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Flexor hallucis longus




Flexor hallucis longus - posterior view
Flexor hallucis longus - posteromedial view
Flexor hallucis longus - inferior view
Flexor hallucis longus - medial view

General information

  • This section is strictly limited to anatomy, you might be looking for clinical relevant information which is found under the clinical chapters -- muscles section, click here to go to that page


  • Deep


  • Posterior surface of distal 2/3 of fibula
  • Membrana interosseus
  • Intermuscular septum and fascia


  • Base and plantar side of distal phalanx at metatarsal 1

Main function

  • IP-joint
    • Flexion

Secondary function

  • Ankle
    • Plantarflexion
  • Tarsal-joint
    • Inversion
  • MCP-joint
    • Flexion

Nerve innervation

  • Segmental
    • L5-S2
  • Peripheral
    • Tibial nerve

Arterial supply

  • Posterior part of tibial artery

Palpation of distal tendon

  • Patient position
    • Supine
  • Place your hand just posteriorly to the medial malleol
  • There are 3 tendons running down posteriorly to the medial malleol:
    • Tibialis posterior
    • Flexor digitorum longus
    • Flexor hallucis longus
  • Ask the patient to flex the big toe while you feel for the contraction in the tendon of flexor hallucis longus

Strength test

  • Patient position
    • Supine
  • Staiblize the patient's foot by holding around the metatarsal bones while the foot is held in a neutral position
  • Give resistance towards the plantar side of the distal phalanx of the big toe in an extension direction, so that the patient is giving force towards flexion