338 



SYNDESMOLOGY 



flattened fibers, which cross the acetabular notch, and convert it into a foramen 

 through which the nutrient vessels enter the joint. 



Synovial Membrane (Fig. 343). The synovial membrane is very extensive. Commencing 

 at the margin of the cartilaginous surface of the head of the femur, it covers the portion of the 

 neck which is contained within the joint; from the neck it is reflected on the internal surface of 

 the capsule, covers both surfaces of the glenoidal labrum and the mass of fat contained in the 

 depression at the bottom of the acetabulum, and ensheathes the ligamentum teres as far as the 

 head of the femur. The joint cavity sometimes communicates through a hole in the capsule 

 between the vertical band of the iliofemoral ligament and the pubocapsular ligament with a bursa 

 situated on the deep surfaces of the Psoas major and Iliacus. 



The muscles in relation with the joint are, in front, the Psoas major and Iliacus, separated 

 from the capsule by a bursa; above, the reflected head of the Rectus femoris and Glutseus minimus, 

 the latter being closely adherent to the capsule; medially, the Obturator extern us and Pectineus; 

 behind, the Piriformis, Gemellus superior, Obturator internus, Gemellus inferior, Obturator 

 extern us, and Quadratus femoris (Fig. 344). 



Femoral artery 



Femoral nerve 

 Iliofemoral ligament 

 Rectus femoris 



Femoral vein 



Ligamentum teres 

 Obturator nerve 



Piriformis 



Sciatic nerve 



Obturator internus 



FIG. 344. Structures surrounding right hip-joint. 



The arteries supplying the joint are derived from the obturator, medial femoral circumflex, 

 and superior and inferior gluteals. 



The nerves are articular branches from the sacral plexus, sciatic, obturator, accessory obturator, 

 and a filament from the branch of the femoral supplying the Rectus femoris. 



Movements. The movements of the hip are very extensive, and consist of flexion, extension, 

 adduction, abduction, circumduction, and rotation. 



The length of the neck of the femur and its inclinations to the body of the bone have the 

 effect of converting the angular movements of flexion, extension, adduction, and abduction par- 

 tially into rotatory movements in the joint. Thus when the thigh is flexed or extended, the 

 head of the femur, on account of the medial inclination of the neck, rotates within the acetabulum 

 with only a slight amount of gliding to and fro. The forward slope of the neck similarly affects 

 the movements of adduction and abduction. Conversely rotation of the thigh which is permitted 

 by the upward inclination of the neck, is not a simple rotation of the head of the femur in the 

 acetabulum, but is accompanied by a certain amount of gliding. 



