152 MUSCULAR SYSTEM. 



CRUREUS VEL CRURALIS. 



(Middle Division of Uie 'rri-J'emoro-roluleus.) 



Situation. — Deep-seated in the hollow formed by the rectus 

 above, the vasti on either side, and the femoral bone below. 



Form. — Fusiform ; elongated. 



Attachment. — Antero-superiorly, to the ileum, just above the 

 acetabulum ; postero-inferiorly, to the body of the femoral bone 

 and to the patella. 



Relations.— yf'ith. the muscles and bone to which it lies con- 

 tiguous. 



Structure. — Tendinous at its extremities; intermediate parts, 

 fleshy ; under part, aponeurotic. 



Action of the two Vasti and the Crureus, considered as a 

 Triceps or one entire Muscle. 

 In consequence of their connexion, through the intervention of 

 the patella and its ligaments, with the tibia, these muscles be- 

 come direct extensors of the thigh ; and their power as such is 

 considerably enhanced by the peculiar construction of the stifle- 

 joint, which enables them to act with the combined mechanical 

 advantages of pulley and lever. In progression, they raise the 

 thigh and advance it forwards under the body ; and in that po- 

 sition, as soon as the limb has become a fixed point, they will 

 assist in progressing the haunch. 



INTERNAL ILIO-FEMORAL REGION, 

 Comprehends the muscles forming the prominent rotundity of 

 the inner part of the haunch. 



SARTORius. — Sub-lumho-tibialis. 



Situation. — Antero-internal part of the haunch. 



Form. — Long, slender, pyramidal ; anterior part broadest. 



Attachment. — Antero-superiorly, to the bodies of the posterior 

 lumbar vertebrae, and to the brim of the pelvis midway between 

 the symphysis pubis and the anterior spinous process of the ileum ; 

 inferiorly, to the supero-internal part of the tibia, and to the in- 

 ternal condyle of the femoral bone. 



Relations.— On the outer side, with the psoas magnus, vastus 

 internus and gracilis ; on the inner, with the faschia lata and 

 skin. Along its posterior and outer border run branches of the 

 femoral bloodvessels. 



Structure.— Vleshy and rather pale ; except the extremities, 

 which are aponeurotic. Its anterior aponeurotic end is so in- 



