Muscular compartment
Contains peroneus longus & brevis + superficial peroneal nerve which supplies them; bounded by anterior & posterior intermuscular septa.
- blood from branches of peroneal artery which pierce FHL and post septum
- veins ¨ mostly small saphenous.
Arises: head and upper 2/3 of fibula & intermuscular septum¨ tendon passes to sole
Inserts: base of 1st MT + medial cuneiform cf tibialis anterior
Arises: lower 2/3 of fibula
- tendon lies behind (grooving) lateral malleolus
- tendon of longus lies on it, not contacting the malleolus
- pass together to peroneal trochlea of lateral calcaneus
Inserts: brevis passes above the trochlea ¨ tubercle at base of 5th MT
- cf peroneus longus passes below lying against cuboid, with a sesamoid to its insertion.
Tendons of these muscles bound down by superior & inferior peroneal retinacula.
- superior at back of malleolus to calcaneus
- inferior at peroneal trochlea ¨ upper slip to extensor retinaculum
Share a common synovial sheath, from above lat malleolus, splits at peroneal trochlea
Nerve: Superficial peroneal (L5,S1)
Action: Evert, weakly plantarflex; longus also helps maintain longitudinal arch.
Test: foot everted, tendons palpated below lateral malleolus.
Begins in longus at division of common peroneal
Passes behind longus, emerges behind anterior intermuscular septum
¨ medial and lateral branches to foot.