Long-term outcomes of suture button vs syndesmotic screw fixation for ankle syndesmotic injuries: A systematic review and meta-analysis of randomized controlled trials.

INTRODUCTION Optimal fixation choice for ankle syndesmotic injuries remains uncertain. Traditional syndesmotic screw (SS) fixation provides rigid stabilization but restricts micromotion and may require secondary removal. Dynamic fixation using suture button (SB) allows physiological motion while maintaining reduction. This study aims to compare the long-term outcomes between SB and SS fixation for ankle syndesmotic injuries.

Methods

This study was conducted according to the PRISMA 2020 guidelines. Literature search was performed through PubMed, ScienceDirect, Cochrane, Google Scholar, and ProQuest for randomized controlled trials (RCTs) with ≥ 24 months follow-up. Primary outcomes were ankle functional scores. Secondary outcomes were pain, reoperation, range of motion, malreduction, and advanced osteoarthritis. Meta-analysis was performed using a random-effects model.

Results

Seven reports from five RCTs involving 339 participants were included. The mean participant age was 43.57 years (95% CI, 40.66-46.48) with follow-up duration of 57.4 months (4.8 years). In the main cohort-level analysis using the latest available follow-up, pooled AOFAS and OMAS scores did not differ significantly between SB and SS fixation, although heterogeneity was substantial. Pain-related outcomes favored SS fixation [SMD -0.56, 95% CI -1.04 to -0.08; I² = 62%], but interpretation was limited by heterogeneity and variation in assessment instruments. The current quality of data available is unable to detect any clinically significant difference in range of motion, study-defined malreduction, or advanced osteoarthritis. Reoperation outcomes were synthesized narratively because implant-removal strategies varied substantially across cohorts.

Conclusion

Current randomized evidence is underpowered to establish long-term superiority of either method of syndesmotic stabilization. Interpretation remains limited by few independent cohorts, heterogeneity, and limited certainty of evidence.