VENOUS PUMPS OF THE HAND - THEIR CLINICAL IMPORTANCE

Oedema remains one of the most common causes of hand stiffness. Local venous return is intimately associated with oedema formation and manag ement. To elucidate the underlying mechanisms of venous return, the ve nous pumping systems in the hand were objectively and quantitatively i nvestigated using Doppler ultrasound, cadaveric dissection and venogra phy. It was demonstrated that functionally there are three independent venous systems: the superficial palmar, deep palmar and dorsal veins, which are activated by palm compression, isometric intrinsic muscle c ontraction, and dorsum compression, respectively. Each system was inve stigated independently and found to increase venous blood velocity in both the cephalic and ulnar veins. These systems were also shown to ac t in synergy, producing the greatest velocity increase when concurrent ly activated during fist-clenching. The volume of blood pumped during fist-clenching could also be potentiated by preloading by digit abduct ion. The clinical applications of these findings are discussed.