Posterior tibial artery It is the direct continuation of the popliteal artery, supply the muscles of the back and it is the main artery of the foot begin at the lower border of the popliteus m. then descend with the tibial nerve and two venae commitants deep to the gastrocnemius, soleus and the transverse intermuscular septum of the leg. it runs first laterally and after it gives the peroneal artery it inclines medially then passes behind the medial malleolus. It ends by dividing into medial and lateral planter arteries deep to flexor retinaculum.

Branches in the leg: 1-peroneal artery it is the largest branch. it gives: a-muscular branches to the muscles of the lateral compartment of the leg. b-Nutrient branch to the fibula. c-Perforating artery. d- lateral calcaneal and posterior lateral malleolar.

Posterior tibial artery

2- circumflex fibular artery runs around the neck of the fibula supply skin and muscles. 3-Nutrient artery to the tibia. 4-Muscular branches to the deep muscles of the back of the leg. 5-Communicating branch with the peroneal artery behind the ankle joint. 6-Medial calcanean artery. 7-Posterior medial malleolar to the posterior part of the medial malleolus.

Posterior tibial artery

Synovial sheaths of the extensor tendons There are 3 separate synovial sheaths: 1- Surrounding the tendon of the tibialis anterior m. 2- Surrounding the extensor hallucis longus m. 3- Surrounding the tendon of the extensor digitorum longus and peroneus tertius.

Synovial sheaths

Extensor expansions It is similar to that of the fingers formed from the tendons of the extensor digitorum longus muscle, each tendon divided into 3 parts at the metatarsophalangeal joint. The thick central part inserted in the base of the middle phalanx. The lateral and medial parts of the expansion continue distally inserted in the base of the distal phalanx. The tendons of the lumbrical muscles join the medial side of the expansion in each toe.

Synovial sheath of the flexor tendons Each tendon deep to the flexor retinaculum is separated from others by tendenous sheath and each is surrounded by its own synovial sheath, this sheath begin approximately 2cm above the tip of the medial malleolus, that of the flexor digitorum longus extend to the middle of the foot, that of the tibialis posterior m. extend to its insertion while that of the flexor hallucis longus m. extends either to the middle of the foot or to the insertion.

Sole of the foot The skin of the sole is thickened over the heel and the heads of the metatarsal bones while it is thin on the toes. Superficial fascia it is dense especially over the heel and the ball of the foot and contain fats.

Cutaneous nerves of the sole 1- medial calcaneal branches from the tibial nerve distributed to the heel and the posterior part of the of the sole. 2- lateral calceneal branches from the sural nerve. 3- planter cutaneous branches from the lateral and medial planter nerves. 4- Planter digital nerves.

Deep fascia (planter fascia) it is continuous with the fascia of the dorsum of the foot, it is extremely thick in the intermediate region forming the planter aponeurosis but it is thin medially and laterally where it covers the abductors of the big and little toe. The thinner medial planter fascia covers the intrinsic muscles of the great toe. The lateral planter fascia is thick near the heel and thin toward the little toe covers the intrinsic muscles of the little toe.

Planter aponeurosis it consists of longitudinally arranged bands of white fibrous connective tissues which diverge toward the toes from the medial process of the tuberosity of the calcaneus. it is triangular in shape occupy the central part of the sole. Anteriorly it widens and split into 5 slips near the heads of the metatarsal bones, each slip pass to one toe bound to the proximal phalanx.

compartments of the sole The sole divided into 3 compartments: A great toe compartment located medially under the medial planter fascia. A little toe compartment located laterally under the lateral planter fascia. The central compartment located deep to the planter aponeurosis bounded by the lateral and medial intermuscular septa. The interosseous adductor compartment lies deep to the central compartment

The great toe compartment This compartment contains the abductor hallucis and flexor hallucis brevis muscles, the medial planter nerve and vessels, and the first metatarsal bone.

The medial planter nerve It is the larger of the two terminal branches of the tibial nerve. It arise deep to the posterior part of the abductor hallucis and passes forward accompanied by the small medial planter artery It gives: 1-muscular branches to the abductor hallucis and flexor digitorum brevis muscles. 2- articular branches supply the joint and tarsal and metatarsal bones. 3- planter cutaneous branches supply the skin of the medial part of the sole.

The medial planter nerve become cutaneous at the middle of the sole divided into proper digital branch to the medial side of the great toe which supply the flexor hallucis brevis muscle. Three common digital branches supply the medial three and half toes. The first common digital branch supply the first lumbrical muscle.

Planter nerves

The medial planter artery The smaller branch of the posterior tibial artery, it does not form an arch it accompanied the medial planter nerve and lies first under the abductor hallucis and then between it and the flexor digitorum brevis muscle, supplying these muscles.

It gives small branches to the skin, the muscles and the joints, the artery divided into three digital branches which anastomosed with the three planter metatarsal arteries of the planter arch at the base of the first three interdigital cleft