94 patients with acute femoral shaft fractures scheduled for intramedullary rod fixation were randomized to receive a hematoma block injection (n=47) or a placebo injection (n=47). The primary outcome of interest was pain intensity, measured using a Visual Analog Scale (VAS). The secondary outcome of interest was opioid consumption in morphine milligram equivalents (MME). Outcomes were assessed in the first 24 hours post-operation. Patients who received the hematoma block had significantly lower pain scores and opioid consumption throughout the 24-hour post-operative period. 1 case of quadriceps weakness was reported in the hematoma block group. The results of this study suggest that the performance of a post-fixation hematoma block could be a safe and effective pain management intervention, minimizing the need for opioids.