Department of Orthopaedic Surgery

Complications of the Tornier Salto Talaris Total Ankle Prosthesis: A Single-Surgeon Experience

Garett Pangrazzi, MD; Erin Baker, MS; Philip Shaheen, BS; Paul Fortin, MD

IFFAS/AOFAS

September 19-23, 2014

Chicago, IL

Department of Orthopaedic Surgery

Complications of the Tornier Salto Talaris Total Ankle Prosthesis: A Single-Surgeon Experience

Garett Pangrazzi, MD My Disclosure is in the final AOFAS Mobile App.

I have no potential conflicts with this presentation.

Paul Fortin, MD My Disclosure is in the final AOFAS Mobile App.

I have a potential conflict with this presentation due to: Paid consultant for Tornier.

Department of Orthopaedic Surgery

Study Objective

• To evaluate postoperative complications encountered with the Salto Talaris total ankle arthroplasty (TAA) system (Tornier US, Bloomington, Minnesota).

Department of Orthopaedic Surgery

Methods

• Review medical records for primary Salto Talaris TAA cases from 2008 - 2013

• Fusion take-downs excluded

• Radiographic Measurements and zones of lucency examined

Pre and postoperative measurements, including tibial angle (TA), tibiotalar angle (TAL), posterior tibial slope (TS), Talocalcaneal angle (TCA)

AP (A) and lateral (B) radiographic zones of lucency as described by Bonnin et al.1 has been modified to include zone 11 (lateral malleolus)

Department of Orthopaedic Surgery

Results: Medical Records Review

Total # Patients

96

Total # Ankles

104 (8 Bilateral)

Sex 48 Male, 48 Female

Average Age 65 (35 – 86)

Body Mass Index (BMI)

29 (17 – 50.3)

Etiology OA = 58; RA = 23;

Posttraumatic = 22; Unknown = 1

Table 1: Patient Demographics

Procedure Frequency

Tendo-Achilles Lengthening (T-AL Only) 77(26)

Prophylactic Medial Malleolus Fixation 34

Hardware Removal 13

Prophylactic ORIF Fibula 12

Lateral Ankle Ligament Reconstruction 11

Subtalar Fusion 11

Calcaneal Osteotomy 9

Talonavicular Fusion 8

Syndesmotic Fusion 5

Midfoot Fusion 3

Hindfoot Fusion 2

1st Metatarsal Osteotomy 2

Other (# of patients) 1 (9)

Table 2: Concurrent Procedures at Primary TAA

Department of Orthopaedic Surgery

Results: Revision & Reoperation Rates

• 29-month average followup (range, 4 – 64)

• 28 complications in 25 ankles

• Reoperation Rates

– 11% overall (11/104)

– 44% (11/25)

• Revision Rate

– 0.96% (1/104)

• 41-month average followup (range, 24 – 69)

• 18 Complications in 16 ankles

• Reoperation Rates

– 10.5% (8/76)

– 50% (8/16)

• Revision Rate

– 1.3% (1/76)

OVERALL (n=104)

2-YEAR FOLLOWUP (n=76)

Diagnostic Complication

Procedure At Reoperation Frequency

Infection Irrigation and Debridement 2

Nonunion (of Fusion) Revision/Hardware Removal 2/1

Pain Revision to InBone TAA (Wright Medical, Arlington, TN)

1

Pain and subsidence Compression Screw 1

Postoperative Bone Fracture

Medial Malleolus ORIF 1

Medial Impingement Ankle Arthroscopy and Exostectomy/Exostectomy Alone

1/1

Wound Healing Debridement and Closure 1

Table 3: Diagnoses/Complication and Procedures at Reoperation and/or Revision TAA

Department of Orthopaedic Surgery

Results: Complication Rate & Types Rate of complication in the study population, according to type, reported via the Glazebrook classification system.2 System has been modified to include uncharacterized pain, nerve palsy and medial impingement (*). The two reports of nerve palsies were associated with popliteal nerve catheter use.

* * *

Rate of reoperation, according to complication type, reported via the Glazebrook classification system.2

Department of Orthopaedic Surgery

Results: ‘Learning Curve’ & Onset of Complications

Rate of complication normalized to number of TAA performed per year.

Time to onset of all complications, based on diagnosis at follow-up visits. The onset of

one subsidence case was unknown.

Department of Orthopaedic Surgery

Results: Identification of “At Risk” Population

• Definition— Radiographic evidence of:

Subsidence

Periprosthetic cystic changes

Periprosthetic Lucency

• 39 patients (38%)

Clinical Example of “at risk” patients. AP (A) and lateral (B) view radiographs of Salto Talaris TAA. This TAA was revised to the In-Bone TAA (C, D). AP (E) and lateral (F) view radiographs of a TAA,

currently defined as “at risk” in our series, exhibiting similar periprosthetic lucency.

Revised “At Risk”

Department of Orthopaedic Surgery

Results: Lucency vs. “Keel Osteopenia”

Zones of lucency for tibial (A) and talar (B) components, based on AP and lateral views.

Zone 11 represents lateral malleolus (lat mal). TAA with radiographic lucency were considered

“at risk”.

AP radiographs demonstrating “keel osteopenia” in two study patients (A, B).

There were 35 patients in this group. They were not considered as being “at risk”.

Department of Orthopaedic Surgery

Radiographic Analysis

Reoperation No reoperation P-Value

TTR 0.29 0.34 0.013

ATA 1.3 2.8 0.019

“At Risk” Not “At Risk” P-Value

TAL 94.4 89.6 0.043

Change in TAL 6.4 0.8 0.015

Keel Osteopenia

No Keel Osteopenia

P-Value

TA 88.9 89.9 0.022

TAL 87.4 89.0 0.003

ATAL 2.9 1.7 0.006

Valgus “At Risk” ǂ

Valgus Not “At Risk” ǂ

P-value

ATAL 12.8 6.7 0.016

Change ATAL 14.1 6.7 0.017

Statistically significant subset analyses. ǂ In valgus preoperatively, and categorized as “at risk” or not “at risk” postoperatively.

Measurement Preoperative Postoperative Change

Tibial Angle (TA) 88.4 (4.6; 75.6 – 99.9)* 89.6 (1.9; 83.5 – 93.8)* 1.2 (4.9; -12.8 – 14.3)

Tibial Angle, Absolute Value (ATA) 3.9 (2.9; 0.1 – 14.4)** 1.4 (1.3; 0.0 – 6.5)** 3.9 (3.1; 0.0 – 14.3)

Tibiotalar Angle (TAL) 91.5 (10.6; 62.1 – 126.5)* 88.5 (2.4; 81.6 – 93.1)* -2.9 (10.5; -42.8 – 28.2)

Tibiotalar Angle, Absolute Value (ATAL) 7.8 (7.3; 0.09 – 36.5)** 2.1 (1.9; 0.0 – 8.4)** 7.8 (7.6; 0.1 – 42.8)

Posterior Tibial Slope (TS) 81.2 (6.1; 61.3 – 99.4)** 85.3 (2.8; 77.0 – 93.8)** 4.0 (6.6; -16.75 – 21.1)

Tibiotalar Ratio (TTR) 0.33 (0.09; 0.09 – 0.54) 0.30 (0.05; 0.20 – 0.49) 0.004 (0.07; -0.19 – 0.19)

Talocalcaneal Angle (TCA) N/A 9.9 (5.6; -12.7 – 21.8) N/A

Table 4: Pre and Postoperative Radiographic Measurements of TAA. *P < 0.05; **P < 0.001

Department of Orthopaedic Surgery

Conclusions & References • Complication rate

– 24%

• Reoperation and revision rate similar to previously reported data3,4 – 11% and 0.96% overall, respectively

• No difference in pre and postoperative radiographic measures… – in ankles that had complications compared to those without complications – in ankles that had at least one concurrent procedure vs. TAA alone

• “At Risk” implants were identified – “At Risk” implants in significantly more valgus preoperatively

• “Keel Osteopenia” – Possibly results from stress shielding phenomenon – Unknown clinical implications, but may change strategy for future revision surgery

References: 1. Bonnin et al. The Salto Total Ankle Arthroplasty. Survivorship and Anyalysis of Failures at 7 to 11 years. CORR.

2011. 469: 225-236. 2. Glazebrook, M. et al. Evidence-Based Classification of Complications in Total Ankle Arthroplasty. Foot Ankle Int.

2009. 30: 945-949 3. Schweitzer et al. Early Prospective Results of the Salto-Talaris Total Ankle Prosthesis. J Bone Joint Surg Am.

95(11): 1002-1011, 2013. 4. Nodzo, SR et al. Short to Midterm Clinical and Radiographic Outcomes of the Salto Total Ankle Prosthesis. Foot

Ankle Int/AOFAS and Swiss Foot and Ankle Society. 2013