244 MYOLOGY. 



Origin. From about the lower third of the anterior surface 

 of the femur. 



Insertion. To the upper surface of the patella, and the 

 capsular ligament of the joint. 



Relation. Anteriorly with the rectus ; posteriorly with the 

 femur ; laterally with the vasti. 



Action. To assist the vasti, and tense the capsular ligament. 



POSTERIOR FEMORAL REGION. 



This region contains two muscles, a large superficial one, and 

 a small one deeply situated ; they are as follows : 

 Biceps rotator tibialis. 

 Ischio-f eraoral is. 



BICEPS ROTATOR TIBIALIS. 



(Semitendinosus Ischio-tibialis Posticus.) 



(PL. II. 61 ; FIG. 84. e. e.) 



Situated behind the triceps abductor, and curved like it, with 

 the convexity behind, this muscle is long, cylindrical, and bifid 

 above, consisting of pale, fleshy fibres, divided by a strong 

 aponeurosis. 



Origin. By one head, from the spine of the sacrum, and 

 the sacro-sciatic ligament, in common with the triceps abductor ; 

 the other, which is considerably shorter, comes from the ischial 

 tuberosity. 



Insertion. To the supero-internal part and anterior crest of 

 the tibia, its aponeurosis blending with the tibial fascia and 

 the periosteum. 



Relation. Superiorly and posteriorly it is covered by the 

 gluteal fascia, and its sacral portion partly covers the triceps 

 abductor, being related with it and the sciatic nerves anteriorly ; 

 externally with the abductor magnus. 



Action. To extend the femur, flex and rotate the leg out- 

 wards, and tense the tibial fascia. 



ISCHIO-FEMORALIS. 

 (Quadratus Femoris.) 



(FiG. 83. e.) 



Situated behind the femur, between the adductor and abductor 

 muscles. This muscle consists of a flattened band, running down- 

 wards and outwards. 



