THE POPLITEAL ARTERY 



697 



anastomosing with the anastomotica magna and inferior internal articular; the 

 other ramifies close to the surface of the femur, supplying it and the knee-joint, 

 and anastomosing with the superior external articular artery. This branch is 

 frequently of small size, a condition which is associated with an increase in the 

 size of the anastomotica magna. The external branch (a. genu superior lateralis) 

 passes above the outer condyle, beneath the tendon of the Biceps, and divides into 

 a superficial and deep branch; the superficial branch supplies the Vastus externus, 

 and anastomoses with the descending branch of the external circumflex and the 

 inferior external articular arteries; the deep branch supplies the lower part of 

 the femur and knee-joint, and forms an anastomotic arch across the bone with 

 the anastomotica magna and the inferior internal articular arteries. 



The azygos articular (a. genu media) is a small branch arising from the pop- 

 liteal artery opposite the bend of the knee-joint. It pierces tfcie posterior ligament, 

 and supplies the ligaments and synovial membrane in the interior of the articu- 

 lation. 



Descending branch of 

 external circumflex. 



Superior external 

 articular. 



Inferior external 

 articular. 



Superior fibular. 



Anterior recurrent 

 tibial. 



Anastomotica 

 magna 



Deep branch of anas- 

 tomotica magna. 

 Superficial branch of 

 anastomotico magna. 



Superior internal 

 articular. 



Inferior internal 

 articular. 



FIG. 484. Circumpatellar anastomosis. 



The inferior articular arteries, two in number, arise from the popliteal be- 

 neath the Gastrocnemius, and wind around the head of the tibia below the joint. 

 The internal branch (a. genu inferior medialis) first descends along the upper mar- 

 gin of the Popliteus muscle, to which it gives branches; it then passes below the 

 inner tuberosity, beneath the internal lateral ligament, at the anterior border of 

 \yhich it ascends to the front and inner side of the joint, to supply the head of the 

 tibia and the articulation of the knee, anastomosing with the inferior external 

 articular and superior internal articular arteries. The external branch (a. genu 

 inferior lateralis) passes outward above the head of the fibula, to the front of the 

 knee-joint, passing in its course beneath the outer head of the Gastrocnemius, the 



