Flexor Hallucis Brevis, Plantar View

Description

Plantar anatomy of the male forefoot is rendered with the flexor hallucis brevis in the central field, positioned inferior to the first metatarsal and deep to the plantar aponeurosis. Medial and lateral heads of this intrinsic muscle course distally on either side of the tendon of flexor hallucis longus, then converge toward the base of the proximal phalanx of the hallux. Each head blends with the plantar plate at the first metatarsophalangeal joint and envelopes a sesamoid (medial tibial and lateral fibular) before inserting, leaving the flexor hallucis longus tendon to pass between them. Surrounding osseous landmarks include the phalanges of digits I to V, the metatarsals, and proximal tarsal elements, with articular cartilage indicated along the metatarsophalangeal and interphalangeal joints. Functionally, this view makes the sesamoid complex legible. The flexor hallucis brevis stabilizes the hallux against dorsiflexion at toe-off, and its relationship to the sesamoids explains both the mechanical advantage and the pain patterns seen in sesamoiditis and stress fracture in runners and dancers. The medial head commonly receives innervation from the medial plantar nerve, while the lateral head may be supplied by the lateral plantar nerve, an anatomic detail that matters when evaluating iatrogenic injury during plantar approaches to the first ray. Use this plate for teaching intrinsic plantar muscles in gross anatomy and kinesiology labs, or for pairing with clinical content on first metatarsophalangeal joint pathology such as hallux valgus, turf toe, and sesamoid disorders. It also supports surgical education on sesamoid excision planning and on endoscopic or open releases around the flexor hallucis longus tendon sheath in the plantar forefoot. Anatomical accuracy verified by SciePro's Medical Advisory Board.