240 SURGICAL ANATOMY OP 



SURGICAL ANATOMY OF THE HIP-JOINT. 



The hip-joint itself lies inclosed in the foregoing 

 regions, which have been described from the surface in- 

 wards ; and before entering upon a description of the 

 joint itself, it is important to examine the relations of the 

 muscles to the articulation, and their control over its 

 movements, in order to understand the exact position of 

 the head of the femur in the several dislocations to which 

 the joint is liable, and their action upon the upper por- 

 tion of the thigh bone in fractures. 



Immediately in front of the joint is the tendon of the 

 psoas and iliacus (separated from the capsular ligament 

 by a bursa) ; above is the reflected tendon of the rectus 

 femoris and the glutens minimus, closely interwoven 

 with the capsule ; internally the obturator externus and 

 pectineus ; posteriorly the pyriformis, obturator interims, 

 and gemelli, tendon of obturator externus, and quad- 

 ratus femoris (vide Fig. 40). All these muscles are in 

 absolute relation with the capsular ligament, and are 

 covered in by the superficial muscles already described. 



Being an enarthrodial joint, the movements of which 

 it is capable are very extensive : Flexion, which is pro- 

 duced by the psoas and iliacus, sartorius and rectus 

 femoris. Extension, by the hamstrings and some fibres 

 of the glutens maximus. In both these movements the 

 neck of the femur rotates on its axis, whilst the inferior 

 extremity of the thigh bone describes an arc of a circle, 

 directly backwards and forwards. Adduction is per- 

 formed by the pectineus, adductors and gracilis. In 

 this movement the shaft of the femur is adducted to the 

 middle line of the body, and its neck is lowered. Ab- 

 duction, by the glutens medius and minimus, and the 



