Case report of a new variant of double incomplete superficial palmar arch.

A rare, unique and previously non-described form of duplicated incomplete superficial palmar arch is reported in the right hand of a male cadaver. The two incomplete arches were formed from the continuation of two terminal palmar branches of the ulnar artery in the distal third of forearm that were connected by a small transverse artery superficial to the flexor retinaculum. Both arches had no contribution from the radial artery. The palmar digital branches from the lateral arch supplied the lateral two-and-a-half fingers, while those from the medial arch supplied the medial two-and-a-half fingers. The thumb and index had additional blood supply from the princeps pollicis and radialis indicis branches of radial artery. The deep palmar arch was entirely formed by the radial artery with no contribution from the ulnar artery. Previous reports on various patterns of superficial palmar arch are highlighted, and the anatomical and clinical importance of the new pattern are discussed.