The adductor hallucis has two heads: the oblique head arises from the bases of the second, third, and fourth metatarsals and the fibrous sheath of the peroneus longus tendon, while the transverse head arises from the plantar ligaments of the third, fourth, and fifth MTP joints. Both heads converge on a single tendon that inserts on the lateral sesamoid of the first MTP joint and the lateral base of the proximal phalanx of the hallux, alongside the lateral head of the flexor hallucis brevis.
The adductor hallucis tendon is the primary deforming force in hallux valgus, pulling the proximal phalanx and sesamoid complex laterally as the first ray pronates and the metatarsal head migrates medially. During hallux valgus surgery, lateral soft tissue release includes division of the adductor hallucis tendon at its insertion, the lateral sesamoid suspensory ligament, and the lateral joint capsule to correct the deformity. Failure to release this tendon adequately leads to persistent valgus deformity and a high recurrence rate.
Chronic lateral pull of the adductor hallucis tendon on the proximal phalanx, combined with medial metatarsal drift, progressively displaces the toe laterally and the metatarsal head medially, forming the bunion deformity corrected surgically by lateral soft tissue release including tendon division.
Adductor hallucis contracture draws the sesamoid complex from its groove beneath the first metatarsal head, causing the tibial sesamoid to sublux laterally under the metatarsal head and contributing to sesamoid pain and first MTP joint incongruence.
