Factors Influencing Time to Return of Elbow Motion in Completely Displaced and Flexion Type Pediatric Supracondylar Humeral Fractures.

Background: Factors influencing the time to return of elbow motion have not been reported in extension-type III/IV and flexion-type supracondylar humeral (SCH) fractures. This study aims to identify factors influencing the time to return of elbow motion following operative pinning of these injuries. Methods: An IRB-approved retrospective study was conducted of patients <18 years old treated at a large tertiary children's hospital from January 1, 2013 to July 31, 2022 for operatively pinned, completely displaced, and flexion-type SCH fractures. We excluded other SCH fracture types, patients undergoing screw fixation, inadequate documentation, patients with subsequent reinjury following fixation or with loss of reduction, and those requiring additional casting following pin removal. Patients achieving combined elbow extension <30° and flexion >130° were defined as having functional range of motion. Patient-, injury-, operative-, and postoperative factors and time to elbow motion were recorded. Comparison of factors was done using bivariate and multivariate analysis. Results: Postoperative elbow motion data were available for 716 patients, of which 80.3% had functional elbow motion and 19.7% had partial elbow motion recovery. The mean age was 6.3 years and the median time to elbow motion recovery was 35 days. Individual factors significantly associated with elbow motion recovery included: age, neurological deficit at the time of injury, reduction method, number of pins used for stabilization and postpin removal immobilization duration. Factors significant for elbow motion recovery in multivariate analysis were age, neurological deficit, immobilization and open reduction. Conclusions: Older age, neurological deficit at the time of injury, open reduction, and longer duration splint immobilization after pin removal were independently associated with a delay in return to elbow function. Key Concepts: (1)Older patients and those with nerve injuries are at risk for delayed elbow motion after surgical treatment of displaced, flexion-type supracondylar humerus fractures.(2)While open reduction is performed in select cases at the surgeon's discretion, the current study showed it to be independently associated with delayed recovery.(3)Postoperative immobilization, if required, should be used for less than <3 weeks. Level of Evidence: III, Retrospective.