Occult syndesmotic malreduction detected by postoperative CT despite acceptable radiographs: Association with...

Plain radiographs are routinely used to assess syndesmotic reduction after ankle fracture fixation; however, their ability to detect subtle malreduction remains uncertain. This study evaluated the prevalence and clinical relevance of CT-detected syndesmotic malreduction in patients with radiographically acceptable postoperative reduction.

Adult patients undergoing ankle fracture fixation with syndesmotic stabilization and acceptable postoperative radiographs were prospectively enrolled. All patients underwent early postoperative bilateral CT assessment with side-to-side comparison of translational and rotational parameters. Patients were stratified into anatomical reduction, minor malreduction, and major malreduction groups. Functional outcomes were assessed at 24 months using the AOFAS ankle-hindfoot score.

Eighty-six patients were included. CT detected syndesmotic malreduction in 52.3% of patients despite acceptable radiographs. Mean AOFAS scores progressively decreased from the anatomical reduction to the major malreduction group (91.3 ± 5.9 vs 83.5 ± 3.5 vs 74.4 ± 3.2; p < 0.001). Both minor and major malreduction were independently associated with worse functional outcomes.

Postoperative radiographs may underestimate syndesmotic malreduction. CT identified occult malreduction in a substantial proportion of cases and demonstrated a significant association between malreduction severity and inferior functional outcomes.

Level II, prospective cohort study.