In this episode, Marc and Mo are joined by special guest Bruce Sangeorzan—Professor of Orthopaedics at the University of Washington and world-renowned foot and ankle researcher—in a lively discussion on the past, present, and future of ankle replacement. Approximately 700,000 knee replacements are performed each year, compared with just 10,000-20,000 ankle replacements. How does this factor affect the number of clinicians who skillful and comfortable in performing ankle replacement as compared with shoulder, knee, and hip replacement? What are the challenges in performing an RCT of ankle arthroplasty, and is an RCT even the right study design for this topic? What design elements seem to be most successful, especially given the space limitations in the ankle region? How do factors such as degenerative disease, BMI, activity level, and adjacent osteotomy affect the results of ankle replacement and arthrodesis? OrthoJOE Mailbag: Feedback, comments, and suggestions from our audience are encouraged and can be sent to orthojoe@jbjs.org Links: • Veljkovic AN, Daniels TR, Glazebrook MA, Dryden PJ, Penner MJ, Wing KJ, Younger ASE. Outcomes of Total Ankle Replacement, Arthroscopic Ankle Arthrodesis, and Open Ankle Arthrodesis for Isolated Non-Deformed End-Stage Ankle Arthritis. J Bone Joint Surg Am. 2019 Sep 4;101(17):1523-1529. doi: 10.2106/JBJS.18.01012. PMID: 31483394. https://jbjs.org/reader.php?id=205473&rsuite_id=2159103&native=1&source=The_Journal_of_Bone_and_Joint_Surgery/101/17/1523/fulltext&topics=fa#info • Muller P, Skene SS, Chowdhury K, Cro S, Goldberg AJ, Doré CJ; TARVA Study Group. A randomised, multi-centre trial of total ankle replacement versus ankle arthrodesis in the treatment of patients with end stage ankle osteoarthritis (TARVA): statistical analysis plan. Trials. 2020 Feb 18;21(1):197. doi: 10.1186/s13063-019-3973-4. PMID: 32070409; PMCID: PMC7029552. https://pubmed.ncbi.nlm.nih.gov/32070409/