Influence of Implant Design on Clinical Outcomes,Complications,and Revisions Rate in Anterior Approach Total Ankle Arthroplasty A Systematic Review and Meta-Analysis

Abstract

Background

Total ankle arthroplasty (TAA) is increasingly used as an alternative to arthrodesis for end-stage ankle arthritis. The extent to which implant bearing type and design evolution influence outcomes and survival remains debated.

Methods

A systematic review and meta-analysis was conducted in accordance with PRISMA guidelines and registered on PROSPERO (CRD420251073944). PubMed, Embase, and Scopus were searched for English-language studies (2004-2025) reporting anterior-approach TAA with specified implant generation (I–IV) and bearing type (fixed [FB] vs mobile [MB]). Studies with a QualSyst score ≥ 75% were included. Primary outcomes were American Orthopaedic Foot & Ankle Society (AOFAS) score, visual analogue scale (VAS), range of motion (ROM), complications, and revisions.

Results

Forty-two studies comprising 4,271 implants were analyzed (FB: 1,546; MB: 2,725). Functional improvements were mainly driven by implant generation rather than bearing type. ΔAOFAS increased from 33.7 ± 22.3 in Gen II to 44.5 ± 28.3 in Gen IV (P < .001). ΔVAS varied across generations (Gen II 5.8 ± 2.1; Gen III 4.6 ± 2.8; Gen IV 5.46 ± 1.60; all P < .001 vs baseline). MB implants showed lower pre- and postoperative AOFAS scores but comparable ΔAOFAS to FB designs (36.4 vs 37.5; P = .358). MB systems provided greater pain relief (ΔVAS 5.62 vs 4.60; P < .001) but had higher revision rates (12.0% vs 6.2%; P < .001). FB implants achieved superior postoperative ROM gains in plantarflexion (+6.0° vs −2.9°; P < .001) and dorsiflexion (+2.71° vs +0.75°; P < .001). Excluding Gen I, complication rates decreased from 32.6% in Gen II to 18.8% in Gen III and 10.3% in Gen IV (all P < .01); revision rates declined from 16.5% (Gen II) and 9.6% (Gen III) to 0.5% (Gen IV) (P < .01).

Conclusions

Implant generation is the primary determinant of outcomes, complications, and survival in anterior-approach TAA. Bearing type played a secondary role: MB devices provided greater pain relief, whereas FB systems achieved superior ROM recovery and lower revision risk. Fourth-generation implants yielded the most reliable results. Further prospective studies with standardized functional and kinematic assessments are warranted.

Level of Clinical Evidence:

Level I—Systematic Review/Meta-Analysis