Long-term outcome of nonunion of the lateral humeral condyle fracture in children: a multicentre retrospective study

Abstract

Purpose: Lateral humeral condyle nonunion in children is a rare condition. The treatment protocol for nonunion of lateral humeral condyle remains controversial due to the potential complication. This study reports long-term functional outcomes of the nonunion of the lateral humeral condyle fracture. In addition, we identified the prognostic factors for nonunion of the lateral humeral condyle fracture. Methods: We conducted a multicentre retrospective cohort study of nonunion of lateral humeral condyle between January 1995 and December 2022. The patient’s preoperative demographic information was reviewed. Potential risk factors of poor functional outcome, such as age, duration from initial injury, and fracture displacement, were retrieved. Functional outcomes at the latest follow-up visit were evaluated using the Mayo Elbow Performance Score (MEPS). Multivariable linear regression was deployed to evaluate the association of potential risk factors with the functional outcome. Results: A total of 63 patients from eight medical centers were included, of which 60 were surgically treated. Patients’ average age was 7.3 years old, with a mean follow-up duration of seven years. All nonunion cases were successfully treated, resulting in a normalized humeroulnar angle. The rate of AVN was 16.7%. All patients reported excellent range of motion and MEPS at the latest follow-up. Multivariable linear regression demonstrated that Fracture displacement (β = -0.88, 95% CI -1.55 to -0.22, p = 0.010) and duration from initial injury (β = -0.09, 95% CI -0.17 to -0.02, p = 0.010) were statistically significant factors influencing functional outcome of lateral humeral condyle nonunion. Conclusions: Initial fracture displacement and duration from the initial injury are statistically significantly associated with elbow function in lateral humeral condyle nonunion. However, the effect size for these factors is relatively small and does not reach clinical significance. Despite this, the functional outcome is excellent in all patients, with an average follow-up duration of seven years.