Arch Hand Microsurg.  2020 Mar;25(1):71-75. 10.12790/ahm.19.0046.

Compression Neuropathy of the Ulnar Nerve due to the Accessory Abductor Digiti Minimi at Guyon’s Canal: A Case Report

• Lee J
• Kim JK
• Whang JI

• KMID: 2501115
• DOI: http://doi.org/10.12790/ahm.19.0046

Abstract

Guyon’s canal syndrome is a compression neuropathy of the ulnar nerve that occurs at the wrist. Compression can be caused by many conditions, such as benign tumors, repeated occupational trauma, vascular lesions, fractures of the carpal bones, rheumatoid arthritis and anomalous hypothenar muscle at Guyon's canal. Here, the authors report a case of compression neuropathy of the ulnar nerve by the accessory abductor digiti minimi muscle (AADM), one of the anomalous hypothenar muscles, at Guyon's canal. The case report is accompanied by a literature review.

Keyword

Guyon’s canal; Ulnar nerve; Accessory abductor digiti minimi muscle

Figure

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  Fig. 1. T1-weighted transverse magnetic resonance images at the level of the pisiform bone. (A) Relationship between the accessory abductor digiti minimi muscle (AADM), ulnar nerve (UN), and ulnar artery (UA). (B) AADM located volar to the UN. (C) AADM fused with abductor digiti minimi muscle (ADM). P, pisiform.

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  Fig. 2. Intraoperative photo. (A) The accessory abductor digiti minimi muscle (AADM) muscle with an oblique course at Guyon's canal. (B) After proximal part of the AADM was cut. A branch of ulnar nerve (UN) can be seen innervating the AADM. (C) Complete resection of the AADM.

Reference

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