Princeps pollicis artery arising from the superficial palmar arch.

We present a 48-year-old male cadaver in which the right superficial palmar arterial arch had no contribution from the radial artery and terminated by giving rise to a common trunk for the princeps pollicis and radialis indicis arteries. The dorsal radial artery of the thumb was absent and no arterial supply was provided by the radial artery. Accordingly, the entire arterial supply to the right thumb was provided by the superficial palmar arterial arch, which was composed solely of the ulnar artery, which received no collateral supply from the radial artery system. Considering that the arterial supply of the thumb in the present case was solely provided by the superficial palmar arch, a potential hazard could exist in the event of traumatic injury to the ulnar artery.