Does a fibula-sparing approach improve outcomes in tibiotalocalcaneal arthrodesis?

BACKGROUND: Tibiotalocalcaneal (TTC) arthrodesis is considered a salvage procedure for either complex deformity or arthritis about the hindfoot, and can be performed via fibula-resection (FR) or fibula-sparing (FS) approaches. The primary aim of this study was to investigate differences in outcomes in FR versus FS TTC arthrodeses.

METHODS: This was a retrospective cohort study reviewing outcomes of TTC arthrodesis at a single institution. Patients who underwent a TTC arthrodesis from 2005 to 2017 and had minimum two-year follow-up were included. Preoperative diagnosis, pre- and post-operative radiographic coronal alignment, fixation methods, and complications were compared between groups.

RESULTS: 107 patients (110 ankles) underwent TTC arthrodesis, with a mean age of 57.0 years (sd, 14.0 years). The mean clinical follow-up was 50.7 months (range, 24-146) and mean radiographic follow-up was 45.8 months (range, 6-146 months). Pre-operative diagnoses included arthritis (N = 40), prior non-union (N = 21), Charcot neuro-arthropathy (N = 15), failed total ankle arthroplasty (N = 15) and avascular necrosis of the talus (N = 19). Sixty-nine ankles comprised the FS group and 41 comprised the FR group. There was no significant difference in the non-union rate between groups (29% FR vs 38% FS, p = 0.37), complication rate (59% FR vs 64% FS, p = 0.59), or post-operative coronal standing radiographic alignment (89.6 degrees FR, 90.5 degrees FS, p = 0.26). Logistic regression analyses demonstrated a pre-operative diagnosis of failed TAA was associated with post-operative nonunion (OR:3.41,CI:1.13-11.04,p = 0.03). Pre-operative indication for TTC arthrodesis of arthritis alone was associated with a decreased risk of non-union (OR:0.27,CI:0.11-0.62,p = 0.002).

CONCLUSION: TTC arthrodesis is a successful surgical option for complex hindfoot deformity, arthritis, and limb salvage regardless of surgical approach. We did not detect a difference in the union rate, incidence of complications, or coronal plane radiographic alignment in fibula-sparing versus fibula-resection constructs. Patients with a pre-operative indication for surgery of arthritis may be at decreased risk of developing non-union.

LEVEL OF EVIDENCE: III - Retrospective cohort study.