398 DISTORTION OF THE NECK. 



the head, get the hind-foot fixed in the halter and are thrown, or in 

 jibbers, which have been pulled forward by a rope passed round the 

 neck. 



Diagnosis. The conditions described cannot always be 

 differentiated, even on careful examination. Cognisance must be 

 taken not only of the symptoms, but of the history of the case. 

 Distortion produced by muscular disease is usually distinguished 

 by pain, swelling, and other inflammatory changes, while the neck, 

 although it may be brought into its normal position, reverts to its 

 distorted state when force or support is removed. Cicatrices are 

 a rare cause in the lower animals. When inflammatory appearances 

 are absent, paralysis of the muscles on the convex aspect of the neck 

 may be suspected, especially if cicatricial contraction can be excluded 

 as a cause. 



Distortions arising from fractures and subluxations may be dis- 

 tinguished from those connected with muscular lesions by crepitation, 

 and still more notably by the fact that the parts, even if difficult 

 to bring into position, retain that position when once reduced. Many 

 observers state that in subluxation the neck is excessively mobile ; 

 but although it may be so in certain directions, general freedom of 

 movement is diminished. Egelling saw what he considered to be 

 persistent luxation of the cervical vertebrae. The horse could even 

 be ridden. 



Slight curvatures usually produce little inconvenience, but 

 considerable displacement of the head leads to difficulty in movement, 

 and the animal is sometimes unable to get up or to stand, though 

 it can do both immediately the head is supported in its normal position. 

 Others make " circus movements " towards the side to which the 

 neck is curved. Where curvature becomes excessive, as is frequently 

 the case in dogs and rabbits, the animals attempt to rise, but at 

 once fall back, and make rolling movements around the long axis 

 of the body. This is occasionally seen in dogs with disease of the 

 middle ear, and in rabbits affected with mange of the ear. Some- 

 times, in horses which have suffered from severe strain of the collective 

 muscles of the neck, the head is carried very low, producing con- 

 siderable cedematous swelling, and causing the animal's head to 

 resemble that of a hippopotamus. 



Ruptures of the funicular portion of the ligamentum nuchae 

 can be directly felt and recognised by the head being carried very 

 low. The same position is assumed in disease of the upper vertebrae, 

 and of their joints. Moller had a horse with purulent arthritis 

 between the first and second cervical vertebrae, produced by the 



