Total Ankle Arthroplasty Survivorship: A Meta-analysis

Abstract

The gold standard for management of end-stage ankle arthritis was previously ankle arthrodesis; however, improvements in total ankle replacements are making this a more viable treatment option. The primary aim of this meta-analysis was to evaluate the survivorship of total ankle replacement implants currently in use. An extensive search strategy initially captured 20,842 citations that were evaluated for relevance. Abstract screening produced 97 articles to be read in entirety, of which 10 articles studying 1963 implants met all prospective inclusion criteria for analysis. Overall survivorship of all implants was 93.0% (95% confidence interval, 85.2-96.9) using a random effect model. There was significant heterogeneity between the studies (Q = 131.504). Meta-regression identified an inverse relationship between survivorship and study follow-up duration (p < .0001). Furthermore, age (p = .36) and implant type (fixed-bearing [95.6%, 95% confidence interval, 85.9-98.7] versus mobile-bearing ]89.4%, 95% confidence interval, 79.6%-94.8%]) did not have a statistically significant impact on survivorship, p = .213. However, patients with higher preoperative functional scores had improved survivorship (p = .001). Complications were inconsistently reported with varied definitions. In order of reported frequency, complications were classified into technical error (28.15%), subsidence (16.89%), implant failure (13.28%), aseptic loosening (6.3%), intraoperative fracture (5.67%), wound problems (4.3%), deep infection (1%), and postoperative fracture (0.0001%). Overall study quality was low, with only 10% being prospective and 90% from nonregistry data. The results from this meta-analysis revealed a promising overall survivorship of current implants in use for total ankle replacement; however higher quality studies with standardized outcomes measures are needed.

Keywords: ankle implant; ankle replacement; arthroplasty; survivorship; total ankle replacement.