108 



SURGERY. 



second circular incision. Tiien a catlin is to be passed between the 

 bones, so as to divide the interosseous ligament and muscles ; a 

 three-tailed retractor is then to be applied, and the bones sawn 

 through together. If the spine of the tibia projects much, it can be 

 removed by a fine saw, or bone-nippers. The vessels are to be 

 secured, and the stump treated as in amputation of the thigh, the 

 integuments being brought together in a straight line. 



Flap Operation. — This is generally preferred, and is thus per- 

 formed. The surgeon first places the heel of the knife on the side 



Fig. 39. 



of the limb, farthest from him, and draws it across the front of the 

 limb, in a semicircular direction, making a semilunar flap. When 

 its point has arrived at the opposite side, it is at once made to trans- 

 fix the limb, and then the larger and posterior flap is cut. Tn trans- 

 fixing the limb, care must be taken not to pass the knife between 

 the bones. This amputation may also be performed near the ankle ; 

 but, in this instance, it will be necessary to shorten the tendo Achil- 

 iis after the flap is made. The leg should not be amputated nearer 

 the knee than the tuberosity of the tibia, or the joint will be opened, 

 and inflammation result. Hence amputation at the kfiee is rarely 

 performed, although disarticulation may be readily performed with 

 a large scalpel. In this operation the patella should be allowed to 

 remain. 



AMPUTATION OF THE FOOT. 



The foot is amputated at two places. 



Choparlh Operation. — A flap is made from the upper part of the 

 instep, and the disarticulation commenced immediately behind the 

 tuberosity of the scaphoid bone. The bistoury is passed between 

 the scaphoid and head of the astragalus, and then between the cu- 



