Interphalangeal Joints of the Foot

Description

Joints of the foot

Radiographs highlighting the interphalangeal joints of the foot

General

• Interphalangeal joints (IPJ) are the articulation between consecutive phalanges of the foot
• Each foot has 9 total (2 for each of the lateral 4, 1 for the great toe)
• Proximal interphalangeal joint: head of proximal phalanx, base of middle phalanx
• Distal interphalangeal joint: head of middle phalanx, base of distal phalanx
• Great toe: only has an interphalangeal joint between proximal and distal

Joint Description

• Classified as hinge joint
• Each IPJ completely enclosed by capsule, lined by synovial membrane
• Only permits movement in one axis: flexion and extension of the middle and distal phalanges

Articular Surfaces

• Proximal interphalangeal joints: head of proximal phalanx, base of middle phalanx
• Distal interphalangeal joints: head of middle phalanx, base of distal phalanx
• Interphalangeal joint of big toe: head of proximal phalanx, base of distal phalanx

Ligaments

• Collateral interphalangeal ligaments
• Plantar interphalangeal ligaments

Innervation

• Branches of the medial plantar nerve, lateral plantar nerve
  • Dorsal digital nerves
  • Proper plantar nerves

Vascular

• Digital branches of the plantar arch

Movements

• Flexion and extension only due to uniaxial hinge joints

Muscles acting on the interphalangeal joints

• Flexion
  • Flexor hallucis longus
  • Flexor digitorum longus
  • Flexor digitorum brevis
• Extension
  • Extensor hallucis longus
  • Extensor digitorum longus
  • Extensor digitorum brevis
  • Lumbricals of the foot
• Mixed
  • Plantar Interossei of the Foot
  • Dorsal Interossei of the Foot

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Clinical Significance

• Toe Fracture
• Toe Dislocation

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See Also

• Foot And Ankle Anatomy
• Foot Pain (Main)
• Physical Exam Foot

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