Topographic anatomical landmarks for targeted nerve infiltration in distal radius fracture surgery

The study focuses on the increasing incidence of distal radius fractures, particularly in individuals under 15 and over 50, and the critical need for effective perioperative pain management strategies. Distal radius fractures often require surgical intervention and pain control, essential to enhancing recovery and minimizing complications like chronic regional pain syndrome (CRPS). Standard analgesic options include hematoma blocks, Intravenous regional anesthesia (IVRA), regional nerve blocks, sedation, and general anesthesia. This research proposes a nerve block approach targeting the anterior interosseous nerve (AIN), posterior interosseous nerve (PIN), and superficial branch of the radial nerve (SBRN) following open reduction and internal fixation (ORIF) for distal radius fractures, as a potential strategy to improve pain relief and reduce CRPS risk. The study involves anatomical dissection of 15 cadaveric specimens to examine forearm nerve courses relevant to pain management in distal radius fractures. Landmarks were precisely mapped to optimize local anesthetic infiltration. Reference points were set 70 mm proximal to Lister's tubercle along the radial and ulnar edges of the radius, measuring nerve distances and anatomical positions. The SBRN had a mean fascial exit point 69.8 mm from Lister's tubercle and was located radially in 53.3% of cases and palmarly in 46.6%. The AIN was located 4.7 mm from the ulnar border and lay radial to the anterior interosseous artery in 80% of cases. The PIN was, on average, 6.7 mm from the ulnar border and ulnar to the artery in 63.6% of cases. This study identified anatomical landmarks to guide local anesthetic injections near the SBRN, PIN, and AIN to improve pain control after ORIF. LEVEL OF EVIDENCE: Level V: This study is based on anatomical preparations and expert recommendations, without clinical patient studies.