278 



THE ARTICULATIONS 



On laying open the capsule, some of the deeper fibres are seen reflected upward along the 

 neck of the femur, to be attached much nearer the head: these are the retinacula. One corre* 

 sponds to the upper, and another to the lower, part of the intertrochanteric line; a third is seen 

 at the upper and back part of the neck. They form flat bands,which lie on the femoral neck. 



Superadded to the capsule, and considerably strengthening it, are three auxil- 

 iary bands, whose fibres are intimately blended with, and in fact form part of, 

 the capsule, viz., the iho-femoral, ischio-capsular, and pubo-capsular ligaments. 



The ilio-femoral ligament (fig. 306) is the longest, widest, and strongest of the bands. 

 It is of triangular shape, with the apex attached above to a curved line on the ilium immediately 

 below and behind the anterior inferior spine, and its base below to the anterior edge of the 

 greater trochanter and to the spiral fine as far as the medial border of the shaft. The highest or 

 most lateral fibres are coarse, almost straight, and shorter than the rest; the most medial fibres 

 are also thick and strong, but obhque. This varying obliquity of the fibres, and their accumula- 

 tion at the borders, explain why this band has been described as the Y-shaped ligament; but it 



Fig. 307. — Upper Extremity of the Femur (Anterior View), to snow the Relation 



OF the ARTICtTLAR CaPSULE OF THE HiP-JOINT (iN RED) TO THE EPIPHYSIAL LiNES. 



should be noted that the Y is inverted. About the centre of its base, near the femoral attach- 

 ment, is an aperture transmitting an articular twig from the ascending branch of the external 

 circumflex artery. 



Tlie ischio-capsular ligament (fig. 308) is formed of very strong fibres attached all along 

 the upper Ijorder of tlie groove for the external obturator, and to the ischial margin of the ace- 

 tabulum above the groove. The highest of these incline a little upward as they pass laterally 

 to be fixed to the greater trochanter in front of the insertion of the piriformis tendon, while the 

 other fibres curve more and more ui)ward as they pass laterally to their insertion at the inner 

 side of the trochanteric fossa, blending with the insertion of the external rotator tendons. When 

 the joint is in flexion, these fibres pass in nearly straiglit lines to their femoral attachment, and 

 spread out uniformly over the head of the femur; but in extension they wind over the back of 

 the femur in a zonular manner [zona orbicularis], embracing the posterior aspect of the neck 

 of the fetiuir. 



The pubo-capsular (pectineo-femoral) band (fig. 306) is a distinct but narrow set of fibres 

 which are individually less marked than tlie fibres of the other two bands; they are fixed above 

 to the obturator crest and to the anterior border of the ilib-pectineal eminence, reaching as far 

 down as the pubic end of the acetabular notch. Below, they reach the neck of the femur, and 

 are fixed above and behind the lowermost fibres of the ilio-femoral band, with which they blend. 



