Functional and Radiological Outcomes of Suture-Button versus Syndesmotic Screw Fixation in Distal Tibiofibular Syndesmotic Injuries: A Prospective Comparative Study

Abstract

Background: Acute disruption of the distal tibiofibular syndesmosis is a common and clinically important component of unstable ankle injuries that requires anatomical reduction and rigid fixation to restore function and prevent late post-traumatic arthritis. Conventional rigid syndesmotic screw fixation has been the long-standing standard but is associated with implant prominence, the need for routine hardware removal and a recognised risk of malreduction. Dynamic suture-button devices have emerged as a flexible alternative that may better reproduce physiological syndesmotic motion. The present study compared the functional and radiological outcomes of suture-button and syndesmotic screw fixation in adults with acute distal tibiofibular syndesmotic injuries. Methods: A prospective comparative study was conducted in a tertiary care orthopaedic unit. Eighty consecutive adult patients with acute unstable syndesmotic injuries (Lauge-Hansen supination-external rotation type IV or pronation-external rotation injuries) were sequentially allocated to either suture-button fixation (n = 40) or 3.5 mm tetracortical syndesmotic screw fixation (n = 40) following anatomical reduction of associated fractures. The primary outcome was the American Orthopaedic Foot and Ankle Society (AOFAS) Ankle-Hindfoot score at 12 months. Secondary outcomes included the Olerud-Molander Ankle Score, radiological reduction parameters, time to functional milestones, complications and the need for hardware removal. Results: Both groups were comparable at baseline. At 12 months, the mean AOFAS score was significantly higher in the suture-button group (92.4 ± 6.8 versus 87.2 ± 8.4; p = 0.003), as was the Olerud-Molander score (88.4 ± 7.2 versus 81.2 ± 9.6; p = 0.001). Patients in the suture-button group achieved full weight-bearing earlier (6.4 ± 1.2 versus 9.8 ± 1.8 weeks; p < 0.001) and returned to previous occupation and recreational activities sooner. Loss of reduction was less frequent in the suture-button group (5.0% versus 22.5%; p = 0.024). Hardware removal was required in 47.5% of screw-fixation patients compared with only 7.5% of suture-button patients (p < 0.001). Conclusion: Dynamic suture-button fixation produced superior functional and radiological outcomes compared with conventional rigid syndesmotic screw fixation in acute distal tibiofibular syndesmotic injuries, with earlier return to function, fewer complications and a markedly lower requirement for secondary hardware removal. These findings support the routine use of suture-button devices as the preferred fixation strategy for acute unstable syndesmotic injuries.