Posteromedial elbow dislocations without relevant osseous lesions: Clinical characteristics, soft-tissue injury patterns, treatments, and outcomes

Background: Although simple posterolateral or posterior elbow dislocations are relatively common and usually stable after closed reduction, simple posteromedial dislocations are extremely rare and poorly characterized. We investigated the clinical characteristics, soft-tissue injury patterns, treatments, and outcomes of a series of posteromedial elbow dislocations without relevant osseous lesions. Methods: We retrospectively reviewed 20 cases of simple posteromedial elbow dislocations without relevant osseous lesions that were treated at 7 fellowship training hospitals during a 10-year period. Soft-tissue injury patterns in 15 cases were investigated with use of magnetic resonance imaging. Clinical outcomes were evaluated after an average of 56.1 months (range, 24 to 93 months) with use of the Mayo Elbow Performance Score (MEPS) and the Quick-DASH (an abbreviated version of the Disabilities of the Arm, Shoulder and Hand [DASH]) score. Complications were also evaluated. Results: On magnetic resonance imaging, significant tears of the lateral collateral ligament complex and common extensor group were observed in all cases. Seventeen cases (85%) required surgical treatment for acute instability. Fourteen cases underwent only lateral complex repair and 3 underwent repair of both the medial and lateral complexes. At the time of the latest follow-up, the mean MEPS and Quick-DASH scores were 85.8 ± 15.0 and 10.5 ± 16.3, respectively. Seventeen patients (85%) had a satisfactory clinical outcome. Complications following treatment included 4 patients with heterotopic ossification; 2 of these patients also experienced posttraumatic elbow stiffness, which was treated with arthrolysis at 8 and 18 months after the initial operation. Conclusions: Posteromedial elbow dislocations without relevant osseous lesions are associated with a more severe soft-tissue injury, especially to the lateral complex, resulting in a high rate of surgical treatment. With careful post-reduction evaluation, either operative or nonoperative treatment provided satisfactory clinical outcomes.