3 2 4 THE INFERIOR EXTREMITY 



They are branches of the profunda femoris and are called 

 first, second, third, and fourth, according to the level at which 

 they appear, proximo-distally. The fourth is the terminal 

 branch of the profunda, it makes its appearance about 25 mm. 

 (one inch) proximal to the opening in the adductor magnus 

 muscle through which the popliteal artery enters the popliteal 

 fossa. The perforating arteries and their branches must 

 be thoroughly cleaned, together with the apertures in the 

 adductor magnus through which they pass. It will then be 

 seen that they do not pierce the fleshy substance of the 

 muscle, for behind each is a tendinous arch, and the arteries 

 reach the posterior region of the thigh by passing between 

 the arches and the linea aspera, to which the piers of the 

 arches are attached. 



The openings are in the same line with and are in all 

 respects analogous to the large opening in the adductor 

 magnus muscle for the popliteal artery. The result obtained 

 is the same in each case ; when the muscle contracts, the 

 vessels are protected from pressure. 



After passing the tendinous arches the perforating arteries 

 wind round the posterior border of the femur on their way 

 to the vastus lateralis muscle, in which they end, and in 

 which they anastomose with branches of the lateral femoral 

 circumflex artery. The highest perforating artery pierces the 

 insertion of the glutaeus maximus before it reaches the vastus 

 lateralis, and the lower three pierce the femoral head of the 

 biceps femoris and the lateral intermuscular septum. 



Anastomoses on the Posterior Aspect of the Thigh. In a 

 well -injected subject a chain of arterial anastomoses can be 

 traced from the gluteal region to the popliteal fossa, and 

 the present is the best time to examine it. Commencing 

 proximally, in the gluteal region, the superior gluteal artery 

 is found anastomosing with the inferior gluteal, and the 

 inferior gluteal with the terminal branches of the medial 

 femoral circumflex artery. In the posterior part of the thigh 

 the chain of anastomoses is carried distally by the medial and 

 lateral femoral circumflex arteries anastomosing with the first 

 perforating artery, and by anastomoses between the perforating 

 arteries. The chain is completed distally by anastomoses 

 between the most distal perforating arteries and the muscular 

 branches given from the popliteal artery to the hamstring 

 muscles. 



