304 THE INFERIOR EXTREMITY 



attached to the acetabular rim. Many of the fibres of the 

 posterior part of the capsule run circularly round the neck 

 of the femur. Others run parallel with the neck, at right 

 angles to the circular fibres, and in the lower part of the 

 capsule, which is covered by the obturator externus, is a 

 band of fibres, the ischio-capsular band, which runs upwards 

 and laterally parallel with the course of the obturator 

 externus. 



The reflected tendon of the rectus femoris is attached to 

 the floor of a groove situated immediately above the upper 

 part of the margin of the acetabulum, and is there embedded 

 in the superficial fibres of the capsule which must be removed, 

 to expose it, by cutting through them parallel with the 

 direction of the tendon. 



FOSSA POPLITEA (POPLITEAL SPACE). 



The popliteal fossa should be dissected, if possible, before 

 the posterior region of the thigh is disturbed, in order that 

 its contents may be examined before the medial and lateral 

 boundaries of its proximal portion are displaced from their 

 positions. During the dissection the following structures 

 will be met with : 



1. Superficial fascia. 



2. The small saphenous vein. 



3. The posterior cutaneous nerve of the thigh. 



4. Popliteal fascia. 



Biceps femoris. 



Gastrocnemius. 

 Plantaris. 



6. The tibial and common peroneal nerves and their branches. 



7. The popliteal artery and vein and their branches and tributaries. 



8. A few lymph glands. 



9. A slender branch from the obturator nerve. 

 10. The popliteus muscle. 



Surface Anatomy. The area of the popliteal fossa is 

 popularly called the ham. It is situated in the posterior 

 region of the knee, and it lies behind the distal third of the 

 femur, the knee joint, and the proximal fifth of the tibia. 

 It appears as a hollow when the knee joint is flexed, but 

 forms a slight prominence when the joint is fully extended, 



