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INTRODUCTION AND IMPORTANCE: Coronal shear fractures of the distal humerus are rare and are expected to have a high incidence of avascular necrosis (AVN) due to the avascular nature of the capitellar bone fragment and limited soft tissue attachment. However, according to the literature published thus far, AVN is infrequently reported, and some studies suggest that it does not have a significant impact on clinical outcomes. CASE PRESENTATION: Two female patients, one aged 72 and the other 70, presented with coronal shear fractures of distal humerus. Both patients were diagnosed with AVN of the capitellum 7 and 10 months after undergoing open reduction and internal fixation. One patient underwent hardware removal, while the other patient declined due to the absence of discomfort. However, at their final follow-up, both patients exhibited good clinical results. CLINICAL DISCUSSION: The occurrence of AVN may be related to the severity of the initial injury, including posterior comminution. While some studies suggest that AVN of the capitellum may not affect clinical outcomes, hardware removal may be required in cases where there is intra-articular protrusion of the hardware. CONCLUSION: Although AVN is a rare occurrence, even when it does occur, it may not significantly affect clinical outcomes. In this study, AVN may be associated with initial injury severity, and surgical treatment may make it possible to develop AVN. Moreover, considering the timing of the occurrence of AVN, it is believed that a close follow-up of more than one year will be required.
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Background: The aim of this study was to introduce a novel technique to improve the ease of fixing of even small fragments of the coronoid process and report the clinical outcomes of this method. Methods: Forty-nine patients with ulnar coronoid process fractures fixed using the hooked Kirschner wire (K-wire) technique at our hospital from 2007 to 2019 were reviewed. Radiological features and fracture union were assessed using simple radiographs. Functional outcomes of the treated elbows were evaluated at the final follow-up visit using the Mayo Elbow Performance Score (MEPS). Results: All patients were examined at a mean follow-up of 17.7 months (range, 6-62 months). We observed bony union in patients at a mean of 10.9 weeks (range, 6-22 weeks). The mean flexion and extension ranges of the elbow were 132.0° (range, 106° -151°) and 4.5° (range, -20° to 30°), respectively. The mean pronation and supination ranges of the forearm were 81.1° (range, 60°-90°) and 88.3° (range, 60°-120°), respectively. The mean arc of the elbow was 127.4° (range, 78°-160°). All patients were evaluated using the MEPS at the final follow-up visit, with a mean score of 96.9 points (range, 80-100 points). One case of coronoid nonunion was observed and re-fixation was performed. One case of infection was observed and also treated with additional surgery. Three patients complained of ulnar nerve symptoms and 1 patient underwent surgical release for tardy ulnar nerve palsy. Conclusions: Despite its limitations, the hooked K-wire technique was a useful method for even smaller coronoid process fractures. K-wires were also a useful temporary intraoperative fixation method and could provide permanent fixation.