What variables influence final range of motion following Total Ankle Arthroplasty Kevin T. Grosshans MD Mark S. Myerson MD
Disclosures My disclosure is in the Final AOFAS Mobile App I have no potential conflicts with this presentation
Purpose To retrospectively review previous total ankles and examine what variables may contribute to an acceptable final motion outcome. This information could help in distinguishing which patients are more appropriate candidates for an arthroplasty versus an arthrodesis.
Methods Retrospective analysis of 163 primary total ankles performed between 2009 and 2012 using a single implant (Tournier Salto Talaris) Radiographs examined for the presence of flexion/extension views at 12 month followup. 78 patients had complete radiographs.
Methods All 78 patients had radiographs analyzed to assess tibiotalar ROM at 12 month follow-up. Cobb angle difference measured from tangents to tibial keel and bottom of talar component 6,15
Methods All 78 ranked based on ROM at 12 months. Top and bottom 25 selected for study cohorts Each cohort further analyzed for. Pre-operative tibiotalar motion (measure in a similar fashion) Pre-operative diagnosis Prior or concurrent procedures on the foot or ankle Age and BMI Post-operative protocol, including time to weight bearing, time to start of physical therapy, duration and frequency of therapy Information gathered from radiographs, chart, and by phone interview. Consent obtained at time of phone interview.
Results No difference in age or BMI between the two groups (p=0.52, p=0.14 respectively) No difference in the post-operative protocols Time to weight bearing was 5.52 weeks and 5.42 weeks in the top and bottom groups, respectively (p=0.85) Time to start of PT was 4.96 weeks and 4.77 weeks in the top and bottom groups, respectively (p=0.80) Frequency and duration of PT were the same (p=0.47, p=0.67 respectively)
ROM Results 35 30 25 20 15 10 5 Top 25 Bottom 25 Top 25 increased from 28.9 o to 33.3 o Bottom 25 decreased from 17.9 o to 12.3 o p=0.0 for comparison of post-op ROM between groups 0 Pre-op ROM Post-op ROM
Pre-operative Diagnosis Top 25 group -Large number of primary OA resulting from previous ankle instability, varus or valgus Bottom 25 group -Large number of post-traumatic OA patients Post-traumatic OA (n=4) Primary OA (n=21) Post-traumatic OA (n=12) Primary OA (n=11) RA (n=1)
Conclusion As expected, pre-operative range of motion had a large impact on post-operative motion Post-traumatic arthritis patients were more likely to have poor motion outcomes, where as patients with previous varus or valgus instability had the best motion outcomes. Time to weight bearing and use of PT did not differ in the two cohorts.
References 1. Lagaay PM, Schuberth JM. Analysis of ankle range of motion and functional outcome following total ankle arthroplasty. J Foot Ankle Surg. 2010 Mar-Apr;49(2):147-51. 2. Mann JA, Mann RA, Horton E. STAR ankle: long-term results. Foot Ankle Int. 2011 May;32(5):s473-84. 3. Schuberth JM, McCourt MJ, Christensen JC. Interval changes in postoperative range of motion of Salto-Talaris total ankle replacement. J Foot Ankle Surg. 2011 Sep-Oct;50(5):562-5. 4. Brodsky JW, Polo FE, Coleman SC, Bruck N. Changes in gait following the Scandinavian Total Ankle Replacement. J Bone Joint Surg Am. 2011 Oct 19;93(20):1890-6. 5. Nunley JA, Caputo AM, Easley ME, Cook C. Intermediate to long-term outcomes of the STAR Total Ankle Replacement: the patient perspective. J Bone Joint Surg Am. 2012 Jan 4;94(1):43-8. 6. Ajis A, Henriquez H, Myerson M. Postoperative Range of Motion Trends following Total Ankle Arthroplasty. Foot Ankle Int, May 2013;34(5):645-56. 7. Flavin R, Coleman SC, Tenebaum S, Brodsky J. Comparison of Gait after Total Ankle Arthroplasty and Ankle Arthrodesis. Foot Ankle In. 2013 May 13. 8. Choi JH, Coleman SC, Tenebaum S, Pole FE, Brodsky JW. Prospective Study of the Effect on Gait of a Two-component Total Ankle Replacement. Foot Ankle Int. Jul 2013. 9. Valderrabano V, Pagenstert GI, Muller AM, Paul J, Henninger HB, Barg A. Mobile and Fixed bearing total ankle prosthesis: is there really a difference? Foot Ankle Clin. 2012 Dec;17(4):565-85. 10. Tochigi Y, Rudert MJ, Brown TD, McIff TE, Saltzman CL. The effect of accuracy of implantation on range of movement of the Scandinavian Total Ankle Replacement. J Bone Joint Surg Br. 2005 May;87(5):736-40. 11. Yamaguchi S, Tanaka Y, Banks S, Kosugi S, Sasho T, Takahashi K, Takakura Y. In vivo kinematics and articular surface congruency of total ankle arthroplasty during gait. J Biomech. 2012 Aug 9;45(12):2103-8. 12. Bai LB, Lee KB, Song EK, Yoon TR, Seon JK. Total ankle arthroplasty outcome comparison for post-traumatic and primary osteoarthritis. Foot Ankle Int. 2010 Dec;31(12):1048-56. 13. Hobson SA, Karantana A, Dhar S. Total ankle replacement in patients with significant pre-operative deformity of the hindfoot. J Bone Joint Surg Br. 2009 Apr:91(4):481-6. 14. Kim, BS; Choi, WJ; Kim, YS; Lee, JW. Total ankle replacement in moderate to severe varus deformity of the ankle. J Bone Joint Surg Br. 91:1183 1190, 2009. 15. Coetzee JC, Castro MD. Accurate measurement of ankle range of motion after total ankle arthroplasty. Clin Orthop Relat Res. 2004 Jul;(424):27-31.