Surgical treatment of coronal shear fractures: short- to mid-term results and risk factor analysis

Coronal shear fractures of the distal humerus are rare but severe injuries. Reconstruction is often challenging, especially in comminuted cases, which is why many surgeons opt for an elbow arthroplasty in those cases. However, total elbow arthroplasty is associated with a variety of potential problems itself. Therefore, the aim of this study was to present the functional and clinical outcome of coronal shear fractures treated by osteosynthetic reconstruction in a short- to mid-term follow-up, and to identify possible risk factors for an inferior outcome.

We performed a retrospective follow-up assessment of 51 consecutive patients (30 women; median age 56 years, (IQR 39-62)) who underwent osteosynthetic reconstruction for coronal shear fractures between 2012 and 2022 after a minimum follow-up period of two years. The Mayo Elbow Performance Score, Oxford Elbow Score, and Disabilities of the Arm, Shoulder and Hand score were evaluated, and all available radiographs were analyzed. All complications and revision procedures were assessed. Univariable and multivariate regression analyses were performed to identify potential risk factors for a poor outcome following osteosynthetic reconstruction.

After a median follow-up period of 43 (IQR 28-78) months, the median Mayo Elbow Performance Score was 100 (IQR 85-100), the median Oxford Elbow Score was 42 (IQR 34-46), and median Disabilities of the Arm, Shoulder and Hand score was 6 (IQR 2-28). The median ROM was 148° (IQR 126-155) for flexion, 0° (IQR 0-0) for extension, 90° (IQR 85-90) for pronation, and 90° (IQR 85-90) for supination. There was no extension deficit on the injured site. The overall complication and reoperation rates were 35.3% and 27.4%, respectively, with severe elbow stiffness being the most common reason for revision. Increasing Dubberley classification and posterior comminution were significantly associated with a poor outcome and higher rates of complications and revision.

This short- to mid-term follow-up shows good functional results after osteosynthetic reconstruction in coronal shear fractures despite high complication and revision rates. However, increasing Dubberley classification, posterior comminution and the presence of complications show inferior outcome scores. This study shows that osteosynthetic reconstruction can be an option even in comminuted coronal shear fractures. Nevertheless, patient factors need to be considered and an individual decision concerning the surgical treatment is necessary. Patients should be counseled about the high complication rates and inferior outcome with increasing Dubberley classification.

Level III.