DISSECTION OF THE LOWER EXTREMITY 135 



Note especially the relation of the vein to the artery in the 

 upper and lower parts of the fossa. Incise the vein longitudinally 

 and search for valves. Are any present? 

 Lymphatics. (Vide Fig. 50.) 



(a) Popliteal lymph-nodes (lymphoglandulae popliteae). 



How many do you find? 



(b) Deep lymphatic vessels (vasa lymphatica profunda). 



Study in the floor of the fossa 



(a) Popliteal surface (planum popliteum) of the femur. 



(b) Posterior ligament (ligamentum popliteum obliquum) of the knee- 



joint. 



(c) Strong fascia covering popliteal muscle. From what muscle is this 



fascia derived? 



A careful drawing of the boundaries and contents of this 

 fossa should now be made. Each structure should be shown in 

 its proper relation and carefully labelled. To complete the study 

 make use of cross-sections. Make a drawing of a section through 

 the middle of the space, labelling each structure found and giving 

 correct relations. 



POSTERIOR SURFACE OF THIGH (FACIE S FE MORIS 



POSTERIOR). 



Make a vertical incision through the belt of skin remaining 

 in the middle of the thigh. Reflect the flaps thus formed lateral- 

 ward and medialward respectively. 



Superficial Fascia and Cutaneous Nerves. 



Note carefully branches of arteries and radicles of veins. 

 Preserve these as carefully as possible and trace back the larger 

 vessels. Study the cutaneous nerves in the superficial fascia. 

 Consult Fig. 47, p. 124. 



(a) Branches of the posterior cutaneous nerve of the thigh (N. cutaneus 



femoris posterior) (0. T. small sciatic). 



(b) On the lateral surface of the thigh, passing backward, branches 



the lateral cutaneous nerve of the thigh (N. cutaneus femon* lat- 

 eralis) (0. T. external cutaneous). 



(c) On the inner aspect of the thigh, near the knee, the cutaneous branc 



of the obturator nerve (ramus cutaneus nervi obturatoris) ; als 

 twigs from the rami cutanei anteriores nervi femoralis. 



Deep Fascia (Fascia lata). (" Broad Fascia.") 



Clean away carefully and completely the superficial fascia 

 and expose the deep layer of fascia. Note especially its 



