242 LAMENESS. 



by loss of substance (atrophy), and sometimes by fatty degene- 

 ration of its fibres, whereby they lose their red fleshy appear- 

 ance, and assume that of wliitish threads of fat. When micro- 

 scopically examined, the sarcous elements — the real contractile 

 tissue within the sarcolemma — is replaced by glistening oil 

 particles, so that the functional power is completely destroyed. 

 If the whole muscle be involved, its contractile • power no longer 

 exists ; and this loss of power will vary according to the extent 

 of the muscular structure involved in the primary lesion. 



Atrophy of the fibrillae, and consequent fatty degeneration 

 of their contents, is often due to pressure by an inflammatory 

 exudate formed in the spaces of their connecting areolar tissue ; 

 and it is important, practically, to remember this, for the reason 

 that the sooner an exudate can be removed, the less chance 

 there is of degenerative changes taking place in the true mus- 

 cular elements. 



The changes that occur in inflammation of muscular tissue, 

 whether arising from strain or other causes, may be briefly de- 

 scribed thus : — Is;;. Swelling from congestion and exudation ; 

 2cl. Atrophy, from the pressure of the exudate upon the muscu- 

 lar fibrillse, and from loss of function ; od. Fatty degeneration of 

 the sarcous elements, and permanent loss of contractility. 



Treatment. — Eepose; soothing applications, succeeded by 

 slight, and afterwards stronger irritants. Purgatives and cool- 

 ing diet at first, followed by good nursing. 



STRAIN OF THE PSO.^ MUSCLES. 



Much confusion prevails among veterinary surgeons as to the 

 jiroper diagnosis of this injury, some classifying all cases of in- 

 ability, or paralysis of the hind limbs, unless broken back can be 

 detected, as sprain of the psoas muscles ; whilst others deny the 

 existence of such an injury at all. 



Sprain of the psoee muscles simulates paralysis, broken back, 

 and that mysterious disease which has been erroneously termed 

 hysteria by Mr. Haycock, — a disease which, in reality, is due to 

 the presence of a large amount of effete materials, especiady urea, 

 in the circulation, and which may be termed AzoTUKiA. 



The psoai muscles — magnus and parvus — are, along with the 

 iliacus, sartorius, &c., situated within the pelvic and sub-lumbar 



