Outcomes Following Early Weight Bearing in Syndesmotic Injuries: A Randomized Controlled Trial.

OBJECTIVES: To compare outcomes of early weight bearing (EWB) at 2-weeks versus delayed weight bearing (DWB) at 6-weeks following operative ankle fracture fixation with syndesmotic stabilization.

METHODS: Design: Prospective randomized controlled clinical trial.

SETTING: Single Level 1 Trauma Center.

PATIENT SELECTION CRITERIA: Adult patients with operative rotational ankle fractures (OTA/AO 44A-C) and an intraoperative finding of syndesmotic injury following fracture fixation between September 2019 and September 2022 were included. All underwent dynamic syndesmotic stabilization utilizing a single suture button. Exclusion criteria were fibular fractures not amenable to length-stable fixation (e.g., Maisonneuve injuries), neuropathic diabetes, body weight ≥147.4 kg (325 lbs), imprisonment, pregnancy, lactation, end-stage renal disease, cognitive dysfunction, or polytrauma.

OUTCOME MEASURES AND COMPARISONS: Maintenance of syndesmotic reduction at 1 year comparing immediate postoperative and 1-year CT scans of both ankles was the primary outcome. Secondary outcomes: pain (VAS), surgical satisfaction (SSQ-8), functional scores (AAOS Foot and Ankle), ankle range of motion, and complications.

RESULTS: 106 patients were enrolled: 40 underwent syndesmotic fixation and were randomized. 16 patients (mean age 41 (21-80), 9 female, 7 male) randomized to EWB and 23 (mean age 43 (23-85), 12 female, 11 male) to DWB completed the study. Fracture types included lateral malleolar (OTA/AO 44A), bimalleolar and bimalleolar equivalent (OTA/AO 44B), and trimalleolar (OTA/AO 44C) fractures, with similar distribution between groups (p=0.96). EWB group had significantly higher pain scores (4.6 ± 2.8 vs 2.8 ± 2.3, p = 0.039) at the 2-week visit compared to DWB. At 1 year, dorsiflexion in the EWB group was significantly higher (14.2° ± 3.9° vs 7.7° ± 4.4°) than the DWB (p = 0.017). No significant difference in syndesmotic malreduction (p>0.99), loss of reduction (p>0.89), PROs, development of arthritis (p>1.0) or complication rates (p>0.37) at any other timepoint.

CONCLUSIONS: Early weight bearing at 2-weeks was noninferior to delayed weight bearing at 6-weeks following rotational ankle fracture fixation with a syndesmotic injury stabilized with flexible fixation.

LEVEL OF EVIDENCE: Level I.