Percutaneous Screw Fixation for the Management of Delayed Unions in Pediatric Lateral Humeral Condylar Fractures.

Background: The use of in situ screw fixation for the treatment of pediatric lateral humeral condyle (LCH) delayed unions has recently been reported. While attractive, the currently available literature consists of small retrospective studies with mixed results. As such, the present study aims to describe the outcome of a group of children with delayed unions of LCH fractures treated with in situ fixation using a single, percutaneously placed cannulated screw in compression.

Methods: A retrospective review of all pediatric patients (below 18 y) with lateral condyle fractures of the humerus treated surgically for delayed union between 2013 and 2023 at a single, tertiary referral center was completed. Clinical and radiologic variables related to the initial injury and delayed union were abstracted from the medical record, as were surgical variables. Radiographs were evaluated for union postoperatively; time to union was determined by the senior authors. Descriptive statistics were used to summarize demographic and outcome variables.

Results: A total of 12 consecutive patients met the inclusion criteria. The mean age at the time of initial injury was 5.6 years; subjects were followed for a mean of 3.0 years following initial presentation. All were treated with a single, percutaneously placed screw in compression at a mean of 10.5 months after the original injury. Radiographic union was achieved in 11 (91.7%) patients. At the latest follow-up, all patients were pain free and demonstrated a functional arc of motion without evidence of avascular necrosis. A total of 2 patients required revision for loss of fixation. In one patient, a persistent lucent line was observed, and 1 patient was found to have a cubitus valgus deformity, both of which were not clinically relevant.

Conclusions: Our results suggest that with the use of proper technique (a 4.5 cannulated screw inserted through the metaphyseal portion of the lateral condyle fragment, engaging the most medial/distal aspect of the humeral shaft), radiographic union and clinical healing can be achieved in the majority of patients. Percutaneous screw fixation should be considered as an option for cases of noninfected pediatric lateral condyle delayed unions.

Level of evidence: Level IV-evidence therapeutic studies.