International Journal of Health Sciences & Research (www.ijhsr.org) 437 Vol.6; Issue: 2; February 2016 International Journal of Health Sciences and Research www.ijhsr.org ISSN: 2249-9571 Case Report Rapidly Progressive Ulnar Neuropathy in the Guyon’s Canal by a Ganglion Cyst Mayur M Kamani 1* , Dileep K.S 2** , Arjun Ballal 3# , Y. Nishanth Shetty 4** , Anoop Hegde 1# 1 Consultant, 2 Assistant Professor, 3 Registrar, 4 Post Graduate, Department of Orthopaedic Surgery, * AARNA Superspecialty Hospital, Mani Nagar, Ahmedabad-380008, Gujarat. ** K. S. Hegde Medical Academy, Deralakatte, Mangalore-575018. # ARS Hospital, 6/53, 6 th Street, Thennampalyam Extension, Palladam Road, Tirupur-641604, Tamil Nadu. Corresponding Author: Arjun Ballal Received: 06/01/2016 Revised: 27/01/2016 Accepted: 27/01/2016 ABSTRACT Ulnar nerve neuropathy can occur due to a variety of causes. Compression at the Guyon’s canal is also an important cause. Fractures of the hook of hamate, repeated trauma, ulnar artery aneurysm are some of the major causes which cause ulnar nerve compressive neuropathy at the Guyon’s canal. The case report we present here is of a 51 year old lady who presented to us with a sudden loss of hand grip and sensory disturbances of the palm for two months. The clinical examination was suggestive of a progressive ulnar neuropathy. Radiological evaluation was suggestive of a ganglion cyst arising from the wrist compressing the ulnar nerve in the Guyon’s canal. Early decompression and excision of the ganglion with post-operative rehabilitation led to full recovery of symptoms and improvement of grip strength and motor power. Keywords: Ulnar nerve, neuropathy, interossei, palmaris brevis, hypothenar muscles, claw hand. INTRODUCTION Repetitive trauma, swellings, tumors etc are major causes for ulnar nerve compression in the Guyon’s canal. [1] A ganglion cyst causing compressive neuropathy of the ulnar nerve at the Guyon’s canal is extremely rare, [1] Rapid onset of motor deficits and sensory deficits can occur depending on the location of the ganglion cyst at the Guyon’s canal. [2] Early diagnosis and surgical intervention and rehabilitation can bring about recovery of the symptoms. [2] In this report we present a lady who developed partial claw hand with sensory deficits of her dominant hand caused by ulnar nerve neuropathy caused by the ganglion cyst. CASE REPORT A 51-year-old housewife presented with rapidly progressive weakness and paraesthesia in fourth and fifth digits of her dominant right hand with clawing of 4 th and 5 th fingers for two months. There was no history of any trauma or neck symptoms. On examination, she had weakness of interossei and hypothenar muscles (MRC grade 3) and sensory