POSTERIOR TIBIO-FIBULAR REGION. 



345 



POSTERIOR TIBIO-FIBULAR REGION. 



Deep Layer. 



Popliteus. Flexor Longus Digitorum. 



Flexor Longus Pollicis. Tibialis Posticus. 



Dissection. Detach the Soleus from its attachment to the fibula and tibia, and turn It 

 downwards, when the deep layer of muscles is 

 exposed, covered by the deep fascia of the leg. Fig- 193.- 



The deep fascia of the leg is a broad, 

 transverse, intermuscular septum, inter- 

 posed between the superficial and deep 

 muscles in the posterior tibio-fibular re- 

 gion. On each side it is connected to the 

 margins of the tibia and fibula. Above, 

 where it covers the Popliteus, it is thick 

 and dense, and receives an expansion from 

 the tendon of the Semi-membranosus; it 

 is thinner in the middle of the leg, but, 

 below, where it covers the tendons passing 

 behind the malleoli, it is thickened. It 

 is continued onwards in the interval 

 between the ankle and the heel, where it 

 covers the vessels, and is blended with 

 the internal annular ligament. 



This fascia should now be removed, commenc- 

 ing from below opposite the tendons, and detach- 

 ing it from the muscles in the direction of their 

 fibres. 



The Popliteus is a thin, flat, triangular 

 muscle, which forms the floor of the 

 popliteal space, and is covered by a 

 tendinous expansion, derived from the 

 Seini-membranosus muscle. It arises by 

 a strong flat tendon, about an inch in 

 length, from a deep depression on the 

 outer side of the external condyle of the 

 femur ; and from the posterior ligament of 

 the knee-joint; and is inserted into the 

 inner two-thirds of the triangular surface 

 above the oblique line on the posterior 

 surface of the shaft of the tibia, and into 

 the tendinous expansion covering the sur- 

 face of the muscle. The tendon of the 

 muscle is covered by that of the Biceps 

 and the external lateral ligament of the 

 knee-joint; it grooves the outer surface 

 of the external semilunar cartilage, and 

 is invested by the synovial membrane of 

 the knee-joint. 



Relations. By its superficial surface, 

 with the fascia above mentioned, which 

 separates . it from the Gastrocnemius, 

 Planturis, popliteal vessels, and internal 

 popliteal nerve. By its deep surface, with 

 the superior tibio-fibular articulation, and 

 back of the tibia. 



-Muscles of the Back of the Leg. 

 Deep Layers. 



4' ~ ,, 



