216 THE INFERIOR EXTREMITY 



articulates at the ankle with a bone of the foot called the 

 talus. Unlike the tibia, the fibula is deeply situated in the 

 greater part of its length, but its proximal end, the head of 

 the fibula, is easily felt immediately below the posterior part 

 of the lateral condyle of the tibia; its distal end, which is 

 called the lateral malleolus, is also superficial, and forms a 

 prominent visible projection on the lateral side of the ankle. 

 The fibula takes no part in the formation of the knee joint, for 

 its proximal end reaches only to the lateral condyle of the tibia 

 with which it articulates. Its distal end articulates with the 

 lateral surface of the distal end of the tibia and with the 

 lateral surface of the talus ; it enters therefore into the 

 formation of the ankle joint (Figs. 101, 102, 103). 



The region below the ankle joint is the foot. In it are 

 seven tarsal bones, five metatarsal bones, and fourteen phalanges. 

 The tarsal bones form the skeleton of the posterior half of 

 the foot ; the metatarsal bones are situated in the anterior 

 half of the foot ; they are numbered one to five from the 

 medial to the lateral side. The phalanges are in the toes ; 

 two in the great toe, and three in each of the other toes. 



Each of the tarsal bones is named. The highest of the 

 group, the talus, takes part in the formation of the ankle 

 joint, where it lies directly below the tibia, wedged between 

 the malleoli of the tibia and the fibula. It articulates 

 therefore with both the bones of the leg. Its anterior part, 

 the head, can be felt below the tibia and in front of the lateral 

 malleolus. The inferior surface of the talus rests upon the 

 calcaneus, which projects backwards, behind the malleoli, to 

 form the prominence of the heel. The strong tendon which 

 descends in the back of the leg to the prominence of the 

 heel is the tendo calcaneus. In front of the talus, in the 

 medial part of the foot, is the os naviculare. Its tuberosity, 

 which is an important landmark, can be felt about 25 mm. 

 (one incJi) in front of the tip of the medial malleolus (Fig. 103). 



In front of the navicular lie the three cuneiform bones, 

 first, second, and third from the medial to the lateral side. 

 The first can be felt in front of the tuberosity of the navicular. 

 The other two can be recognised by pressure applied in the 

 dorsum of the foot, but they are not easily distinguished in 

 the undissected foot. In the lateral border of the foot, in 

 front of the calcaneus, is the last of the seven tarsal bones, 

 the cuboid. It is difficult to palpate, but immediately in front 



