2. The Leg It is the portion between the knee and the ankle. It is comprised of two long bones (tibia –medially and fibula -laterally).
3. The Leg The leg is divided into four compartments Anterior compartment Lateral compartment (Superficial) Posterior compartment Deep posterior compartment
4.
5.
6.
7. Anterior Compartment Anterior compartment contains the muscles that dorsiflex the ankle and extend the toes. Contains Anterior Tibial Nerve Contains Anterior Tibial Artery.
11. Anterior Compartment Tibialis anterior (TA) Origin -lateral condyle of tibia, upper half/lateral surface of tibia, interosseous membrane Insertion - medial cuneiform, base of 1st metatarsal Nerve - deep fibular (peroneal) (L4-5) Action - ankle dorsiflexion, forefoot inversion
12. Anterior Compartment Extensor DigitorumLongus (EDL) Origin - lateral condyle of tibia, ant surface of fibula, interosseous membrane Insertion - dorsum of base of middle phalanx, dorsum of base of distal phalanx Nerve - deep fibular (peroneal) (L5-S1) Action - extension of toes, dorsiflexion of ankle
13. Anterior Compartment Extensor HallucisLongus (EHL) Origin - middle ½ of ant fibula, IM Insertion - distal phalanx of the great toe Nerve - deep fibular (peroneal) (L5-S1) Action - extend the great toe, dorsiflex ankle
14. Anterior Compartment Fibularis (Peroneus) Tertius Origin - distal 1/3 ant fibula, interosseous membrane Insertion - dorsum shaft of 5th metatarsal Nerve - deep fibular (peroneal) (L5-S1) Action - forefoot eversion, weak ankle dorsiflexion
15. Lateral Compartment Lateral compartment contains the muscles that Everters of the foot (turns foot outward) Contains the superficial peroneal nerve
16. Lateral Compartment Blood supply: No major arteries in lateral compartment. Muscular branches arise from the peroneal artery (Branch of posterior tibial). Nerve supply: Superficial peroneal (fibular) nerve
18. Lateral Compartment Fibularis (Peroneus) Longus (FL) Origin - head, upper 2/3 lateral surface of fibula Its tendon courses behind lateral malleolus, underneath the fibular trochlea, and lies in the groove in the cuboid bone before going to its place of insertion Insertion - inferolateral surface of medial cuneiform , 1st metatarsal on its inferior surface Nerve - superficial fibular (peroneal) (L5-S1) Action - forefoot eversion, ankle plantar flexion
19. Lateral Compartment Fibularis (Peroneus) Brevis (FB) Origin - lower 2/3 lateral fibula Courses behind lateral malleolus and underneath the fibular trochlea Insertion - tuberosity on base of 5th metatarsal Nerve - superficial fibular (peroneal) (L5-S1) Action - forefoot eversion, ankle plantar flexion
20. (Superficial) Posterior compartment Posterior compartment contains the plantar flexors muscles. Contains: Short saphenous vein Peroneal communicating branch of the common peroneal nerve Medial cutaneous nerve of the calf Sural nerve
28. Deep Posterior Compartment Popliteus Origin - lateral condyle of femur and lateral meniscus Insertion – proximal shaft of tibia Nerve -Tibial nerve Action – flex and medially rotate leg
29. Deep Posterior Compartment Flexor digitorumlongus Origin - shaft of tibia Insertion - distal phalanges of toe 2-5 Nerve -Tibial nerve Action – plantarflex and invert foot, flex toe
30. Deep Posterior Compartment Flexor hallucislongus Origin - shaft of fibula Insertion - base of distal phalanx of big toe. Nerve -Tibial nerve Action - plantarflex and invert foot, flex toe
31. Deep Posterior Compartment Tibialis posterior Origin – shafts of tibia and fibula & interosseous membrane Insertion - Major tendon insertion passes to tuberosity of navicular. Posterior tendon slips pass to calcaneus, plantar surface of all 3 cuneforms, cuboid and to base of 2nd, 3rd, and 4th metatarsals. -- Nerve -Tibial nerve Action - plantarflex and invert foot