Efficacy of Intra-Operative Hematoma Blocks Before Spica Casting of Pediatric Femoral Shaft Fractures: A Pilot Study

Background Femoral shaft fractures are a common cause of pediatric orthopedic hospitalization. In children aged 6 months to 5 years, treatment typically involves fracture reduction and hip spica casting. The use of hematoma blocks for perioperative pain management has shown efficacy in other settings but has not been evaluated in pediatric femoral shaft fractures treated with spica casting. Methods A retrospective cohort study was conducted at a single institution as a pilot study to determine the feasibility of a larger multicenter randomized control trial. The study included 35 pediatric patients with femoral shaft fractures treated with hip spica casting from 2018 to 2020. Patients were divided into two groups based on whether they received an intraoperative hematoma block (n=20) or not (n=15). The primary outcome was 24-hour perioperative opioid consumption measured in morphine milligram equivalents (MME). Secondary outcomes included operative time, complications, and fracture healing. Results Patient demographics were similar between groups. The hematoma block group had lower total 24-hour MME use (2.51 vs 2.71), although not statistically significant (P=.76). Weight-based opioid use was the same in both groups (0.18 MME/kg; P=1.0). Mean operative time was significantly longer in the hematoma block group (31.9 vs 26.1 minutes; P=.046). Conclusions Intraoperative hematoma blocks in pediatric femur fractures treated with spica casting were not associated with a statistically significant reduction in perioperative opioid consumption. Although safe, they added a small but statistically significant increase in operative time. A post-hoc analysis power analysis indicated 300 patients would need to be included to detect a statistically significant difference in opioid consumption, suggesting a larger multi-center randomized control trial would be beneficial in validating the use of hematoma blocks with spica casting.