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THE MUSCULAK SYSTEM. 



THE FASCIAE AND IVIUSCLES OF THE LEG 



AND FOOT. 



FASCIJE. 



The superficial. fascia of the leg and foot presents no special features except 

 in the sole, where it is greatly thickened by pads of fat, particularly under the 

 tuberosity of the calcaneus, and under the balls of the toes. 



The deep fascia has numerous important attachments about the knee. 

 Posteriorly it forms the popliteal fascia, and is joined by expansions from the tendons 

 of the sartorius, gracilis, Semitendinosus, and biceps femoris muscles. In front of the 

 knee it is attached to the patella, the ligamentum patellse, and the tubercle of the tibia; 

 medially and laterally it is connected to the condyles of the tibia and the head of the 

 fibula, and helps to form the collateral patellar ligaments broad fascial bands which 

 pass obliquely from the sides of the patella to the condyles of the tibia, and are joined 

 by fibres of the vasti muscles. Passing into the leg, the fascia blends, over the 

 medial surface of the tibia, with the periosteum of the bone. It extends round 

 the lateral side of the leg from the anterior crest to the medial border of the tibia, 

 binding together and giving origin to the muscles, and gaining an attachment to 

 the distal part of the body of the fibula. Two septa pass from its deep surface ; 

 one septum (anterior peroneal septum), attached to the anterior crest of the fibula, 

 encloses the superficial peroneal nerve, and separates the extensor from the 

 peronaei muscles. The other septum (posterior peroneal septum) is attached to 

 the lateral crest of the fibula, and separates the peronsei from the flexor muscles. 

 From the last-named septum another extends across the back of the leg ; it forms a 

 partition between the superficial and deep flexor muscles, and encloses the posterior 

 tibial vessels and the tibial nerve. It gives rise to subordinate septa attached to 

 the vertical line of the tibia and the medial crest of the fibula, which separate 

 the tibialis posterior from the flexors of the toes on either side. 



At the ankle the deep fascia is strengthened by additional transverse fibres, 

 which give rise to thickened bands named the ligamentum laciniatum, lig. trans- 

 versurn cruris, lig. cruciaturn cruris and the retinaculum of the peroneal muscles. 

 They were formerly known as the annular ligaments. 



The ligamentum laciniatum (O.T. internal annular ligament) stretches 

 between the medial malleolus and the tuberosity of the calcaneus. While it is 

 continuous, at its proximal border, with the general investment of the deep fascia, 

 it is chiefly formed by the septal layer covering the deep muscles on the back of 

 the leg. It sometimes gives insertion to the plantaris muscle. It is continuous, 

 distally, with the plantar aponeurosis, and gives origin to the abductor hallucis 

 muscle. It is pierced by the calcanean vessels and nerve. Along with the 

 posterior tibial vessels and the tibial nerve, the tendons of the tibialis posterior, 

 flexor digitorum longus, and flexor hallucis longus, pass beneath it, each enclosed 

 in a separate mucous sheath. 



The superior peroneal retinaculum (O.T. external annular ligament) is a 

 thickened band of the deep fascia stretching between the lateral malleolus and 

 the calcaneus. It binds down the tendons of the peronsei, which occupy a space 

 beneath the ligament, lined by a single mucous sheath ; while the inferior 



