Achilles tendon rupture

ATRS The Achilles tendon rupture score

BMI Body mass index

EMG Electromyography

HRQoL Health-related quality of life

MRI Magnetic resonance imaging

PT Peak torque

RCT Randomized controlled trial

ROM Range-of-motion

SF-36 36-item short form health questionnaire

US Ultrasonographic examination

13

List of original publications

This thesis is based on the following publications, which are referred throughout

the text by their Roman numerals:

I Lantto I, Heikkinen J, Flinkkilä T, Ohtonen P, Leppilahti J (2014) Epidemiology of Achilles tendon ruptures: increasing incidence over a 33-year period. Scand J Med Sci Sports. 25(1):e133–8.

II Lantto I, Heikkinen J, Flinkkilä T, Ohtonen P, Kangas J, Siira P, Leppilahti J (2015) Early Functional Treatment Versus Cast Immobilization in Tension After Achilles Rupture Repair: Results of a Prospective Randomized Trial With 10 or More Years of Follow-up. Am J Sports Med. Sep;43(9):2302–9

III Lantto I, Heikkinen J, Flinkkilä T, Ohtonen P, Siira P, Laine V, Leppilahti J (2015) A prospective randomized trial comparing surgery and conservative treatment in acute Achilles tendon ruptures. Surgery restores strength better, subjective results similar. Am J Sports Med, in press.

15

Contents

Abstract

Tiivistelmä

Acknowledgments 9

Abbreviations 11

List of original publications 13

Contents 15

1 Introduction 17

2 Review of the literature 19

2.1 Anatomy and biomechanics of the Achilles tendon ................................ 19

2.2 Acute ATR ............................................................................................... 21

2.2.1 Diagnosis ...................................................................................... 21

2.2.2 Epidemiology ............................................................................... 23

2.3 Treatment of acute ATR .......................................................................... 24

2.3.1 Conservative treatment ................................................................. 25

2.3.2 Operative treatment ...................................................................... 26

2.3.3 High-quality evidence of operative vs. conservative

treatment ....................................................................................... 27

2.4 Long-term results of acute Achilles tendon ruptures ............................... 31

3 Aims of the present study 33

4 Materials and methods 35

4.1 Epidemiology (I) ..................................................................................... 35

4.2 Long-term results of early functional treatment versus cast

immobilization in tension after ATR repair (II) ...................................... 35

4.2.1 Postoperative management ........................................................... 36

4.2.2 Outcome Measures ....................................................................... 37

4.3 RCT comparing surgery with conservative treatment (III) ..................... 38

4.3.1 Conservative Treatment ................................................................ 39

4.3.2 Surgical Treatment ........................................................................ 40

4.3.3 Outcome Measures ....................................................................... 40

4.4 Ethics (I, II, III) ....................................................................................... 40

4.5 Statistical methods (I, II, III) ................................................................... 41

5 Results 43

5.1 Epidemiology (I) ..................................................................................... 43

5.2 Early functional treatment (group 1) versus cast immobilization

(group 2) after ATR repair (II) ................................................................ 47

16

5.2.1 Leppilahti Score ............................................................................ 47

5.2.2 Isokinetic and isometric calf muscle strength ............................... 48

5.2.3 Complications / Re-operations ..................................................... 50

5.3 A prospective randomized trial comparing surgery and

conservative treatment (III) ..................................................................... 50

5.3.1 Leppilahti score ............................................................................ 50

5.3.2 Isokinetic calf muscle strength ..................................................... 51

5.3.3 RAND 36-Item health survey ....................................................... 52

5.3.4 Age ............................................................................................... 53

5.3.5 Complications ............................................................................... 53

6 Discussion 55

6.1 General considerations ............................................................................ 55

6.2 Epidemiology (I) ..................................................................................... 56

6.3 Early functional treatment versus cast immobilization in tension

after ATR repair (II) ................................................................................ 57

6.4 RCT comparing surgery and conservative treatment in acute

ATRs (III) ................................................................................................ 59

6.5 Clinical implications and future studies .................................................. 61

7 Conclusion 63

References 65

Appendices 77

Original publications 85

17

1 Introduction

The “poster child” for an acute Achilles tendon rupture (ATR) injury is the

approximately 40-year-old “weekend warrior” who participates in a sports

activity in his spare time. He will feel like somebody has kicked his Achilles

tendon (AT) when he reaches for the ball. He will feel that his ankle is not

working properly, and a palpable gap may be present in his AT at about 4 cm

above the heel bone. Diagnosis can usually be made clinically and is easily

confirmed by ultrasound (US).

The first report of an occurrence of ATR was by Christensen, who reported 57

ATRs among 70 000 patients treated in an orthopedic department between the

years 1936 and 1954 (Christensen 1954). Nillius et al. (1976) reported increasing

incidence of ATRs from Malmö, Sweden from 1950 to 1973. Since then, growing

evidence has confirmed that the ATR has become a more common tendon rupture

(Ganestam et al. 2015, Leppilahti et al. 1996). This is probably because

Scandinavian countries have publicly funded health care systems and reliable

medical records, so we have played a leading role in epidemiological studies

concerning ATRs. Previously published data from Oulu showed that the incidence

of ATRs in our city with about 200 000 inhabitants increased from 2/100 00 to

18/100 000 between years 1979 and 1994 (Leppilahti et al. 1996). This paper is

commonly cited in the international literature as an example of growing

incidence. Little is known of the changes in epidemiology that have occurred

during the last two decades.

At the same time as this increase in the number of patients suffering ATRs,

the discussion of optimal ATR treatment continues. In the first decades of the

1900s, the general development of surgical techniques improved the results of

operative treatment of ATRs. Even though some studies reported good outcomes

for nonoperative treatment and some papers reported severe surgery-related

complications, operative treatment became established as the gold standard,

especially in physically active patients, during 80s and 90s. Most commonly, an

ATR is operated on by a simple, open end-to-end operation, which can be

strengthened by one or two fascia flaps. The recent literature has not shown

advantages of performing fascia augmentation in short-term follow-up (Pajala et

al. 2009), and any advantages of minimally invasive techniques are also unclear

(Khan et al. 2005). Postoperative treatment has gradually changed from

prolonged cast immobilization into functional bracing procedures that allow early

weight bearing.

18

Historically, nonoperative treatment has included different kind of bandages

or casts for varying periods, normally between 6 and 9 weeks. In the beginning of

the 20th century, the famous American physician Dr. C.H. Mayo treated his own

ATR by putting a large cork under his shoe heel, and the injury healed in three

months (Lipscomb & Weiner 1956). Functional treatment protocols are becoming

more common as well in current nonoperative treatments. Modern functional

protocols have decreased the re-rupture, and most studies show functional

outcomes that are comparable to operative treatments (Soroceanu et al. 2012).

Nonoperative treatments avoid surgery-related complications, and their good

patient satisfaction and functional outcomes have made nonoperative treatments

the most preferred treatment type for ATRs, at least in Scandinavian countries

(Ganestam et al. 2015, Huttunen et al. 2014, Mattila et al. 2013,). However,

despite numerous prospective randomized trials comparing surgery with

nonoperative treatment, several issues, especially the recovery of calf muscle

strength and long-term results, remain unaddressed.

The main goal of the present study is to compare the results of surgery to

those of conservative treatment for ATRs, and to assess the long-term outcomes of

surgically treated patients. We also wanted to determine if the ATR incidence has

continued to increase in Oulu since 1994.

19

2 Review of the literature

2.1 Anatomy and biomechanics of the Achilles tendon

The AT consists of the tendons of the gastrocnemius and soleus muscles. The

purpose of the AT is to transmit the power of these muscles to the heel bone and

to produce knee flexion, tibiotalar flexion, and subtalar inversion. The length of

the AT fibers varies from 11–26 cm in the gastrocnemius part and from 3–11 cm

in fibers from soleus (Cummins et al. 1946). The cross sectional area of the AT

varies from 0.8 cm2 to 1.4 cm2 along the course of the tendon (O’Brien 1992) and

depends on the cumulative training load (Rosager et al. 2002). The biomechanical

loading in the AT can increase to 9 kN during running (Komi et al. 1992), and the

tensile strength of the tendon is about 50 N/mm in vitro (Jozsa & Kannus 1997),

which makes the normal tendon theoretically capable of supporting weights up to

1000 kg. The AT is the therefore the largest and the strongest of the human

tendons.

The AT is circular in shape at its midpoint, and it is wider at the

osteotendinous junction on the heel bone. The tendon fibers turn rotationally so

that those fibers from posterior gastrocnemius rotate anterolateral, whereas the

anterior soleus tendon fibers run posteromedial (Cummins et al. 1946, Stein et al.

2000). The AT is not simply straight in its micro architecture as the collagen

fibers and fibrils of the tendon assume a wavy configuration when the tendon is

unstretched. If the tendon is stretched by 2 %, this wavy configuration disappears;

more than 4 % stretching causes irreversible changes. Stretching to more than 8 %

causes macroscopic failure and tendon rupture (O`Brien 1992).

Fibroblasts are the dominant cells in the AT, but major part of the AT consists

of extracellular matrix. The dry weight of collagen content of the AT is about

70 % (Jozsa et al. 1989b), and most of the collagen is type I collagen. A small

amount of type II collagen is found in the osteotendinous junction and types III,

IV, and V are found in the endotenon (Jozsa & Kannus 1997). Collagen turnover

is relatively slow, ranging from 50–100 days (Curwin & Stanish 1984).

Metabolism can speed up after injury, but immobilization decreases collagen

synthesis and increases its degradation, thereby reducing tendon strength

(Karpakka et al. 1991).

Over the years, the tensile strength of the healthy AT decreases, reaching

about 40 % of its value by the age of 70 years when compared to 30 years

20

(Barfred 1973, Thermann et al. 1995). Repeated microtraumas that cause

histological changes in the AT and in type III collagen content are significantly

increased upon rupture (Kannus & Jozsa 1991, Pajala et al. 2002). Biomechanical

factors, like an underpronating foot and an ankle type linked with poor shock

absorption, will increase the strain on the AT and may result in AT overuse

injuries and ATR (Kvist 1991, Leppilahti et al. 1998). A study by Davis et al.

(1991) on military recruits reported that black people had an increased risk for

ATR when compared with caucasians and that this higher risk could not be

explained by differences in sports training alone.

Some drugs, especially fluoroquinolones, increase the risk for ATR (Sode

2007). Some investigations have suggested that statins, given to treat

hypercholesterolemia, might also have some effect on tendons (Beri et al. 2009,

Marie et al. 2008), and studies using animal models have reported decreases in

the biomechanical strength of the AT with statin use (de Oliveira 2015). The exact

mechanism underlying the effect of these drugs on the occurrence of ATR remains

to be established. Anabolic hormone abuse leads to dysplasia of collagen fibrils,

reducing the tensile strength of the AT and increasing the risk for ATR (Laseter &

Russel 1991). Oral and locally injected corticosteroids are generally considered as

a risk factor for ATRs (Claessen et al. 2014, Spoendlin et al. 2015, van

Sterkenburg & van Dijk. 2011), even if the corticosteroids are not injected just

next to the tendon (Turmo-Garuz et al. 2014). Pre-existing intratendinous diseases

(e.g., rheumatoid nodule, gout affection, xanthoma, and tumors) are uncommon

causes for ATR (Kannus & Jozsa 1991).

21

Fig. 1. Anatomy of Achilles tendon according to Jean-Baptiste Sarlandière.

2.2 Acute ATR

2.2.1 Diagnosis

ATR is an injury mostly associated with young and healthy active individuals. It

occurs during a sudden forced ankle dorsiflexion, mostly during sports exercises

or by stepping in a hole.

The majority of ATRs occur 2–6 cm above the heel bone (Fox et al. 1975),

possibly because the vascularity of the tendon is decreased in that area, as shown

in an angiographic study (Lagergren & Lindholm 1959). The typical patient

history and symptoms make clinical diagnosis of ATR usually easy. One quarter

of these patients typically has had previous AT problems, 56 % during the 3

months preceding the rupture. The patients with previous AT symptoms are

22

younger and more often competitive athletes and often have had a sports-related

injury mechanism (Leppilahti et al. 1996).

Typically, a patient undergoing an ATR will feel a sudden pain and a snap in

the lower calf – a feeling as if somebody has kicked the AT. A palpable gap in the

ruptured area can be found in about 70 % of patients, and in about 80 % if tested

under anesthesia (Maffulli 1998).

Some clinical tests can help improve the diagnostic accuracy. The Thompson

test is easy and accurate for diagnosing a complete ATR (Cuttica et al. 2015,

Maffulli 1998). This test is done by squeezing the calf of the affected leg, which

is placed at a 90-degree angle on a chair, while the opposite leg remains standing.

The absence of ankle plantar flexion is suggestive of a complete ATR and is

termed a "positive" Thompson test (Thompson & Doherty 1962).

The O’Brien test involves insertion of a 25-gauge needle 10 cm proximal to

the superior border of the calcaneus, such that it penetrates the AT. The ankle is

then alternated with passive dorsiflexion and plantar flexion movements. The

absence of needle movement means a positive test result and indicates an ATR

(O’Brien 1984). The Copeland test is done with the patient in a prone position

and the knee is flexed 90 degrees. A sphygmomanometer cuff is applied around

the calf muscle and inflated to approximately 100 mmHg, with the ankle plantar

flexed. Passive dorsiflexion of the ankle will cause no change in the pressure in

the case of a ruptured AT, but a healthy tendon will cause a rise of about

140 mmHg. The opposite leg may be used as a control, for comparison purposes

(Copeland 1990). However, the sensitivity of these two tests is only slightly better

than clinical evaluation (Maffulli 1998).

Even if ATR diagnosis is mostly based on clinical examination, technical

devices can be used to support the diagnosis. X-ray was used in ATR diagnosis

for several decades. Kager described the appearance of the “Kager triangle” – the

normal triangular pre-Achilles fat pad – on lateral x-rays, which has been

regarded as diagnostic for ATR (Kager 1939). Electromyography (EMG) has also

been used for diagnosis, especially for partial ruptures (Ljungqvist 1968). At

present, US is the gold standard for confirming rupture and for determining the

appropriate treatment option (Amlang et al. 2011, Thermann et al. 1989). In

conservative treatment, US can also be used to monitor the healing processes

(Walz et al. 1993). It is inexpensive and readily available, but its results are also

highly investigator dependent. AT injuries can also be diagnosed confidently by

magnetic resonance imaging (MRI) (Keene et al. 1989), but its availability is

23

limited compared to US. In differential diagnosis between partial and complete

tears, MRI is superior to US (Kayser et al. 2005).

2.2.2 Epidemiology

The incidence of ATRs has been studied quite appreciably in northern European

countries over the last 3 decades (Ganestam et al. 2015, Houshian et al. 1998,

Leppilahti et al. 1996, Levi 1997, Mattila et al. 2014, Möller et al. 1996, Nillius

et al. 1976, Nyyssönen et al. 2008, Rantanen et al. 1993, Wählby 1978). Studies

have also been conducted in Scotland (Clayton & Court-Brown 2008, Maffulli et

al. 1999) Canada (Scott et al. 2014, Suchak et al. 2005), Slovenia (Cretnik et al.

2010), New Zealand (Gwynne-Jones et al. 2011), and the United States (Raikin et

al. 2013, White et al. 2007). The study populations of these previous studies are

heterogenic, containing patients from very different backgrounds, and the studies

have included both acute and chronic ATRs from the year 1936 (Christensen

1954) to 2013 (Ganestam et al. 2015). This has resulted in wide variation in the

reports of the overall incidence per 100 000 person-years in these different

studies, from 2.1/100 000 (Leppilahti et al. 1996) to 37.3/100 000 (Houshian et

al. 1998).

Almost all the studies assessing changes in epidemiology have shown an

increasing incidence. This increasing incidence is also reflected in more recent

studies, which report a higher overall incidence than reported in the older studies.

A previous study from our Oulu University hospital showed an increasing

incidence over a 16 year period from 1979 to 1994. The incidence increased from

2/100 000 in 1979 to 18/100 000 person-years in 1994 (Leppilahti et al. 1996).

The total incidence in Finland between 1987 and 1999 has been reported as

11.2/100 000, but this study examined only operatively treated ruptures

(Nyyssönen et al. 2008). The longest time period and the largest study population

in these previous studies is that from the National Patient Registry of Denmark,

which ran from 1994 to 2013 and included 33 160 ATRs. It showed a clear

increase in the incidence from 27.0 in 1994 to 31.2/100 000/person-years in 2013

(Ganestam et al. 2015). The Finnish data show an increasing incidence during the

80s and 90s, but whether the incidence has continued to grow after the year 2000

remains unclear.

In all the epidemiological studies, the majority of ATRs are sports related.

The ATR typically occurs during sports that require sudden acceleration and

jumping, such as badminton, volleyball, soccer, and basketball, but considerable

24

national differences are evident (Houshian et al. 1998, Jozsa et al. 1989,

Leppilahti et al. 1996, Raikin et al. 2013, Suchak et al. 2005). Previous studies

have shown that about 25 % of ATRs are non-sports related (Jozsa et al. 1989,

Leitner et al. 1991), but the specific changes in the incidence of sports-related

ruptures are unclear. The median age at the time of the injury, reported in previous

studies, has been quite similar, from 42 to 47 years (Ganestam et al. 2015,

Houshian et al. 1998, Huttunen et al. 2014, Leppilahti et al. 1996, Nyyssönen et

al. 2008, Raikin et al. 2013). Another common factor in these previous studies is

that ATR is 2 to 6 times more common in men than in women; even greater

differences have been proposed by Maffulli et al. (1999).

The seasonal variation of ATRs is controversial. Two studies one in Finland

and another one in Canada found no statistically significant seasonal variation in

the incidence (Nyyssönen et al. 2008, Suchak et al. 2005), whereas Scott et al.

found an increase in the number of cases in spring in terms of sports-related

ruptures (Scott 2013). Contrary to these findings, Ganestam et al. (2015) found a

higher incidence during the fall, with a peak incidence in September.

2.3 Treatment of acute ATR

ATRs can be treated operatively (open or percutaneous) or nonoperatively.

Historically, ATR has been treated nonoperatively with different kinds of

bandages or braces for varying periods (Wills et al. 1986). As early as the 1920s,

surgery was proposed as the treatment of choice in the French literature (Quenu &

Stoianovitch 1929). Studies favoring surgery (Arner & Lindholm 1959,

Christenssen 1954) made operative treatment more popular, despite reports of

good results with conservative treatment (Gillies & Chalmers 1970, Lea & Smith

1968). An editorial appearing in the Lancet in 1973 raised doubts regarding the

superiority of operative treatment compared to conservative treatment.

Nevertheless, operative treatment became frequent, especially among active

young patients, and the conservatively treated patients were mostly elderly

patients or patients with high operation-related risks.

Different kinds of percutaneous techniques have been described since 1977,

when Ma & Griffth (1977) reported their results for 18 patients treated with

percutaneous sutures. However, percutaneous techniques have not challenged

open operative techniques as the most commonly used treatment. During the past

few years, several high quality studies have been published, including systematic

reviews and meta-analyses comparing operative and nonoperative treatments

25

(Bhandari et al. 2002, Holm et al. 2015, Jiang et al. 2012, Khan et al. 2005,

Soroceanu et al. 2012, Wilkins et al. 2012, Wong et al. 2002) and the trend has

been in a more conservative direction (Ganestam et al. 2015, Mattila et al. 2013).

2.3.1 Conservative treatment

The most common conservative treatment method has traditionally been a below-

the-knee cast for 6–10 weeks, starting with plantar flexion and changing the cast

to a normal position, usually with no or only partial weight bearing. The use of a

rigid cast in nonoperative treatment has decreased and functional treatment has

increased in the last decade. Experimental studies have shown that

immobilization of a muscle in a shortened position is deleterious and causes more

histological changes, whereas immobilization in a stretched position markedly

delays the development of atrophy (Hurme et al. 1990, Rantanen et al. 1999).

Functional treatment consists of braces and casts worn for varying times.

Patients are normally encouraged to weight bear, starting at weeks 0–3,

depending on the protocol. Usually, some range-of-motion (ROM) exercises are

also possible for the tibiotalar joint. McComis et al. (1997) reported good results

with a functional nonoperative treatment as early as 1997 with a limited (15

patients) sample size.

Wallace et al. (2011) had treated 946 patients with a functional conservative

protocol in a prospective study and observed a re-rupture rate (2.8 %) similar or

even smaller than that published for operative treatments. Functional bracing

showed a lower re-rupture rate than was observed with cast immobilization in a

meta-analysis (Khan et al. 2005). Möller et al. reported a high re-rupture rate

(11/53) following conservative treatment in their randomized trial in 2001, but

other subsequent randomized trials reported lower re-rupture rates following

nonoperative treatment (Keating et al. 2011, Nilsson-Helander et al. 2010, Olsson

et al. 2013, Schepull et al. 2012, Twaddle et al. 2007, Willits et al. 2010).

Concerns have been raised regarding the rare complication of significant

lengthening of the AT, especially during functional conservative treatment

(Schepull et al. 2012).Therefore Hufner et al. (2006) suggested repeated US

controls in the first week in their conservative treatment protocol.

On the other hand, Costa et al. (2006) found no evidence of tendon

lengthening or a higher re-rupture rate when early mobilization with weight

bearing was compared with traditional plaster cast immobilization.

26

2.3.2 Operative treatment

Numerous variations in surgical techniques are available for the treatment of

ATRs (Wong et al. 2002). Generally, these techniques can be divided into open or

percutaneous techniques. Techniques with external fixation and tendon suturation

with fibrin glue have also been described, with very good outcomes (Hohendorf

et al. 2008, Nada et al. 1985). In most cases, surgery means simple end-to-end

saturation, augmentation with one or two gastrocnemius-soleus fascia flaps, or

local tendon augmentation. Cadaver studies have shown that augmentation

increases the gap resistance by as much as 29 % when compared with simple

sutures in AT repair (Gerdes et al. 1992, Lee et al. 2008). Two randomized

clinical studies that compared augmentation and non-augmentation operative

techniques (Pajala et al. 2009, Tezeren et al. 2006) reported no differences

between augmentation and non-augmentation in terms of AT performance score

or isokinetic strengths after 12 to 24 months of follow-up. However, Pajala et al.

(2009) found a more marked tendon elongation in the non-augmented group, and

tendon elongation was significantly correlated with strength deficits at 12 months

postoperatively. By contrast, one prospective and two retrospective studies have

found no differences between augmentation and non-augmentation in short-term

follow-up (Aktas et al. 2007, Jessing & Hansen 1975, Nyyssönen et al. 2003,).

Marked variation is also evident in the percutaneous techniques. The most

frequently used techniques are variations of the protocol described by Ma &

Griffith in 1977 (Wong et al. 2002). Percutaneous techniques are often associated

with lower postoperative infection, but they have a greater occurrence of sural

nerve problems when compared to open techniques (Buchgraber et al. 1997,

Cretnik et al. 2005). Two randomized controlled studies that compared

percutaneous and open techniques in a total of 94 patients (Lim et al. 2001,

Schroeder et al. 1997) reported that the pooled data showed a tendency for a

lower overall rate of complications (especially infections) in the percutaneous

group. A meta-analysis of retrospectively and prospectively collected data also

showed similar results, but other complication rates were relatively high in the

percutaneous group, particularly when percutaneous operations were combined

with functional postoperative treatment (Wong et al. 2002).

27

Postoperative treatment

After surgery ATR is usually treated with cast immobilization or some kind of

functional brace allowing more or less ankle movement. Functional postoperative

treatment became common in the 1990s. Current evidence now indicates that

early functional treatment with early weight bearing after ATR repair does not

increase the re-rupture rate and results in better patient satisfaction in the short-

term follow up period (Cetti et al. 1994, Costa et al. 2006, Kangas et al. 2003,

Maffulli et al. 2003, Metz et al. 2011, Schepull et al. 2013). Early mobilization

with weight bearing may decrease the adverse effects related to cast

immobilization but does not affect the long-term clinical outcome or isokinetic

calf muscle strength (Barfod et al. 2014, Kangas et al. 2003, Young et al. 2014).

Several meta-analyses have shown that early functional treatment protocols, when

compared with postoperative immobilization, lead to a greater number of

excellent ratings in subjective responses and a faster return to prior employment

and sporting activities, but no difference in complication rates (Maffulli et al.

2003, McCormack & Bovard 2015, Suchak et al. 2006, van der Eng et al. 2013).

Variations in functional treatment protocols are large and the efficacies of

different rehabilitation protocols are unclear (Kearney et al. 2012). However,

postoperative early weight bearing, combined with early ankle motion exercises,

appears to lead to better results when compared with early ankle motion exercises

alone (Huang et al. 2015).

2.3.3 High-quality evidence of operative vs. conservative treatment

Outcome measures

Analysis of different treatment methods in surgery obviously requires a reliable

system for comparing results. Concerning ATR, no consensus has been reached

on any single measuring system. Scores can be divided into generic health

outcome measures, like the 36-item questionnaire (SF-36), or disease and region-

specific outcome measures, like the American Orthopedic Foot and Ankle Society

(AOFAS) ankle-hindfoot score. Several different scoring systems have been used

in meta-analysis in recent years, including the short musculoskeletal scoring

system (Keating et al. 2011), musculoskeletal functional assessment instrument

(Twaddle et al. 2007), the Achilles tendon total rupture score (ATRS) (Nilsson-

Helander et al. 2010, Olsson et al. 2010, Schepull et al. 2012), the Leppilahti

28

score (Metz et al. 2008, Willits et al. 2010), the Foot and Ankle outcome score,

and the EQ-5D (a standardized instrument for use as a measure of health

outcomes) (Olsson et al. 2013). Among these scores, the ATRS and Leppilahti

score are specific for ATR.

Our study group has been using the Leppilahti score since it was published

1998. This score consists of subjective factors (pain, stiffness, muscle weakness,

footwear restriction, and subjective outcome) and objective factors (active ROM

of the ankle and the isokinetic calf muscle strength score) (Appendix 1). The

meta-analysis conducted by Kearney et al. in 2012 reported 4 generic quality-of-

life outcome measures and 17 region-specific outcome measures being used to

assess ATR outcomes. The AOFAS ankle-hindfoot score was the most frequently

used. The ATRS is the only formally validated score for ATRs; however, its

ceiling effect remains unclear (Kearney et al. 2012).

Strength recovery after an ATR has been assessed by a simple heel raise test

or by isometric or isokinetic strength measurements. Isokinetic measurements are

considered more physiological than are isometric measurements, especially

relative to gait. A large variety of isokinetic tests is available, but the peak torque

(PT) is the most frequently reported value, and it is normally reported regardless

of the angle in the ROM at which it occurs (Mullaney et al. 2006). The PT shows

a good correlation with calf muscle volume (Rosso et al. 2015). Reporting the

differences between the affected and non-affected leg as percentage deficits is

advisable, especially in long-term studies, because the absolute values can also

decrease due to aging if the study period extends over several years.

The average torque and total work have also proven to be reliable methods

for measuring the torque of the plantar flexors and outcomes after an ATR

(Chester et al. 2003). The clinical importance of small strength deficits are

unclear, but one study reported persistent impairment and a 30 % strength deficit,

resulting in gait adaptations observed in a two-year follow-up (Don et al. 2007).

Work differences in plantar flexion also reflect the strength capabilities of the calf

and have been used to show the differences between the affected and non-affected

legs (Pajala et al. 2009). Our unpublished data showed good to excellent

interclass correlation values for work displacement (appendix 2).

29

Randomized controlled trials (RCTs) comparing surgery and conservative

treatment

Studies comparing open operative and nonoperative treatments have been

published since the 1970s (Gillies & Chalmers 1970, Inglis et al. 1976, Jacobs et

al. 1978). The first randomized controlled study was launched in 1973, when

Nistor started his study in Göteborg. That study, which included 105 patients, was

published in 1981. Like most subsequent studies on the same subject, it reported

more re-ruptures in the nonoperative group and more surgery-related

complications in the operative group. Nistor concluded that “non-surgical

treatment offers advantages over surgical treatment” (Nistor 1981).

After Nistor´s work, 11 high-level RCTs comparing operative treatment with

nonoperative treatment were published (Cetti et al. 1993, Keating et al. 2011,

Majewski et al. 2000, Möller et al. 2001, Nilsson-Helander et al. 2010, Olsson et

al. 2013, Schepull et al. 2012, Schroeder et al. 1997, Thermann et al. 1995,

Twaddle et al. 2007, Willits et al. 2010). The study by Möller (2001) was the last

trial included in the meta-analyses of Bhandari et al. (2002) and Khan et al.

(2005). These meta-analyses did not use precisely the same trials; however, both

concluded that operative treatment reduces the risk of re-rupture, but is associated

with a significantly higher risk of infection. Khan et al. (2005) also found that

functional postoperative treatment reduces the overall complication rate;

however, this result was based on two studies (Petersen et al. 1992, Saleh et al.

2002) with a total combined number of only 90 patients. In the same year, Wong

et al. (2002) published a quantitative review of retrospective and prospective

studies and recommended open repair and early mobilization, with a general

complication rate of 6.7 %.

After these meta-analyses, three high-quality RCTs were published, which

were included in the meta-analyses of Jiang et al. (2012), Soroceanu et al. (2012),

and Wilkins et al. (2012). Although 291 new patients were included, the

conclusions remained practically unchanged. The functional outcomes or

returning of strength showed no significant differences, but the return to work

was slightly quicker in the operatively treated patients. Soroceanu et al. (2012)

found that nonoperative treatment, including early ROM, led to equivalent results

when compared with open operative treatment in terms of re-rupture rate, and

concluded that “conservative treatment should be considered at centers using

functional rehabilitation.”

30

In their quantitative review, Wong et al. (2002) found that the quality of

articles has improved and the rate of complications has decreased over time. A

recent systematic review by Holm et al. (2015) included only studies published in

last ten years (Keating et al. 2011, Metz et al. 2008, Nilsson-Helander et al. 2010,

Olsson et al. 2013, Schepull et al. 2012, Twaddle et al. 2007, Willits et al. 2010)

and summarized data from 584 patients. The majority of these patients had been

treated using functional protocols. One study (Metz et al. 2008) compared

nonoperative treatment to minimally invasive surgery, whereas the other studies

used open end-to-end sutures. No statistical significant differences were found for

patient satisfaction, pain, or re-ruptures, although two studies (Nilsson-Helander

et al. 2012, Olsson et al. 2013) found a difference of 2–4 % vs. 10–12 % favoring

operative treatment. Studies measuring different functional tests found some

slight differences favoring surgery, but the clinical importance of these findings is

unclear. The authors suggested that subtle differences between groups could mean

that rehabilitation is more important than the actual initial treatment.

In 2009, when we started to collect patients for our prospective randomized

study comparing operative vs. nonoperative treatments, studies with good

strength measurements were lacking. Since then, four randomized studies that

include strength measurements have been published. All reported results favored

surgery at least in the short term (Keating et al. 2011, Nilsson-Helander et al.

2010, Olsson et al. 2013, Willits et al. 2010). The effects of accelerated

postoperative rehabilitation on calf muscle strength are unclear, and only one

study has been published so far (Willits et al. 2010).

31

Table 1. Meta-analyses of randomized studies.

Study Year Bhandari Khan Jiang Soroceanu Wilkins Holm

Coombs 1981 x

Nistor 1981 x x x x x

Cetti 1993 x x x x x

Thermann 1995 x

Schroeder 1997 x x x

Majewski 2000 x

Möller 2001 x x x x x

Twaddle 2007 x x x x

Metz 2008 x x x x

Willits 2010 x x x x

Nilsson-

Helander

2010 x x x x

Keating 2011 x x

Schepull 2012 x

Olsson 2013 x

Table 2. Randomized controlled studies, operative vs. nonoperative treatment.

Study Year Oper/cons Re-rup. Re-rup. % Comp. Comp. % Strenght favor Recom

Nistor 1981 45/60 2/5 4.4/8.3 29/2 64/3 cons cons

Cetti 1993 56/55 3/7 5.3/12.7 17/5 30/9 0 oper

Schroeder 1997 13/15 0/0 0.0/0.0 2/0 15/0 0 ?

Möller 2001 59/53 1/11 1.7/20.8 10/2 17/4 0 oper

Twaddle 2007 25/25 2/1 10/4.5 0/0 0/0 0 0

Willits 2010 72/72 2/3 2.8/4.2 11/3 15/4 oper 24 m cons

Nilsson-

Helander

2010 49/48 2/6 4.4/12 18/0 36/0 oper 6 m, 12 m 0

Keating 2011 39/41 2/4 5.4/10 3/2 8/5 oper 3 m cons

Schepull 2012 15/15 0/1 0.0/6.7 0/4 0/26 0 0

Olsson 2013 49/51 1/5 2.0/10 21/4 42/8 oper 12 m 0

Total 422/435 15/43 3.6/10 111/20 26/4.6

Coombs 1981 was excluded because of inadequate reporting of results

Thermann 1995 because of inadequate randomization

Majewski 2000 because of discontinuation of treatment group

2.4 Long-term results of acute Achilles tendon ruptures

Only a few long-term follow-up studies after ATR have been conducted (Bevoni

et al. 2014, Hohendorff et al. 2008, Horstmann et al. 2012, Rosso et al. 2013,

32

Rosso et al. 2015, Zwipp et al. 1989). These studies have included patients

treated operatively, nonoperatively, minimally invasively, and with fibrin glue.

Only Bevoni et al. (2014) had a prospectively-designed study but no control

group. 66 patients included in the trial underwent identical surgical technique

with functional postoperative treatment and the length of follow-up was 3 years.

They found good results in terms of AOFAS and Leppilahti scores and no

significant difference with respect to isokinetic strength when compared to the

uninjured side. However, the study by Porter et al. (2014), operatively treated

patients with almost 3 years of follow-up time, demonstrated plantar flexion

deficits of the involved ankle ranging from 12–18 % for PT.

With a significantly longer follow-up, Horstman et al. (2012) found smaller

ankle ROM, heel height during heel-raise tests, and calf circumference on the

injured than on the contralateral side. Additionally, the total work in isokinetic

testing during a plantar flexion exercise at 180°/sec was 14.9 % lower in the

injured compared to the contralateral leg after 10 years. Rosso et al. (2015)

compared operative and conservative treatment in their retrospective study with 7

years of follow-up and found no difference in ATRS score, muscle volume, or AT

length between operatively and conservatively treated patients. The AT was

18 mm longer in the affected leg, while the PT was 13 % higher in the untreated

leg (Rosso et al. 2013 and 2015). Zwipp et al. (1989) reported no strength

parameters, but 90 % of the patients had excellent or good functional scores after

simple end-to-end suture in 10 years of follow-up.

In conclusion, the previous studies reported in the literature have shown that

ATR results in significant impairment of the leg for several years after treatment.

The weakness of these previous studies is that they have very heterogenic patient

populations, no randomization, and the results related to strength are conflicting.

33

3 Aims of the present study

The specific aims of this thesis were:

1. To assess changes in the epidemiology and injury mechanisms of acute ATR

in the city of Oulu. The main goal was to determine whether the incidence of

ATR has continued to increase since the year 2000, and to investigate

changes in epidemiology of sports and non-sports related injuries over the

past three decades.

2. To assess long-term functional results and calf muscle recovery in RCT,

comparing early functional treatment versus cast immobilization in tension

after ATR repair.

3. To compare nonoperative and operative treatment of acute ATR with similar

functional postoperative rehabilitation protocols in RCT. The main points of

interest were the functional result, detailed assessment of calf muscle

recovery, RAND 36-item health survey scores, and the effect of patient age

on the results.

35

4 Materials and methods

4.1 Epidemiology (I)

All closed ATRs in adult patients in the city of Oulu (Oulu University Hospital,

Oulu Deaconess Institute, Terveystalo Oulu, Mehiläinen Oulu, Oulu Military

Hospital) between 1.1.1979 and 31.12.2011 were included in the study. Data were

collected retrospectively from patient records until 1995, and since 1996 from

electronic medical records.

Demographic data, mechanism of injury, treatment method, and

complications were obtained from the medical records of each patient. The data

collected from years 1979–1994 and published previously (Leppilahti et al. 1996)

were re-assessed. 81 % of patients received operative treatments (429 cases),

including suturing with augmentation (n = 214), suturing without augmentation

(n = 203), and percutaneous suture techniques (n = 12). Non-operative treatments

(99 cases) included a cast (n = 53) and functional bracing (n = 46).

The total number of inhabitants and the age and sex distribution in the

population of Oulu over the study period was obtained from the Statistics Finland

website (Statistics Finland website, 2013).

The crude and gender specific incidences of ATRs were calculated per

100 000 person-years in Oulu inhabitants from 1979–2011. Age specific

incidences were calculated using 10-year intervals. The changes in incidence were

assessed in 10-year periods in each age group. Patients were also divided into two

age groups, under and over 40 years, because previous data suggested that

degenerative changes in the AT are more common on people older than 35 years.

Additionally, incidences in non-sports and sports-related injuries were calculated.

4.2 Long-term results of early functional treatment versus cast

immobilization in tension after ATR repair (II)

Study II was a long-term follow-up of a previously published RCT comparing

early postoperative mobilization (group 1) with early immobilization with cast

(group 2) in tension after surgical treatment of ATR (Kangas et al. 2003, 2007).

The inclusion criteria were complete acute ATR and age between 18 and 60 years.

The exclusion criteria were a delay of 1 week or more in treatment after the

rupture, systemic corticosteroid treatment and local corticosteroid injection(s)

36

around the AT for 6 months before the rupture, previous ATR on the opposite

side, living outside the country, and diabetes mellitus.

In total, 107 patients were screened for eligibility for the trial at Oulu

University Hospital between July 1995 and July 1998. Of these, 57 patients met

one or more exclusion criteria and 23 eligible patients refused to participate. The

primary study group consisted of 50 patients (47 men and 3 women, mean age 36

years, range 21–55 years). The mean age at the time of injury, body mass index

(BMI), and activity level (competitive athlete, recreational athlete, or nonathletic)

was recorded (Table 3). All patients were treated operatively using an identical

surgical technique proposed by Silfverskiöld (1941). Postoperative treatment was

randomized either to early mobilization or immobilization with cast.

Table 3. Demographic data on the Achilles Tendon Rupture patients in study II.

Property Group 1

(Early mobilization)

(n = 19)

Group 2

(Cast immobilization)

(n = 18)

p-value

Men/women 17/2 17/1 0.59

Mean age (SD) 36 (9) 34 (7) 0.61

Activity level

Competitive athlete 4 1 0.86

Recreational athlete 11 16

Nonathlete 4 1

BMI (SD) 26 (2.8) 26 (4.2) 0.8

4.2.1 Postoperative management

The postoperative treatment was not known at the time of the operation. The

patients were randomized on the first postoperative day to either early

mobilization or immobilization in tension, using 25/25 randomly mixed sealed

envelopes. The patients in the early motion group (group 1) received a below-

knee dorsal brace (3M Soft cast®) for 6 weeks. The brace allowed active free

plantar flexion of the ankle, but dorsiflexion was restricted to neutral. The patients

in the immobilization group (group 2) received a below-knee plaster cast (3M

Scotchcast®) with the ankle at a 90 degree angle for 6 weeks. Full weight bearing

was allowed after 3 weeks in both groups. Patients in both groups were instructed

to perform postoperative exercises according to a standard rehabilitation regimen

(Kangas et al. 2003).

37

4.2.2 Outcome Measures

Forty-eight patients (96 %) from the original study were contacted after minimum

of 10 years of follow-up. Thirty-seven patients (19 in group 1 and 18 in group 2)

were re-examined in 2008, after an average of 11 (SD 0.9) years of follow-up

(Fig. 2). The primary outcome measure was the Leppilahti score (Appendix 1) at

the 11-year follow-up. Secondary outcomes included the isokinetic and isometric

strengths of the calf muscles. Complications and potential reoperations were also

recorded. Patients visited the outpatient clinic 3, 6, and 14 months and 11 years

after surgery. The clinical observers were not blinded to the postoperative

treatment group.

Fig. 2. Flow chart of Early Functional Treatment versus Cast Immobilization in tension.

Assessed for eligibility (n = 107)

Excluded (n = 57)• Not meeting inclusion criteria (n = 22)• Declined to participate (n = 23)• Living outside the country (n = 12)

Randomized after operation (n = 50)

Immobilization in tension (n = 25)

3‐month follow‐up• Leppilahti score and strength tests6‐month follow‐up• Strength tests14‐month follow‐up• Leppilahti score and strength tests

Lost to follow‐up/excluded (n = 7)• Living abroad (n = 3)• Declined to participate (n = 2)• Paralyzed (n = 1)• Excluded from analysis (n = 1)(ankle arthrodesis innonaffected leg

Analyzed (n = 18)• Leppilahti score and strength tests

Early mobilization (n = 25)

3‐moth follow‐up• Leppilahti score and strength tests6‐month follow‐up• Strength tests14‐month follow‐up• Leppilahti score and strength tests

Lost to follow‐up/excluded (n = 6)• Living abroad (n = 2)• Declined to participate (n = 1)• No contact (n = 1)• Deceased (n = 1)• Excluded from analysis (n = 1)(knee operation to nonaffected leg)

Analyzed (n = 19)• Leppilahti score and strength tests

Enrollment

Allocation

3‐ to 14‐mofollow‐up

11‐yearfollow‐up

Immobilization in tension (n = 25)• Received allocated intervention (n = 25)

Early mobilization (n = 25)• Received allocated intervention (n = 25)

38

A physiotherapist performed all strength measurements using a computer-based

isokinetic dynamometer (appendix 2). After the isokinetic tests, the maximal

isometric plantar flexion strength was measured with the ankle in the neutral

position. The PT, average work, and isometric strength results were measured for

both legs.

The groups were compared using the unaffected ankle as a reference. The

relative deficit ([unaffected − affected side]/ unaffected side x 100 %) in PT,

average work, and isometric strength were calculated. The injured and non-

injured sides were compared using absolute values of PT and average work. The

average work (measured in joules) was defined as the sum of the total area under

all the torque-angular displacement (time) plots and was measured as the mean of

the five best repetitions of the test. Additionally, for the 11-year control, the

repetition with the highest plantar flexion PT value was selected, and work-

displacement curves (−15 degrees to 35 degrees) for both calves were calculated

to assess the work deficits for each 10-degree interval over the ROM of the ankle

joint.

4.3 RCT comparing surgery with conservative treatment (III)

All patients with acute ATR treated at Oulu University Hospital between April

2009 and November 2013 were screened for trial eligibility. The inclusion criteria

were complete acute ATR and age between 18 and 65 years. The exclusion

criteria were a delay of ≥ 1 week between the rupture and treatment, local

corticosteroid injection(s) around the AT within 6 months before the rupture,

previous surgery on the lower leg, previous ATR on the opposite side, open ATR,

pregnancy, skin problems over the area of the AT, living outside the area, diabetes

mellitus, or a persistent gap between the ruptured tendon ends in passive plantar

flexion as assessed by US.

Two investigators examined all eligible patients and assigned them to

interventions. Total ATR was diagnosed if a clear gap was palpable in the AT and

the Thompson’s test was positive. A radiologist confirmed the diagnosis by US

examination of the AT within 2 days after the injury. The radiologist also assessed

whether the tendon ends could be reduced in passive plantar flexion of the ankle

joint with the knee extended. A total of 258 patients were screened for trial

eligibility; 124 patients were excluded and 74 eligible patients refused to

participate. Thus, the study group comprised 60 patients, including 53 men and 7

women, with a mean age of 39.3 years (range 27–60 years) (Fig. 3).

39

Fig. 3. Flow chart of the prospective randomized trial comparing surgery and

conservative treatment.

4.3.1 Conservative Treatment

Non-surgical treatment started with a non-weight bearing full equinus cast for the

first week. After 1 week, the cast was changed to an orthosis (Vacoped®). The

ankle was positioned at 30° plantar flexion for weeks 2 to 3, 15° plantar flexion

for weeks 4 to 5, and free movement from 0° to 30° plantar flexion for weeks 6 to

7. Full weight bearing was directed and encouraged during the orthosis

immobilization. After week 7, a 1-cm heel raise was used for 1 month. Cycling

Assessed for eligibility (n = 258)

Randomized for treatment (n = 60)

Excluded (n = 198)• Not meeting inclusion criteria(n = 124)

• Declined to participate (n = 74)

Surgery (n = 32) Conservative treatment (n = 28)

Isokinetic strength tests• n = 25• 3 missing; unsuitable follow‐up time


Leppilahti score• n = 28Isokinetic strength tests and Rand‐36• n = 28

Leppilahti score• n = 29• Missing 3; one or more required angular velocity for score was missed

Isokinetic strength tests and Rand‐36• n = 32



Enrollment

Allocation

3 months

6 months

18 months

40

and swimming exercises were recommended at 2 months; jogging began at 3

months. Sports involving sudden acceleration and jumping were allowed after 6

months.

4.3.2 Surgical Treatment

Surgery was performed within 7 days of the injury. Four surgeons were involved

in the operations. One surgeon operated on 29 patients and three surgeons each

operated on one patient. The Krackow locking loop technique (two non-

absorbable sutures and smaller apposition sutures) was used in all patients

(Krackow 1986). After surgery, the patients received a full equinus cast for 1

week, without weight bearing. The postoperative treatment was identical to the

conservative treatment protocol.

4.3.3 Outcome Measures

The primary outcome measure was the Leppilahti score at the 18-month follow-

up. Secondary outcomes included calf muscle isokinetic strengths measured at 3,

6, and 18 months after the injury and the health-related quality of life (HRQoL)

measured by the RAND 36-item health survey at 18 months (Aalto et al. 1999).

Complications and potential re-operations were also recorded. The assessors of

the outcomes were not systematically blinded to the treatment method.

Strength measurements were performed by an experienced physiotherapist

and an exercise physiologist (appendix 2). Peak plantar flexion torque at an

angular velocity of 60 degrees/s was recorded for each leg, based on the best

repetition. Torque deficits over the ankle joint’s ROM were assessed by recording

PT values at specific angles (0°, 10°, and 20°), based on five repetitions for both

calves.

The effect of age on the Leppilahti score, PT, and re-rupture rate was the only

pre-planned subgroup analysis.

4.4 Ethics (I, II, III)

The ethical committee of Oulu University Hospital approved all study protocols

(I–III) and re-examination of the patients (II). All patients in study II and III

received oral and written information about the trial and provided informed

consent to participate.

41

4.5 Statistical methods (I, II, III)

Summary measurements are presented as means ± SDs or medians with

interquartile range, unless otherwise stated. Simple between-group comparisons

were analyzed by the Student t-test (continuous variables) and the chi-squared or

Fisher exact test (categorical variables).

Repeated-measures data were analyzed using a linear mixed model (LMM) in

which patients were set as random effects and the correlation between

measurements was taken into account by testing different covariance patterns.

The best pattern was chosen according to the Akaike information criteria.

P-values reported as the result of LMM analyses were as follows: Ptime, overall

change over time; Pgroup, average difference between groups; and Ptime 3 group.

Two-tailed p-values and 95 % confidence intervals (CIs) are presented. A p-value

< 0.05 was considered significant.

In study II, mixed sealed envelopes were used for randomization. In study III,

a biostatistician generated a random allocation sequence using computer software.

A randomly varying block size (4, 6, or 8) was used, each block having an equal

number of surgically and conservatively treated patients. To control the possible

confounding effect of age, the randomization was performed separately in two

age groups (≤ 35 and > 35 years) with the ratio of 1/3 (n = 20) and 2/3 (n = 40),

respectively.

The sample size (study III) was calculated using the Leppilahti score. The

clinically significant difference was set at 10 points, standard deviation 10, alpha

0.05, and beta 0.10, resulting in 17 patients in each group. To compensate for an

estimated dropout rate of 30 %, a total of 60 patients were to be enrolled in the

study.

43

5 Results


Between 1979 and 2011, 515 patients (456 male, 59 female) experienced 528

ATRs in Oulu. The mean age at the time of rupture was 43 years (SD 13, range

19–90) for all patients; 42 years (SD 13, range 19–79) for men and 46 years

(SD 15, range 23–90) for women. The ruptures were sports-related in 371 (70 %)

cases and non-sports-related in 157 (30 %) cases. The sports that were most

frequently associated with ruptures were badminton (113 ruptures), volleyball (70

ruptures), and football (59 ruptures), comprising 65 % of all sports-related

ruptures.

The overall incidence per 100 000 person-years increased from 2.1 (95 % CI

0.3 to 7.7) in 1979 to 21.5 (95 % CI 14.6 to 30.6) in 2011. The peak annual

overall incidence was 26.6/100 000 person-years in 2007 (Fig. 4). Among men,

the incidence increased from 4.5 to 39.5/100 000 person-years from 1979 to 2011.

Among women, the incidence rose from 0 to 4.1 from 1979 to 2011 (Fig. 4). The

incidence increased in all age groups (Fig. 5). A biphasic pattern became obvious

in males when the age-specific incidences were divided into sex-specific

incidences (Fig. 6).

44

Fig. 4. The incidence of Achilles tendon ruptures from 1979 to 2011 (The time series

was smoothed by calculating a 3-year moving average for each year).

Fig. 5. The age-specific incidence of Achilles tendon ruptures.

45

Fig. 6. Age- and sex-specific incidence of Achilles tendon ruptures.

The incidences of sport- and non-sport-related ATRs are shown in figure 7. The

patients with non-sports-related ruptures were significantly older (mean age, 53.4

years) and more frequently women (50 %) compared to those with sports-related

ruptures (mean age, 38.3 years, 26.9 % women; p < 0.001 for both; Fig. 8 and

Fig. 9). The incidence of ATRs increased over time in all age groups, for both

sports-related and non-sports-related groups (Fig. 8 and Fig. 9). In non-sports

related injuries (Fig. 8), the age-specific incidence increased during both the

second and third 11-year periods, particularly among individuals aged 60–69

years. In sports-related ruptures (Fig. 9), the age-specific incidence increased

sharply during the second 11-year period, but it only increased slightly during the

third 11-year period. The peak incidence also shifted towards a younger age group

during the second 11-year period.

46

Fig. 7. The incidence of sport- and non-sport-related Achilles tendon ruptures.

Fig. 8. The age-specific incidence of non-sport-related Achilles tendon ruptures for

each 11-year period.

47

Fig. 9. The age-specific incidence of sport-related Achilles tendon ruptures for each

11-year period.

5.2 Early functional treatment (group 1) versus cast immobilization

(group 2) after ATR repair (II)

5.2.1 Leppilahti Score

The mean Leppilahti score was 92.9 (SD 5.6) in group 1 vs. 93.6 (SD 7.2) in

group 2 (p = 0.68). The result in group 1 was classified as excellent for 16 (84 %)

and good for 3 (16 %) patients, whereas it was excellent in 14 (78 %) and good in

4 (22 %) patients in group 2 (Fig. 10). No statistically significant difference was

found between the groups in terms of pain, stiffness, subjective calf muscle

weakness, footwear restrictions, ROM of the ankle joint, and subjective results.

The subjective results at 11 years of follow-up were identical in both groups;

90 % were very satisfied and 10 % satisfied.

20 ‐ 29 30 ‐ 39 40 ‐ 49 50 ‐ 59 60 ‐ 69 70 ‐ 79 80 ‐

Age group

Incidence / 100 000 person‐years

40

35

30

25

20

15

10

5

0

1979 ‐ 19891990 ‐ 20002001 ‐ 2011

48

Fig. 10. Leppilahti score at follow-up: early motion versus cast immobilization in

tension.

5.2.2 Isokinetic and isometric calf muscle strength

The mean isokinetic plantar flexion PT deficits or average work deficits in plantar

flexion showed no differences between the groups with any angular velocity at

any time point. The mean work upon plantar flexion did not differ at any of 5

angular displacements (−15 to 35 degrees) between the groups (Fig. 11).

The isokinetic muscle strength of either ankle did not change substantially

between 14 months and 11 years. The mean isokinetic plantar flexion strengths

showed differences of up to 5.9 % in PT and differences of 8.9 % in average work

between the injured and non-injured side at the 11-year follow-up

(p < 0.001group, Fig. 12).

The mean isometric plantar flexion strength deficit between the injured and

non-injured sides in the early motion group diminished from 15.9 % to 1.7 %

between 14 months and 11 years, whereas this deficit in the cast group diminished

from 8.5 % to 3.1 % in the same time interval (ptime = 0.001). The mean relative

isometric plantar flexion deficit was 2.4 % when comparing the injured vs. non-

injured sides at the 11-year follow-up.

49

The work deficit for 10-degree intervals ranged from 4.6 % at (−15 degree to

−5 degree) dorsiflexion to 14.9 % (25 degree to 35 degree) plantar flexion for the

injured side at the 11-year follow-up, but the interaction between angular

displacement and ankles was not statistically significant (p = 0.098, Fig. 12).

Fig. 11. The median (error bars represent the 25th and 75th percentiles) peak work in

plantar flexion measured in 10 intervals at the 11-year follow-up between groups.

50

Fig. 12. The median (error bars represent the 25th and 75th percentiles) peak work in

plantar flexion measured in 10 intervals at 11.1-year follow-up. Whole study

population: operated versus healthy leg.

5.2.3 Complications / Re-operations

One deep infection and three re-ruptures occurred at a mean of 5 months (range,

3–7 months) after the primary operation. In group 1, one patient had a re-rupture

and one patient had bi-lateral ATRs at 1.5 years after the primary ATR. In group 2,

one patient had a re-rupture and the same patient had bi-lateral ATRs at 2 years

after the primary ATR. In addition, one patient had a re-rupture plus a deep

infection, required two microvascular reconstructions, and the AT was lost.

5.3 A prospective randomized trial comparing surgery and

conservative treatment (III)

5.3.1 Leppilahti score

At the 18-month follow-up, the mean Leppilahti scores were 79.5 (SD 10.3) and

75.7 (SD 11.2) for surgically and conservatively treated patients, respectively

51

(mean difference 3.8 points, 95 % CI -1.9 to 9.5, p = 0.19). The results were

excellent for 8 surgical patients (28 %), good for 11 surgical patients (38 %), and

fair for 10 surgical patients (34 %). For conservatively treated patients, scores

were excellent for 4 (14 %), good for 15 (55 %), fair for 6 (21 %), and poor for 3

(11 %). The groups did not differ in terms of pain, stiffness, subjective calf

muscle weakness, footwear restrictions, ankle joint ROM, or subjective results.

5.3.2 Isokinetic calf muscle strength

At the 3-month follow-up, both groups achieved similar mean PT results, but at 6

months, the advantage for surgically treated patients was 24 % (mean difference

14.8 Nm, 95 % CI 2.7 to 29.9, p = 0.017). The difference between the study

groups decreased to 14 % at 18 months follow-up; the average PT for the surgical

group was 110.3 Nm vs. 96.5 Nm in the conservatively treated group (mean

difference 13.6 Nm, 95 % CI 2.0 to 25.1, p = 0.022) (Fig. 13).

Angle-specific PT curves at the 18–month follow-up had an almost similar

shape, but surgically treated patients achieved 9.8 % to 17.9 % higher values

throughout the ankle ROM (Fig. 14).

Fig. 13. Median peak torque values (error bars represent the 25th and 75th percentiles)

for plantar flexion of the affected and healthy legs measured at 3, 6, and 18 months.

52

Fig. 14. Median angle-specific peak torque values (error bars represent the 25th and

75th percentiles) over the whole end ROM of the ankle joint in plantar flexion at the 18-

month follow-up.

5.3.3 RAND 36-Item health survey

The RAND 36-item health survey indicated better results for surgically treated

patients in the domains of physical functioning and bodily pain (Table 5).

Table 4. RAND 36-item health survey scores at the 18-month follow-up.

Domain Surgery1

n = 32

Conservative1

n = 28

p-value2

Physical functioning 97 (5) 88 (16) 0.006

General health 83 (12) 76 (21) 0.12

Mental health 85 (13) 85 (15) > 0.9

Social functioning 95 (11) 94 (13) > 0.9

Vitality 78 (14) 78 (18) > 0.9

Bodily pain 87 (15) 74 (27) 0.037

Role functioning/physical 97 (11) 89 (26) 0.16

Role functioning/emotional 95 (17) 91 (23) 0.56

1 Values are presented as mean (standard deviation), 2 Student’s t-test comparing the two groups.

53

5.3.4 Age

In patients ≤ 35 years of age, the Leppilahti scores in surgically and

conservatively treated patients were 81.3 (SD 11.7) and 76.0 (SD 9.9) (mean

difference 5.3 points, 95 % CI -4.4 to 14.9, p = 0.27) and the average PTs were

108.0 (SD 21.9) Nm vs. 99.2 (SD 19.0) Nm (mean difference 9.7 Nm, 95 % CI

-8.7 to 27.9, p = 0.29), respectively. In patients > 35 years of age, the Leppilahti

scores were 78.2 (SD 9.3) and 75.6 (SD 12.1) (mean difference 2.7 points,

95 % CI -4.7 to 10.1, p = 0.47) and the average PTs were 111.1 (SD 23.0) vs. 94.9

(SD 26.7) (mean difference 16.2 Nm, 95 % CI -0.46 to 32.9, p = 0.056),

respectively, in surgically and conservatively treated patients.

5.3.5 Complications

Four (14 %) re-ruptures occurred in the conservatively treated group and one

(3 %) re-rupture occurred in the surgical group. In the conservatively treated

group, three re-ruptures occurred during immobilization and one partial re-rupture

occurred 4 months after the primary injury. One patient in the surgery group had a

deep wound infection, which was treated by debridement and antibiotics. Patient

age had no effect on the rate of re-rupture.

55

6 Discussion

6.1 General considerations

Our studies have several strengths. In the epidemiological study, we had available

the comprehensive patient data from all hospitals in the Oulu area. All hospitals

provided reliable patient data, and electronic patient records were available after

1996. In addition, we included the tendon ruptures with delayed diagnoses –

which are rare – that were treated in our hospital. To our knowledge, this is the

first study to report an increasing incidence of ATRs due to non-sports-related

injuries. Studies II and III included a prospective, randomized design and

homogenous groups of patients. The number of patients lost to follow-up was

low. One surgeon treated almost all the patients in both studies, the same

physiotherapist performed all the muscle strength measurements, and the same

isokinetic dynamometer was used throughout the whole follow-up.

Our study also had some limitations. Study I was retrospective, and its

demographic data were collected from routine medical records. It is possible that,

during the 1970s and 1980s, patient records may not have been as comprehensive,

and the operation statistics and outpatient visits may have not been as accurate, as

those currently available. On the other hand, during the early years of the study,

treatment was mostly operative and data about operations were comprehensively

recorded.

Because of our free communal healthcare system, it is unlikely that patients

with acute ATR did not seek treatment from local hospitals. Since the 1980s, the

introduction of ultrasound and MRI may have improved diagnostics; however,

equivalent reports of this dramatic increases in the incidence of ATR have not

been published in the last decades. The diagnosis of ATR has always relied on

clinical examination; better imaging techniques are unlikely to explain the rise in

incidence. In addition, recent studies have shown no difference in diagnostic

accuracy between clinical examination and MRI (Garras et al. 2012).

Furthermore, our series may have missed some patients with ATR that

temporarily lived outside our Hospital’s catchment area; however, we assumed

that this would be a very small number of patients and that this omission would

not significantly affect our results.

56

A limitation of study II and III is that the clinical observers who performed

the isokinetic strength tests were not systematically blinded to the treatment

modality. Many eligible patients also refused to participate in the studies.

In study II, the period between the follow-up visits was long. Therefore, we

could not determine the exact time frame of isometric strength recovery. In study

III, the subgroup analysis assessing the effect of age on calf muscle strength may

be underpowered, so a larger number of patients is needed to confirm these

results. All patients received identical rehabilitation instructions after

immobilization, but we could not monitor the compliance of the patients with

their exercise program.


This study showed that the incidence of ATR has increased in all age groups over

the 33-year study period. We observed that the peak incidence occurred in the 30–

39 year age group; in a previous study from Oulu, the peak occurred in the 40–49

year age group, which suggested that current ruptures tend to occur at a younger

age. The age- and sex-specific incidences also increased, indicating a change in

the epidemiology of ATRs. Sports-related injuries remained the most common

etiology, but the incidence of non-sports-related ruptures has increased more

rapidly than that of sports-related ruptures.

The results of this study supported results from earlier investigations, which

reported increases in the incidence of ATRs in western countries. The main reason

for the tremendous increase in ATRs in the late 1980s was probably the increase

in the popularity of ball games in Oulu. The building of three sports halls in the

city of Oulu in the late 1980s allowed middle-aged residents to take part in

recreational ball games to an increased extent. The incidence of sports-related

ruptures increased sharply from 1979 to 1999, but it remained nearly constant

over the last 11-year period of this study. On average, 73–83 % of ATRs occur

during sports that require sudden acceleration and jumping (Gwynne-Jones et al.

2011, Levi 1997, Suchak et al. 2005). About 75 % of the ATRs occur during

recreational sports; 8–20 % occurred during professional sports; and about 10–

12 % were non-sports-related ruptures (Leppilahti et al. 1996).

We found that the incidence of non-sports-related ruptures has particularly

increased since the 1990s. In our series, non-sports-related ruptures occurred three

times more frequently than previously reported (Leppilahti et al. 1996). In

contrast to sports-related ruptures, the incidence of non-sports-related ruptures has

57

increased steadily, even during last 11-year period of our study. Previous studies

have reported that most patients with low energy ruptures exhibited degenerative

changes in the AT (Kannus & Jozsa, 1991). The basic etiology of these changes is

known to be multi-factorial (Järvinen et al. 2005), but aging is considered a

strong factor. Therefore, the reason for the increase in the age-specific incidence

of non-sports-related ruptures over time is unclear. Non-traumatic ATRs,

sometimes bilateral, can be caused by some medications, including

fluoroquinolone and systemic steroids. However, the use of these medications is

unlikely to have increased in our population over the studied time period. Some

investigations have suggested that statins, given to treat hypercholesterolemia,

might have some effect on tendons. (Beri et al. 2009, Marie et al. 2008) In animal

models, a decreased biomechanical strength of the AT has been reported with

statin use (de Oliveira 2015), but this association is controversial, and a potential

biological mechanism is unclear. Nevertheless, the use of statins has grown

rapidly over the last 15 years: about 15 % of the Finland’s population now uses

statins. The use of pronation-support shoes and insoles has also increased

significantly over the last two decades. These could have an effect on hindfoot

alignment, which is reported to be a factor in developing AT disorders (Waldecker

et al. 2012).

6.3 Early functional treatment versus cast immobilization in

tension after ATR repair (II)

Our results show that early mobilization and immobilization after surgical

treatment of ATR results in similar clinical outcomes and isokinetic strengths after

11 years of follow-up. We also found that isokinetic strength changed minimally

between 1 and 11 years, compared to the unaffected ankle, with a mean deficit of

5 % in PT and a mean deficit of 8 % in average work still present after 11 years.

On the contrary, isometric plantar flexion strength recovered significantly and

only a 2 % difference was noted after 11 years of follow-up. The shape of the

work-displacement curves in the affected and unaffected ankle was almost

identical, but a deficit of about 10 % was present in the operated ankle over the

whole ROM at the 11-year follow-up.

Our study confirms the results of earlier studies with short-term follow-ups,

showing that the post-operative treatment protocol after AT repair does not affect

the long-term clinical outcome or isokinetic calf muscle strength (Barfod et al.

2014, Kangas et al. 2003, Young et al. 2014). Early functional treatment with

58

weight bearing after AT repair does not increase the re-rupture rate and results in

better patient satisfaction in the short-term follow up period (Cetti et al. 1994,

Costa et al. 2003, Costa et al. 2006, Kangas et al. 2003, Kerghofss et al. 2002,

Maffulli et al. 2003, Pajala et al. 2009, Suchak et al. 2008). Additionally, early

mobilization with weight bearing may decrease the adverse effects related to cast

immobilization, including the risk of deep venous thrombosis. Therefore, we

recommend early functional treatment after AT repair.

We found that isokinetic strength changed minimally after 1 year, whereas

isometric strength recovered even 1 year later, and only a minimal deficit

remained at the last follow-up. A previous study using isometric strength as the

outcome reported up to 14.9 % deficits in men and 20.1 % deficits in women after

three years of follow-up (Leppilahti et al. 1996). Mullaney et al. (2006) reported

34 % and 20 % deficits at 20 degrees and 10 degrees of plantar flexion,

respectively, but only 6 % deficit at neutral flexion, at an average of 1.8 years

postoperatively. Pajala et al. (2009) reported a mean 10 % deficit in relative

isometric strength for the simple repair group and 2 % for the augmented repair

group at the 12-month follow-up. Therefore, isometric calf muscle strength may

take several years to recover. Different time frames for isokinetic and isometric

strength recovery should be considered when planning further ATR studies.

Furthermore, rehabilitation protocols after ATR should probably be sufficiently

aggressive during the first year after ATR to minimize strength deficits.

Several previous short-term to midterm studies of mixed operative techniques

and conservative treatment have shown 11 % to 17 % plantar flexion strength

deficits between the injured and uninjured ankles after ATR (Bevoni et al. 2014,

Leppilahti et al. 2000, Pajala et al. 2009, Rosso et al. 2013, Young et al. 2014).

Horstmann et al. (2012) reported on long-term results of AT repair and found

plantar flexion strength 6 % lower than in the uninjured leg. Our study showed

that 5 % to 8 % deficits in isokinetic strength are still present after 11 years,

despite good functional scores. However, the work-displacement curves may

represent isolated calf muscle strength better than PT or average work, and

showed deficits of up to 15 % at 25 degrees to 35 degrees plantar flexion for the

injured leg. Although ordinary patients may not notice a strength deficit of up to

15 % in plantar flexion, it may cause notable impairment for elite athletes. The

perceptual deficit that causes clinically significant impairment is not known and

further studies are needed.

59

6.4 RCT comparing surgery and conservative treatment in acute

ATRs (III)

Our results support those of earlier studies reporting that surgical and

conservative treatment of acute Achilles tendon ruptures results in similar

Achilles tendon performance scores. Surgery, however, leads to faster and better

recovery of isokinetic calf muscle strength. Surgically treated patients resulted up

to 24 % higher results both in peak torque and angle-specific peak torque at 6

months. At 18 months follow-up, the strength difference still favored surgically

treated patients, up to 14 % in peak torque and 18 % in angle specific peak torque.

Both techniques failed to restore muscle strength to that of the contralateral side.

Patient age failed to have any effect on the clinical scores, calf muscle strength, or

re-rupture rate between the treatment methods. The RAND 36-item health survey

indicated better results in the domains of physical functioning and bodily pain for

surgically treated patients, suggesting that surgery may result in better HRQoL

than conservative treatment.

In terms of Achilles tendon performance scores, our results were similar to

previous RCTs summarized in systematic reviews and meta-analyses (Holm et al.

2014, Olsson et al. 2013, Soroceanu et al. 2012). However, our re-rupture rate

after conservative treatment was higher than in some previous reports. Although

not statistically significant due to small number of patients, re-rupture rate in our

accelerated functional treatment is probably higher than in surgical treatment. A

larger study comparing accelerated rehabilitation with conventional conservative

treatment is needed to confirm our results. Nevertheless, in our study re-ruptures

were associated with noncompliance; they occurred when the Vacoped® orthosis

was off or with proper dorsiflexion injury Vacoped® orthosis on during

rehabilitation protocol. A recent meta-analysis suggested equal re-rupture rates for

surgical and non-surgical patients (risk difference 1.7 %) if functional

rehabilitation with early range of motion is performed (Soroceanu et al. 2012).

Also van der Eng et al. found no difference in the re-rupture rate or strength

differences between the surgically and conservatively treated patients followed by

early weight bearing in their meta-analysis (van der Eng et al. 2013)

The recovery of calf muscle strength after surgical and conservative treatment

has been controversial in previous studies (Keating et al. 2011, Nilsson-Helander

2010). Several recent studies showed differences favoring surgical treatment at

least in short term (Keating et al. 2011, Nilsson-Helander 2010, Olsson 2013).

Our study supports these findings and showed up to 24 % and 18 % difference

60

favoring operative treatment at 6 and 18 months, respectively. The clinical

relevance for isokinetic strength and patient satisfaction has not been studied in

the ankle joint, but isokinetic peak torque has shown good correlation to calf

muscle volume (Rosso et al. 2013). Mullanney et al. found that surgically treated

patients with isometric plantar flexion strength deficits up to 34 % and 20 % (at

20 degrees and 10 degrees of plantar flexion, respectively), were unable to

perform a decline heel rise, whereas no torque deficits from neutral to

dorsiflexion of ankle joints’ range of motion were detected (Mullaney et al.

2006). Despite up to 65 % plantar flexion strength deficit at 18 months, patients in

our study noticed the strength impairment but it did not affect their recreational

activities at 18 months. None of our patients were competitive athlete, which

probably explains the high satisfaction rate despite major calf muscle strength

impairment. Also Nilsson-Helander et al. (2010) found in their study that

objective and subjective results do not always correlate with each other. Nilsson-

Helander et al. (2010) stated that these results underscore the importance of using

objective strength tests for evaluating outcome as in the present study (Nilsson-

Helander 2010).

Optimal rehabilitation protocol in conservative treatment or after surgical

repair of acute Achilles tendon rupture remains controversial. Early motion may

encourage tendon healing and reorganization of collagen and therefore may be

critical for functional rehabilitation. Compared to previous studies with early

plantar flexion or early weight bearing, we allowed both early motion and weight

bearing (Nilsson-Helander 2010, Olsson 2013, Willits 2010). In contrast to our

results, these previous studies reported similar calf muscle strength after

conservative treatment and surgery.

Several risk factors, including tendon elongation, have been proposed as the

reason for long-term strength deficits (Kangas 2007, Mullaney 2006, Nilsson-

Helander 2010). Only Schepull et al. studied tendon elongation between non-

operative and surgical treatment, finding that tendon elongation occurred during

the first 19 weeks, but they found no difference between surgical and non-surgical

treatment (Scehpull 2013). It is possible that our expedited rehabilitation protocol

that allows early plantar flexion and full weight bearing during orthosis treatment

may result in Achilles tendon lengthening and therefore greater strength deficit in

conservative treatment. Surgery, however, may protect from tendon lengthening

during accelerated rehabilitation and restores calf muscle strength to best possible

level after the injury.

61

Choosing the optimal treatment for the patient with Achilles tendon rupture

the decision should be made individually observing patient needs and treatment

risks. Despite the treatment method major calf muscle strength deficit persist and

therefore, rehabilitation after the conservative or operative treatment may be the

most important phase that should be underlined in future studies.

Patient age had no effect on subjective or objective results when comparing

treatment methods in patients aged ≤35 and >35 years at the 18-month follow-up.

Our results suggest that patients with Achilles tendon rupture do not necessarily

need surgery. However, surgical repair may result in better calf muscle strength,

that should be considered when treating physically active and demanding patients.

Olsson et al. studied quality of life between conservatively and surgically

treated patients using the EQ-5D life quality and Foot and Ankle Outcome Score

(FAOS) questionnaires (Olsson 2013). They found no difference between the

study groups during 12 months of follow-up. In contrast, we found that surgically

treated patients achieved better results in the domains of physical functioning and

bodily pain at 18 months. The RAND 36, which produces a profile of functional

health and well-being, may be more sensitive than the EQ-5D in capturing

impairments after Achilles tendon rupture.

6.5 Clinical implications and future studies

In conclusion, our study results suggest that conservative treatment with a

functional rehabilitation protocol for Achilles tendon ruptures results in

acceptable results. Surgery and non-operative treatment of acute Achilles tendon

rupture have similar results in terms of Achilles tendon performance score, but

surgery restores calf muscle strength earlier over the entire range of motion of the

ankle joint, with 14–18 % strength difference favoring surgery at 18-months, that

should be considered when treating physically active and demanding patients.

Surgery may also result in better health-related quality of life in the domains of

physical functioning and bodily pain compared to conservative treatment

Because nonoperative treatment has largely replaced surgery in ATR, further

studies should address how more aggressive rehabilitation under physiotherapist

instruction during the first 6 months might prevent a strength deficit and whether

intensive rehabilitation in the healing period leads to increased tendon elongation.

Also clinical importance of strength deficit of ankle joint needs to be clarified.

The reason for the increasing incidence of ruptures, particularly in non-sports

related injuries, remains unclear. A registry-based study with a large number of

62

patients might provide sufficient data to compare subgroups, like men vs. women,

and the possible effects of a sedentary lifestyle and concomitant medications.

Histological and biochemical studies focused on tendon degeneration mechanisms

might also elucidate the reasons for the increasing incidence.

63

7 Conclusion

1. The incidence of Achilles tendon ruptures (ATRs) has increased significantly

in the city of Oulu during the whole time period (1979–2011) encompassed

by these studies. At least part of this increase can be explained by a growing

interest in recreational sports. The incidence in non-sports-related ruptures

has also increased steadily during whole period, but the incidence in sport-

related ruptures increased mostly during the second decade of study period.

2. Early functional treatment after operative repair of an ATR gives no

significant advantage when compared to immobilization in tension, as seen

after an 11-year follow-up. The calf muscle isokinetic strength recovers

during the first year after the injury, and minimal changes occur thereafter.

About 5 % to 8 % of the isokinetic strength deficits remain between the

ankles, but the clinical significance of this difference in strength remains

unknown. Isometric strength recovers even after the first year, and only

minimal differences remain after long-term follow-up

3. Nonoperative and operative treatment yields similar results in the Achilles

tendon performance score. Surgery, however, leads to faster and better

recovery of isokinetic calf muscle strength. The RAND 36-item health survey

also indicated better results in the domains of physical functioning and bodily

pain for surgically treated patients. Patient age has no effect on the

performance scores, strength recovery, or the RAND-36-item health survey

results.

65

References

Aalto AM, Aro AR, Teperi J - 1999 - thl.fi Aktas S, Kocaoglu B, Nalbantoglu U, Seyhan M & Guven O (2007) End-to-end versus

augmented repair in the treatment of acute Achilles tendon ruptures. J Foot Ankle Surg 46(5): 336–340.

Amlang MH, Zwipp H, Friedrich A, Peaden A, Bunk A & Rammelt S (2011) Ultrasonographic classification of achilles tendon ruptures as a rationale for individual treatment selection. ISRN Orthop 2011: 869703.

Arner O, Linholm A (1959) Subcutaneous rupture of the Achilles tendon; a study of 92 cases. Acta Chir Scand Suppl 116(Supp 239): 1–51.

Barfod KW, Bencke J, Lauridsen HB, Ban I, Ebskov L & Troelsen A (2014) Nonoperative dynamic treatment of acute achilles tendon rupture: the influence of early weight-bearing on clinical outcome: a blinded, randomized controlled trial. J Bone Joint Surg Am 96(18): 1497–1503.

Barfred T (1973) Achilles tendon rupture. Aetiology and pathogenesis of subcutaneous rupture assessed on the basis of the literature and rupture experiments on rats. Acta Orthop Scand Suppl : 3–126.

Bergman S, Feldman LS & Barkun JS (2006) Evaluating surgical outcomes. Surg Clin North Am 86(1): 129–49, x.

Beri A, Dwamena FC & Dwamena BA (2009) Association between statin therapy and tendon rupture: a case-control study. J Cardiovasc Pharmacol 53(5): 401–404.

Bevoni R, Angelini A, D’Apote G, Berti L, Fusaro I, Ellis S, Schuh R & Girolami M (2014) Long term results of acute Achilles repair with triple-bundle technique and early rehabilitation protocol. Injury 45(8): 1268–1274.

Bhandari M, Guyatt GH, Siddiqui F, Morrow F, Busse J, Leighton RK, Sprague S & Schemitsch EH (2002) Treatment of acute Achilles tendon ruptures: a systematic overview and metaanalysis. Clin Orthop Relat Res (400)(400): 190–200.

Bostick GP, Jomha NM, Suchak AA & Beaupre LA (2010) Factors associated with calf muscle endurance recovery 1 year after achilles tendon rupture repair. J Orthop Sports Phys Ther 40(6): 345–351.

Brazier JE, Harper R, Jones NM, O'Cathain A, Thomas KJ, Usherwood T & Westlake L (1992) Validating the SF-36 health survey questionnaire: new outcome measure for primary care. BMJ 305(6846): 160–164.

Brorsson A, Olsson N, Nilsson-Helander K, Karlsson J, Eriksson BI & Silbernagel KG (2015) Recovery of calf muscle endurance 3 months after an Achilles tendon rupture. Scand J Med Sci Sports .

Brown DW, Brown DR, Heath GW, Balluz L, Giles WH, Ford ES & Mokdad AH (2004) Associations between physical activity dose and health-related quality of life. Med Sci Sports Exerc 36(5): 890–896.

Brumann M, Baumbach SF, Mutschler W & Polzer H (2014) Accelerated rehabilitation following Achilles tendon repair after acute rupture - Development of an evidence-based treatment protocol. Injury 45(11): 1782–1790.

66

Buchgraber A & Passler HH (1997) Percutaneous repair of Achilles tendon rupture. Immobilization versus functional postoperative treatment. Clin Orthop Relat Res (341)(341): 113–122.

Calder JD & Saxby TS (2005) Early, active rehabilitation following mini-open repair of Achilles tendon rupture: a prospective study. Br J Sports Med 39(11): 857–859.

Cetti R, Christensen SE, Ejsted R, Jensen NM & Jorgensen U (1993) Operative versus nonoperative treatment of Achilles tendon rupture. A prospective randomized study and review of the literature. Am J Sports Med 21(6): 791–799.

Cetti R, Henriksen LO & Jacobsen KS (1994) A new treatment of ruptured Achilles tendons. A prospective randomized study. Clin Orthop Relat Res (308)(308): 155–165.

Chester R, Costa ML, Shepstone L & Donell ST (2003) Reliability of isokinetic dynamometry in assessing plantarflexion torque following Achilles tendon rupture. Foot Ankle Int 24(12): 909–915.

Christensen IB (1954) Rupture of the Achille tendon: analysis of 57 cases. Acta Chir Scand 106: 50–60.

Chun SW, Kim KE, Jang SN, Kim KI, Paik NJ, Kim KW, Jang HC & Lim JY (2013) Muscle strength is the main associated factor of physical performance in older adults with knee osteoarthritis regardless of radiographic severity. Arch Gerontol Geriatr 56(2): 377–382.

Chutkan NB (2013) Surgical versus nonsurgical treatment of acute achilles tendon rupture: a meta-analysis of randomized trials. Orthopedics 36(2): 136–137.

Claessen FM, de Vos RJ, Reijman M & Meuffels DE (2014) Predictors of primary Achilles tendon ruptures. Sports Med 44(9): 1241–1259.

Clayton RA & Court-Brown CM (2008) The epidemiology of musculoskeletal tendinous and ligamentous injuries. Injury 39(12): 1338–1344.

Copeland SA (1990) Rupture of the Achilles tendon: a new clinical test. Ann R Coll Surg Engl 72(4): 270–271.

Costa ML, MacMillan K, Halliday D, Chester R, Shepstone L, Robinson AH & Donell ST (2006) Randomised controlled trials of immediate weight-bearing mobilisation for rupture of the tendo Achillis. J Bone Joint Surg Br 88(1): 69–77.

Costa ML, Shepstone L, Darrah C, Marshall T & Donell ST (2003) Immediate full-weight-bearing mobilisation for repaired Achilles tendon ruptures: a pilot study. Injury 34(11): 874–876.

Cretnik A, Kosanovic M & Smrkolj V (2005) Percutaneous versus open repair of the ruptured Achilles tendon: a comparative study. Am J Sports Med 33(9): 1369–1379.

Cretnik A, Kosir R & Kosanovic M (2010) Incidence and outcome of operatively treated achilles tendon rupture in the elderly. Foot Ankle Int 31(1): 14–18.

Cummins EJ, Anson BJ (1946) The structure of the calcaneal tendon (of Achilles) in relation to orthopedic surgery, with additional observations on the plantaris muscle. Surg Gynecol Obstet 83: 107–116.

Cuttica DJ, Hyer CF & Berlet GC (2015) Intraoperative value of the thompson test. J Foot Ankle Surg 54(1): 99–101.

67

Davis JJ, Mason KT & Clark DA (1999) Achilles tendon ruptures stratified by age, race, and cause of injury among active duty U.S. Military members. Mil Med 164(12): 872–873.

de Oliveira LP, Vieira CP, Guerra FD, Almeida MS & Pimentel ER (2015) Structural and biomechanical changes in the Achilles tendon after chronic treatment with statins. Food Chem Toxicol 77: 50–57.

Del Buono A, Chan O & Maffulli N (2012) Achilles tendon: functional anatomy and novel emerging models of imaging classification. Int Orthop .

Don R, Ranavolo A, Cacchio A, Serrao M, Costabile F, Iachelli M, Camerota F, Frascarelli M & Santilli V (2007) Relationship between recovery of calf-muscle biomechanical properties and gait pattern following surgery for achilles tendon rupture. Clin Biomech (Bristol, Avon) 22(2): 211–220.

Fox JM, Blazina ME, Jobe FW, Kerlan RK, Carter VS, Shields CL,Jr & Carlson GJ (1975) Degeneration and rupture of the Achilles tendon. Clin Orthop Relat Res (107)(107): 221–224.

Ganestam A, Kallemose T, Troelsen A & Barfod KW (2015) Increasing incidence of acute Achilles tendon rupture and a noticeable decline in surgical treatment from 1994 to 2013. A nationwide registry study of 33 160 patients. Knee Surg Sports Traumatol Arthrosc .

Garras DN, Raikin SM, Bhat SB, Taweel N & Karanjia H (2012) MRI is unnecessary for diagnosing acute Achilles tendon ruptures: clinical diagnostic criteria. Clin Orthop Relat Res 470(8): 2268–2273.

Garrick JG (2012) Does accelerated functional rehabilitation after surgery improve outcomes in patients with acute achilles tendon ruptures? Clin J Sport Med 22(4): 379–380.

Gerdes MH, Brown TD, Bell AL, Baker JA, Levson M & Layer S (1992) A flap augmentation technique for Achilles tendon repair. Postoperative strength and functional outcome. Clin Orthop Relat Res (280)(280): 241–246.

Gigante A, Moschini A, Verdenelli A, Del Torto M, Ulisse S & de Palma L (2008) Open versus percutaneous repair in the treatment of acute Achilles tendon rupture: a randomized prospective study. Knee Surg Sports Traumatol Arthrosc 16(2): 204–209.

Gillies H & Chalmers J (1970) The management of fresh ruptures of the tendo achillis. J Bone Joint Surg Am 52(2): 337–343.

Gwynne-Jones DP, Sims M & Handcock D (2011) Epidemiology and outcomes of acute Achilles tendon rupture with operative or nonoperative treatment using an identical functional bracing protocol. Foot Ankle Int 32(4): 337–343.

Hohendorff B, Siepen W, Spiering L, Staub L, Schmuck T & Boss A (2008) Long-term results after operatively treated Achilles tendon rupture: fibrin glue versus suture. J Foot Ankle Surg 47(5): 392–399.

Holm C, Kjaer M & Eliasson P (2014) Achilles tendon rupture - treatment and complications: A systematic review. Scand J Med Sci Sports .

Horstmann T, Lukas C, Merk J, Brauner T & Mundermann A (2012) Deficits 10-years after Achilles tendon repair. Int J Sports Med 33(6): 474–479.

68

Houshian S, Tscherning T & Riegels-Nielsen P (1998) The epidemiology of Achilles tendon rupture in a Danish county. Injury 29(9): 651–654.

Huang J, Wang C, Ma X, Wang X, Zhang C & Chen L (2015) Rehabilitation regimen after surgical treatment of acute Achilles tendon ruptures: a systematic review with meta-analysis. Am J Sports Med 43(4): 1008–1016.

Hufner TM, Brandes DB, Thermann H, Richter M, Knobloch K & Krettek C (2006) Long-term results after functional nonoperative treatment of achilles tendon rupture. Foot Ankle Int 27(3): 167–171.

Hurme T, Lehto M, Kalimo H, Kannus P & Järvinen M (1990) Sequence of changes in fibre size and type in muscle immobilized at various lengths. J Sports Traumatol Rel Res 2:77–85.

Huttunen TT, Kannus P, Rolf C, Fellander-Tsai L & Mattila VM (2014) Acute Achilles Tendon Ruptures: Incidence of Injury and Surgery in Sweden Between 2001 and 2012. Am J Sports Med .

Inglis AE, Scott WN, Sculco TP & Patterson AH (1976) Ruptures of the tendo achillis. An objective assessment of surgical and non-surgical treatment. J Bone Joint Surg Am 58(7): 990–993.

Jacobs D, Martens M, Van Audekercke R, Mulier JC & Mulier F (1978) Comparison of conservative and operative treatment of Achilles tendon rupture. Am J Sports Med 6(3): 107–111.

Jarvinen TA, Kannus P, Maffulli N & Khan KM (2005) Achilles tendon disorders: etiology and epidemiology. Foot Ankle Clin 10(2): 255–266.

Jessing P & Hansen E (1975) Surgical treatment of 102 tendo achillis ruptures-- suture or tenontoplasty? Acta Chir Scand 141(5): 370–377.

Jessing P & Hansen E (1975) Surgical treatment of 102 tendo achillis ruptures-- suture or tenontoplasty? Acta Chir Scand 141(5): 370–377.

Jiang N, Wang B, Chen A, Dong F & Yu B (2012) Operative versus nonoperative treatment for acute Achilles tendon rupture: a meta-analysis based on current evidence. Int Orthop 36(4): 765–773.

Jones MP, Khan RJ & Carey Smith RL (2012) Surgical interventions for treating acute achilles tendon rupture: key findings from a recent cochrane review. J Bone Joint Surg Am 94(12): e88.

Jozsa L, Kvist M, Balint BJ, Reffy A, Jarvinen M, Lehto M & Barzo M (1989) The role of recreational sport activity in Achilles tendon rupture. A clinical, pathoanatomical, and sociological study of 292 cases. Am J Sports Med 17(3): 338–343.

Kager H (1939) Zur Klinik und Diagnostik des Achillessehnenrisses. Chirurg 11:691–695. Kangas J, Pajala A, Ohtonen P & Leppilahti J (2007) Achilles tendon elongation after

rupture repair: a randomized comparison of 2 postoperative regimens. Am J Sports Med 35(1): 59–64.

Kangas J, Pajala A, Siira P, Hamalainen M & Leppilahti J (2003) Early functional treatment versus early immobilization in tension of the musculotendinous unit after Achilles rupture repair: a prospective, randomized, clinical study. J Trauma 54(6): 1171–80; discussion 1180-1.

69

Kannus P & Jozsa L (1991) Histopathological changes preceding spontaneous rupture of a tendon. A controlled study of 891 patients. J Bone Joint Surg Am 73(10): 1507–1525.

Karjalainen PT, Aronen HJ, Pihlajamaki HK, Soila K, Paavonen T & Bostman OM (1997) Magnetic resonance imaging during healing of surgically repaired Achilles tendon ruptures. Am J Sports Med 25(2): 164–171.

Karpakka J (1991) Effects of physical activity and inactivity on collagen synthesis in rat skeletal muscle and tendon. Thesis. Acta Universitas Ouluensis. Series D, Medica 231. Oulu University, Finland.

Kayser R, Mahlfeld K & Heyde CE (2005) Partial rupture of the proximal Achilles tendon: a differential diagnostic problem in ultrasound imaging. Br J Sports Med 39(11): 838-42; discussion 838–42.

Kearney RS, Achten J, Lamb SE, Plant C & Costa ML (2012) A systematic review of patient-reported outcome measures used to assess Achilles tendon rupture management: what's being used and should we be using it? Br J Sports Med 46(16): 1102–1109.

Kearney RS, McGuinness KR, Achten J & Costa ML (2012) A systematic review of early rehabilitation methods following a rupture of the Achilles tendon. Physiotherapy 98(1): 24–32.

Keating JF & Will EM (2011) Operative versus non-operative treatment of acute rupture of tendo Achillis: a prospective randomised evaluation of functional outcome. J Bone Joint Surg Br 93(8): 1071–1078.

Keene JS, Lash EG, Fisher DR & De Smet AA (1989) Magnetic resonance imaging of Achilles tendon ruptures. Am J Sports Med 17(3): 333–337.

Kerkhoffs GM, Struijs PA, Raaymakers EL & Marti RK (2002) Functional treatment after surgical repair of acute Achilles tendon rupture: wrap vs walking cast. Arch Orthop Trauma Surg 122(2): 102–105.

Khan RJ, Fick D, Keogh A, Crawford J, Brammar T & Parker M (2005) Treatment of acute achilles tendon ruptures. A meta-analysis of randomized, controlled trials. J Bone Joint Surg Am 87(10): 2202–2210.

Kim KM, Chun KC, Hwang JS & Chun CH (2013) Mid-term Results of Single-Radius Cruciate Retaining Total Knee Arthroplasty: Minimum 5 Year Follow-up. Knee Surg Relat Res 25(4): 174–179.

Komi PV, Fukashiro S & Jarvinen M (1992) Biomechanical loading of Achilles tendon during normal locomotion. Clin Sports Med 11(3): 521–531.

Krackow KA, Thomas SC & Jones LC (1986) A new stitch for ligament-tendon fixation. Brief note. J Bone Joint Surg Am 68(5): 764–766.

Kvist M (1991) Achilles tendon injuries in athletes. Ann Chir Gynaecol 80(2): 188–201. Lagergren C & Lindholm A (1959) Vascular distribution in the Achilles tendon; an

angiographic and microangiographic study. Acta Chir Scand 116(5–6): 491–495. Laseter JT & Russell JA (1991) Anabolic steroid-induced tendon pathology: a review of

the literature. Med Sci Sports Exerc 23(1): 1–3. Lea RB & Smith L (1968) Rupture of the achilles tendon. Nonsurgical treatment. Clin

Orthop Relat Res 60: 115–118.

70

Lee SJ, Goldsmith S, Nicholas SJ, McHugh M, Kremenic I & Ben-Avi S (2008) Optimizing Achilles tendon repair: effect of epitendinous suture augmentation on the strength of achilles tendon repairs. Foot Ankle Int 29(4): 427–432.

Leitner A, Muller A, Voigt C & Rahmanzadeh R (1991) Modified after care following primary management of rupture of the Achilles tendon. Aktuelle Traumatol 21(6): 285–292.

Leppilahti J & Orava S (1998) Total Achilles tendon rupture. A review. Sports Med 25(2): 79–100.

Leppilahti J, Forsman K, Puranen J & Orava S (1998) Outcome and prognostic factors of achilles rupture repair using a new scoring method. Clin Orthop Relat Res (346)(346): 152–161.

Leppilahti J, Lahde S, Forsman K, Kangas J, Kauranen K & Orava S (2000) Relationship between calf muscle size and strength after achilles rupture repair. Foot Ankle Int 21(4): 330–335.

Leppilahti J, Puranen J & Orava S (1996) Incidence of Achilles tendon rupture. Acta Orthop Scand 67(3): 277–279.

Leppilahti J, Siira P, Vanharanta H & Orava S (1996) Isokinetic evaluation of calf muscle performance after Achilles rupture repair. Int J Sports Med 17(8): 619–623.

Levi N (1997) The incidence of Achilles tendon rupture in Copenhagen. Injury 28(4): 311–313.

Lim J, Dalal R & Waseem M (2001) Percutaneous vs. open repair of the ruptured Achilles tendon--a prospective randomized controlled study. Foot Ankle Int 22(7): 559–568.

Lindholm A (1959) A new method of operation in subcutaneous rupture of the Achilles tendon. Acta Chir Scand 117: 261–270.

Lipscomb PR & Weiner AD (1956) Rupture of muscles and tendons. Minn Med 39(11): 731–736.

Ljungqvist R (1967) Subcutaneous partial rupture of the Achilles tendon. Acta Orthop Scand : Suppl 113:1+.

Ma GW & Griffith TG (1977) Percutaneous repair of acute closed ruptured achilles tendon: a new technique. Clin Orthop Relat Res (128)(128): 247–255.

Maffulli N (1998) The clinical diagnosis of subcutaneous tear of the Achilles tendon. A prospective study in 174 patients. Am J Sports Med 26(2): 266–270.

Maffulli N (2005) Augmented repair of acute Achilles tendon ruptures using gastrocnemius-soleus fascia. Int Orthop 29(2): 134.

Maffulli N, Del Buono A, Spiezia F, Maffulli GD, Longo UG & Denaro V (2013) Less-invasive semitendinosus tendon graft augmentation for the reconstruction of chronic tears of the Achilles tendon. Am J Sports Med 41(4): 865–871.

Maffulli N, Tallon C, Wong J, Lim KP & Bleakney R (2003) Early weightbearing and ankle mobilization after open repair of acute midsubstance tears of the achilles tendon. Am J Sports Med 31(5): 692–700.

Maffulli N, Thorpe AP & Smith EW (2001) Magnetic resonance imaging after operative repair of achilles tendon rupture. Scand J Med Sci Sports 11(3): 156–162.

71

Maffulli N, Waterston SW, Squair J, Reaper J & Douglas AS (1999) Changing incidence of Achilles tendon rupture in Scotland: a 15-year study. Clin J Sport Med 9(3): 157–160.

Majewski M, Schaeren S, Kohlhaas U & Ochsner PE (2008) Postoperative rehabilitation after percutaneous Achilles tendon repair: early functional therapy versus cast immobilization. Disabil Rehabil 30(20–22): 1726–1732.

Mandelbaum BR, Myerson MS & Forster R (1995) Achilles tendon ruptures. A new method of repair, early range of motion, and functional rehabilitation. Am J Sports Med 23(4): 392–395.

Marie I, Delafenetre H, Massy N, Thuillez C, Noblet C & Network of the French Pharmacovigilance Centers (2008) Tendinous disorders attributed to statins: a study on ninety-six spontaneous reports in the period 1990–2005 and review of the literature. Arthritis Rheum 59(3): 367–372.

Mark-Christensen T, Troelsen A, Kallemose T & Barfod KW (2014) Functional rehabilitation of patients with acute Achilles tendon rupture: a meta-analysis of current evidence. Knee Surg Sports Traumatol Arthrosc .

Mattila VM, Huttunen TT, Haapasalo H, Sillanpaa P, Malmivaara A & Pihlajamaki H (2015) Declining incidence of surgery for Achilles tendon rupture follows publication of major RCTs: evidence-influenced change evident using the Finnish registry study. Br J Sports Med 49(16): 1084–1086.

McComis GP, Nawoczenski DA & DeHaven KE (1997) Functional bracing for rupture of the Achilles tendon. Clinical results and analysis of ground-reaction forces and temporal data. J Bone Joint Surg Am 79(12): 1799–1808.

McCormack R & Bovard J (2015) Early functional rehabilitation or cast immobilisation for the postoperative management of acute Achilles tendon rupture? A systematic review and meta-analysis of randomised controlled trials. Br J Sports Med 49(20): 1329–1335.

Metz R, van der Heijden GJ, Verleisdonk EJ, Andrlik M & van der Werken C (2011) Persistent disability despite sufficient calf muscle strength after rerupture of surgically treated acute achilles tendon ruptures. Foot Ankle Spec 4(2): 77–81.

Metz R, Verleisdonk EJ, van der Heijden GJ, Clevers GJ, Hammacher ER, Verhofstad MH & van der Werken C (2008) Acute Achilles tendon rupture: minimally invasive surgery versus nonoperative treatment with immediate full weightbearing--a randomized controlled trial. Am J Sports Med 36(9): 1688–1694.

Moller A, Astron M & Westlin N (1996) Increasing incidence of Achilles tendon rupture. Acta Orthop Scand 67(5): 479–481.

Moller M, Movin T, Granhed H, Lind K, Faxen E & Karlsson J (2001) Acute rupture of tendon Achillis. A prospective randomised study of comparison between surgical and non-surgical treatment. J Bone Joint Surg Br 83(6): 843–848.

Mullaney MJ, McHugh MP, Tyler TF, Nicholas SJ & Lee SJ (2006) Weakness in end-range plantar flexion after Achilles tendon repair. Am J Sports Med 34(7): 1120–1125.

Munteanu SE & Barton CJ (2011) Lower limb biomechanics during running in individuals with achilles tendinopathy: a systematic review. J Foot Ankle Res 4: 15-1146-4-15.

72

Nada A (1985) Rupture of the calcaneal tendon. Treatment by external fixation. J Bone Joint Surg Br 67(3): 449–453.

Neumayer F, Mouhsine E, Arlettaz Y, Gremion G, Wettstein M & Crevoisier X (2010) A new conservative-dynamic treatment for the acute ruptured Achilles tendon. Arch Orthop Trauma Surg 130(3): 363–368.

Nillius SA, Nilsson BE & Westlin NE (1976) The incidence of Achilles tendon rupture. Acta Orthop Scand 47:118–121.

Nilsson-Helander K, Silbernagel KG, Thomee R, Faxen E, Olsson N, Eriksson BI & Karlsson J (2010) Acute achilles tendon rupture: a randomized, controlled study comparing surgical and nonsurgical treatments using validated outcome measures. Am J Sports Med 38(11): 2186–2193.

Nistor L (1981) Surgical and non-surgical treatment of Achilles Tendon rupture. A prospective randomized study. J Bone Joint Surg Am 63(3): 394–399.

Nyyssonen T, Luthje P & Kroger H (2008) The increasing incidence and difference in sex distribution of Achilles tendon rupture in Finland in 1987–1999. Scand J Surg 97(3): 272–275.

Nyyssonen T, Saarikoski H, Kaukonen JP, Luthje P & Hakovirta H (2003) Simple end-to-end suture versus augmented repair in acute Achilles tendon ruptures: a retrospective comparison in 98 patients. Acta Orthop Scand 74(2): 206–208.

O'Brien M (1992) Functional anatomy and physiology of tendons. Clin Sports Med 11(3): 505–520.

O'Brien T (1984) The needle test for complete rupture of the Achilles tendon. J Bone Joint Surg Am 66(7): 1099–1101.

Olsson N, Nilsson-Helander K, Karlsson J, Eriksson BI, Thomee R, Faxen E & Silbernagel KG (2011) Major functional deficits persist 2 years after acute Achilles tendon rupture. Knee Surg Sports Traumatol Arthrosc 19(8): 1385–1393.

Olsson N, Petzold M, Brorsson A, Karlsson J, Eriksson BI & Gravare Silbernagel K (2014) Predictors of Clinical Outcome After Acute Achilles Tendon Ruptures. Am J Sports Med .

Olsson N, Silbernagel KG, Eriksson BI, Sansone M, Brorsson A, Nilsson-Helander K & Karlsson J (2013) Stable Surgical Repair With Accelerated Rehabilitation Versus Nonsurgical Treatment for Acute Achilles Tendon Ruptures: A Randomized Controlled Study. Am J Sports Med .

Pajala A, Kangas J, Ohtonen P & Leppilahti J (2002) Rerupture and deep infection following treatment of total Achilles tendon rupture. J Bone Joint Surg Am 84-A(11): 2016–2021.

Pajala A, Kangas J, Siira P, Ohtonen P & Leppilahti J (2009) Augmented compared with nonaugmented surgical repair of a fresh total Achilles tendon rupture. A prospective randomized study. J Bone Joint Surg Am 91(5): 1092–1100.

73

Petersen OF, Nielsen MB, Jensen KH & Solgaard S (2002) Randomized comparison of CAM walker and light-weight plaster cast in the treatment of first-time Achilles tendon rupture. Ugeskr Laeger 164(33): 3852–3855.Porter DA, Barnes AF, Rund AM, Kaz AJ, Tyndall JA, Millis AA (2014) Acute Achilles tendon repair: strength outcomes after an acute bout of exercise in recreational athletes. Fott Ankle Int. 35(2): 123-130

Raikin SM, Garras DN & Krapchev PV (2013) Achilles tendon injuries in a United States population. Foot Ankle Int 34(4): 475–480.

Rantanen J, Hurme T & Paananen M (1993) Immobilization in neutral versus equinus position after Achilles tendon repair. A review of 32 patients. Acta Orthop Scand 64(3): 333–335.

Rosager S, Aagaard P, Dyhre-Poulsen P, Neergaard K, Kjaer M & Magnusson SP (2002) Load-displacement properties of the human triceps surae aponeurosis and tendon in runners and non-runners. Scand J Med Sci Sports 12(2): 90–98.

Rosso C, Buckland DM, Polzer C, Sadoghi P, Schuh R, Weisskopf L, Vavken P & Valderrabano V (2013) Long-term biomechanical outcomes after Achilles tendon ruptures. Knee Surg Sports Traumatol Arthrosc .

Rosso C, Vavken P, Polzer C, Buckland DM, Studler U, Weisskopf L, Lottenbach M, Muller AM & Valderrabano V (2013) Long-term outcomes of muscle volume and Achilles tendon length after Achilles tendon ruptures. Knee Surg Sports Traumatol Arthrosc .

Ruhdorfer A, Wirth W & Eckstein F (2015) Relationship between isometric thigh muscle strength and minimum clinically important differences in knee function in osteoarthritis: data from the osteoarthritis initiative. Arthritis Care Res (Hoboken) 67(4): 509–518.

Saleh M, Marshall PD, Senior R & MacFarlane A (1992) The Sheffield splint for controlled early mobilisation after rupture of the calcaneal tendon. A prospective, randomised comparison with plaster treatment. J Bone Joint Surg Br 74(2): 206–209.

Schepull T & Aspenberg P (2013) Early controlled tension improves the material properties of healing human achilles tendons after ruptures: a randomized trial. Am J Sports Med 41(11): 2550–2557.

Schroeder D, Lehmann M, Steinbrueck K (1997) Treatment of acute Achilles tendon ruptures: open vs. percutaneous repair vs conservative treatment. A prospective randomized study Orthop trans 21:1228

Scott A, Grewal N & Guy P (2014) The seasonal variation of Achilles tendon ruptures in Vancouver, Canada: a retrospective study. BMJ Open 4(2): e004320-2013-004320.

Seymour RJ & Bacharach DW (1990) The effect of position and speed on ankle plantarflexion in females. J Orthop Sports Phys Ther 12(4): 153–156.

Silbernagel KG, Steele R & Manal K (2012) Deficits in heel-rise height and achilles tendon elongation occur in patients recovering from an Achilles tendon rupture. Am J Sports Med 40(7): 1564–1571.

Silfverskiöld N (1941) Über die subkutane totale Achillessehnenruptur und deren Behandlung. Acta Chir Scand 84:393–413.

74

Sode J, Obel N, Hallas J & Lassen A (2007) Use of fluroquinolone and risk of Achilles tendon rupture: a population-based cohort study. Eur J Clin Pharmacol 63(5): 499–503.

Soroceanu A, Sidhwa F, Aarabi S, Kaufman A & Glazebrook M (2012) Surgical versus nonsurgical treatment of acute Achilles tendon rupture: a meta-analysis of randomized trials. J Bone Joint Surg Am 94(23): 2136–2143.

Spoendlin J, Meier C, Jick SS & Meier CR (2015) Oral and inhaled glucocorticoid use and risk of Achilles or biceps tendon rupture: a population-based case-control study. Ann Med 47(6): 492–498.

Stanish WD, Curwin S & Rubinovich M (1985) Tendinitis: the analysis and treatment for running. Clin Sports Med 4(4): 593–609.

Stein V, Laprell H, Tinnemeyer S & Petersen W (2000) Quantitative assessment of intravascular volume of the human Achilles tendon. Acta Orthop Scand 71(1): 60–63.

Suchak AA, Bostick G, Reid D, Blitz S & Jomha N (2005) The incidence of Achilles tendon ruptures in Edmonton, Canada. Foot Ankle Int 26(11): 932–936.

Suchak AA, Bostick GP, Beaupre LA, Durand DC & Jomha NM (2008) The influence of early weight-bearing compared with non-weight-bearing after surgical repair of the Achilles tendon. J Bone Joint Surg Am 90(9): 1876–1883.

Tezeren G & Kuru I (2006) Augmentation vs Nonaugmentation Techniques for Open Repairs of Achilles Tendon Ruptures with Early Functional Treatment: A Prospective Randomized Study. J Sports Sci Med 5(4): 607–614.

Thermann H, Frerichs O, Biewener A, Krettek C & Schandelmaier P (1995) Biomechanical studies of human Achilles tendon rupture. Unfallchirurg 98(11): 570–575.

Thermann H, Zwipp H & Tscherne H (1995) Functional treatment concept of acute rupture of the Achilles tendon. 2 years results of a prospective randomized study. Unfallchirurg 98(1): 21–32.

Thermann H, Zwipp H, Milbradt H & Reimer P (1989) Ultrasound sonography in the diagnosis and follow-up of Achilles tendon rupture. Unfallchirurg 92(6): 266–273.

Thompson TC & Doherty JH (1962) Spontaneous rupture of tendon of Achilles: a new clinical diagnostic test. J Trauma 2: 126–129.

Turmo-Garuz A, Rodas G, Balius R, Til L, Miguel-Perez M, Pedret C, Del Buono A & Maffulli N (2014) Can local corticosteroid injection in the retrocalcaneal bursa lead to rupture of the Achilles tendon and the medial head of the gastrocnemius muscle? Musculoskelet Surg 98(2): 121–126.

Twaddle BC & Poon P (2007) Early motion for Achilles tendon ruptures: is surgery important? A randomized, prospective study. Am J Sports Med 35(12): 2033–2038.

van der Eng DM, Schepers T, Goslings JC & Schep NW (2013) Rerupture Rate after Early Weightbearing in Operative Versus Conservative Treatment of Achilles Tendon Ruptures: A Meta-analysis. J Foot Ankle Surg 52(5): 622–628.

van Sterkenburg MN & van Dijk CN (2011) Injection treatment for chronic midportion Achilles tendinopathy: do we need that many alternatives? Knee Surg Sports Traumatol Arthrosc 19(4): 513–515.

75

Wählby L (1978) Achilles tendon injury: Aspectson muscle structure and strength. Thesis No 38. Umeå University, Sweden

Waldecker U, Hofmann G & Drewitz S (2012) Epidemiologic investigation of 1394 feet: coincidence of hindfoot malalignment and Achilles tendon disorders. Foot Ankle Surg 18(2): 119–123.

Wallace RG, Heyes GJ & Michael AL (2011) The non-operative functional management of patients with a rupture of the tendo Achillis leads to low rates of re-rupture. J Bone Joint Surg Br 93(10): 1362–1366.

Wallace RG, Traynor IE, Kernohan WG & Eames MH (2004) Combined conservative and orthotic management of acute ruptures of the Achilles tendon. J Bone Joint Surg Am 86-A(6): 1198–1202.

Walz M, Cramer J, Mollenhoff G & Muhr G (1993) Ultrasonographic monitoring of conservative-functional treatment of rupture of the Achilles tendon. Orthopade 22(5): 317–322.

Webber SC & Porter MM (2010) Reliability of ankle isometric, isotonic, and isokinetic strength and power testing in older women. Phys Ther 90(8): 1165–1175.

White DW, Wenke JC, Mosely DS, Mountcastle SB & Basamania CJ (2007) Incidence of major tendon ruptures and anterior cruciate ligament tears in US Army soldiers. Am J Sports Med 35(8): 1308–1314.

Wilkins R & Bisson LJ (2012) Operative versus nonoperative management of acute Achilles tendon ruptures: a quantitative systematic review of randomized controlled trials. Am J Sports Med 40(9): 2154–2160.

Willits K, Amendola A, Bryant D, Mohtadi NG, Giffin JR, Fowler P, Kean CO & Kirkley A (2010) Operative versus nonoperative treatment of acute Achilles tendon ruptures: a multicenter randomized trial using accelerated functional rehabilitation. J Bone Joint Surg Am 92(17): 2767–2775.

Wills CA, Washburn S, Caiozzo V & Prietto CA (1986) Achilles tendon rupture. A review of the literature comparing surgical versus nonsurgical treatment. Clin Orthop Relat Res (207)(207): 156–163.

Wong J, Barrass V & Maffulli N (2002) Quantitative review of operative and nonoperative management of achilles tendon ruptures. Am J Sports Med 30(4): 565–575.

Young SW, Patel A, Zhu M, van Dijck S, McNair P, Bevan WP & Tomlinson M (2014) Weight-Bearing in the Nonoperative Treatment of Acute Achilles Tendon Ruptures: A Randomized Controlled Trial. J Bone Joint Surg Am 96(13): 1073–1079.

Zwipp H, Sudkamp N, Thermann H & Samek N (1989) Rupture of the Achilles tendon. Results of 10 years' follow-up after surgical treatment. A retrospective study. Unfallchirurg 92(11): 554–559.

77

Appendices

Appendix 1 Leppilahti Score ........................................................................... 78

Appendix 2 Strength measurements ................................................................. 82

78

Appendix 1 Leppilahti Score

Pain (15 points)

None 15

Mild, no limitations on recreational activities 10

Moderate, limitations on recreational but not daily activities 5

Severe, limitations on recreational and daily activities 0

Stiffness (15 points)

None 15

Mild, occasional, no limitations on recreational activities 10



Subjective calf muscle weakness (15 points)

None 15

Mild, no limitations on recreational activities 10



Footwear restrictions (10 points)

None 10

Mild, most shoes tolerated 5

Moderate, unable to tolerate fashionable shoes, modified shoes tolerated 0

Active range-of-motion difference between ankles (15 points)

Normal (5 deg) 15

Mild (6–10 deg) 10

Moderate (11–15 deg) 5

Severe (16 deg) 0

79

Subjective result (15 points)

Very satisfied 15

Satisfied with minor reservations 10

Satisfied with major reservations 5

Dissatisfied 0

Isokinetic muscle strength score (15 points)

Excellent 15

Good 10

Fair 5

Poor 0

Maximum possible total 100

At least 90 points excellent,

75–89 points good,

60–74 points fair and

60 points poor

80

Isokinetic Ankle Strength Scale for Scoring

Plantar Flexion and Dorsiflexion Peak Torques of the Ankle at Three Test Speeds

(60, 120, and 180 deg/s)

Plantar flexion peak torque 60 deg/s percentage difference (uninjured-

injured) (17 points)

≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0

Dorsiflexion peak torque 60 deg/s percentage difference (17 points)

≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0

Plantar flexion peak torque 120 deg/s percentage difference (17 points)

≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0

81


≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0

Plantar flexion peak torque 180 deg/s percentage difference (17 points)

≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0


≤ 2 % 17

> 2 ≤ 5 % 15

> 5 ≤ 10 % 13

> 10 ≤ 25 % 9

> 25 ≤ 50 % 5

> 50 % 0

Maximum possible total 102

82

Appendix 2 Strength measurements

Strength measurements study II

The isokinetic and isometric strength of both ankles were assessed 3, 6, and 14

months and 11 years after surgery. A physiotherapist performed all strength

measurements using a computer-based isokinetic dynamometer (Lido Multi-Joint

2, Loredan Biomedical, Inc., West Sacramento, CA). Patients were informed of

the measurement procedure. A 10-minute warm-up period of ergometer cycling

was included before the test. The test was performed with the patient in the supine

position, and the patient was fixed to the testing apparatus with straps around the

foot and pelvis, with the knee supported in extension. The extent of ankle motion

was from 15 degrees of dorsiflexion to 35 degrees of plantar flexion. Before

testing, the patient performed a few submaximal and maximal repetitions of the

ankle flexion and extension movements at the isokinetic test velocity. The

isokinetic plantar flexion strengths were measured; first at a speed of 60

degrees/s, then at 120 degrees/s, and finally at 180 degrees/s after 2 minutes of

rest. Five maximal voluntary muscular torque contractions were required. After

the isokinetic tests, the maximal isometric plantar flexion strength was measured

with the ankle in the neutral position. The peak torque, average work and

isometric strength results were measured for both legs

The groups were compared using the unaffected ankle as a reference. The

relative deficit ([unaffected − affected side]/ unaffected side x 100 %) in peak

torque, average work, and isometric strength was calculated. The injured and non-

injured sides were compared using absolute values of peak torque and average

work. Average work (measured in joules) was defined as the sum of the total area

under all of the torque-angular displacement (time) plots and was measured as the

mean of the 5 best repetitions of the test. Additionally, for the 11-year control, the

repetition with the highest plantar flexion peak torque value was selected and

work-displacement curves (−15 degrees to 35 degrees) for both calves were

calculated to assess the work deficits for each 10-degree interval over the range-

of-motion of the ankle joint.

83

Strength measurements study III

An experienced physiotherapist and an exercise physiologist performed strength

measurements using a computer-based isokinetic dynamometer (Con-Trex

biomechanical test and training system, CMV AG Duebendorf, Switzerland). The

patients were informed of the measurement procedure before testing. Ergometer

cycling was performed during a 10-minute warm-up period with a few

submaximal and maximal repetitions of ankle flexion and extension movements

at the isokinetic test velocity. During testing, the patient was in the supine

position with the knee supported in extension. The extent of ankle motion was

from 15° dorsiflexion to 35° plantar flexion. The isokinetic plantar flexion

strengths of both ankles were measured at speeds of 60, 120, and 180 degrees/s.

Five maximal voluntary muscular torque contractions were required.

Peak plantar flexion torque at an angular velocity of 60 degrees/s was

recorded for each leg based on the best repetition. To assess angle specific peak

torque deficits over the ankle joint’s range of motion, peak torque values at

specific angles (0°, 10°, and 20°) were recorded based on the five repetitions for

both calves. Intraclass correlation for angle specific peak torque was high (0.81–

0.9 ICC).

Study III strength measurement knee in extension

85

Original publications

I Lantto I, Heikkinen J, Flinkkilä T, Ohtonen P, Leppilahti J (2014) Epidemiology of Achilles tendon ruptures: increasing incidence over a 33-year period. Scand J Med Sci Sports. 25(1):e133-8.

II Lantto I, Heikkinen J, Flinkkilä T, Ohtonen P, Kangas J, Siira P, Leppilahti J (2015) Early Functional Treatment Versus Cast Immobilization in Tension After Achilles Rupture Repair: Results of a Prospective Randomized Trial With 10 or More Years of Follow-up. Am J Sports Med. Sep;43(9):2302-9

III Lantto I, Heikkinen J, Siira P, Laine V, Flinkkilä T, Ohtonen P, Leppilahti J (2015) A prospective randomized trial comparing surgery and conservative treatment in acute Achilles tendon ruptures. Surgery restores strength better, subjective results similar. Am J Sports Med, in press.

Reprinted with permission from John Wiley & Sons publications (I) and with

permission from SAGE publications (II, III)

Original publications are not included in the electronic version of the dissertation.


Book orders:Granum: Virtual book storehttp://granum.uta.fi/granum/

S E R I E S D M E D I C A

1344. Jukuri, Tuomas (2016) Resting state brain networks in young people with familialrisk for psychosis

1345. Päkkilä, Fanni (2016) Thyroid function of mother and child and their impact onthe child’s neuropsychological development

1346. Löppönen, Pekka (2016) Preceding medication, inflammation, and hematomaevacuation predict outcome of intracerebral hemorrhage : a population basedstudy

1347. Kokkonen, Tuomo (2016) Endothelial FasL in lymph nodes and in intestinallymphatic tissue

1348. Rytty, Riikka (2016) Resting-state functional MRI in behavioral variant offrontotemporal dementia

1349. Kelempisioti, Anthi (2016) Genetic risk factors for intervertebral discdegeneration

1350. Nätynki, Marjut (2016) Venous malformation causative mutations affect TIE2receptor trafficking, downstream signaling and vascular endothelial cell functions

1351. Ruotsalainen, Heidi (2016) Elintapaohjausinterventioiden vaikuttavuusylipainoisten ja lihavien nuorten fyysiseen aktiivisuuteen ja elintapamuutokseensitoutumiseen

1352. Tuisku, Anna (2016) Tobacco and health : A study of young adults in NorthernFinland

1353. Forsman, Minna (2016) Histological characteristics and gene expression profilingof Dupuytren’s disease

1354. Moilanen, Jyri (2016) Functional analysis of collagen XVII in epithelial cancers anda mouse model

1355. Selkälä, Eija (2016) Role of α-methylacyl-CoA racemase in lipid metabolism

1356. Ohukainen, Pauli (2016) Molecular profiling of calcific aortic valve disease

1357. Oikarinen, Anne (2016) Effects of risk factor targeted lifestyle counsellingintervention on quality of lifestyle counselling and on adherence to lifestylechange in stroke patients

1358. Rannikko, Irina (2016) Change in cognitive performance and its predictors ingeneral population and schizophrenia in early midlife : The Northern Finland BirthCohort 1966 Study

UNIVERSITY OF OULU P .O. Box 8000 F I -90014 UNIVERSITY OF OULU FINLAND


Professor Esa Hohtola

University Lecturer Santeri Palviainen

Postdoctoral research fellow Sanna Taskila


University Lecturer Veli-Matti Ulvinen

Director Sinikka Eskelinen

Professor Jari Juga

University Lecturer Anu Soikkeli


Publications Editor Kirsti Nurkkala

ISBN 978-952-62-1197-8 (Paperback)ISBN 978-952-62-1198-5 (PDF)ISSN 0355-3221 (Print)ISSN 1796-2234 (Online)

U N I V E R S I TAT I S O U L U E N S I S

MEDICA

ACTAD

D 1359

ACTA

Iikka Lantto

OULU 2016

D 1359

Iikka Lantto

ACUTE ACHILLES TENDON RUPTUREEPIDEMIOLOGY AND TREATMENT

UNIVERSITY OF OULU GRADUATE SCHOOL;UNIVERSITY OF OULU,FACULTY OF MEDICINE;MEDICAL RESEARCH CENTER OULU;OULU UNIVERSITY HOSPITAL

oulu 2016 d 1359 university of oulu p.o. box 8000 fi...

Documents