A morphometric study of the ulnar nerve in Guyon's canal

Abstract

Objectives:Guyon’s canal is clinically significant because it contains the ulnar nerve, artery and veins and is a location forcompression injury. This study was undertaken to determine the anatomy of the ulnar nerve in Guyon’s canal on 40 wristsof 20 adult formalin-fixed cadavers. Methods: 40 wrists of 20 formalin-fixed adult cadavers obtained from the Department of Anatomy, Ege University Facultyof Medicine were dissected. In each cadaver, the skin and the subcutaneous fatty tissues were removed starting from theforearm down to the palm of the hand. The palmaris brevis muscle and the palmar aponeurosis were dissected to exposeGuyon’s canal. Results: The length and diameter of the main trunk of the ulnar nerve in Guyon’s canal before dividing into its terminalbranches were measured as 11.72±1.99 mm and 3.41±0.5 mm, consequently. Within the canal, the main trunk divided intotwo terminal branches. The diameter of the deep branch was 1.77±0.47 mm and the superficial branch was 2.41±0.45 mm.The superficial branch divided into the proper palmar digital nerve supplying the medial side of the little finger and the common palmar digital nerve supplying the adjoining sides of little and ring fingers. Conclusion:An accessory abductor digiti minimi muscle was observed as a possible cause of compression in Guyon’s canal.Despite its clinical relevance, the diameters of the deep and superficial branches of the ulnar nerve in Guyon’s canal do notexist in previous studies