The transverse head of adductor hallucis arises from the lesser MTP joint capsules and the deep transverse metatarsal ligament, forming the horizontal muscular component that bridges the metatarsal heads. It works with the oblique head to adduct the hallux and is the primary dynamic transverse arch stabiliser.
| Origin | Plantar MTP joint capsules of the 3rd, 4th, and 5th toes and deep transverse metatarsal ligament |
|---|---|
| Insertion | Lateral base of the proximal phalanx of the hallux and lateral sesamoid (with the oblique head) |
| Nerve Supply | Lateral plantar nerve (deep branch) |
| Blood Supply | Plantar metatarsal arteries |
| Actions | Adducts the hallux toward the second toe; Maintains the transverse arch of the foot |
|---|
The transverse head of adductor hallucis is a key pathological structure in hallux valgus deformity, where it contracts and rotates the sesamoids, contributing to the progressive lateral displacement of the hallux. Surgical correction of hallux valgus includes lateral soft tissue release with transverse head tenotomy or recession. Its contracted state is visible on axial MRI as a tight band between the lateral sesamoid and the 3rd-5th MTP capsules.
Not reliably palpable in isolation due to its plantar depth, but its tightness is assessed clinically by passive hallux adduction testing.
Fibrotic shortening of the transverse head contributing to progressive hallux valgus deformity, requiring surgical release during bunion correction to restore sesamoid position and hallux alignment.
