m 



DISEASES OF THE BOXES A^fD Ai;xlC-irLATicr:<TS. 



ABSCESS IN THE SUBSTAXCE OF A BOXE. 



The formation of abscess in the substance of a bone is of rare 

 occurrence, and 1 have only witnessed one marked case of iL 

 The bone is now in my possession, and the two figures represent 

 its external and internal appearances. 



Fig. 27. Fig. 28. 



Pio. 27. — External view of humerus of a horse, with central abscesa. 



Fig. 28. — Internal view of t-ame bone. At a is a well-defined abtsQeaa, 

 containing inspissated pus ; 6 shows the dilated condition of the modtj* 

 larj canal, the cavity being ori<jinally filled with pus. 



An abscess may form within the cancellated structure, whidi 

 is hollowed out, as in the illustration, and is generally situated 

 near the articular extremity of a long bone. The same amount 

 of inflammation necessary to produce pus in the canceJli, would, 

 if situated in the comjjnct tissue, cause necrosis. It is accom- 

 panied by tliiclcening of the outer shell of the bone, as In 

 necrosis. The diagnosis of Internal absoess will be very diffi- 

 cult, on account of tlie depth of its seat The enlarged bone, 

 with pain, will be om only guides until the pus has pierced 



