538 



THE MUSCLES AND FASCIA. 



fragments depending upon the degree of laceration of the ligamentous structures around 

 the bone. 



In oblique fracture of the shaft of the tibia (Fig. 342), if the 'fracture has taken place 

 obliquely from above, downward and forward, the fragments ride over one another, the lower 



fragments being drawn backward and upward 

 by the powerful action of the muscles of the 

 calf; the pointed extremity of the upper 

 fragment projects forward immediately be- 

 neath the integument, often protruding 

 through it and rendering the fracture a 

 compound one. If the direction of the 

 fracture is the reverse of that shown in the 

 figure, the pointed extremity of the lower 

 fragment projects forward, riding upon the 

 lower end of the upper one. By bending the 

 knee, which relaxes the opposing muscles, 

 and making extension from the ankle and 

 counter-extension at the knee, the fragments 

 may be brought into apposition. It is often 

 necessary, however, in compound fracture, to 

 remove a portion of the projecting bone with 

 the saw before complete adaptation can be 

 effected. 



Fracture of the fibula with dislocation 

 of the foot outward (Fig. 343), commonly 

 known as "Pott's Fracture," is one of the 

 most frequent injuries of the ankle-joint. 

 FIG. 341. Fracture The end of the tibia is displaced from the 

 of the patella. corresponding surface of the astragalus ; the 



internal lateral ligament is ruptured ; and 



the inner malleolus projects inward beneath the integument, which is tightly stretched over 



it and in danger of bursting. The fibula is broken, usually 

 from two to three inches above the ankle, and occasionally 

 that portion of the tibia with which it is more directly 

 connected below ; the foot is everted by the action of 

 the Peroneus longus, its inner border resting upon the 

 ground, and at the same time the heel is drawn up by 

 the muscles of the calf. This injury may be at once 

 reduced by flexing the leg at right angles with the thigh, 

 which relaxes all the opposing muscles, and by making 

 extension from the ankle and counter-extension at the knee. 



FIG. 340. Fracture of the 

 femur above the condyles. 



FIG. 342. Oblique fracture of 

 the shaft of the tibia. 



FIG. 343. Fracture of the fibula with dislocation of the 

 foot outward " Pott's Fracture." 



