From the Research
The most common complication of a mid-shaft humerus fracture is injury to the radial nerve. This is due to the radial nerve's close proximity to the humerus, wrapping around the posterior aspect of the bone in the spiral groove, making it vulnerable to injury when a fracture occurs at this level 1. The radial nerve can become stretched, contused, or even entrapped between fracture fragments, leading to radial nerve injury, which occurs in approximately 11-18% of mid-shaft humerus fractures 2.
Key Points
- Radial nerve injury typically presents as wrist drop, with weakness in wrist and finger extension and sensory deficits over the dorsal aspect of the hand.
- Most radial nerve injuries associated with humeral shaft fractures are neuropraxias (temporary injuries) that resolve spontaneously within 3-4 months 3.
- Treatment initially involves splinting the wrist in extension to prevent contractures while awaiting nerve recovery.
- Surgical exploration is generally reserved for cases where there is no improvement after several months or when there is evidence of nerve transection 4.
Comparison of Options
- The brachial artery can also be injured in humeral fractures but is less commonly affected than the radial nerve.
- The axillary artery and median nerve are less likely to be injured in mid-shaft humerus fractures compared to the radial nerve 5.
Recommendation
Based on the most recent and highest quality study, the radial nerve is the most common complication of a mid-shaft humerus fracture 1. Therefore, it is essential to monitor patients with mid-shaft humerus fractures for signs of radial nerve injury and provide appropriate treatment to prevent long-term morbidity.