Hybrid Fixation for Syndesmotic Stabilisation: A Systematic Review of Clinical and Biomechanical Evidence.

Abstract

<b>Background:</b> Syndesmotic injuries are a common type of ankle trauma, occurring in isolation or with fracture. Hybrid fixation (HF) combines screw and dynamic fixation, either as separate implants or within an integrated device, to stabilise such injuries. Despite clinical interest, no comprehensive evidence synthesis exists. This review evaluates clinical and biomechanical evidence on HF for syndesmotic stabilisation. <b>Methods</b>: EMBASE, Medline, the Cochrane Library, and PubMed databases were systematically searched until May 2025 to identify studies reporting HF in adults with syndesmotic injury. Clinical studies were appraised using the Methodological Index for Non-Randomised Studies (MINORS) and biomechanical studies using the Quality Appraisal for Cadaveric Studies (QUACS) tool. Given variation in HF configuration and outcome reporting, qualitative synthesis was performed in accordance with PRISMA 2020 guidelines. <b>Results</b>: Six studies were included: four clinical and two biomechanical. Across clinical studies, 93 patients received HF. Mean American Orthopaedic Foot and Ankle Society (AOFAS) scores, reported in two studies, were 93.3 at final follow-up. Radiographic outcomes indicated maintained syndesmotic reduction. Malreduction occurred in 3 patients (3.2%), unplanned implant removal in 3 patients (3.2%), and implant failure in 14 patients (15.1%). All implant failures were asymptomatic and confined to one study. Biomechanical studies demonstrated that HF restored native joint kinematics under simulated loading. <b>Conclusions</b>: Current evidence supports HF as an appropriate syndesmotic fixation strategy. However, methodological limitations of the available evidence, including observational design and variable follow-up durations, should be considered. Heterogeneity in construct design, inconsistent outcome reporting, and limited comparative research complicate interpretation. Future research should prioritise standardised outcome reporting and longer follow-up to thoroughly evaluate HF.