CAUSES OF LAMENESS. 237 



in a limb without lameness than lameness without disease. 

 Thus, a horse may have a wound, ulcer, bony deposit, or a 

 tumour, without evincing lameness. From these particulars we 

 may argue that lameness is never present without pain, although 

 Percivall asserts that inability, in the absence of pain, will be 

 found as a cause of lameness, and he says — " Dislocation of the 

 patella occasions no pain, and yet the horse is too lame even to 

 move. The partial or complete anchylosis of a joint may cease 

 to be attended with pain, and yet there may be permanent and 

 irremoveable lameness." I think we may safely take exception 

 to these conclusions, as they are not borne out by every-day 

 experience. 



Complete anchylosis may exist without pain, and yet the 

 patient is lame ; but it will be found that such anchylosis exists 

 in some joint of extensive motion, and prevents flexion and ex- 

 tension in the whole limb. 



Pain, then, may be generally said to be the common cause of 

 lameness. The patient feels the pain either when it moves the 

 limb, or when it bears weight or presses upon it. During motion 

 the patient endeavours to avoid throwing pressure upon the lame 

 limb, by treading lightly or stepping short, and by removing 

 weight as far from the seat of pain as it possibly can, not only 

 by using the lame limb in a manner best calculated for this 

 purpose — as by treading on the heels when the pain is in the 

 anterior part of a limb or foot, and upon the toes when in the 

 posterior part — but also by throwing the w^eight from the lame 

 limb as much as it possibly can. 



Weakness of the limbs may cause lameness and inability to 

 perform the function of progression properly. A characteristic 

 example of this has been described by Mr. George Armatage, 

 under the title of " Congenital Muscular Atony," or a want of 

 development of muscular fibre in the extensor muscles of the 

 fore arm of foals. In this form of lameness the animal stands 

 almost upon the front part of the fetlock-joints ; the flexor 

 muscles healthy, fully developed, and having no antagonistic 

 power opposed to them, in consequence of the arrested develop- 

 ment of the extensors, draw up the limbs posteriorly ; the heel 

 of the foot and the fetlock pad being in close contact, the little 

 animal beino^ at the same time almost unable to move. I have 

 found this kind of lameness occurring at any time during the 



