Abstract
Background
The recommended indications for total ankle replacement (TAR) are limited, leaving fusion as the only definitive alternative. As longer-term clinical results become more promising, should we be broadening our indications for TAR?
Materials and Methods
Our single-centre series has 133 Mobility TARs with 3–48 months' follow-up. 16 patients were excluded who were part of a separate RCT. The series was divided into two groups. ‘Ideal’ patients had all of the following criteria: age >60y, BMI <30, varus/valgus talar tilt <10°, not diabetic, not Charcot, not post-traumatic. The ‘Not ideal’ group contained those who did not fit any single criteria. We compared complications and outcome scores between both groups.
Results
The ‘Ideal’ group contained 44 ankles vs. 80 in the ‘Not ideal’ group (124 ankles in 117 patients). Complications were (‘Ideal’ vs. ‘Not ideal’): infection: 1 (deep) vs. 3; DVT/PE: 0; periprostheticfracture: 4 vs. 7; CRPS: 2 vs. 2; revision: 0 vs. 2. AOFAS scores showed variable significance (mean values). Pre-op: 27.9 vs. 25.7 (p = 0.459); 3months: 79.4 vs. 73.2 (p = 0.041); 6 months: 79.9 vs. 75.4 (p = 0.053); 12 months: 79.7 vs. 75.8(p = 0.228), 36 months: 77.3 vs. 79.0 (p = 0.655). Further subgroup analysis has been performed.
Discussion
Our results show that indications for TAR can be widened without further morbidity. Each case must be treated individually and accounted for other factors. Varus/valgus tilt can be corrected with appropriate calcaneal osteotomy +/- tendon transfers as a staged or combined procedure. TAR may be considered in younger patients based on functional and occupational demands. We may no longer be able to deter patients on BMI alone. Diabetic patients do not appear to have a higher complication rate.
Conclusion
We have increasing evidence that we should now be considering TAR as the primary treatment for disabling ankle arthritis rather than fusion.