Are positional screws superior to lag screws in fixation of medial malleolar fractures? A randomized controlled trial.

Purpose: There is no consensus about the best fixation method for medial malleolar fractures. This study was conducted to compare the clinical and radiological results of positional (fully threaded) screws and lag (partially threaded) screws when used to fix medial malleolar fractures.

Methods: This prospective, randomized clinical trial included 68 patients with closed isolated medial malleolar fractures. Each study arm included 34 patients who were randomly treated with either fully threaded screws (FT group) or partially threaded screws (PT group). Patients were evaluated radiologically for union and clinically using the American Orthopaedic Foot and Ankle Society (AOFAS) ankle hindfoot score.

Results: After a 12-month follow-up, the mean AOFAS ankle hindfoot score was 92.1 ± 3.5 in the FT group and 91.8 ± 5.4 in the PT group. Union was achieved in the FT group after a mean of 6.2 ± 1.3 weeks and after a mean of 6.5 ± 1.5 weeks in the PT group.

Conclusion: Both fully threaded and partially threaded screws yielded good comparable clinical and radiological outcomes when used to fix isolated medial malleolar fractures.