Clinical outcomes of coronal shear fractures of the distal humerus associated with olecranon fractures.

Background: Coronal shear fracture (CSF) of the distal humerus is rare, accounting for approximately 1% of elbow fractures; cases combined with olecranon fracture are even rarer. This study aimed to clarify the relationship between surgical methods and clinical outcomes in this uncommon injury. Methods: Between 2017 and 2025, we retrospectively reviewed 8 patients (8 elbows) with CSF associated with olecranon fracture who underwent open reduction and internal fixation in a multicenter case series and were followed for more than 6 months. Patient demographics, fracture classifications, surgical methods, postoperative complications, additional surgeries, elbow range of motion, and Mayo Elbow Performance Score at the final follow-up were analyzed descriptively. Results: The mean age was 64 years (range, 51-79 years), and the mean follow-up was 27 months (range, 10-96 months). Dubberley classification was type 2A in 2 cases, type 3A in 2, and type 3B in 4. A posterolateral extended approach was used in 6 patients and a combined lateral-posterior approach in 2. Postoperative complications included elbow release in 2 cases and ulnar neuropathy in 2. At final follow-up, the mean Mayo Elbow Performance Score was 92.5 (range, 75-100), and the mean range of motion was -21°/121.3°. Conclusion: Outcomes of CSF with concomitant olecranon fracture appeared to depend on CSF severity, and complications were more frequent than in isolated CSF. Given the small sample size and observational design, these findings should be regarded as preliminary and hypothesis-generating rather than definitive evidence favoring any particular method.