Stortån

Stortån, known in human anatomy as the hallux, is the innermost and typically the largest toe of the foot. It plays a key role in balance and locomotion. In humans, the stortån usually consists of two phalanges (proximal and distal) and forms the first metatarsophalangeal joint with the first metatarsal.

Anatomy: The hallux has two phalanges; unlike the other toes, it has an interphalangeal joint between them. The big toe is acted on by the flexor hallucis longus and flexor hallucis brevis for flexion, and by the extensor hallucis longus and extensor hallucis brevis for extension. Abductor hallucis and adductor hallucis muscles help position it, while plantar ligaments and a plantar plate stabilize the metatarsophalangeal joint. The dorsal and plantar aspects receive blood supply from branches of the dorsal and plantar arteries, and innervation is mainly by the medial plantar nerve.

Function: The stortån provides a lever for push-off during gait, helps absorb ground reaction forces, and contributes to balance and vertical stability. Its range of motion is primarily flexion and extension at the metatarsophalangeal joint, with additional movement at the interphalangeal joint.

Clinical significance: The large toe is commonly involved in conditions such as hallux valgus (bunions), hallux rigidus (arthritis of the MTP joint leading to stiffness), and turf toe (injury to the MTP joint). Other issues include ingrown toenails, sesamoid injuries, and fractures of the distal or proximal phalanx. Variation in alignment and size can influence gait and footwear requirements.