BRANCHES OF THE PROFUXDA. 439 



reach the back part of the thigh, where they anastomose with the internal circumflex 

 and the perforating branches of the deep femoral, and with the gluteal and sciatic 

 branches of the internal iliac. 



(b) Ascending branches, directed upwards beneath the sartorius and rectus, and 

 afterwards under the tensor muscle of the fascia lata, communicate with the terminal 

 branches of the gluteal, and with some of the external descending branches of the 

 circumflex iliac artery. 



(c) Descending branches incline outwards and downwards upon the extensor 

 muscles of the knee, covered by the rectus muscle. They are usually three or four in 

 number, some being of considerable size ; most of them are distributed to the muscles 

 on the fore part of the thigh, but one or two can be traced beneath the vastus externu.s 

 muscle as far as the knee, where they anastomose with the arterial branches sur- 

 rounding that joint. 



2. The internal circumflex artery, smaller than the external circumflex, 

 arises close to that branch from the inner and hinder part of the deep 

 femoral aitery, and is directed backwards between the pectineus and the 

 psoas muscles to the inner side of the femur, so that only a small part of it 

 can be seen without displacing these muscles. On reaching the tendon of 

 the external obturator, along which the vessel passes to the back of the 

 thigh, it divides into two principal branches. 



(a) The anterior branch is distributed partly to the adductor brevis and gracilis, 

 and partly to the external obturator muscle, near which it anastomoses with the 

 obturator artery. 



(b) The posterior branch passes backwards above the small trochanter, and 

 appears on the back of the limb, between the quadratus femoris and great adductor 

 muscles, where it supplies the hamstring muscles, and anastomoses with the sciatic 

 artery and with the superior perforating branches of the deep femoral artery. 



An articular vessel, arising from the posterior branch opposite the hip joint, enters 

 the joint through the notch in the acetabulum, beneath the transverse ligament, and 

 supplies the adipose tissue and the synovial membrane in that articulation. Some 

 offsets are guided to the head of the femur by the round ligament. In some instances 

 the articular branch is derived from the obturator artery ; and sometimes the joint 

 receives a branch from both sources. 



3. The perforating arteries (perforantes) are branches which reach the 

 back of the thigh, by perforating the adductor brevis and adductor magnus 

 muscles ; they are four in number, including the terminal branch of the 

 parent vessel. 



(a) The first perforating artery passes backwards below the pectineus muscle, 

 through the fibres of the adductor brevis and magnus, and is distributed to both 

 these adductor muscles, to the biceps and great gluteal muscles, and communicates 

 with the sciatic and internal circumflex arteries. 



(b) The second perforating artery, considerably larger than the first, passes 

 through the adductor brevis and magnus ; after which it divides into ascending and 

 descending branches, which ramify in the hamstring muscles, and communicate with 

 the other perforating branches ; an offset from it, named the nutrient artenj of the 

 femur, enters the medullary foramen of that bone. 



(c) The third perforating artery pierces the adductor magnus muscle, below the 

 insertion of the adductor longus, and is distributed in a manner similar to the second 

 perforating artery. 



(d) The fourth perforating artery, the termination of the deep femoral artery, 

 passing backwards close to the liuea aspera, is distributed to the short head of the 

 biceps and to the other hamstring muscles, and communicates with branches of the 

 popliteal artery, and with the lower perforating arteries. 



III. MUSCULAR BRANCHES OF THE FEMORAL ARTERY. In its course along 

 the thigh, the femoral artery gives off several branches to the contiguous 



