232 POSTERIOR FEMORAL REGION. 



when the adductor magnus muscle will be exposed in its entire 

 extent. 



The Adductor magnus is a broad triangular muscle, forming a 

 septum of division between the muscles situated on the anterior and 

 those on the posterior aspect of the thigh. It arises by fleshy fibres 

 from the ram us and side of the tuberosity of the ischium ; and radiat- 

 ing in its passage outwards is inserted into the whole length of the 

 linea aspera, and inner condyle of the femur. The adductor magnus 

 is pierced by five openings : the three superior, for the three perfo- 

 rating arteries ; and the fourth, for the termination of the profunda. 

 The fifth is the large oval opening in the tendinous portion of the 

 muscle, that gives passage to the femoral vessels. 



Relations. By its anterior surface with the pectineus, adductor 

 brevis, adductor longus, femoral artery and vein, profunda artery 

 and vein, with their branches, and with the posterior branches of 

 the obturator vessels and nerve. By its posterior surface with the 

 semi-tendinosus, semi-membranosus, biceps, and gluteus maximus. 

 By its inner border with the gracilis and sartorius. By its upper 

 border with the obturator externus, and quadratus femoris. 



The Gracilis (slender) is situated along the inner border of the 

 thigh. It arises by a broad but very thin tendon, from the edge of 

 the ramus of the os pubis and ischium ; and is inserted by a rounded 

 tendon int the inner tuberesity of th tibia, feeatatk the expansion 

 of the sarterius. 



B.dtitie'a.s.JLj it* inner r snperfifitl surface with the faseia lata, 

 aid hl*w with tht sartoriii and internal saphegen nerve ; the in- 

 ternal saphenous vein crosses it lying superficially to the fascia lata. 

 By its outer or deep surface with the adductor longus, brevis, and 

 magnus, and the internal lateral ligament of the knee-joint, from 

 which it is separated by a synovial bursa common to the tendons of 

 the gracilis and semi-tendinosus. 



Actions. The iliacus, psoas, pectineus, arid adductor longus 

 muscles bend the thigh upon the pelvis, and, at the same time, from 

 the obliquity of their insertion into the lesser trochanter and linea 

 aspera, rotate the entire limb outwards ; the pectineus and adductors 

 adduct the thigh powerfully ; and, from the manner of their insertion 

 into the linea aspera, they assist in rotating the limb outwards. The 

 gracilis is likewise an adductor of the thigh ; but contributes also 

 to the flexion of the leg, by its attachment to the inner tuberosity of 

 the tibia. 



Posterior femoral Region. 



Biceps, 



Semi-tendinosus, 



Semi-membranosus. 



Dissection. Remove the integument and fascia on the posterior 

 part of the thigh by two flaps, as on the anterior region, and turn 

 aside the gluteus maximus from the upper part ; the muscles may 

 then be examined. 



