OF THE BONES. 385 



production, is sometimes formed of organizable substance, 

 which after having distended and dilated the natural bone, 

 at last ossifies more or less completely in its interior. 



607. When a bone is denuded of the periosteum,* if the 

 subject is young, if the bone itself be not altered, and if it has 

 not remained long uncovered, the wounded soft parts, if re- 

 stored to their natural position, unite by first intention. 



Under contrary circumstances, and in those in which the 

 inflamed periosteum separates from the bone by suppuration, 

 in that in which it becomes gangrenous, and when the peri- 

 osteum suppurates or mortifies, &c. the bone, deprived of its 

 nutritive apparatus, becomes affected with necrosis at its sur- 

 face, and to a greater or less depth. The living part in the 

 vicinity of the dead portion, becomes inflamed, softens, is at 

 length detached from the part affected with necrosis, and sup- 

 purates. The dead portion having thus become free, falls off. 

 The subjacent granulations at length produce a cicatiix which 

 covers the bone, adheres to it, and forms a new periosteum. 



608. After amputation,t matters go on in one or other of 

 the two ways above described. 



When the bone and its nutritive apparatus have not been 

 hurt above the amputated place, and especially when the union 

 of the wound is immediate, the end of the bone commonly 

 unites by first intention with the soft parts. 



On the contrary, when the wound remains open and sup- 

 purates, when the periosteum has been torn or detached above 

 the place of amputation, or when the medullary membrane 

 has been irritated and inflames, the end of the bone becomes 

 affected with necrosis, and there is detached a slice compre- 

 hending its whole thickness, and generally gaining obliquely 

 upon its outer surface, because the periosteum is commonly 

 more injured, or is injured higher than the medullary mem- 

 brane. 



* Tenon. Three Memoirs on Exfoliation of the Bones, in Mem. et Obt. 

 sur TJLnaL Pathol et la Chir. &c. Paris, 1816. 



f Van Home. Dissertatio deiis, quse inpartibus membri, preesertim osseis, 

 amputations vukieratis, notanda sunt. Lugd. Bat. 1803. L. L. Brachet, 

 Mtm. de Phys. Path, sur ct que devient k fragment de Pos apres une Amputa- 

 tion, in Sullet.de la Soc. Med. d> Emul de Paris, 1822. 



