PRINCIPLES OF VETERINARY SURGERY 337 



sensitive scars that provoke a continuation of the lameness, 

 in spite of the division of the nerve. 



Keloids are real fibrous tumors generated on irritable, 

 projecting scars. They are the expression of a too active 

 cicatricial process, and of an over-abundant cellular hyper- 

 plasia. They may develop in different ways after insignifi- 

 cant wounds. 



They reappear and extend after ablation. Their origin 

 has not been accurately determined. They may follow the 

 most trifling lesion and develop in animals in perfect health. 

 Slight but continuous irritations of wounds in the course of 

 cicatrization seem to be the cause in many cases. They 

 may acquire considerable dimensions and weigh many kilo- 

 grams. They occur in the form of large, reddish, oozing 

 tumors that bleed easily. They are complicated with lym • 

 phangitis and often render the svibject useless. 



The observations published on this subject by Labat are 

 very interesting. 



PATHOLOGICAL ANATOMY.— Cicatrix. Tissue in 

 the course of cicatrization, besides very numerous vascular 

 plexi and different connective elements, contains special 

 cells termed fibroblasts containing a highly colored nucleus 

 and a granular protoplasm provided with extensions v hich 

 meet progressively in connective fascic'uli. The develop- 

 ment of the connective tissue takes place rapidly. By de- 

 grees the connective cells are flattened and smoothed out, 

 and then assume the physiognomy of ordinary connective 

 tissue. Simultaneously the rest of the tissue is modified.. 

 The newly formed blood-vessels sink, retract, atrophy and 

 disappear without leaving any traces of their existence ex- 

 cept some ansemiated cells and some canaliculated capil- 

 laries. 



Thus the scar tissue is produced. It is a tissue that is 

 desiccated as much as the granulation, its generator, was 

 succulent ; ischemic as much as the other was largely irri- 



