A rare case of a punched nerve syndrome of the deep motor branch of the ulnar nerve

Abstract

Peripheral compression neuropathy of the ulnar nerve is a frequent condition, most likely encountered at the ulnar sulcus or the Guyon's canal. High-resolution ultrasound (HRUS) can often identify the site of injury. Primarily idiopathic, compression neuropathy can stem from a punched nerve syndrome, in which direct contact between an arterial branch and the nerve leads to compression. A 42-year-old male patient was examined by means of HRUS using a 17-5MHz linear transducer on a Philips iU22(®) (Philips, Bothell, Washington, USA). After reporting a punched nerve syndrome of the deep motor branch of the ulnar nerve distal to the Guyon's canal, the patient underwent surgery and showed electrophysiological and clinical improvement 6months after decompression. HRUS is a viable method to demonstrate a punched nerve syndrome. In conjunction with clinical presentation, even unlikely sites of compression such as the deep motor branch of the ulnar nerve can be identified.