Ultrasound-Guided Supracondylar Radial Nerve Block Versus Hematoma Block for Closed Reductions of Distal Radius Fracture in the Emergency Department: A Randomized Controlled Clinical Trial.

Purpose: To compare the analgesic efficacy of hematoma block versus ultrasound guided supracondylar radial nerve block for distal radius fracture reduction and its effect on reduction quality in the emergency department. Methods: A randomized controlled, open label trial, with blinded analysis was conducted. Patients aged 18 years or older with a diagnosis of acute distal radius fracture (<1 week) were included. Pain perception was measured using the numeric rating scale at three distinct time points: at admission (M0), 10 minutes after the analgesic intervention (M1), and during the reduction maneuver (M2). Standard radiographic measurements were recorded before and after fracture reduction. Complications were registered both during the hospital stay and via telephone follow-up at 2 weeks. A descriptive analysis of the demographic variables was performed. Fisher exact test was estimated to evaluate differences between groups. Relative risk and absolute risk difference with 95% CI, number needed to treat, or number needed to harm were estimated for M0-M1, M1-M2, and M0-M2 and for each reduction quality parameter. Results: Fifty patients were analyzed, including 28 in the intervention group and 22 in the control group. Most patients were female with a median age of 62 years (IQR 18.25). There was not clinically significant improvement of pain (≥ 2 on the numeric rating scale) between pain at admission (M0) and after analgesic intervention (M1), or between analgesic intervention (M1) and reduction maneuvers (M2) among groups. Ultrasound-guided supracondylar radial nerve block was associated with clinically significant pain improvement between admission (M0) and reduction maneuvers (M2). No statistical differences were observed in reduction quality between groups for each radiographic parameter. Conclusions: Ultrasound-guided supracondylar radial nerve block was associated with improved pain during reduction compared to pain at admission, relative to hematoma block. No differences were observed in reduction quality among groups. Type of study/level of evidence: Therapeutic IB.