LUXATION OF THE FEMUR. 57 



Finally, luxation may be either complete (in which case the capsular 

 and interosseous ligaments are both ruptured) or incomplete. In the 

 former case, the head of the femur becomes displaced upwards and 

 forwards towards the great sciatic notch, more rarely backwards in the 

 direction of the ischium, and in exceptional cases downwards and 

 inwards below the pubis into the foramen ovale. 



Symptoms. The symptoms vary, depending on whether the luxation 

 is of the spontaneous, progressive order or, on the contrary, is accidental. 

 In progressive luxation, the animals are able to rise and walk with 

 difficulty. The affected limb swings when the animal is advancing, not 

 as though it were paralysed, but simply as though displaced at its upper 



Fig. 21. — Accidental luxation of the hip joint. 



part. Pain is exhibited when weight is placed on the limb, and there is 

 difficulty in movement. The limb appears shorter than its neighbour 

 when the animal stands on it, and the prominence representing the 

 trochanter is more marked. When a false joint has formed, the limb is 

 rigid, is moved stiffly and abducted, and the stride is shortened. 



In accidental luxations, either of one or both limbs, the attitude 

 assumed by the animal is often characteristic. One of the limbs is ex- 

 tended at right angles to the longitudinal axis of the body, and some- 

 times both limbs assume this position, an attitude which would be 

 absolutely impossible under normal conditions. The animal cannot 

 rise. It lifts the front part of the body by rising on its knees, but the 

 hind quarters do not follow. The ruptured adductor muscles are unable 

 to bring and hold the limb parallel to the longitudinal axis of the body ; 

 the abductors act unopposed, and at the moment when the animal makes 



