Learning curve of total ankle arthroplasty: a systematic review

Together with ankle arthrodesis, total ankle arthroplasty is now accepted as a first-line intervention in the management of end-stage arthritis of the ankle. The evidence regarding how outcomes are affected by surgeon experience is inconsistent; we performed a systematic review to evaluate the effect of a learning curve in total ankle arthroplasty outcomes.

An electronic database search was performed in PubMed, Embase, ISI Web of Science and Cochrane trials. Two reviewers independently conducted a two-stage title/abstract and full text screening. English-language original research studies comparing patient-reported outcome measures (PROMs), complication/revision rates, operative time, length of stay or radiation exposure according to surgeon experience were included. Quality assessment was performed using the methodological index for non-randomised studies.

All but one included study report either improved PROMs, reduced complication/revision rate, reduced hospital stay length/operative time or reduced radiation exposure with increasing surgeon experience. However, the majority of these findings lack statistical significance. Two studies assessing the plateau of the learning curve report a wide range of plateau thresholds between 9 and 39 cases.

This review finds a largely non-significant trend towards improvements in PROMs, complication, and revision rates with improved surgeon experience. The lack of statistical significance in a number of studies may be partially explained by methodological flaws, with more suitably designed studies reporting significant improvements. Future research into the effect of advancements in implant design and insertion guides is required to further characterise the magnitude of the learning curve and guide both mitigation and learning strategies.