THE POPLITEAL ARTERY 279 



The Popliteal Space 



The popliteal space is lozenge-shaped, being widest at the 

 back part of the knee-joint and deepest above the articular 

 end of the femur. It is bounded externally, above the joint, by 

 the biceps, and below the joint by the plantaris and external 

 head of the gastrocnemius ; internally, above the joint, by the 

 semitendinosus, semimembranosus, gracilis, and sartorius; below 

 the joint, by the inner head of the gastrocnemius. 



Above, it is limited by the. apposition of the inner and outer 

 hamstring muscles; below, by the junction of the two heads of 

 the gastrocnemius. The floor is formed by the lower part of 

 the posterior surface of the shaft of the femur, the posterior 

 ligament of the knee-joint, the upper end of the tibia, and the 

 fascia covering the popliteus muscle, and the space is covered 

 in by the fascia lata. 



The Popliteal Artery 



The popliteal artery runs from the adductor opening to the 

 lower border of the popliteus, where it divides into the anterior 

 and posterior tibial. 



Relations. In front, femur, ligamentum posticum, popliteus; 

 behind, semimembranosus, fascia, gastrocnemius, plantaris, and 

 soleus, popliteal and short saphenous veins, and the internal 

 popliteal nerve; outer side, external condyle, outer head of the 

 gastrocnemius, plantaris, internal popliteal nerve above; inner 

 side, inner condyle, inner head of the gastrocnemius, semi- 

 membranosus, popliteal vein, and the internal popliteal nerve 

 below. 



The branches of the popliteal artery are: 



(a) Muscular superior, three or four, to the lower part of the 

 hamstring muscles to join the inferior perforating; inferior 

 (sural), to the upper part of the gastrocnemius, plantaris, and 

 soleus. 



(6) Cutaneous to the skin of the calf. 



(c) Articular superior, two in number, an external and an 

 internal, wind around above the condyles to the front. The 

 external gives a branch to the external vastus and one to the 

 joint, and also forms an arch with the anastomotica. The in- 



