The supercial palmar arch is an anastomosis formed mainly by the
Ulnar artery with variable contribution from branches of radial Artery.
It passes medial to the hook of the hamate, then curves laterally to form
an arch that is convex distally and level with a transverse line through
the distal border of the fully extended pollicies base. About a third of
the supercial palmar arches are formed by the ulnar artery alone; a
further third are completed by the supercial palmar branch of the
radial artery; and a third by the arteria radialis indicis, a branch of either
arteria princeps pollicis or the median artery. The supercial palmar
arch is covered by palmaris brevis and the palmar aponeurosis and it is
supercial to exor digiti minimi, branches of the median nerve and
the long exor tendons and lumbricals.