170 SPECIAL ANATOMY. 



336. Tendinous sheaths of the flexors on the fingers ; they 

 consist of separate ligaments, as : 



1. Transverse ligaments, annuli, narrow, passing before each 

 joint transversely in front of the tendons, attached to the basis 

 phalang. and the pulley. 



2. Ligamentous sheaths ; broader, transverse before the bodies 

 of the first and second phalanx. 



3. Crucial ligaments, ligg. cruciata, before the first and second 

 phalanx, descending obliquely from the edges of the body to the 

 capitulum of the phalanx. 



VIII. Muscles of the Inferior Extremity. 

 A. Muscles of the Thigh. 



337. 1. Flexor Femoris. 



a. Psoas Magnus (Internal Head). 



Figure : at commencement flat, then round and spindle-shaped. 

 Pos. : on the sides of the bodies of the lumbar vertebrae, between 

 the external and central crura of the diaphragm, before plex. lum- 

 balis, quadratus lumborum, behind the kidneys, then on the 

 boundary between the great and small pelvis, covered by perito- 

 naeum ; on the outer side nerv. cruralis passes. Behind it meets 

 with quadratus lumborum. Or. : first to the fifth lumbar verte- 

 brae (lateral surface of bodies). Ins. : Trochanter minor. The 

 tendon passes in front of the hip-joint (with a synovial capsule). 



338. b. Iliacus (External Head). 



Fig. : broad, three-sided. Pos. : fills up the whole venter Ilii. 

 covered by a fascia, fat and peritonaeum. Passes out from the 

 pelvis, united with psoas, in a groove between spina ilei anter. 

 infer, and eminent, pectin., underneath lig. Poupart. Upon it, 

 to the right, are placed the caecum and the termination of the 

 small intestines ; to the left, the colon. Or.: Fossa Iliaca and 

 lig. ileo-lumbale. Ins. : Trochanter minor. 



On the thigh they lie, both united together, behind n. cruralis 

 (in one sheath), internal to Sartorius and rectusfemoris, external 

 to the adductores and art. cruralis. Use : to elevate (flex) the 

 thigh towards the trunk, or to bend the trunk forwards over the 

 thigh. 



Nerves : cruralis and plexus lumbalis. 



339. 2. Psoas Minor (often wanting). 



Pos. : on the internal border and before the lumbar portion of 

 the former muscle, the tendon on the inner edge of fascia iliaca, 

 crossing the Psoas major. Or. : bodies of last dorsal and first 



