Fixed-bearing versus mobile-bearing total ankle replacement survivorship. A meta-analysis

Abstract

BackgroundMain objective of this research is to know if there is a different survival rate between fixed bearing (FB) and mobile bearing (MB) total ankle replacement (TAR). We hypothesized that there are no differences between the survival rates of both implants. MethodsA systematic search was performed in PubMed, Cochrane, EMBASE and ClinicalTrials.gov databases‎ to identify published studies from August 2018 to September 2022 including results for FB and MB TAR survivorship. Inclusion criteria included 1) primary TAR in one or both feet in which implant could be identified‎, 2) a minimum of 20 procedures reported, 3) reported implant survivorship or calculable and 4) a minimum of 12 months follow-up for level 1–3 studies or 60 months for level 4 studies. Results3902 ankles in 28 studies were included. 719 were FB and 3104 MB with an overall survivorship of 94% (95% CI [0.89; 0.97]) and 89% (95% CI [0.86; 0.92]) respectively. After subgroup analysis, we did not find differences among both groups (p = ‎0.429‎). Meta-regression analysis showed that longer follow-up was associated with lower survival rates in MB group (p = 0.000) while no other relationships were found with other factors (age, level of evidence or conflict of interests). ConclusionsNo differences in survival rates between both groups were found. Age and other studied confounders were not found to be related with implant survivorship. However, longer follow-up was found to be related with lower survival rates. Studies with longer follow-up and higher level of evidence are needed to confirm results. Level of evidenceIV, systematic review of level I to IV studies.