830 



HUMAN ANATOMY. 



{bb) The second or middle perforating artery (a. perforans secunda) arises a little below the 

 first and, after piercing the adductor brevis and the adductor magnus, divides into an ascending 

 and a descending branch which anastomose respectively with the descending branch of the first 

 and the ascending branch of the third perforating. A nutrient artery to the femur is usually 

 given off from this vessel, although frequently it comes from the third perforating. 



{^cc) The third or inferior perforating artery (a, perforans tertia) arises usually on a level 

 with the lower border of the adductor brevis. It pierces the adductor magnus and terminates, 

 like the other perforating arteries, by dividing into an ascending and a descending branch. The 

 ascending branch anastomoses with the descendmg branch of the second perforating, while the 

 descending one anastomoses with branches from the terminal portion of the profunda. The 

 nutrient artery to the femur is frequently given off by this branch. 



Variations. — The variations of the profunda and its branches are somewhat numerous, and 

 to a very considerable extent are largely associated with one another. In other words, there 

 may be more or less dissociation of the various vessels of the profunda complex, one or other 

 of them having an independent origin from the femoral, and, indeed, this process may occur to 

 such an extent that a profunda femoris as a definite vessel can hardly be said to exist. 



The point of origin of the profunda from the femoral is stated to be usually about 4 cm. 

 distant from Poupart's ligament, but the figure must be taken as a general average from which 

 there may be wide departures. Thus, in 430 limbs Quain found that the distance from Poupart's 

 ligament of the origin of the profunda was between 2.5 and 5.1 cm. in 68 per cent., and of 

 this number it was between 2.5 and 38 cm. in 42.6 per cent. It was distant less than 2.5 cm. in 

 24.6 per cent, of the limbs and more than 5.1 cm. in only 7.4 per cent. Quain's figures are as 

 follows : 



Origin at Poupart's ligament 7 cases. 



0-1.3 cm. below Poupart's ligament 13 cases. 



1.3-2.5 cm. below Poupart's ligament • . . 86 cases. 



2.5-3.8 cm. below Poupart's ligament . 1S3 cases. 



3.8-5. 1 cm. below Poupart's ligament 109 cases. 



5.1-6.3 cm. below Poupart's ligament 1^9 cases. 



6.3-7.6 cm. below Poupart's ligament 12 cases. 



II. 6 cm. below Poupart's ligament i case. 



Essentially similar results have been obtained by Srb and other observers, and it seems 

 evident from the statistics that the origin of the profunda is more apt to be above than below the 

 point taken as the average. 



One or other of the circumflex arteries may arise independently from the femoral, this con- 

 dition occurring somewhat more frequently in the case of the internal circumflex than in that of 



the outer one, and the point of origin of the inde- 

 FiG. 734. pendent vessel may be either above or below that 



of the profunda. When it is the internal circum- 

 flex which is the independent vessel, its origin is 

 most frequently above that of the profunda; or per- 

 haps it would be more correct to say that with an 

 independent internal circumflex the origin of the 

 profunda is apt to be some\\hat below the typical 

 point. With a high origin of the profunda, the 

 external circumflex may be represented by two 

 vessels, one of which arises from the profunda, 

 while the accessory one springs from the femoral 

 lower down. Occasionally both circumflexes may 

 arise independently from the femoral, the profunda 

 in such cases having usually a low origin, and one 

 or other of the perforating arteries may arise from 

 the circumflexes. An extreme case of this nature, 

 representing an almost complete dissociation of the 

 profunda, h"as been described by Ruge, ( Fig. 734) 

 in which the superior perforating arises from the 

 internal circumflex and the middle one .from the 

 external circumflex, what may be termed the pro- 

 funda arising 9.7 cm. below Poupart's ligament 

 and giving ofi^ only the inferior perforating. 



The internal circumflex may be very much 

 reduced in size or even absent, its territory being- 

 supplied by branches from the obturator artery. Occasionally, although rarely, one or other 

 of the perforating branches arises directly from the femoral, and a similar origin has also been 

 observed for the descending branch of the external circumflex. ' 



6. The Muscular Branches. — The muscular branches (rami musculares) of 

 the femoral artery are rather numerous and are distributed to all the muscles upon the 

 front of the thigh. They are variable in number and position and do not call for any 

 special description. 



Superficial 



circumflex iliac- 



External 



circumflex 



Middle 



perforating' 



Inferior perforating 

 (profunaa femoris) 



Superficial 

 epigastric 



Internal 

 circumflex 



Superior 

 perforating 



Diagram showing almost complete dissociation 

 of profunda femoris. {Ruge). 



