Physiologic anatomy of the palmar circulation in 200 normal hands.

The functional capacity of the Superficial Palmar Arch (SPA) was evaluated in 200 normal hands by a non-invasive narrow beam ultrasonic technique. Peak systolic velocity of flow with radial artery occlusion increased in all SPAs except for 22 (11%) which were considered incomplete. Ulnar artery occlusion resulted in a more variable response including 89 (45%) SPAs with bidirectional flow. SPA blood flow is complex but understandable in terms of hand blood flow and vascular bed resistance. The use of tobacco does not increase the incidence of incomplete SPAs.