Comparison of two versus three-screw fixation for biplanar chevron medial malleolar osteotomy.

ABSTRACT

PURPOSE: This study was designed to compare the clinical outcomes and complications of using two versus three screws to fix the biplanar chevron medial malleolar osteotomy (MMO). PATIENTS AND METHODS: A retrospective review was conducted on 43 patients (46 ankles) who underwent biplanar chevron MMO to treat talus osteochondral lesions. Of these, MMO was fixed with two parallel screws placed perpendicular to the osteotomy plane in 16 ankles, while in the remaining 30 ankles, MMO was secured with two parallel screws plus an additional third screw inserted parallel to the tibial plafond. Patients were divided into two groups based on the fixation method and clinical outcomes, union and malunion rates, and complications were compared. RESULTS: Demographic and clinical characteristics such as age (p 0.411), gender distribution (p 0.119), affected side (p 0.126), lesion grades (p 0.056), and lesion sizes (p 0.310), immobilization (p 0.119) and weight-bearing periods (p 0.252) were statistically similar across both groups. Initial malreduction were observed in five cases within the three-screw group and one case in the two-screw group (p 0.307). However, neither group exhibited any progressive step-off or gap in the follow-up radiographs, and osteotomy union was achieved in all patients. Delayed union was observed in one patient from the three-screw group. Significant improvements in American Orthopedic Foot and Ankle Society scores were observed in both groups, with no functional discrepancies evident at the final follow-up (p 0.488). CONCLUSIONS: The study found no significant differences in union rates, complications, or clinical outcomes between two and three-screw fixation methods for medial malleolar osteotomies (MMO). Both methods allowed for effective MMO fixation without loss or displacement post-surgery, suggesting their safety and efficacy. LEVEL OF EVIDENCE Level III, retrospective comparison.