An unusual branching pattern of the superficial brachial artery accompanied by an ulnar nerve with two roots

Abstract

Variations in the arterial pattern of the upper limb are common and have been reported by several investigators (Fuss et al. 1985; Poteat, 1986; Tountas & Bergman, 1993; Rodriguez-Baeza et al. 1995). These variations are often associated with anomalies in the arrangement of the nerves of the brachial plexus (Miller, 1939; Lengele & Dhem, 1989). The presence of a superficial brachial artery (Schwyzer & De Garis, 1935; Skopakoff, 1959; Fuss et al. 1985) and the usual pattern of its branching in the upper arm or forearm have also been reported (McCormack et al. 1953; Keen, 1961; Karlson & Niechalev, 1982; Lippert & Pabst, 1985; Rodriguez-Baeza et al. 1995). The great variability of this arterial pattern may be attributed to the failure of regression of some paths of the embryonic arterial trunks (Tountas & Bergman, 1993; Rodriguez-Baeza et al. 1995).

The aim of the present report is to describe the concomitant appearance of 3 unusual variations in the same upper limb of a male cadaver. In this arm: (1) a superficial brachial artery terminated its course by dividing into 3 branches at the cubital fossa; (2) the definitive brachial artery had an unusual origin; and (3) the ulnar nerve was abnormally formed from 2 roots. This novel variation is compared with other anatomical variations in the arterial supply of the upper limb. In a series of routine dissections of 100 embalmed human cadavers the following variations were observed in the right upper limb of a male subject.