Median nerve thenar motor branch anatomical variations

Abstract

Aim. The aim of this study was to determine the prevalence of the different types of the median nerve thenar motor branch and to compare them with literature data.

Materials and Methods. This study has been conducted using median nerves dissected from cadavers stored in a 10% solution of formaldehyde at the Department of Anatomy, Jagiellonian University Medical College (JUMC) and cadavers from the Department of Forensic Medicine (JUMC). The research protocol was approved by the Jagiellonian University Ethics Committee (registry KBET/209/B/2002).

Results. The studied group comprised of 8 (26,7%) women and 22 men (age between 23-92 years), yielding a total of 60 thenar motor branches (30 right vs. 30 left). Forty-seven (78,3%) nerves were classified as extraligamentous, 12 (20%) were subligamentous and 1 (1,7%) was transligamentous. As for the side of origin of the thenar motor branch in 45 cases (75%) it was the radial side and in 2 cases (3,33%) it was the ulnar side.

Conclusions. The obtained results confirm that the extraligamentous type of the thenar motor branch is the most common and that the ulnar origin of the thenar motor branch is the rarest.