484 The Popliteal Space 



tibial and dorsalis pedis arteries. Coldness and gangrene quickly 

 supervene, and amputation above the knee has to be resorted to. 



The most certain method of treatment consists in ligation of the 

 femoral artery at the apex of Scarpa's triangle ; compression of the 

 common femoral and forcible flexion of the knee sometimes prove 

 successful. But, when an aneurysm is large and its walls are likely to 

 yield, the femoral must be tied at once. 



Popliteal abscess may begin in one of the lymphatic glands, or 

 in the connective tissue of the space, and the pus may eventually find 

 its way into the joint, or amongst the muscles of the back of the thigh 

 or leg. The strength of the fascia lata delays its spontaneous escape 

 to the surface of the limb. 



The abscess should be evacuated by incising the skin, super- 

 ficial and deep fasciae, in the groove between the ilio-tibial band and 

 the bicipital tendon, the director and dressing-forceps being used for 

 the deep part of the exploration. The lower end of the femur and the 

 depths of the space are readily accessible in this way, and without 

 risk of damaging important structures. The track being made in 

 front of the external popliteal nerve, all that the surgeon has to guard 

 against wounding is the superior external articular artery. 



Sinuses left after the evacuation of an abscess may refuse to heal 

 unless the limb is kept in absolute rest in a splint ; and it may be well 

 to have the knee gently flexed. 



In amputation at the knee-joint the long anterior flap, being 

 but poorly supplied with blood, is apt to slough. The mass of 

 condyles needs a very large flap. This flap is made by an incision 

 extending from one tuberosity of the femur down over the tubercle of 

 the tibia, and up to the other femoral tuberosity. The joint is opened 

 through the ligamentum patellae ; the lateral and crucial ligaments 

 are divided, and the knife is passed through to the back of the joint, 

 and, cutting downwards and backwards, severs the popliteus, the pop- 

 liteal vessels and nerves, the hamstring tendons, gastrocnemius, and 

 plantaris. As it descends behind the tibia and fibula, it detaches a 

 short posterior flap. 



carden did a sort of 'Syme' (p. 499) at the joint, shaping the 

 ordinary oval, anterior flap, removing the patella, and cutting straight 

 back, making no posterior flap ; he removed the condyles just as Syme 

 sliced off the malleoli in the case of amputation at the ankle. 



Gritti's is on the principle of a ' Pirogoff ' (500) ; it is much like 

 Garden's, but instead of the patella being removed, a slice is taken 

 from its articular cartilage, and the denuded surface is then turned 

 under the sawn end of the femur. 



An excellent amputation at the knee is by lateral flaps, the scar 

 being eventually drawn up out of the vay of pressure, behind and 

 between the -xmdyles. 



In the case of malignant disease in the leg it is safer to amputate 



