Pediatric Lateral Condyle Fractures Pins or Screw?

BACKGROUND: This prospective observational cohort study evaluates the clinical, radiographic, and functional differences between pins and screw fixation for displaced pediatric lateral condyle fractures of the elbow. METHODS: Skeletally immature patients <18 years with isolated Weiss type 2 and 3 lateral condyle fractures undergoing operative fixation were prospectively enrolled to receive either pins or screw fixation at a single level 1 trauma center. Fixation choice was based on the attending surgeon's preference. Exclusion criteria were concomitant orthopaedic injury at the time of lateral condyle fracture. Patients were followed at 3, 6, 9, and 12 weeks or until fully healed. A non-inferior analytical framework was performed for comparison. RESULTS: A total of 66 patients with pin fixation and 37 patients with screw fixation were studied, with an average age of 6 years (SD 2.6). Patients treated with screw fixation were a mean of 1.5 years older (0.4, 2.4). There was no significant difference in time to radiographic union or odds of a complication. Mean difference in time to radiographic union was 1.5 days in favor of pins (31.6, 38.9) over screws (28.3, 45.3), which remained within the accepted non-inferiority margin. Patients treated with screw fixation had 0.2 odds (0.02, 1.7) of a complication compared with pins, which was not significant. Two patients treated with pins developed nonunion, and 2 developed avascular necrosis, versus none in the screw fixation group. Patients with screw fixation spent 8 fewer days in cast immobilization (-10.6, -5.3). The average time in cast was 31.4 days (SD 6.9) for the pins group and 23.5 days (SD 6.3) for the screw group. There was no significant difference in flexion, extension, or total arc of motion achieved between groups. CONCLUSIONS: Patients with screw fixation were out of casts faster without compromising time to union or elbow arc of motion. There was no significant difference in complications between fixation types; however, 2 patients with pin fixation developed a nonunion. Screw fixation is non-inferior to pin fixation when considering time to radiographic union, complications, and final range of motion achieved. LEVEL OF EVIDENCE: Level II: prospective and comparative study.