116 



LIGAMENTS OF THE PELVIS. 



Fig. 51.* 



brane, which cannot be demonstrated in the adult ; but is apparent 

 in the young subject, and in the female during pregnancy. 



2. Between the Sacrum and Ischium. The anterior or lesser sacro- 

 ischiatic ligament is thin, and triangular in form ; it is attached by 



its apex to the spine of the 

 ischium ; and by its broad ex- 

 tremity to the side of the sa- 

 crum and coccyx, interlacing 

 its fibres with the succeeding. 

 The anterior sacro-ischiatic 

 ligament is in relation in front, 

 with the coccygeus muscle, 

 and behind with the posterior 

 ligament, with which its fibres 

 are intermingled. By its up- 

 per border it forms a part of 

 the lower boundary of the 

 great sacro-ischiatic foramen, 

 and by the lower a part of the 

 lesser sacro-ischiatic foramen. 

 The posterior or greater sa- 

 cro-ischiatic ligament, consi- 

 derably larger, thicker, and 

 more posterior than the pre- 

 ceding, is narrower in the middle than at each extremity. It is 

 attached by its smaller end, to the inner margin of the tuberosity 

 and ramus of the ischium, where it forms a falciform process, which 

 protects the internal pudic artery, and is continuous 'with the ob- 

 turator fascia. By its larger extremity it is inserted into the side of 

 the coccyx, sacrum, and posterior inferior spine of the ilium. 



The posterior sacro-ischiatic ligament is in relation in front with 

 the anterior ligament, and behind with the gluteus maximus, to some 

 of the fibres of which it gives origin. By its superior border it 

 forms part of the lesser ischiatic foramen, and by its lower border, 

 a part of the boundary of the perineum. It is pierced by the coc- 

 cygeal branch of the ischiatic artery. The two ligaments convert 

 the sacro-ischiatic notches into foramina. 



3. Between the Sacrum and Coccyx, The anterior sacro-coccy- 

 geal ligament is a thin fasciculus passing from the anterior surface 

 of the sacrum to the front of the coccyx. 



The posterior sacro-coccygean ligament is a thick ligamentous layer, 



* Ligaments of the pelvis and hip-joint The view is taken from the side. 1. The 

 oblique sacro-iliac ligament. The other fasciculi of the posterior sacro-iliac ligaments 

 are not seen in this view of the pelvis. 2. The posterior sacro-ischiatic ligament. 3. 

 The anterior sacro-ischiatic ligament. 4. The great sacro-ischiatic foramen. 5. The 

 lesser sacro-ischiatic foramen. 6. The cotyloid ligament of the acetabulum. 7. The 

 ligameutum teres. 8. The cut edge of the capsular ligament, showing its extent pos- 

 teriorly as compared with its anterior attachment. 9. The obturator membrane only 

 partly seen. 





