Answer and Explanation 6

6.  Choice D is the correct answer.  Patients with mid shaft humerus fractures can get injuries of the radial nerve that can lead to wrist drop.  The median nerve provides sensory innervation and some motor to digits 1-3 and lateral half of the 4th on the volar surface.  It also provides innervation to the tips  of the fingers.  This is the nerve afflicted with carpal tunnel syndrome.  The ulnar nerve supplies the fifth digit and the medial half of the forth digit on the volar and dorsal surface.