HIP LAMENESS. 955 



(4) Until the typical peripheral nerve lamenesses were first 

 recognised they also were included under the description " hip 

 lameness." It is possible that certain cases described as hip lameness 

 are due to functional disturbance of the sciatic, crural, or obturator 

 nerve. As already stated, Gunther describes cases produced by 

 paralysis of the lumbar nerves. The descriptions of neuralgia of 

 the sciatic nerve in animals are unconvincing ; certainly the occur- 

 rence of this condition has not yet been clearly proved. 



(5) Finally, disease processes near the hip-joint may produce 

 lameness, the real cause of which either remains undiscovered, or is 

 only revealed after very careful examination. Scirrhous cord, 

 swelling of the inguinal glands, inguinal and femoral hernia?, all 

 interfere with movement, and sometimes produce lameness, simulating 

 that due to disease of the hip-joint, or of the bones or muscles. In- 

 flammation of the subcutis over the hip -joint may also result in 

 lameness. 



Symptoms. Although the various forms of hip lameness, being 

 due to different causes, exhibit important peculiarities in their 

 symptoms, yet, taken as a whole, they show certain features of general 

 agreement. Thus in all there is difficulty in advancing the limb 

 (swinging leg lameness), retardation of movement and shortening 

 of the forward stride, and in many a tendency to stiffen the limb 

 during movement and to drag the toe. When the hip -joint itself 

 is diseased, there is supporting leg lameness, and the animal tries 

 to avoid throwing weight on the affected side — symptoms which 

 are usually absent in the purely muscular forms. Lameness is marked 

 when turning and backing, and appears in an aggravated form after 

 severe exertion. Sometimes it is most distinct when commencing 

 work, and gradually decreases ; sometimes the reverse. Though 

 rheumatic lameness usually wears off with exercise, the continuance 

 or aggravation of lameness under such circumstances by no means 

 points to a traumatic origin. Mechanical injury is a much more 

 frequent cause of lameness than rheumatism. 



Sometimes anatomical changes, such as muscular atrophy, swelling 

 and increased warmth, which can be detected, assist diagnosis, and 

 render it approximately exact. The more thorough and complete the 

 examination, the less common will be the diagnosis " hip lameness," 

 which we are only justified in delivering when careful examination 

 shows no visible cause elsewhere for lameness. 



In other words, diagnosis must be arrived at by a process of 

 exclusion. Cases occur, however, which even the most practised 

 fail exactly to trace to their source, 



