636 DISSECTION OF THE LEG. 



The tendon of the semimembranosus muscle is inserted beneath the 

 internal lateral ligament into an impression at the back of the inner tuber- 

 osity of the head of the tibia : between it and the bone is a synovial 

 bursa. The tendon sends some fibres to the internal lateral ligament, a 

 prolongation to join the fascia on the popliteus muscle, and another to the 

 posterior ligament of the knee joint. 



The posterior ligament (ligament of Winslow), wide and membranous, 

 covers the back of the jofnt between the two lateral, and is joined by 

 fibres from the tendon of the 'semimembranosus, which are directed across 

 the joint to the outer side. It is fixed below to the head of the tibia 

 behind the articular surface, and above to the femur, but by strongest 

 fibres opposite the intercondyloid notch. Numerous apertures exist in it 

 for the passage of the vessels and nerves to the interior of the articulation ; 

 and the tendon of the popliteus pierces it. 



The anterior ligament (ligamentum patella?) (fig. 217, 2 ), part of the 

 tendon of insertion of the extensor muscle of the knee (p. 571), is two 

 inches long. Superiorly it is attached to the lower part of the patella, 

 and to the depression on the inner surface of the apex ; and inferiorly it 

 is inserted into the tubercle of the head of the tibia, and into an inch of 

 the bone below it. An expansion of the triceps extensor covers it; and 

 a bursa intervenes between it and the top of the tubercle of the tibia. 



Dissection (fig. 218). To see the reflections of the synovial membrane 

 raise the knee on blocks, and open the joint by an incision on each side, 



ig. 218. 



THE CAPSULE OF THE KNEE-JOINT CUT ACROSS, AND THE PATELLA THROWN DOWN TO SHOW THE 

 NAMED FOLDS OF THE SYNOVIAL SAC. 



a. Mucous ligament. b. Internal, and c, external alar ligament. 



above the patella. When the anterior part of the capsule with the patella 

 is thrown down, a fold (mucous ligament) will be seen extending from the 

 intercondyloid fossa of the femur to a mass of fat below the patella. On 

 each side of the knee-pan is a similar fold (alar ligament) over some fat. 

 The limb may be laid flat on the table, and some of the posterior liga- 



