COFAS Multicenter Study Comparing Ankle Replacement and Ankle Fusion: The effect of Ipsilateral peri-articular deformity and arthritis on Mid-term outcome Murray J. Penner, MD, FRCSC Kevin J. Wing, MD, FRCSC Alastair S.E. Younger, MD, FRCS Mark A. Glazebrook, MD, FRCSC Peter J. Dryden, MD, FRCSC Hubert Wong, PhD Timothy R. Daniels, MD, FRCSC
Disclosures The authors disclosures are in the Final AOFAS Mobile App. The authors may have a potential conflict with this presentation due to: Research financial support from: Integra, Biomimetics, Cartiva, J&J DePuy, Acumed Consultancy Integra, Wright, Arthrex, Acumed Royalty Wright
Introduction Ankle fusion (AF) and Replacement (TAR) are accepted treatments for end stage ankle arthritis (ESAA) While AF is reliable, TAR is often preferred by patients Recently, COFAS presented the largest mid- to long-term prospective comparison of AF and TAR Outcomes were comparable at 5.5 yrs mf/u But not stratified for any patient factors
Introduction Potentially important factors include ipsilateral: Intra-articular deformity Significant foot deformity Hindfoot arthritis (or prior fusion) When present, increasingly complex reconstruction techniques are required But the effect of increasingly complex arthritis and reconstruction, as stratified by the COFAS Classification*, on outcome is unknown * Krause et al, FA Specialist, 5:31, 2012
Purpose & Hypotheses Determine if: 1. Outcomes for TAR & AF differ between COFAS ankle types 2. Outcomes differ between TAR & AF for ankles of the same COFAS type
Methods Prospective non-randomized multicenter data (5 sites, 7 surgeons) from the COFAS database Study received ethics approval at all sites Inclusion criteria: Informed study consent Skeletal maturity 1 TAR (mobile bearing) or AF Completed pre-op data set Completed post-op data set, minimum 2 year FU Exclusion criteria: Hx of active or prior infection Charcot arthropathy Significant talar osteonecrosis
Methods Primary Outcome: Ankle Osteoarthritis Scale (AOS) Total of Pain & Disability Sections Secondary Outcome: COFAS Complication Rate
Methods Stratify by COFAS Post-op Classification Non-Complex Types Complex Types COFAS Type 1 2 3 4 PRE-OP Classification Isolated ESAA ESAA with: Ankle varus/valgus >10, instability, or equinus POST-OP Classification Adjunct Procedures Isolated AF or TAR AF or TAR with: ST procedure requiring 2nd incision Ligament recon or release, TAL, GSR, ESAA with: ESAA with: Tibial or HF or MF ST, TN or CC arthritis deformity AF or TAR with: Osteotomy or MF fusion Fib, calc, or tibial osteotomy; MF fusion AF or TAR with: HF fusion ST, TN, CC or Triple fusion
Results 60 50 40 Non-Complex Ankles Pre=56.6 535 Cases 4.0 Yr FU Complex Ankles Pre=50.7 Pre=49.3 Pre=49.5 AOS Total 30 20 Post=26.3 Post=23.4 Post=30.1 Post=23.8 10 N=135 N=252 N=47 N=101 0 Fusion 1&2 TAR 1&2 Fusion 3&4 TAR 3&4 Post-op improved significantly vs. Pre-op in all Types Trend for TAR 1&2 slightly better Post-op than AF 1&2 (p=0.22) Trend for TAR 3&4 slightly better Post-op than AF 3&4 (p=0.10) Trend for TAR 1-4 slightly better Post-op than AF 1-4 (p=0.10)
Results TAR pts: Fusion 1&2 TAR 1&2 Fusion 3&4 TAR 3&4 << << > > < < << << >> << < Age (yrs) 55.8 66.2 51.9 63.0 Diabetes % 10.9 6.6 11.1 4.7 Inflam Arthritis % 8.8 15.4 13.0 27.1 Revision % 1.5 8.1 0 4.7 Amputation % 0 0.4 3.7 0.9 Tot complic cases % 1.5 10.3 5.6 11.2 were a decade older (p<0.05) Had diabetes less frequently Had inflammatory arthritis much more commonly Complications requiring reoperation were more common in TAR and Types 3&4 Aseptic revision more common in TAR BUT, Amputation more common in Fusion, particularly Types 3&4 (non-septic)
Conclusion At mean 4 yr FU, both TAR and AF result in significant outcome improvement for all types of arthritis Complex (Types 3&4) Fusions have somewhat worse outcomes than Non-Complex (Types 1&2) Fusions (NS), while this difference is not present with TARs TAR outcomes slightly better (NS) than AF in both Complex and Non-Complex arthritis despite: Pt age greater by a decade a much higher incidence of inflammatory arthritis TAR has a higher complication rate, but notably lower amputation rate in Types 3&4
References Daniels, T. R., Younger, A. S. E., Penner, M. J., Wing, K., Dryden, P. J., Wong, H., & Glazebrook, M. (2014). Intermediate-Term Results of Total Ankle Replacement and Ankle Arthrodesis: A COFAS Multicenter Study. The Journal of Bone and Joint Surgery, 96(2), 135 142. doi:10.2106/jbjs.l.01597 Haddad, S. L., & Coetzee, J. C. (2007). Intermediate and long-term outcomes of total ankle arthroplasty and ankle arthrodesis. A systematic review of the literature. The Journal of Bone and Joint Surgery American Volume, 89(9), 1899 1905. doi:10.2106/jbjs.f.01149 Penner, M. J., Krause, F. G., Di Silvestro, M., Wing, K. J., Glazebrook, M. A., Daniels, T. R., et al. (2010). Inter- and intraobserver reliability of the COFAS end-stage ankle arthritis classification system. Foot & Ankle International / American Orthopaedic Foot and Ankle Society [and] Swiss Foot and Ankle Society, 31(2), 103 108. doi:10.3113/fai.2010.0103 Krause, F. G., Penner, M. J., Di Silvestro, M., Wing, K. J., Glazebrook, M. A., Daniels, T. R., et al. (2012). The Postoperative COFAS End-Stage Ankle Arthritis Classification System: Interobserver and Intraobserver Reliability. Foot & Ankle Specialist, 5(1), 31 36. doi:10.1177/1938640011433051