260 SURGICAL ANATOMY OF 



sac of which had suppurated, or between an abscess and 

 ruptured popliteal artery, forming a diffuse aneurism, 

 difficulty might be expected ; but here the condition of 

 the pulse below will generally determine the case. 



SURGICAL ANATOMY OF THE KNEE-JOINT. 



The articulations of the knee-joint are three in num- 

 ber viz., between the femur and the patella, between 

 the femur and the tibia, and between the tibia and the 

 head of the fibula. The structure of the bones entering 

 into the formation of the joint is the same in each in- 

 stance, cancellated tissue, inclosed in a layer of compact 

 tissue. The articular extremities of the bones are well 

 supplied with bloodvessels, these enter the patella on its 

 anterior, and the femur on its posterior surface. 



The articular surface of the patella is divided verti- 

 cally by a crest into two facets, the rounder of which 

 corresponds with the outer, and .the longer and flatter 

 with the inner articular portion of the trochlea. 



The lower articular end of the femur is convex in 

 front and concave posteriorly, and the internal condyle 

 is lower than, and a little posterior to, the external, pre- 

 senting on its inner side the inner tuberosity for the at- 

 tachment of the internal lateral ligament, and a well- 

 marked tubercle, very plainly felt beneath the integu- 

 ment, for the attachment of the tendon of the adductor 

 magnus. The tuberosity of the outer condyle is less 

 prominent than that of the inner, and gives attachment 

 to the external lateral ligament. The articular surface 

 extends higher on the outer side than on the inner, and 

 is moreover in advance of it and broader. During com- 

 plete flexion only, the patella occupies the centre of the 



