Flexor Hallucis Longus Tendon, Plantar View

Description

Plantar exposure of the male foot centers on the flexor hallucis longus tendon as it courses from the posterior leg into the sole, passing deep to the medial malleolus and then running inferior to the talus on the sustentaculum tali (the talar shelf). Distal to the talus, the tendon continues anteriorly along the plantar surface of the calcaneus and midfoot, crossing deep to the flexor digitorum longus at the so-called knot of Henry before tracking toward the first metatarsal and hallux phalanges. Adjacent structures you would expect in this perspective include the plantar fascia, quadratus plantae, lumbricals, the long plantar ligament region, and the first metatarsophalangeal complex with its sesamoids beneath the head of the first metatarsal. Clean landmarks. Following the FHL under the sustentaculum tali matters because that fibro-osseous tunnel is a frequent site of stenosing tenosynovitis and attritional split tears, classically in dancers and runners with posteromedial ankle pain and triggering of the hallux. Surgeons also use this relationship during hindfoot and subtalar approaches, where the sustentaculum tali and adjacent neurovascular bundle define safe planes and help avoid iatrogenic injury when working near the tarsal tunnel. Seeing the tendon’s plantar course clarifies why hallux flexion can reproduce symptoms behind the ankle and why pathology may present distal in the medial arch. Use this artwork in lower-limb gross anatomy teaching to connect leg compartment anatomy to the plantar foot, or in podiatry and orthopaedic foot and ankle materials discussing FHL tendinopathy, tenolysis, tendon transfer, and plantar approach landmarks. It also suits radiology education when correlating MR and ultrasound findings at the retromalleolar groove, sustentaculum tali, and knot of Henry. Anatomical accuracy verified by SciePro's Medical Advisory Board.