LIGAMENTS OF THE PELVIS. 



477 



longer and thicker than the anterior, and arises from the 

 posterior inferior spinous process of the ilium, and the 

 side of the sacrum 

 and coccyx. It is 

 inserted hy a broad 

 attachment into the 

 inner margin of the 

 tuberosity of the 

 ischium, which is 

 traced forward in 

 the shape of a falci- 

 form process, upon 

 the ramus of the is- 

 chium, and serves to 

 shield the internal 

 pudic vessels and nerves. Posteriorly, it is covered by 

 the glutens maximus muscle, to some of the fibres of which 

 it gives origin. These ligaments are of use in forming the 

 lower and lateral parietes of the true pelvis. By their 

 crossing they convert the ischiatic notches into foramina, 

 the larger and superior giving passage to the pyriform 

 muscle, the gluteal and sciatic vessels and nerves, while the 

 smaller and inferior transmit the internal pudic vessels 

 and nerve, and the tendon of the obturator internus muscle. 

 Articulation of the ossa pubis. The two ossa pubis are 

 united, along the median line, by an intermediate fibro-car- 

 tilage. Its fibres assume the form of concentric laminaa, 

 some of which are continued all round, while others are 

 interrupted ; some take the oblique course, and cross each 

 other. This articulation resembles, in some degree, the 

 intervertebral, and sometimes contains, in its centre, a 



FIG. 144 represents a posterior view of the Ligaments of the Pelvis. 1 Base 

 of sacrum. 2 Coccyx. 3 3 Crest of ilium. 4 4 Tuber ischii. 5 5 Greater 

 sciatic notch. 6 Lesser sciatic notch. 7 Femur. 8 8 Sacro-iliac ligaments, 

 posterior portion. 9 Sacro-spinous. 10 Posterior-sacro-coccygeal ligament. 

 ]1 Obturator ligament. 12 Obturator foramen. 13 13 Upper attachment of 

 the greater sacro-sciatic ligament. 14 Its lower attachment. 15 16 The two 

 attachments of the lesser sciatic ligament. 



