516 THE MUSCLES AND FASCIAE 



between the Vastus internus and the Adductor magnus. with both of which it is 

 usually blended. 



Relations. By its superficial surface, with the fascia lata, the Sartorius, and, near its inser- 

 tion, with the femoral artery and vein; by its deep surface, with the Adductores brevis and 

 magnus, the anterior branches of the obturator nerve, and with the profunda artery and vein 

 near its insertion; by its outer border, with the Pectineus; by its inner border, with the Gracilis. 



The Pectineus and Adductor longus should now be divided near their origin, and turned 

 downward, when the Adductor brevis and Obturator externus will be exposed. 



The Adductor brevis (ra. adductor brevis} (Fig. 385) is situated immediately 

 behind the two preceding muscles. It is somewhat triangular in form, and arises 

 by a narrow origin from the outer surface of the body and descending ramus of 

 the os pubis. between the Gracilis and Obturator externus. Its fibres passing 

 backward, outward, and downward, are inserted, by an aponeurosis, into the 

 lower part of the line leading from the lesser trochanter to the linea aspera. and 

 the upper part of the same line, immediately behind the Pectineus and upper 

 part of the Adductor longus. 



Relations. By its superficial surface, with the Pectineus, Adductor longus, profunda fem- 

 oris artery, and anterior branches of the obturator nerve; by its deep surface, with the Adductor 

 magnus and posterior branch of the obturator nerve; by its outer border, with the internal cir- 

 cumflex artery, the Obturator externus, and conjoined tendon of the Psoas and Iliacus; by its 

 inner border, with the Gracilis and Adductor magnus. This muscle is pierced, near its insertion, 

 by the second or by the first and second perforating branches of the profunda femoris artery. 



The Adductor brevis should now be cut away near its origin, and turned outward, when the 

 entire extent of the Adductor magnus will be exposed. 



The Adductor magnus (ra. adductor magnus} (Fig. 385) is a large, triangular 

 muscle forming a septum between the muscles on the inner and those on the back 

 of the thigh. It arises from a small part of the descending ramus of the os pubis. 

 from the ramus of the ischium. and from the outer margin of the inferior part of 

 the tnberosity of the ischium. Those fibres which arise from the ramus of the 

 os pubis are very short, horizontal in direction, and are inserted into the rough 

 line leading from the great trochanter to the linea aspera. internal to the Glutens 

 maximus. They are considered by some a distinct muscle and called the Adductor 

 minimus. The fibres taking origin from the ramus of the ischium are directed 

 downward and outward with different degrees of obliquity, to be inserted, by means 

 of a broad aponeurosis, into the linea aspera and the upper part of its internal 

 prolongation below. The internal portion of the muscle, consisting principally 

 of those fibres which arise from the tuberosity of the ischium, forms a thick 

 fleshy mass consisting of coarse bundles which descend almost vertically, and 

 terminate about the lower third of the thigh in a rounded tendon, which is inserted 

 into thp Adductor tubercle on the inner condvle of the femur, and is connected 

 by a fibrous expansion to the line leading upward from the tubercle to the linea 

 aspera. Between the two portions of the muscle an interval is left, tendinous 

 in front and fleshy behind, for the passage of the femoral vessels from Hunter's 

 canal into the popliteal space. The external portion of the muscle at its attachment 

 to the femur presents three or four osseoaponeurotic openings, formed by tendi- 

 nous arches attached to the bone, from which muscle fibres arise. The three 

 superior of these apertures are for the three perforating arteries, and the fourth, 

 when it exists, is for the terminal branch of the profunda. 



Relations. By its superficial surface, with the Pectineus, Adductor brevis, Adductor longus, 

 and the femoral and profunda vessels and obturator nerve; by its deep surface, with the great 

 sciatic nerve, the Gluteus maximus, Biceps femoris, Semitendinosus, and Semimembranosus. 

 By its superior or shortest border it lies parallel to the Quadratus femoris, the internal circumflex 



