Keywords: Trabecular Metal Total Ankle, Revision Ankle Arthroplasty, Transfibular Approach
Introduction/Purpose: Revision total ankle arthroplasty (TAA) is a technically challenging procedure with increasing demand. Modes of primary TAA failure requiring revision most commonly include aseptic loosening, instability, component migration and less commonly, periprosthetic infection. The management of inadequate bone stock after explantation of primary components as well soft tissue compromise from repeat surgical exposure pose great difficulties during revision procedures. Conversion to arthrodesis and/or amputation, traditionally have been and still are options within the treatment algorithm of TAA failure. We believe the management of this problem with transfibular TAA has great potential and has been understudied. This study presents minimum 2 year clinical and radiographic outcomes following revision of failed TAA with transfibular, trabecular metal (TM) TAA.
Methods: A total of 11 ankles (11 patients, average 72.1 years-old, 45% females) were retrospectively identified from October 2012 to June 2023. All patients had presented to the treating surgeon with failed primary or revision TAA (STAR, n=6, Agility, n=2, Salto Talaris, n=2, Infinity, n=1) performed at outside institutions, and were indicated for revision arthroplasty using a transfibular TM prosthesis. Failure included aseptic loosening/subsidence (n=7) and periprosthetic joint infection (PJI, n=4). Patient demographics, comorbidities, and surgical history were recorded. Any complications or reoperations following revision TAA were noted. Pre- and postoperative patient-reported outcomes were assessed using Short Form Health Survey (SF-12) physical (PCS) and mental (MCS) component scores, Ankle Osteoarthritis Scale (AOS), and Visual Analog Scale (VAS). Tibiotalar range of motion (ROM) was assessed on postoperative flexion-extension films, and alignment and incidence of implant subsidence were assessed on standing films.
Results: Average time to revision TM TAA was 9.9 years (range, 2-20), average follow-up from revision TM TAA was 2.9 years (range, 2.1-3.5). All 4 cases with PJI were successfully treated with two-stage revision (explantation with antibiotic spacer followed by TM TAA). There was significant improvement in VAS and AOS Pain (p<0.05). Mean coronal (90.7°) and sagittal (86.1°) alignment was within normal limits. Tibiotalar ROM was 11.4° (range, 4.6-18.9°) dorsiflexion, 12.6° (range, 4.6-24.3°) plantarflexion. There was 1 (9%) revision and 4 (36%) reoperations: 1 revision at 1.5 months for tibial component migration, 1 I&D with polyethylene exchange and implant retention at 4.5 months for deep infection, 1 exostectomy at 6.5 months for tibial exostosis, 2 gutter debridements for impingement.
Conclusion: In patients with failed TAA who wish to avoid fusion or amputation, revision arthroplasty using a transfibular approach can provide a viable treatment option and should be considered. However, it remains a challenging procedure and patients should be counseled regarding the increased risk for reoperations. Longer- term follow-up is needed to determine the durability of revision arthroplasty to TM TAA.
