The study of anatomy of tarsal tunnel in human fetuses by dissection method

Abstract

Background: The flexor retinaculum of foot extends from the medial malleolus to the calcaneus to form the roof of tarsal tunnel. The structures passing through the tunnel are tendons of tibialis posterior, flexor digitorum longus & flexor hallucis longus, the tibial nerve & the posterior tibial artery with its venae comitantes. In order to understand the pathogenesis and improve the treatment of tarsal tunnel syndrome, we investigated the tarsal region of human foetuses anatomically. Methodology: The study was done on aborted/ stillborn foetuses in the Department of Anatomy of Sapthagiri Institute of Medical, Sciences, Bangalore. The structures passing under the flexor retinaculum of foot were dissected in 68 normal limbs of 34 foetuses of gestational age ranging from 10 weeks to term. Results: It was noted that the structures were arranged in two planes. Most commonly the superficial plane contained the tendon of tibialis posterior, posterior tibial artery & tibial nerve from medial to lateral side. In the deeper plane were the tendons of flexor digitorum longus medial to that of flexor hallucis longus. The bifurcation of tibial nerve mostly occurred under cover of flexor retinaculum and that of posterior tibial artery was distal to it. Conclusion: The understanding of arrangement of structures under cover of flexor retinaculum is important for diagnosis and treatment of tarsal tunnel syndrome in adults and also for the surgical correction of clubfoot, poliomyelitis & other deformities of foot in children.