Approach to radial nerve palsy caused by humerus shaft fracture: is primary exploration necessary?

While recommendations for early exploration and nerve repair in cases of open fractures of the humeral shaft associated with radial nerve palsy are clear, the therapeutic algorithm for the management of closed humeral shaft fractures complicated by radial nerve palsy is still uncertain. The purpose of this study was to determine whether patients with complete sensory and motor radial nerve palsy following a closed fracture of the humeral shaft should be surgically explored.

Twenty-five patients with closed humeral shaft fractures complicated by complete radial nerve palsy were retrospectively reviewed during a 12-year period. Surgical intervention was indicated if functional recovery of the radial nerve was not present after 16 weeks of expectant management.

Surgical exploration was performed in 12 patients (48%) after a mean period of expectant management of 16.8 weeks (range: 16-18 weeks). In 2 of them (10%) total nerve transection was found. In the rest 10 patients underwent surgical exploration the radial nerve was found to be macroscopically intact. All intact nerves were fully recovered after a mean time of 21.6 weeks (range: 20-24 weeks) post-injury. In 13 patients (52%) in whom surgical exploration was not performed the mean time to full nerve recovery was 12 weeks (range: 7-14 weeks) post-injury.

We proposed immediate exploration of the radial nerve in case of open fractures of the humeral shaft, irreducible fractures or unacceptable reduction, associated vascular injuries, radial nerve palsy after manipulation or intractable neurogenic pain. Due to high rate of spontaneous recovery of the radial nerve after closed humeral shaft fractures we recommend 16-18 weeks of expectant management followed by surgical intervention.