532 APPLIED ANATOMY. 



AMPUTATION. 



Amputation at the Hip-Joint. In amputating at the hip-joint, hemor- 

 rhage is especially to be guarded against. This comes from two sources, the femoral 

 artery anteriorly and the branches of the internal iliac posteriorly. The most reliable 

 way of controlling bleeding is probably by the use of the elastic tourniquet held in 

 place by WyeW spins. These are two steel pins 5 mm. ( T 8 F in.) in diameter and 

 25 cm. (loin. ) long. One is entered 6 mm. (^ in.) below the anterior superior 

 spine and slightly to its inner side and traverses the tissues on the outer side of 

 the hip for about 7.5 cm. (3 in.) from the point of entrance; the other is entered 

 through the skin and tendon of the adductor magnus 1.25 cm. (^ in.) below the 

 perineum and made to emerge 2.5 cm. (i in.) below the tuber ischii. The elastic 

 tube is to be wound around the hip above the pins, which prevent its slipping down 

 (Fig. 542). The amputation is then performed as desired. Compression of the 

 aorta or common iliac by instrumental means is obsolete. Sometimes the common 

 iliac is compressed laterally by the finger introduced through an incision in the 



Sartorius 



Anterior crural nerve 

 Vastus internus 



Rectus and cruret 



?M^I W "; wl^WHi 



- Gracilis 



/nifiiuiiPx 



\astus externus 



^^ Semimembranosus and 

 semitendinosus 



Biceps . Sciatic nerve 



FIG. 542. Amputation just above the middle of the' thigh, showing insertion of Wyeth's pins. 



abdominal walls. Another method consists in making lateral flaps with the femoral 

 artery in the angle of the incision all vessels are then clamped as they are divided. 



In some operations the head of the femur is disarticulated before the flaps are 

 made. In this case the first part of the operation is like a resection of the hip 

 by the Langenbeck straight incision. 



The bleeding of the posterior flap comes from branches of the gluteal, sciatic, 

 obturator, and internal pudic arteries, derived from the internal iliac. 



Amputation of the Thigh. In amputation of the thigh by the flap method 

 care must be taken to avoid splitting the femoral artery. Its position in the various 

 portions of the thigh should be borne in mind. Anteroposterior flaps are to be pre- 

 ferred to lateral ones, and a short anterior flap is to be avoided because the scar is 

 drawn posteriorly (Fig. 542). The muscles of the posterior part of the thigh, the 

 hamstrings, are not attached to the bone, with the exception of the short head of 

 the biceps, they therefore retract when cut and later pull the scar behind the bone. 

 The crureus and vastus externus and internus anteriorly are attached to the bone, 

 and hence cannot draw back either at the time of the operation or afterwards. 



