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Draw a labelled diagram showing compartments of leg and their contents.
Leg is divided into three compartments.They are as follows:
- Anterior (extensor) compartment
- Lateral (posterior)compartment
- Posterior (flexor) compartment
Enumerate the muscles of anterior/extensor compartment of leg and their nerve supply.
- Tibialis anterior
- Extensor hallucis longus
- Extensor digitorum longus
- Peroneus tertius
* All the muscles of the anterior compartment of leg are supplied by deep peroneal nerve.
Write the origin, insertion and action of muscles of anterior compartment of leg.
| Muscle | Origin | Insertion | Action |
|---|---|---|---|
| Tibialis anterior | Upper 2/3 rd of lateral surface of tibia and adjoining part of interosseous membrane. | Medial side of base of 1 st metatarsal | Dorsiflexion of foot at the ankle joint. |
| Adjoining surface of medial cuneiform | Inversion of foot at subtalar and midtarsal joints. | ||
| Maintains medial longitudinal arch of foot |
| Muscle | Origin | Insertion | Action |
|---|---|---|---|
| Extensor hallucis longus | Posterior half of middle 2/4 th of the medial surface of fibula and adjacent interosseous membrane. | Base of distal phalanx of great toe. | Dorsiflexion of foot at the ankle joint. |
| Dorsiflexion of great toe. | |||
| Muscle | Origin | Insertion | Action |
|---|---|---|---|
| Extensor digitorum longus | Upper1/4 th and anterior half of middle 2/4 th of the medial surface of fibula and adjacent interosseous membrane. | Base of middle and distal phalanx of lateral four toes through extensor expansion. | Dorsiflexion of foot at the ankle joint. |
| Dorsiflexion of lateral four toes | |||
| Muscle | Origin | Insertion | Action |
|---|---|---|---|
| Peroneus tertius | Lower 1/4 th of the medial surface of fibula. | Dorsal surface of base of fifth metatarsal. | Dorsiflexion of foot at the ankle joint |
| Eversion of foot. | |||
Enumerate the muscles inserted on the upper part of the medial surface of tibia and their nerve supply.
- Sartorius – supplied by femoral nerve
- Gracilis – supplied by obturator nerve
- Semitendinosus – supplied by tibial part of sciatic nerve
Enumerate the muscles responsible for dorsiflexion and inversion of foot.
- Tibialis anterior
- Extensor hallucis longus
- Extensor digitorum longus
- Peroneus tertius
Enumerate the structures passing deep to superior extensor retinaculum from medial to lateral.
- Tibialis anterior
- Extensor hallucis longus
- Anterior tibial vessels
- Deep peroneal nerve
- Extensor digitorum longus
- Peroneus tertius
Applied Aspect
Anterior tibial compartment syndrome
Occurs following excessive exertion of the muscles of anterior compartment of leg. It could be due to soft tissue injury. Muscles within the tight compartment swell resulting in compression of anterior tibial artery and its branches, leading to ischemia and pain.