480 THE INFERIOR EXTREMITY 



downward displacement of the head of the talus, which may 

 sometimes form a visible prominence, but it is correspondingly 

 diminished in talipes varus (p. 495). The prominent ridge on 

 the base of the first metatarsal can be felt at a point i J inches in 

 front of the navicular tuberosity. 



The first metatarso-phalangeal joint lies a little in front of the 

 centre of the ball of the great toe, while the others are placed 

 one inch behind the web of the toes. 



FIG. 142. Normal Ankle-joint of Child, aged fourteen. Antero-posterior 

 view. Observe the levels of the epiphyseal lines of the tibia and fibula. 



The level of the ankle-joint can be made out when the foot is 

 passively flexed and extended alternately, as the anterior border 

 of the distal extremity of the tibia is easily felt. When the foot 

 is extended, the anterior part of the upper surface of the body 

 of the talus projects beyond the tibia and can be examined 

 immediately distal to it. The head of the talus can be felt three- 

 quarters of an inch above and behind the navicular tuberosity. 



In effusions into the ankle-joint the extensor tendons are 

 elevated by the distended capsule, and the depressions on each 

 side of the tendo calcaneus (Achillis) become occluded. 



