Ultrasound in diagnosis of anatomical variation of anterior and posterior tibial arteries.

AIMS Knowledge about branching pattern of the popliteal artery is very important in any clinical settings involving the anterior and posterior tibial arteries. This study aims to elucidate the anatomical variation patterns and common types of anterior tibial artery (ATA) and posterior tibial arteries (PTA) in the general population in China. MATERIAL AND METHODS Anatomical variations of ATA, PTA, and peroneal artery were evaluated with ultrasound in a total of 942 lower extremity arteries in 471 patients. RESULTS Three patterns of course in the PTA were ultrasonographically identified: 1) PTA1: normal anatomy with posterior tibial artery entering tarsal tunnel to perfuse the foot (91.5%), 2) PTA2: tibial artery agenetic, and replaced by communicating branches of peroneal artery entering tarsal tunnel above the medial malleolus to perfuse the foot (5.9%), and 3) PTA3: hypoplastic or aplastic posterior tibial artery communicating above the medial malleolus with thick branches of peroneal artery to form a common trunk entering into the tarsal tunnel (2.4%). In cases where ATA was hypoplastic or aplastic, thick branches of the peroneal artery replaced the anterior tibial artery to give rise to dorsalis pedis artery, with a total incidence of 3.2 % in patients, and were observed more commonly in females than in males. Hypoplastic or aplastic termini of ATA and PTA, with perfusion of the foot solely by the peroneal artery, was identified in 1 case. In another case, both communicating branches of the peroneal artery and PTA entered the tarsal tunnel to form lateral and medial plantar arteries. CONCLUSIONS Anatomical variation of ATA and PTA is relatively common in the normal population. Caution should be exercised with these variations when preparing a peroneal artery vascular pedicle flap grafting. Ultrasound evaluation provides accurate and reliable information on the variations.