THE HIP JOINT 



193 



The round ligament (Ligamentum teres) is a strong band which is attached 

 in the subpubic groove close to the acetabular notch, passes outward, and ends 

 in the notch on the head of the femur (Fig. 45G). 



The pubo-femoral ligament (Ligamentum accessorium) does not occur in the 

 domestic animals other than the equidae. It is a strong band detached from the 

 prepubic tendon of the abdominal muscles (Fig. 456). It is directed outward, 

 backward, and upward, passes through the acetabular notch above the transverse 

 ligament, and ends behind the round ligament in the notch on the head of the 

 femur. The origin of the pectineus muscle is perforated by the ligament, which 

 furnishes attachment to tlie greater part of the fibers of the muscle. 



The synovial membrane is reflected over the intracapsular parts of these 



External patellar liginnen 

 Middle patellar lUjamen 



Tuberoaitj/ of tibia 



ExteriKil lateral ligatuent 

 External condyle of tibia 



Shaft of fibula 



Fig. 155. — Left Stifle Joint of Horse, External View, in Partial Flexion. 



The capsules have been removed. 18, Femur; 30, patella; 31, tibia; a", internal patellar ligament; b, external 



femoro-patellar ligament; d, external semilunar cartilage, (.\fter Ellenberger-Baum, Anat. fiir Kiinstler.) 



ligaments and covers the fossa acetabuli. A pouch also extends from the acetabular 

 notch for a variable distance along the subpubic groove alcove the pubo-femoral 

 ligament. 



Movements. — This joint is capable of all the movements of a ball-and-socket 

 joint, viz., flexion, extension, abduction, adduction, rotation, and circumduction. 

 The greatest range of movement is displayed in flexion and extension. When 

 standing at rest, the joint is partially flexed, the articular angle (in front) being 

 about 100° to 115°. The other movements occur to a very hmited extent in normal 

 action. 



Abduction appears to be checked by tension of the round ligament. The pubo-femoral 

 ligament is tensed most promptly by inward rotation of the thigh. 

 13 



