37 Anatomy Applied to Medicine and Surgery. 



nal saphenous vein is situated in the superficial fascia and 

 lies internal to the nerve, above, but runs behind it, about 

 two inches above the external malleolus. 



The Muscles of this region are : The Gastrocnemius, 

 which arises by two heads one, from the upper and back 

 part of the internal condyle, and the other from the upper 

 and back part of the external condyle. These heads unite 

 at the upper part of the middle third of the leg and then 

 terminate in an aponeurosis, which, receiving the soleus, 

 becomes the tendo Achilles. Its actions will be consider- 

 ed with those of the soleus. Soleus. From the back of 

 the head of the fibula, from the upper third of the posterior 

 surface of fibula, from the oblique line of the tibia,, and the 

 middle third of its internal border and from the fascia be- 

 tween these heads ; into an aponeurosis which unites with 

 that of the gastrocnemius. Tendo Achilles. This ten- 

 don, nearly six inches in length, commences a little be- 

 low the middle of the leg and is about five-eighths of an 

 inch in width and three-eighths of an inch in thickness. It 

 is narrowest about one and a half inches above its inser- 

 tion into the lower part of the posterior surface of the os 

 calcis. A bursa is interposed between the tendon and the 

 upper part of this surface, so that, in case of any swelling 

 occurring in this situation, it is advisable to bear in mind 

 the existence of this synovial sac. Actions of these com- 

 bined muscles. They extend the foot, so that, when they 

 contract, in the erect position of the body, they act 

 as the power, the body being the weight, and the con- 

 tact of the anterior parts of the metatarsal bones with the 

 ground, the fulcrum. These muscles are brought in- 

 to action in such movements as walking, leaping, jumping, 

 etc., and, when acting from below, they support the body 

 the soleus steadying the tibia on the astragalus, and the 

 gastrocnemius, the femur on the tibia. After they have 



