160 



ARTICULATIONS OF THE PELVIS. 



back part of the iliac fossa, Avherc its fibres expand somewhat, so as to 

 give it a triangular form. 



Articulatiox of the Sacrum and Coccyx, and of the Pieces 

 OF THE Coccyx. — These articulations are effected by an anterior liga- 

 ment, consisting of irregular fibres placed in front of the bones, a pro- 

 longation of the anterior common ligament of the vertebrai; by a 

 posterior ligament more strongly marked, the fibres of which descend 

 upon the bones of the coccyx from the margin of the inferior orifice of 

 the sacral canal ; by fibrous bands extending between the cornua of the 

 sacrum and coccyx ; and by interverteliral discs between the con- 

 tiguous surfaces of the bones. 



A distinct cavity is stated by Ciuveilhier (" Anatomic descriptive,"' torn. i. 

 p. i50.5. Paris. 1862). to be present in the centre of the disc in those cases in 

 wliich the coccyx is freely moveable. This is in conformity ■with the more recent 

 observations of Luschka on the other intervertebral discs. In the male, after 

 middle life, the union between the sacrum and coccyx, and lietween the pieces 

 of the latter, is usually cssific. In the female this change does not generally 



Fi?. li'). 



Fig. 145. — AuTicuLATioNS OP THE Pelvis and Hip-Joint, seen i'kum befoke. The 



ANTERIOR HALF OF THE CAPSULAR LiGAMENT OF THE LeFT HiP-JOINT HAS BEEN 

 REMOVED, AND THE FeMUR KOTATED OUTWARDS. (A. T.) ^ 



1, 1, anterior common ligament of the bodies of the vertebrre passing down to •the 

 front of the sacrum and coccyx ; 2, ilio-lumbar ligament ; 3, anterior sacro-iliac liga- 

 ment ; between 2 and 3, on the right side, the sacro-vertebral ligament i.s showTi, bnt not 

 with sufficient distinctness ; 4, placed in the great sacro-sciatic foramen, points to the 

 lesser sacro-sciatic ligament ; 5, a portion of the gi-eat sciatic ligament ; 6, the anterior 

 ligament of the symphysis pubis ; 7, the obturator membi-ane ; 8, the capsular ligament 

 •of hip-joint : the figure is placed on its ilio-femoral band ; 9, the upper part of the 

 divided cajisular ligament of the left hip-joint near the place of its attachment to the 

 border of the acetabulum ; 10, i>laced on the os pubis of the left side above the trans- 

 verse ligament of the acetabular notch. The liead of the femur is withdra-wn partially 

 from the socket, so as to show the round ligament stretched from the transverse 

 ligament. 



