Preventing posterior interosseous nerve injury during a distal biceps tendon repair: an anatomic study comparing extensor digitorum communis and extensor carpi ulnaris muscle splitting approaches

The ECU, vs. EDC, muscle splitting approach is less likely to endanger the PIN and/or its branches because the RT-to-PIN length was ≥11 mm longer in all 3 forearm positions (P < .001). Additionally, the PIN crossed the midline of the radial shaft and its approach line using an EDC approach, while only the ECU motor branch transversed the radial shaft and its approach line with an ECU approach. The PIN was located ≥21 mm distal to the RT using an ECU muscle splitting approach in forearm pronation. The ORS line and olecranon are useful landmarks to locate the PIN and RT, respectively.