The Lower Extremity and Pelvis 



141 



is the orbicular zone of circular fibres of the capsule, which is a broad band 

 extending to the neck of the bone (Fig. 105). This band is not as a whole continuous 

 with the cotyloid ligament, but is lined by synovial membrane which passes in on 

 the superficial aspect of the cotyloid ligament (in the posterior part of the joint) and is 

 then reflected back over it on to its deep or articular surface. 



The circular band appears to derive its fibres from the deep tendons of the gluteal 

 musculature and from the reflected head of the Rectus (Fig. 105). At the lower part of 

 the neck many of its fibres pass into the 

 inferior retinaculum. It covers in the 

 synovial membrane on the neck and 

 closely surrounds the bone, thus acting as 

 a kind of suction pad in resisting separa- 

 tion between the two bones. 



The transverse fibres cover the 

 circular zone in front : they are transverse, 

 or nearly so, to the plane of the joint, but 

 they are more nearly vertical in their 

 relation to outside planes. They form a 

 broad and very thick mass of fibres 

 extending from the front margin of the 

 innominate bone to the anterior intertro- 

 chanteric line. The mass varies in thick- 

 ness and direction of its fibres, those 

 attached to the anterior inferior spine 

 being exceedingly thick and diverging to 

 reach the intertrochanteric line, while 

 further in the fibres attached to the 

 upper pubic ramus are thinner and con- 

 verge to the lower end of the intertro- 

 chanteric line and the recurved part of it : 

 the thick part is termed the ilio-femoral 



band or Y-shaped ligament of Bigelow, 

 and the inner one is the pubo-femoral 

 band. 



The ilio-femoral ligament receives 

 some fibres of Iliacus, which lies with 

 the Psoas on its front surface. The pubo- 

 femoral band is covered by Pectineus 

 and near the femur by Psoas. The 

 tendon of Rectus lies on the ilio-femoral 

 band outside Iliacus, and external to the 



FIG. 115. A diagrammatic sketch to illustrate the 

 relations of the hip from the front. The capsule 

 is seen exposed in the centre of the drawing. 

 The femoral sheath is cut, and the artery seen 

 resting in the sheath on the cut Psoas ; outside 

 this is the cut Iliacus. If these muscles were not 

 removed they would cover the front of the 

 capsule. The tendon of Rectus appears from 

 under the outer edge of Iliacus, cut short ; it 

 rests on the ligaments. It emerges between a 

 thin fascial sheet from Poupart's lig. round 

 Iliacus and the thicker covering of the gluteal 

 group externally. Inner part of the sheath lies 

 on and is fused with the fascia on Pectineus ; 

 a small area of fascia remains showing how it 

 extends under Psoas and reaches the pubo- 

 femoral band. 



tendon the joint is covered by Gluteus 

 minimus. Aponeurotic fasciae cover the Gluteus and the Iliacus and are attached 

 to the Rectus tendon between them, passing back on each side of this to gain 

 attachment to the capsule ; another sheet from the pubic fascia or Pectineus fascia 

 goes under Psoas to reach the pubo-femoral band and the bone above it (Fig. 115). 

 The circular zone behind is covered by Gluteus minimus, Pyriformis, Obturator 

 internus and Gemelli, and Obturator externus is in relation with its lower and back 

 aspect (see Figs. 107 and 108). 



The Ligamentum teres is a weak synovial attachment of the head of the femur to 



