Proximal phalanx of big toe: anatomy, location and function

What it is

The proximal of the two phalanges of the big toe (hallux).

Location

Articulates with the first metatarsal at the first metatarsophalangeal joint and with the distal phalanx.

Function

Bears much of the force at push-off during walking and running.

Body system

Skeletal · paired (left and right)

FMA ID

FMA43253 (Foundational Model of Anatomy)

Key facts

• The big toe has only two phalanges, proximal and distal.
• Abductor hallucis and the medial head of flexor hallucis brevis insert on the medial side of its base; adductor hallucis and the lateral head of flexor hallucis brevis on the lateral side.
• Extensor hallucis brevis inserts on its dorsal base.

Clinical relevance

Hallux valgus (bunion) involves lateral deviation of the big toe at this joint.

The nearest named structures in the 3D model, measured from the centre of each part:

• Proximal phalanx of second toe · skeletal
• Distal phalanx of big toe · skeletal
• Sesamoid bone of foot · skeletal
• Middle phalanx of second toe · skeletal
• Proximal phalanx of third toe · skeletal
• Transverse head of adductor hallucis · muscular
• Middle phalanx of third toe · skeletal
• Distal phalanx of second toe · skeletal
• First metatarsal bone · skeletal
• First plantar interosseous of foot · muscular