THE MUSCULAR SYSTEM 



77 



outward. Nerve-supply, anterior branches of the second 

 and third lumbar. 



The psoas parvus is a long, slender muscle, situated in 

 front of the psoas magnus. It arises from the last thoracic 

 and the first lumbar vertebrae. In- 

 sertion, iliac fascia and iliopectineal 

 eminence. Action, makes the iliac 

 fascia tense. Nerve, anterior branch 

 of first lumbar. 



The iliacus is a flat, radiated 

 muscle that fills up the whole of 

 the iliac fossa (internal), from 

 which point, as well as from the 

 inner margin of the iliac crest and 

 sacrum, it originates. Inserted, 

 with the tendon of the psoas mag- 

 nus, into the lesser trochanter of 

 the femur. Action, same as the 

 psoas magnus. Nerve, anterior 

 crural. 



The muscles of the anterior 

 femoral region are: 



FIG. 39. Superficial 

 muscles ot hip and thigh 

 (from behind) : i, Gluteus 

 medius ; 2, gluteus maxi- 

 mus ; 3, vastus externus ; 

 4, biceps flexor cruris ; 5, 

 semitendinosus ; 6, semi- 

 membranosus ; 7, gra- 

 cilis ; 8, sartorius ; 9, ad- 

 ductor magnus ; 10, n, 

 gastroOnemius; 12, origin 

 of plantaris. 



Tensor vaginae femoris. 



Sartorius. 



Rectus femoris. 



Vastus externus. 



Vastus internus. 



Crureus. 



Subcrureus. 



The tensor vaginae femoris is a short, flat muscle, situ- 

 ated at the upper and outer side of the thigh. Origin, 

 outer part of the crest of the ilium and anterior superior 

 spinous process. Inserted in the fascia lata at the outer 

 side of the thigh. Action, internal rotator of the thigh. 

 Nerve, superior gluteal. 



