When a total ankle replacement fails, arthrodesis has been advocated as the treatment of choice. With the availability of a wide spectrum of implants, revision arthroplasty may become a viable alternative.
We reviewed a consecutive series of 117 cases (116 patients [fifty-six female and sixty male]; mean age, 55.0 ± 12.0 years) in which a total ankle arthroplasty failed after a mean of 4.3 years and was revised with use of the HINTEGRA three-component total ankle prosthesis. The reason for revision involved the metallic components in sixty ankles (51%), the bone in twenty-eight (24%), the soft tissues in twenty (17%), and infection in nine (8%). The talar component was revised in 104 ankles (89%) and the tibial component, in 106 (91%).
Early complications included a fracture of the malleoli in two ankles and a dislocation of the polyethylene insert in one. Seventeen (15%) of the revision arthroplasties required further revision surgery, in most cases for loosening of one or two of the prosthetic components. The mean American Orthopaedic Foot & Ankle Society (AOFAS) hindfoot score for the remaining 100 ankles (85%) improved from 44 ± 18 preoperatively to 72 ± 19 (p < 0.01) at the time of the latest follow-up (mean, 6.2 years). The estimated survival of the revision arthroplasties at nine years, with loosening of components as the end point, was 83%. The prevalence of component loosening was higher (p < 0.005) with the use of single-coated hydroxyapatite components (six of twenty-three ankles, 26%) than with double-coated components (five of ninety-four ankles, 5%). The correlation between the extent of bone loss at the resection surface and the prevalence of component failure was weak and not significant.
The medium-term results of revision arthroplasty after a failed total ankle arthroplasty were similar to those after primary arthroplasty. The key to success was firm anchorage of the components to primary bone stock. A single hydroxyapatite component coating should no longer be used for revision total ankle arthroplasty.