ULCERATION AND SLOUGHING. 197 



400a. Capped Elbow. 



Capped elbow is a serous abscess of a condensed nature, situated at 

 the point of the ulna and forming a soft fluctuating tumour. 



It is generally caused by the heel of the fore shoe in lying down, but 

 may result from any other external injury. Capped elbow rarely pro- 

 duces lameness. 



The treatment consists primarily in reducing the inflammation by 

 fomentations ; and then as the tumour becomes reduced in size, absorp- 

 tion may be promoted by means of an irritant such as ointment of bin- 

 iodide of mercury. If the tumour be large and fluctuating, containing a 

 considerable quantity of fluid, the cyst may be freely opened at the most 

 dependent part, and treated as an ordinary serous abscess. 



It will be necessary to put on a three quarter shoe or tip to prevent a 

 recurrence of the injury. Occasionally setons are employed with benefit. 



CHAPTER 21. 



ULCEBATION AND SLOUGHING. 



401. Definition of Ulceration and Sloughing. 402. Causes of Ulceration. 

 403. Process of Ulceration. 404. Varieties of Ulcers. 405. Treatment. 

 406. Healing process. 



401. Definition of Ulceration and Sloughing. 



Ulceration is that process of nature by which she separates from the 

 living structures those parts which have lost their vitality. It consists 

 in the progressive softening and disintegration of successive layers of the 

 affected tissue. An ulcer may be defined to be a solution of continuity 

 with loss of substance, owing to some action going on in the part itself, 

 which destroys the tissues. It is attended with the secretion of pus. 



Sloughing is the final throwing off of dead tissue from the surrounding 

 structures. Ulceration is the process by which the separation is effected. 



402. Causes of Ulceration. 



The cause may be arrest of nutrition in the part and cessation of the 

 deposition of new material, whilst the old is carried off ; or it may depend 

 on the process of absorption; or it may be an effort of nature for the 

 elimination of dead matter. Again, when from any cause the nutrition 

 of a tissue is altered, and especially if congestion takes place, ulceration 

 is likely to occur. Defective nervous influence is also a predisposing 

 cause. The ulcer always commences where the vitality is least. 



