THE FEMORAL MUSCLES. 



639 



Fig. 610. 



Psoas 

 magnus 



Anterior 

 superior 

 spine of 

 ilium 



Gluteus 

 medius 



Tensor 

 fasciae 

 latae 



Pectineus 



Adductor 

 longus 



Sartorius 



Relations. — As it passes obliquely across the upper part of the thigh, the sar- 

 torius forms the lateral boundary of a triangular depression which is known as 

 Scarpa's triangle (trigonum femorale). The inner boundary of this triangle is formed 

 by the adductor longus, its base by 

 Poupart's ligament, its floor by the 

 ilio-psoas and pectineus and often to 

 a slight extent by the adductor brevis, 

 and its roof by the fascia lata and 

 the cribriform fascia. The space so 

 bounded is traversed from above down- 

 ward, from the middle of its base to 

 its apex, by the femoral vessels and 

 the anterior crural and crural branch 

 of the genito-crural nerve, and con- 

 tains a number of lymphatic nodes. 

 At its apex it is continuous with the 

 adductor or Hunter's canal. 



A mucous bursa (bursa m. sar- 

 torii propria) intervenes between the 

 tendon of the sartorius and those of 

 the gracilis and semimembranosus, 

 and occasionally communicates with 

 the bursa anserina (page 638). 



The remainder of the post-axial 

 musculature of the thigh is almost en- 

 tirely represented by four large mus- 

 cles, more or less separable above, 

 but united below in a ctpmmon tendon, 

 which is inserted into the upper bor- 

 der of the patella, and through this 

 and the ligamentum patellae acts upon 

 the tuberosity of the tibia. These 

 muscles have been grouped together 

 as the extensor quadriceps femoris, 

 and include the rectus femoris, the 

 vastus externus, the crureus, and the 

 vastus internus. 



2. Rectus Femoris (Fig. 610). 



Attachments. — The rectus fem- 

 oris has a double origin, the one, or 

 straight head, arising from the an- 

 terior inferior spine of the ilium, and 

 the other, or reflected head, from the 

 surface of the ilium a short distance 

 above the acetabulum. The two 

 heads give rise to a single tendon 

 which descends for some distance 

 along the front of the muscle and, in 

 conjunction with a median septum, 

 gives origin to the muscle-fibres. 

 These present a bipinnate arrange- 

 ment, and pass over below into the 

 common tendon to be eventually iyi- 

 serted by the ligamentum patellae into 

 the tubercle of the tibia. 



Nerve-Supply. — By the anterior crural nerve from the third and fourth lumbar 

 nerves. 



Gracilis 



Rectus 

 femoris 



Vastus internus 



Tendon of 

 extensor 

 quadriceps 



Ilio-tibia 

 band 



Tendo patellae 



Muscles of right thigh, anterior aspect. 



