Arthrodesis of the ankle joint is a well-established treatment for painful, end-stage ankle arthritis. Managing deformity, poor bone quality or bone loss poses greater challenges for the surgeon. As a result, angle-stable devices such as blade plates and nonanatomic locking plates have been studied biomechanically and found to exhibit some mechanical advantages over screws in stabilizing the arthrodesis, thus potentially offering a solution. A new anatomically contoured, fixed angled lateral locking ankle arthrodesis plate was developed and its efficacy was assessed for rate of union in patients with deformity, poor bone quality, and with bone loss. The operative technique for using this plate is presented. Eighty-two consecutive cases were treated using this plate in our institution. The plate was used to treat 3 groups of patients with ankle pain: 70 patients with degenerative ankle arthropathy, 6 cases of nonunion following previous attempts at ankle arthrodesis and 6 cases following failed total ankle replacement. There were 70 primary fusions in the study with 40 cases of <10 degrees deformity and 30 cases of >10 degrees deformity in the coronal plane. A higher rate of fusion (97%) was achieved in the cases with <10 degrees deformity compared with 92% in >10 degrees deformity but there was no significant difference (P=0.35) between these groups [time to union in weeks: <10 degrees deformity mean 18 degrees (range, 6 to 42 vs. <10 degrees), deformity mean 21 degrees (range, 11 to 77 degrees). In those cases of nonunion treated with the plate, union was achieved in 5 of the 6 (83%) procedures with a mean time to union of 25 weeks (range, 12 to 44 wk). In those cases of arthrodesis for salvaging failed total ankle replacement, all cases achieved union of their arthrodesis with a mean time to fusion of 20 weeks (range, 11 to 43 wk). This lateral locking plate system is a suitable fixation device in achieving ankle arthrodesis in the presence of deformity, poor bone quality or bone loss. The study supports the concept of locking plate internal fixation for ankle arthrodesis.
Level of Evidence: Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.
Department of Orthopaedic Surgery, Sheffield Teaching Hospitals NHS Foundation Trust, Sheffield, UK
M.B.D. and C.M.B. designed the Ankle Fix plate and therefore receive financial benefits from Zimmer Biomet as a direct result. However, Zimmer Biomet offered no financial assistance in any way towards the conduct of this study or the preparation of the manuscript.
Address correspondence and reprint requests to Mark B. Davies, BM FRCS (Tr & Orth), Department of Orthopaedic Surgery, Sheffield Teaching Hospitals NHS Foundation Trust, Herries Road, Sheffield S5 7 AU, UK. E-mail: email@example.com.