954 HIP LAMENESS. 



and the results of post-mortem examination support this view, though 

 occasionally the disease does oeeur in animals. In dogs, it often 

 causes chronic hip lameness, and it has been seen in foals. 



(2) Another cause of hip lameness is disease of the bones, i.e., 

 of the lumbar vertebrae, pelvis, and femur. Old fractures of the 

 pelvis sometimes occasion obscure lameness. In one such case Bayer 

 ( let eeted fracture of the os pubis. On superficial examination, fracture 

 of the external angle of the ilium may be mistaken for hip lameness, 

 as may fracture of the trochanter of the femur. Under the title 

 trochanteric lameness, Williams describes a disease of the upper 

 trochanter in the horse, manifested by chronic inflammation and 

 formation of exostoses. 



(3) The cause of hip lameness is more often to be sought in the 

 muscles than in the hip-joint and the bones. In lameness following 

 external injuries, bruises, sprains, and partial ruptures (in conse- 

 quence of falls, kicks, collisions, or over-exertion), the seat of disease 

 is often in the muscles, especially in the superficial layers. 



Particular attention should be directed to disease of the tendon 

 and tendon bursa of the gluteus medius muscle, to thrombosis of the 

 iliac arteries, and in cattle to displacements of the biceps femoris. 

 In exceptional cases, this also occurs in the horse. 



Kutzner, in a horse, noted gradually increasing atrophy of the biceps 

 femoris muscle and of the upper portions of the semi-tendinosus. Lame- 

 ness only appeared after three or four months, when atrophy was far 

 advanced ; the foot was add acted just before the end of the stride, and set 

 down too far under the body. The horse showed weakness in movement, 

 and after lying on the diseased side was unable to rise. Kutzner referred 

 the condition to thrombosis. Roloff noted paralysis of the gluteus 

 maximus in a heavy draught-horse. When walking the affected leg was 

 advanced further than its neighbour, and was drawn towards the opposite 

 side, causing the hindquarters to roll towards the sound side at every step. 

 The animal had great difficulty in moving backwards, dragged the foot 

 along the ground, and could scarcely advance it beyond that of the opposite 

 side. Dining movement, the thigh was strongly flexed, but only partially 

 extended. The animal showed no pain whatever. The muscle gradually 

 became atrophied, and its place was finally occupied by a trough-shaped 

 depression. 



K. Giinther describes a similar case, which he refers to paralysis of the 

 Lumbar plexus. In this case the limb was so excessively extended during 

 movement that the hoof even touched the chest or elbow. It was, however, 

 still capable of sustaining weight. At a later stage the muscles of the 

 quarter showed marked atrophy. 



Noack found rupture of the tensor vaginae femoris muscle just below its 

 insertion into the external angle of the ilium. The horse became sound in 

 a month. Frankc's case of atrophy of the muscles of the quarter in con- 

 sequence of paralysis of the gluteal nerves has already been alluded to (vide 

 "Paralysis of the Gluteal Nerves"). 



