Locking Compression Plate Distal Ulna Hook Plates as Alternative Fixation for Avulsion Fractures of the Tip of the Lateral Malleolus

Abstract Background: Because of the fragment size and inferior location of the fracture lines, options are lacking for internal fixation to treat avulsion fractures of the tip of the lateral malleolus. Because the anatomical architecture of the distal malleolus is similar to that of the distal ulna metaphysis, the purpose of this study was to assess the effectiveness of 2.0-mm locking compression plate distal ulna hook plates in treating avulsion fractures of the tip of the lateral malleolus.Methods: Given the characteristics of the 2.0-mm locking compression plate distal ulna hook plate, cases in which the distance between the fracture lines and the distal end of the tip of the lateral malleolus was less than 6 mm were excluded. Seventeen patients (AO Foundation/Orthopaedic Trauma Association (AO/OTA) 44A fractures, 13 males, 4 females, median age 41 years range 18-73 years) with avulsion fractures of the tip of the lateral malleolus were included. All patients were treated with fixation of the fragment to the fibula using a 2.0-mm locking compression plate distal ulna hook plate. Clinical and radiological follow-up visits were conducted at 6 weeks and 3, 6, 12 and 24 months after the operation. Results: The mean American Orthopedic Foot and Ankle Society Ankle-Hindfoot score of the patients was 97.06±1.92 (range 94 to 100) at the 12-month postoperative follow-up and 97.71±1.54 (range 96 to 100) at the 24-month postoperative follow-up. The mean Karlsson score was 94.18±3.88 (range 90 to 100) at the 12-month postoperative follow-up and 96.43±2.34 (range 95 to 100) at the 24-month postoperative follow-up. Nonunion was not noted; 6 patients complained of lateral malleolar discomfort and foreign body sensation, and 3 of these patients underwent a hardware removal operation at 12 months postoperatively. All patients were clinically and radiographically stable.Conclusion: A 2.0-mm locking compression plate distal ulna hook plate achieved stable and anatomically suitable fixation and should be considered as an alternative treatment for avulsion fractures of the tip of the lateral malleolus.