161 



DISSECTION OF THE THIGH. 



Obturator 

 nerve 



is divided 

 into two. 



The super- 

 ficial part 



ends on 

 femoral 

 artery, and 

 joins plexus 

 in the thigh; 



branches are 

 to hip-joint, 



muscular to 

 adductors. 



Deep part of 

 the nerve 



ends in 



adductor 



magnus 



and gives 

 branch to 

 knee-joint. 



Dissect 

 profunda. 



Profunda 

 artery : 



origin, 

 course, 



and ending ; 



parts 

 around. 



The OBTURATOR NERVE (fig. 62, 1 ) is derived from portions of the 

 second, third, and fourth lumbar nerves, and supplies the adductor 

 muscles of the thigh, as well as the hip and knee-joints. The 

 nerve issues from the pelvis through the aperture in the upper 

 part of the thyroid foramen ; and it divides in that opening into 

 two parts, which are named superficial and deep, from their 

 position with respect to the adductor brevis muscle. 



A. The superficial part ( 2 ) of the nerve is directed over the 

 adductor brevis, but beneath the pectineus and theadductorlongus, 

 to the femoral artery, on which it is distributed : at the lower 

 border of the last muscle it furnishes an offset or two, joining 

 in a plexus with the internal cutaneous and saphenous nerves 

 (p. 141), and of ten helping to supply the integuments.* 



In the aperture of exit, this piece of the nerve sends outwards an 

 articular twig to the hip-joint. 



Muscular branches from this superficial part are furnished to the 

 pectineus (sometimes), adductors longus and brevis, and the gracilis. 



B. The deep part ( 4 ) of the obturator nerve pierces the fibres of 

 the external obturator muscle, and, continuing beneath the 

 adductor brevis, is consumed chiefly in the adductor magnus. The 

 following offsets are supplied by it : 



. Muscular branches enter the obturator externus as the nerve 

 pierces it ; others are furnished to the large, and sometimes to the 

 short adductor. 



A slender articular branch (fig. 62, 5 ) enters the fibres of the 

 adductor magnus, and passes through this near the linea aspera to 

 reach the popliteal artery, by which it has been seen that it is 

 conducted to the back of the knee-joint. 



Dissection. To prepare the profunda artery and its branches, 

 as far as they are to be seen on the front of the thigh, it will 

 be requisite to follow back the internal circumflex artery above 

 the upper border of the adductor brevis, and to trace the per- 

 forating branches to the apertures in the adductors near the 

 femur. 



The DEEP FEMORAL (fig. 62, c) is the chief muscular artery of 

 the thigh, and arises from the common femoral about an inch and 

 a half below Poupart's ligament. At its origin the vessel is placed 

 on the outer side of the parent trunk ; but it is soon directed 

 inwards beneath the superficial femoral vessels to the inner side of 

 the femur, and ends at the lower third of the thigh in a small 

 branch that pierces the adductor magnus. 



In Scarpa's triangle the vessel lies at first on the iliacus muscle. 

 On the inner side of the femur it is parallel to the superficial 

 femoral artery, though deeper in position ; and it is placed first 

 over the pectineus and adductor brevis, and thence to its termination 

 between the adductus longus and magnus. 



* In some bodies the superficial part of the nerve is of large size and has a 

 distribution similar to that of the inner branch of the internal cutaneous nerve, 

 the place of which it takes : in such instances it joins freely in the plexus. 



