FOSSA POPLITEA 235 



1. Superficial fascia. 



2. The small saphenous vein. 



3. The posterior cutaneous nerve of the thigh. 



4. Popliteal fascia. 



I Biceps femoris. 

 Semitendinosus. 

 Semimembranosus. 

 Gastrocnemius. 

 Plantaris. 



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



7. The popliteal artery and vein and their branches. 



8. A few lymph glands. 



9. A slender branch from the obturator nerve. 

 10. The popliteus muscle. 



Surface Anatomy. The space which lies immediately 

 behind the knee-joint, and between the hamstring muscles 

 and the two heads of the gastrocnemius, is termed the ham. 

 It is depressed when the knee is flexed, but forms a slight 

 prominence when the joint is fully extended. By flexing 

 the knee and pressing deeply into the interval between the 

 hamstrings, the (injected) popliteal artery may be distinguished, 

 and its pulsations can usually be felt in this situation in the 

 living subject. With the limb in the same position, the 

 tendon of the biceps femoris, on the lateral side of the space, 

 is distinctly seen, as it passes distally to its insertion into the 

 head of the fibula. The head of the fibula lies posterior 

 and a little distal to the most projecting part of the lateral 

 condyle of the tibia, and by pressing deeply between the 

 fibula and the lateral condyle of the femur, the cord-like 

 collateral fibular ligament can be distinguished. When the 

 knee-joint is flexed and the limb is abducted, the rounded 

 tendon of the adductor magnus may be detected on the 

 medial side. It should be traced distally to the adductor 

 tubercle. This bony projection is placed on the femur 

 at the point where the medial supracondylar ridge joins the 

 proximal and posterior part of the medial condyle, and is an 

 important landmark, inasmuch as it indicates the level or the 

 plane of junction between the distal epiphysis and the body 

 of the femur. The common peroneal nerve (O.T. external 

 popliteal) may be felt as it crosses the lateral side of the 

 neck of the fibula, just before it pierces the peronseus longus 

 muscle. In muscular subjects, on the upper part of the 

 back of the leg, the two heads of the gastrocnemius form 

 prominent objects. 



The posterior region of the thigh presents a smooth, 



