Vascular supply of nerves in the tarsal tunnel.

The normal vascular supply of nerves in the tarsal tunnel was studied by intra-arterial injection of latex. In general, the blood supply to the tibial nerve and its branches came directly from corresponding arteries. Each nutrient artery to the tibial nerve bifurcated on the surface of the lateral plantar nerve fasciculus to create longitudinal vessels that made anastomoses with bifurcating nutrient vessels proximally and distally. This primary longitudinal system supplied intersubfascicular vessels to the medial plantar fasciculus. The last nutrient artery from the posterior tibial artery usually supplied the terminal branching point of the tibial nerve midway through the tarsal tunnel. The lateral and medial plantar nerves received most of the nutrient vessels from their corresponding arteries in shorter intervals. In 65% of cases, the lateral plantar nerve received a nutrient vessel from the medial plantar artery. Potential anatomical areas of vascular compromise in the etiology or surgical release of tarsal tunnel syndrome are discussed.