54 ON THE NAVICULAR DISEASE. 



ration in old and extreme cases of the disease ; for 

 I have, on several occasions, been an eye-witness to 

 the giving way of the flexor perforans tendon at this 

 part, immediately on the animal's being allowed to 

 On neurotomy, get up after the operation of neurotomy, and the 

 pastern let down accordingly. To prove that very 

 many of these advanced cases of navicular disease 

 are altogether improper subjects for the nerve ope- 

 ration, I have repeatedly, on the dissection of such 

 cases (which have been destroyed by their owners 

 rather than have them submitted to the operation), 

 observed the tendon so attenuated by absorption 

 opposite the caries of the bone, that, upon holding 

 it up between the light, I could distinctly see 

 through its few remaining fibres. 



This single pathological fact clearly shews the 

 control which is reserved to the afflicted animal 

 over his extensor muscles, in rendering them sub- 

 servient to the flexors, and thereby averting the rup- 

 ture of this disorganized part ; and which is never 

 known to happen, however extensively diseased, 

 unless neurotomy has deprived it of feeling. 



Notwithstanding these unsuccessful cases, 1 have 

 much to say in favour of the nerve operation, for 

 the practical utility of which we are unquestionably 

 indebted to Mr. Wm. Sewell, of the Royal Veteri- 

 nary College ; liuti feel no reluctance in postponing 

 jny remarks on that subject lo a future o})portnni( y, 

 seeing that its merits and demerits are now under 



