Is there a safe zone to avoid superficial radial nerve injury with Kirschner wire fixation in the treatment of distal radius? A cadaveric study.

Abstract

To determine the relation of the superficial radial nerve to bony land-marks and to identify a safe zone for K-wire pinning in the distal radius. The superficial radial nerve was dissected in sixteen upper extremities of preserved cadavers. We found that the superficial radial nerve emerged from under brachioradialis at a mean distance of 8.45(±1.22)cm proximal to the radial styloid. The mean distance from the first major branching point of the superficial radial nerve to the radial styloid were 4.8±0.4cm. All branches of the superficial radial nerve were found to lie in the radial half of an isosceles triangle formed by the radial styloid, Lister's tubercle and the exit point of the superficial radial nerve. There is an elliptical area just proximal to the Lister's tubercle. This area is not crossed by any tendons or nerve. It is bounded by the extensor carpiradialis brevis, extensor pollicis longus. Pinning through the radial styloid is unsafe as the branches of the superficial radial nerve passé close to it. The ulnar half of the isosceles triangle is safe regarding the nerve. The elliptical zone just proximal to the Lister's tubercle is safe regarding the tendons and nerve.