5 44 APPLIED ANATOMY. 



point of greatest bending is sometimes low down toward the ankles or close up to 

 the knee-joint, or the whole diaphysis of the bones may be curved. They are often 

 curved anteroposteriorly as well as laterally (Fig. 556). 



When the point of greatest bending is close to the knee-joint it has been called 

 genu varum, but the condyles remain of equal length and the epiphyseal line still 

 remains parallel with the joint line. 



As knock-knees and bow-legs so commonly occur in the actively growing period, 

 from the second to the fifth year, apparatus is often of benefit, but frequently forcible 

 straightening by means of an osteoclast or by the hand or epiphysiolysis (see page 

 542) or osteotomy is resorted to for their correction. 



Osteotomy. In osteotomy of the femur the bone is to be divided, as advised 

 by Macewen, a finger-breadth, at least, above the adductor tubercle and 1.25 cm. 

 (^ in.) in front of the adductor magnus tendon. In knock-knee many surgeons 



prefer dividing the bone from the outside of 

 the limb instead of the inside as advised by 

 Macewen. This incision avoids the epiphyseal 

 line, which is opposite the adductor tubercle, 

 and also the anastomotica magna and superior 

 articular arteries. The popliteal vessels are 

 also to be avoided by knowing their position 

 and not directing the osteotome toward them. 

 In performing osteotomy of the bones of the 

 leg the tibia is to be divided by the aid of 

 the chisel, and the fibula is to be broken by 

 manual force. Wedge-shaped resections of 

 bone are commonly not to be advised. They 

 are difficult to do, liable to complications, and, 

 under the most favorable circumstances, are 

 very long in healing and do not give any better 

 results than simple osteotomy or osteoclasis. 

 Ligation of the Popliteal Artery. 

 In the middle of its course the popliteal artery 

 lies deep between the condyles of the femur 

 and on the posterior capsule and gives oft" 

 the articular arteries. For these reasons liga- 

 tion in this part of its course is not performed. 

 To ligate it in the upper part of its course an 

 incision is to be made along the outer edge 

 of the semimembranosus muscle near the 

 middle of the upper part of the popliteal space. 

 The muscle being drawn inward the internal 

 popliteal nerve is first seen and drawn outward, 

 then the vein beneath is also drawn outward and the artery found beneath and a 

 little to the inner side. Don't mistake the semitendinosus for the semimembranosus. 

 The former is a round tendon, the latter is muscular. Another method consists 

 in making the incision immediately behind the adductor magnus tendon. The 

 semimembranosus and semitendinosus are then to be drawn backward and the artery 

 located by its pulsation and the aneurism needle passed from within out. The nerve 

 and vein, being more to the outer side, are not disturbed (Fig. 557). 



To ligate the popliteal artery in its lower third, make an incision in the midline 

 between the heads of the gastrocnemius muscle, avoiding the short saphenous vein 

 and nerve. Open the deep fascia, draw the internal popliteal nerve to the inner side, 

 the popliteal vein to the outer side, and pass the needle from without in. Flexing 

 the knee will relax the gastrocnemius and enable the artery to be more readily 

 exposed. 



Amputation through the Knee-joint. Disarticulation at the knee-joint is 

 usually done either with a long anterior and short posterior or two lateral flaps. 

 This amputation differs from others in the fact that a large rounded mass of bone 

 the condyles with no muscles is to be covered by the flap. Therefore the flaps 



FIG. 556. Bow-legs. 



