From the Research
In a patient with a distal radius fracture, you should test the function of several key muscle groups to assess for associated nerve injury or compartment syndrome, including the median nerve, ulnar nerve, radial nerve, and anterior interosseous nerve, as these injuries can lead to significant morbidity and impact quality of life 1. When evaluating a patient with a distal radius fracture, it is essential to consider the potential for nerve injuries, which can occur due to direct trauma, compression from swelling, or compartment syndrome.
- The median nerve should be evaluated by testing thumb opposition (opponens pollicis), thumb abduction (abductor pollicis brevis), and index finger flexion at the distal interphalangeal joint (flexor digitorum profundus) 2.
- The ulnar nerve should be assessed by checking finger abduction/adduction (interossei) and little finger opposition (opponens digiti minimi).
- For the radial nerve, evaluate wrist extension (extensor carpi radialis longus and brevis), finger extension (extensor digitorum), and thumb extension (extensor pollicis longus and brevis) 3.
- Additionally, evaluate the anterior interosseous nerve by testing the "OK" sign (flexor pollicis longus and flexor digitorum profundus to index finger), as flexor pollicis longus tendon rupture is a rare but serious complication of volar plate fixation performed for distal radius fractures 4. This comprehensive muscle testing is crucial because distal radius fractures can be associated with nerve injuries, and early detection of neurological deficits allows for timely intervention, potentially preventing permanent functional impairment and reducing morbidity and mortality 1, 5. Document your findings as a baseline for comparison during follow-up evaluations to ensure the best possible outcome in terms of quality of life.