THE THIGH. 47 



dilation through the femoral artery in an amputation, or to 

 cure an aneurysm by digital compression. 



If the Italian tourniquet be used, we should be careful to 

 adjust the counter-pad well under the tuberosity of the 

 ischium. If digital pressure be used, it is easy to command 

 the femoral by slight pressure of the thumb, provided the 

 fingers have a firm hold on the great trochanter. 



1 02. Sartorius. The sartorius is the great fleshy land- 

 mark of the thigh, as the biceps is of the arm, and the 

 sterno-cleido-mastoideus of the neck. Its direction and 

 borders may easily be traced by asking the patient to raise 

 his leg, a movement which puts the muscle in action. The 

 same action defines the boundaries of the triangle (of Scarpa) 

 formed by Poupart's ligament, the adductor longus and 

 sartorius. 



Line of femoral artery. To define the course of the 

 femoral artery, draw a line from midway between the anterior 

 superior spine of the ilium and the symphysis pubis to the 

 (spurlike) tubercle for the adductor magnus on the inner side 

 of the knee. The femoral artery lies under the upper f of 

 this line. 



The sartorius begins to cross the artery, as a rule, from 

 three to four inches below Poupart's ligament. The point 

 at which the profunda artery arises is about one and a half 

 or two inches below the ligament. Therefore the incision 

 for tying the femoral in Scarpa's triangle should commence 

 about a hand's breadth below Poupart's ligament, and be conr 

 tinued for three inches in the line of the artery. 



To command the femoral in Scarpa's triangle, the pad of 

 the tourniquet should be placed at the apex, and the direction 

 of the pressure should be, not backwards, but outwards, so 

 that the artery may be compressed against the femur. 



In the middle third of the thigh the femoral artery lies in 

 Hunter's canal, overlapped by the sartorius. About the 

 commencement of the lower third the artery leaves the canal 

 through the oval opening in the adductor magnus, and, under 

 the name of popliteal, enters the popliteal space. The line for 

 finding the artery in Hunter's canal has been already traced 



