262 



THE INFERIOR EXTREMITY 



Obturator interims 

 Piriformis / 



is composed of four portions : the rectus femoris, which is 

 placed in the anterior part of the thigh, and is quite 

 distinct from the others, except at its insertion ; the vastus 

 lateralis, the vastus intermedius, and the vastus median's, 

 which clothe the body of the femur on its lateral, anterior, 

 and medial aspects, and are more or less blended with 

 each other. 



M. Rectus Femoris. The rectus femoris muscle arises by 

 two tendinous heads of origin, which were exposed when 



the dissection was 

 carried deeply in 

 the interval be- 

 tween the iliacus 

 and tensor of the 

 fascia lata (p. 250). 

 The anterior or 

 straight head springs 

 from the anterior 

 inferior spine of the 

 ilium (Fig. 116); 

 the posterior or 

 reflected head arises, 

 under cover of the 

 glutaeus minimus, from a 

 marked impression on the 

 lateral surface of the ilium, 

 immediately above the upper 

 part of the rim of the 



FIG. 117. Anterior Aspect of Proximal acetabulum (Fig. 1 1 6). It 

 Portion of Femur with Attachments , j , ., .', ,, 



of Muscles mapped out. 1S connected both with the 



capsule of the hip joint and 

 the deep lamina of the ilio-tibial tract of the fascia lata. 



At the present stage of dissection only the anterior part of the reflected 

 head is visible ; the posterior part will be seen when the gluteal region is 

 dissected. 



The two heads of origin of the rectus femoris join at a 

 right angle, immediately beyond the margin of the acetabulum, 

 and form a strong, flattened tendon, which, gives place to 

 a fusiform, fleshy belly. The tendon of origin spreads out on 

 the anterior surface of the proximal part of the muscle in the 

 form of an aponeurosis. About three inches proximal to the 

 knee joint the rectus femoris ends in a strong tendon of 



Ilio-psoas 



