Complete Recovery of Radial Nerve Function with Long Proximal Origin Early Cable Nerve Grafting

Recovery following cable nerve grafting of mixed nerve defects ranges from complete to total absence of recovery, depending on a number of well-recognized variables. The age of the patient, the level of injury, the length of the grafts, and the time from injury to surgery are usually recognized as the most powerful and controlling variables in the equation of recovery. The manner in which many series on nerve grafting have been published, causes the trends in the primary variables to be well-known, but does not do a good job of clearly delineating a borderline across which expectations for recovery drop off. Radial nerve motor deficits can be treated very successfully with tendon transfers, and the sensory loss is non-discriminative. If the expectation for good motor recovery with cable nerve grafting is uncertain, then the donor-site morbidity of the sural nerve harvest and the time spent awaiting recovery may not appear worth it for some patients.

This report was of two cases that were considered to be near the unclear borderline for expectation of recovery based on a very proximal level of injury and lengthy defects requiring grafting. Both patients were males with high-energy open radial shaft fractures at an unusually proximal level with the spike from the fracture exiting posterolaterally through the radial nerve to create an open wound. Patient ages were 11 and 27 years. Time from injury to surgery was 19 weeks and 12 weeks, respectively. Level of proximal nerve junction was 18 cm and 25 cm proximal to the lateral epicondyle, respectively. Four sural nerve cables were used to graft defects of 8 cm and 11 cm. Time from surgery to recovery of medical research council 5/5 motor power of all radial innervated muscles was 31 weeks and 62 weeks, respectively.

In healthy patients without systemic co-morbidities in whom the most refined principles of nerve reconstructive microsurgery have been followed without ensuing complications, there is no reason why cases with the exact same values for all the major variables should not achieve fairly uniform results. A powerful database shared by reconstructive microsurgeons would allow one to match the values from all four variables to known recovery rates and thus sharpen the borderlines at which recovery is expected.