Subtalar ArthroereisisHistory and Application

The Non-Weightbearing to Weightbearing Normal Foot

Normal arch

Open sinus tarsi

The Non-Weightbearing to Weightbearing FlatfootFlexible flatfoot

Closing sinus tarsi

Juvenile Talipes Valgus

Nine Year old healthy youth, except for a long history of painful feet. Is not active in any form of

athletics. A little better with custom orthotics

Obliterated sinus tarsi

Adult Talipes Valgus

66 year old female with rheumatoid arthritis and foot pain for years. Stage 2 PTTD. On Enbrel and prednisone.

Obliterated sinus tarsi

Surgical correction of flatfootARTHRODESIS

(Eliminates joint motion)

ARTHROEREISIS(Restricts excessive

joint motion)

SOFT-TISSUEPROCEDURES

OSTEOTOMIES(Preserves joint motion)

Subtalar Arthroereisis• From the Greek root ereidein (to press a

thing against)• the term ereisis means ‘a propping up’ and

the term arthroereisis itself means “an operation to limit motion of a joint in cases of excessive mobility from unknown weakness”

Churchill’s Illustrated Medical Dictionary. New York, Williams and Wilkins, 1989

Milestones in the Development of Subtalar Arthroereisis

1974Subotnick

1946Chambers

1970LeLievre

1962Haraldsson

1952Grice

Posterior Facet Osteotomy Chambers, 1946

Chambers, EF: An operation for the correction for flexible flat feet in adolescents. West J. SGO. 54:77-86, 1946. From the Jefferson

Medical College, Philadelphia.

Extra-Articular Subtalar Arthrodesis Grice, 1952

Grice, DS: An extra-articular arthrodesis of the subastragalar joint for correction of paralytic flat feet in children. JBJS. 34A:927-940, 1952. From the Massachusetts Infantile Paralysis Clinics, Children’s Hospital, Boston.

Bone Wedge “Arthrorhisis” Haraldsson, 1962

Haraldsson, S: Operative treatment of pes planovalgus staticus juvenilis. Act Orthop. Scand. 32: 492-498, 1962. From the Orthopaedic Clinic, Lund,

Sweden.

Staple arthroereisis LeLievre, 1970

LeLievre, J: Current concepts and correction of the valgus foot. CORR. 70:43-55, 1970. From Paris, France.

Custom-carved plug Subotnick, 1974

Subotnick, S: The subtalar joint lateral extra-articular arthroereisis. JAPA. 67:157-171, 1977. From the California

College of Podiatric Medicine, San Francisco.

Evolution of subtalar arthroereisis

4 Pathways

Posterior facet osteotomy Chambers, 1946

Bone wedge “arthrorhisis”Haraldsson, 1962

Staple arthroereisisLeLievre, 1970Open sinus tarsi model

3

Only 1 axis-altering device

• One piece• Ultra high molecular weight polyethylene

(HMPE)• Platform & stem• In sinus tarsi• Stem in calcaneus to fixate the implant• Posterior facet arthroplasty to seat the implant• Different sizes

STA-pegSmith, 1976

Implants: Posterior Facet Osteotomy Pathway

Axis-altering deviceSmith, 1976

Posterior facet osteotomyChambers, 1946

Elevating the subtalar joint axis reduces hindfoot eversion.

Implants: Open Sinus Tarsi Pathway

Implant-blocking device(Vogler, 1987)Open sinus tarsi

Blocking the anterior translation of the lateral talar processreduces hindfoot eversion.

Implant-Blocking Devices• HMPE• Platform & stem• In sinus tarsi• Stem in calcaneus to fixate

the implant• Different sizes

• Silastic• Cap & stem• In sinus tarsi• Stem in calcaneus to fixate

the implant• Different sizes

STA-peg Smith, 1976

Sgarlato “mushroom”Sgarlato, 1983

Implants: Bone Wedge “Arthrorhisis” Pathway

Self-locking wedge(Vogler, 1987)

Bone wedge “arthrorhisis”Haraldsson, 1962

Prevents contact between the lateral talar process with the floor of the sinus tarsi reducing hindfoot eversion.

Self-Locking Wedge: The 70’S

• HMPE• Threaded cylinder• In sinus tarsi• Different sizes

• Silastic• Carved block• In sinus tarsi• Adjustable

Custom-carved plug Subotnick 1974

Valenti “threaded” implantValenti 1976

Viladot “cuplike” implantViladot 1977

• Silastic• Umbrella & stem• In sinus canalis & sinus tarsi • Different sizes

Self-Locking Wedge: The Expandables

• PE & titanium• Expanding cylinder &

internal screw• In sinus tarsi

• Teflon & stainless steel• Expanding cylinder &

internal screw• In sinus tarsi

Flatfoot expanding implantGiannini 1985

KalixViladot 2003

Flatfoot expanding implantGiannini 2001

• PLLA (absorbable)• Expanding cylinder

& internal screw• In sinus tarsi

• Titanium• Threaded

cylinder/cone/cylinder & cannulated

• In sinus canalis & sinus tarsi

• Cut interosseous ligament• Different sizes

• Titanium• Threaded cylinder,

slotted and cannulated• In sinus tarsi• Different sizes MBA

Maxwell/Brancheau 1997

HyProCureGraham 2004

“Grandfather”Valenti implant

Self-Locking Wedge

The MBA clonesCompany DESIGN MATERIAL FEATURE(S)

CSI(Futura)

Threaded cone Titanium Anatomic design, dimples

Talar-fit(Osteomed)

Threaded cone Titanium alloy

Anatomic design

bioBlock(KMI/Integra)

Threaded cylinder PLLA Absorbable

ProStop(Arthrex)

Threaded cone Titanium Anatomic design

TOV(Vilex)

Threaded cone Titanium alloy

Anatomic design

Classifying Implants

First-generation implants • 1970’s and 1980’s• At least eleven designs• Evolved from…

– Haraldsson procedure– Chambers procedure– Open sinus tarsi model

Second-generation implants

• After 1997 (MBA)• At least 12 designs• More advanced designs

Fit

Fixation

Environmentmodification

Location

Shape

Material

Vogler’sbiomechanicalclassification

Numberof components

Classificationof implants

Biomechanical classification (Vogler,1987)

• Self-locking wedge (SLW)• Axis-altering device (AAP)• Impact-blocking device (IBD)

Adapted from: Maxwell, JR; Cerniglia, MW: Subtalar joint arthroereisis. In AS Banks; MS Downey; DE Martin; SJ Miller, ed., McGlamry’s ComprehensiveTextbook of Foot and Ankle Surgery, 3rd edition, Philadelphis, Lippincott Williams & Wilkins, 2001, p. 904. Reprinted with permission.

SLW AAP IBD

MaterialNonabsorbable• Silastic

• Polyethylene (PE)

• Titanium

• Hybrid (metal & PE)

Absorbable• Poly-L-lactic acid (PLLA)

Classification of implantsLocation• Sinus tarsi

Sinus tarsi Sinus canalis

• Sinus canalis

Definitions

• The sinus tarsi is NOT a joint• No articular surfaces present• Only soft tissue

Anatomy of the Sinus Tarsi

• Shape of the sinus versus canalis tarsi

• Axis is Distal plantarlateral to Proximal dorsomedial

Aims of Arthroerisis

• Restrict excessive range of motion at the subtalar joint

• Allow 3-5º of range of motion • Preserve functionality of the subtalar

joint

Lundeen RO: The Smith STA-peg operation for hypermobile pes planovalgus in

children. J Am Podiatr Med Assoc. 75(4):177-83, 1985

Indications

• >3 years of age • Flexible foot type• Pathologic foot without

active symptomotology?

Food and Drug Administration: Indications for use for K042030, device

name: HyProCure®

subtalar implant system. Rockville, MD. Sep 16th, 2004

Contraindications• Rigid foot type• Femoral

anteversion/antetorsion• Tibial torsion• Destructive

osteoarthritis changes causing symptoms

Hutchinson, J: Contributions to Orthopaedic Surgery, New York, Rand, Avery and Co, 1880. P. 93

Patient Examination

• Weightbearing and non-weightbearing films of foot to compare position

• 3 radiographic signs:– Calcaneal valgus– Obliteration of the sinus tarsi– Important in the cavus foot

Needleman RL: A operative approach for flexible flatfeet in adults including a subtalar arthroereisis with the MBA sinus tarsi implant. Foot

Ankle Int. 27(1):9-18, 2006

Chadha, H; Pomeroy, G; Manoli, A: Technique tip: radiologic signs of unilateral pes planus. Foot Ankle Int. 18:603-604, 1997

Patient Examination• Fluoroscopy far

superior for this examination

• Real-time view of motion at the sinus tarsi

Results

• Adults with ‘acquired’ deformities– Adjunctive procedures done: double calcaneal

osteotomies, Cotton, tendo-Achilles lengthening or Gastrocnemius recession

– Arthroereisis done to limit subtalar joint range of motion

– Average of 8-12+ weeks to weight bearing with associated morbidity

Schon LC: Subtalar Arthroereisis: A New Exploration of an Old Concept. Foot Ankle Clin N Am. 12 329-339, 2007

Soomekh DJ, Baravarian B: Pediatric and Adult Flatfoot Reconstruction: Subtalar Arthroereisis versus Realignment

Osteotomy Operative Options. Clin Podiatr Med Surg. 23 695-708, 2006

Results• Adults with flatfoot alone

– Cylindrical and Conical devices solely have high removal rates

– Wine glass shape (HyProCure®) used as sole modality has low removal rate (<3%)*

• No tendo-Achilles lengthening or Gastroc recession done

Soomekh DJ, Baravarian B: Pediatric and Adult Flatfoot Reconstruction: Subtalar Arthroereisis versus Realignment

Osteotomy Operative Options. Clin Podiatr Med Surg. 23 695- 708, 2006

* Unpublished data based upon a study of 284 patients over a two year follow-up time

Removal Rates

• Pediatrics– 0% [Giannini]1

– 5% [Nelson et al]2

– 33% [Sangeozan]3

– 60% [Manoli]41Giannini S, Kenneth A. Johnson Memorial Lecture: Operative treatment of the flatfoot: why and how. Foot Ankle Int. 19(1):52-8, 19982Nelson SC, Haycock DM, Little ER. Flexible Flatfoot Treatment with Arthroerisis: Radiographic Improvement and Child Health Survey Analysis. P. 1493Sangeorzan BJ, Mosca V, Hansen ST Jr: Effect of calcaneal lengthening on relationships among the hindfoot, midfoot, and forefoot. Foot Ankle. 14(3):136-41, 19934Needleman RL: A operative approach for flexible flatfeet in adults including a subtalar arthroereisis with the MBA sinus tarsi implant. Foot Ankle Int. 27(1):9-18, 2006

Removal Rates

• Adults– Needleman

• 39% (28 feet with 11 removals)

– Schon• 30-40% (depending upon implant, having used

MBA (KMI), Futura (Nexa), ProStop (Arthrex)

Retention of Correction

• Reported by Schon as high• Theory that once soft tissue healed, the implant was

no longer needed• Possibly due to adjunctive procedures and not

residual to the arthroereisis procedure itself?

Schon LC: Subtalar Arthroereisis: A New Exploration of an Old Concept. Foot Ankle Clin N Am. 12 329-339, 2007

Complications• Cyst formation1

• Silastic breakdown synovitis2

• Overcorrection/undercorrection• Device migration (backing out)

– Dependent upon ingrowth of soft tissue

• Lateral foot and ankle soft tissue strain– New, rectus position of the foot/ankle

1Rockett AK, Mangum G, Mendicino SS: Bilateral intraosseous cystic formation in the talus: a complication of subtalar arthroereisis.

J. Foot Ankle Surg. 37:421-425, 19962Sammarco G, Tabatowski K: Silicone Lymphadenopathy

Associated with Failed Prosthesis of the Hallux: A Case Report and Literature Review

2Worsing RA, Engber WD, Lange TA: Reactive synovitis from particulate silastic. J Bone Joint Surg Am. 64: 581-585, 1982

Complications

• Infection• Psychogenic reactions• Wearing of the material in non-metallic

implants• Unremitting and unresolving pain

Conclusions

• Acts as an “internal orthotic”1

• Reversible procedure• Can be step one in a multi-step surgical approach,

with adjunctive procedures done later on• Can be combined with adjunctive osteotomies,

plications, lengthenings

1Zaret, DI; Myerson, MS: Arthroereisis of the subtalar joint. Foot Ankle Clinics N. Am. 8:605-617, 2003

Conclusions• Using the correct device in the correct

patient• Proven in Pediatric cases• Proven in Adult cases

– Especially as part of posterior tibialis tear or dysfunction

Thank You