Lower limb
Extensor digitorum longus
Musculus extensor digitorum longus
- Origin
- Lateral condyle of the tibia and the anterior surface of the fibula, interosseous membrane
- Insertion
- Middle phalanx and distal phalanx of the second to fifth toes, via the extensor expansion
- Function
- Extension of toes 2-5 and dorsiflexion of the ankle; important for foot clearance during the swing phase of gait
- Innervation
- Deep fibular (peroneal) nerve, L5-S1
- Movement & chain
- Works together with tibialis anterior during the swing phase to lift the foot and toes (foot clearance), preventing the toes from dragging on the ground.
- Palpation
- The muscle belly is palpable anterolaterally on the lower leg, lateral to tibialis anterior, and the tendons can be followed across the dorsum of the foot during active toe extension.
- Clinical
- Paralysis due to loss of function of the deep fibular nerve (for example in a fibular head injury) contributes to the classic steppage gait.
- Segmental innervation
- L5 (myotome), used together with extensor hallucis longus and tibialis anterior when clinically testing the L5 nerve root.
- In clinical practice
- Skin and pressure point inspection; maintain comfortable positioning and proper body mechanics during patient handling and daily care.
- Region in the model
- Lower limb