Daytime vs. Nighttime Surgery for Pediatric Supracondylar Humerus Fractures: A Retrospective Cohort Study.

Background/Objectives: The objective was to evaluate whether surgical timing (daytime vs. nighttime) influences intraoperative and postoperative outcomes in pediatric supracondylar humerus fractures. Methods: A retrospective observational cohort study was conducted at a tertiary center. Pediatric patients aged ≤14 years who underwent surgery for supracondylar humerus fractures between January 2010 and December 2022 were included. Fractures were classified according to the Gartland system. Patients with open fractures, associated neurovascular injury, compartment syndrome, or incomplete follow-up were excluded. Primary outcomes included need for open reduction, reoperation, neuropathy, and loss of joint mobility. Patients were grouped according to the time of surgery: daytime (08:00-22:00) or nighttime (22:00-08:00). Stratified analyses were performed based on fracture severity. Results: Eighty-six patients were included: 56 underwent daytime surgery and 30 underwent nighttime surgery. Groups were comparable in age, sex, and fracture severity. Nighttime surgery was associated with a significantly higher rate of open reduction (33.3% vs. 10.7%, p = 0.023; RR = 3.11). Reoperation (16.6% vs. 5.4%, p = 0.121) and postoperative neuropathy (23.3% vs. 8.9%, p = 0.131) were more frequent in the nighttime group, although these differences were not statistically significant. In complex fractures (Gartland III-IV), nighttime surgery was associated with a significantly higher reoperation rate (20.8% vs. 2.6%, p = 0.026). Conclusions: Nighttime surgery was associated with higher rates of open reduction and reoperation, particularly in complex supracondylar humerus fractures. However, given the retrospective design and limited sample size, these findings may be influenced by residual confounding and should be interpreted as exploratory.