Lower limb
Extensor hallucis longus
Musculus extensor hallucis longus
- Origin
- Middle third of the anterior surface of the fibula and the interosseous membrane
- Insertion
- Dorsal side of the base of the distal phalanx of the great toe
- Function
- Extension of the great toe and support of dorsiflexion of the foot
- Innervation
- Deep fibular (peroneal) nerve, L4-L5
- Movement & chain
- Works together with tibialis anterior during the swing phase of gait to lift the foot and toes (preventing toe drag). During push-off, it acts eccentrically alongside flexion of the great toe.
- Palpation
- The tendon is clearly visible and can be followed across the dorsum of the foot, medial to the tendon of extensor digitorum longus, during active extension of the great toe.
- Clinical
- Can become entrapped under the extensor retinaculum in anterior tarsal tunnel syndrome, with sensory loss between the first and second toes.
- Segmental innervation
- L4-L5 (myotome for toe extension, clinically used when testing the L5 nerve root).
- In clinical practice
- Used in neurological examination as a bedside test for the L5 nerve root: the patient is asked to extend the great toe against resistance.
- Region in the model
- Lower limb