Variation in the Bifurcation of the Radial Nerve: Clinical Implications

Abstract

The radial nerve, in the cubital fossa, bifurcates into the deep and superficial branches serving a vital role in providing innervation for the extensor muscles in the forearm and hand. Studies have shown radial nerve injuries are the most common cases associated with fractures of the humeral shaft. While previous studies have focused on the effect of the fracture on the innervation of the radial nerve, few have emphasized the variations of the bifurcation of the radial nerve and if it can be relied upon as a landmark when treating such injuries. This study examines 48 donor body arms. Using a digital caliper, the location of the bifurcation of the radial nerve was measured from the lateral epicondyle of the humerus. In addition, it was noted whether the bifurcation occurred above, at or below a horizontal line drawn between the epicondyles across the cubital fossa. Results show a mean distance from the lateral epicondyle to the bifurcation of 253.4mm, with a standard deviation of 5.39mm. 12.5% of the radial nerves examined bifurcated above the horizontal line and 16.67% bifurcated below the line. Only one sample exhibited a statistically significant deviation from the rest of the samples (p <.05, CI 242.83–263.97). These findings suggest that despite variations in the bifurcation of the radial nerve longitudinally, the bifurcation can be confidently predicted within a certain absolute distance from the lateral epicondyle.Grant Funding Source: NA