PARALYSIS OF THE RADIAL NERVE AFTER HUMERAL SHAFT FRACTURES: SURGICAL REPAIR IN 30 CASES

Abstract

Purpose: Radial paralysis is a major complication of humeral shaft fractures. In most cases, the paralysis is regressive but in certain patients surgical repair is required to achieve full neurological recovery. We reviewed retrospectively our patients to determine the causes of non-recovery and evaluate the efficacy of different treatments.

Material and methods: Thirty patients were operated between 1990 and 1997 for radial nerve paralysis that was observed immediately after trauma or developed secondarily. Mean follow-up after surgery was 6.3 years. There were 22 men and 8 women, 16 right side and 14 left side. Mean delay from injury to surgery was four months (0–730 days). Elements that could be involved in radial paralysis were noted: type of fracture, level of the fracture, treatment, approach, material used. There were ten cases with non-union. Neurological recovery at three years was assessed with muscle tests and with the Alnot criteria. An electrical recording was also made in certain patients. Surgery involved neurolysis in 23 cases, nerve grafts in five and tendon transfers in two.

Results: Outcome was very good and good in 22 patients, good in one and could not be evaluated in one (tendon transfer). There were three failures (two neurolysis and one graft) and two patients were lost to follow-up. After neurolysis, mean delay to recovery was seven months; it was 15 months after nerve grafts. Recovery always occurred proximally to distally.

Discussion: Radial paralysis after femoral shaft fracture regresses spontaneously in 76% to 89% of the cases, depending on the series. There is a predominance in the 20 to 30 year age range. Several factors could be involved in radial paralysis (fracture of the distal third of the humerus, spiral fracture, plate fixation, nonunion). The anterolateral approach allows a better exposure of the nerve. Unlike other authors, we do no advocate exploration of the injured nerve during surgical treatment of the fracture because it is most difficult to determine the potential for recovery of a continuous nerve.

Conclusion: The risk of radial nerve paralysis is greatest for spiral fracture of the distal third of the humerus. In such cases, it may be useful to explore the nerve during the primary procedure and insert a plate. For other cases, we prefer to wait for spontaneous nerve recovery. If reinnervation is not observed at 100 days, we undertake exploration.