[Delayed radial nerve palsy following a humeral shaft fracture].

We reported a 24-year-old man with right radial nerve palsy. He had suffered from a right humeral shaft fracture approximately three years before. The fracture was treated with intramedullary nailing. Our radiograph of the right upper limb showed callus around the fracture site. A nerve conduction study revealed conduction block of the radial nerve at the lateral side of the callus. Tinel's sign was present in the median nerve at the medial side of the callus. Surgical exploration revealed that the radial nerve trunk was compressed at the callus site. The median nerve trunk was close to the callus. We decompressed radial nerve trunk, and the patient's neurological symptoms improved gradually after the operation. Delayed radial nerve palsy has been reported only rarely, whereas acute compression of the nerve sometimes occurs after humeral shaft fractures. Morever, the median nerve also was vulnerable to compression at the site of callus. These findings underscore the importance of taking into account the possibility of delayed compression neuropathy after humeral shaft fracture.