THE STUDY OF THE MUSCULAR SYSTEM 81 



stimulating embrocations are to be avoided, as they have a tendency 

 to consolidate the effused products. Some animals get capped hocks 

 by scraping all their litter behind them, and then lying down on the 

 bare brick or pavement. This may be remedied by bedding thickly 

 with sawdust or moss-litter. When the swelling is very large it 

 may be opened and the watery fluid drawn off, but great care is 

 required to distinguish the serous effusion from the synovial secre- 

 tion, and if the synovial bursa is punctured it might lead to 

 serious consequences. The synovial capped hock is generally not 

 so painful as the serous variety, but is more deeply seated, and 

 is best treated by repeated applications of 20 per cent, of oleate 

 of mercury. 



159. Curb. — An enlargement seen on the back and lower part of 

 the hock joint where the heads of the small metatarsal bones join the 

 lower row of bones of the hock (Plate IX., No. 38). There are two 

 kinds of curb, false and true. False curb is an effusion of serum 

 under the skin, due to a sharp blow on the part. The treatment for 

 it consists of hot fomentations or cold water applications, followed 

 by an iodine blister (par. 1066, No. 3). 



160. True Curb is of a more serious nature, and consists either of 



a sprain of the tendons passing over the seat of curb or laceration of 



the calcaneo -cuboid ligament at its attachments to the cuboid and outer 



small metatarsal bone. This is caused by overexertion, as when 



galloping, jumping, rearing up, etc. Some breeds of horses have 



joints naturally predisposed to curb — called curby or sickle hocks 



and therefore of congenital formation. In sickle hocks the head of 



the metatarsal is set too far back ; and the OS calcis, the upper end 



of which forms the point of the hock, is too short and straight up, 



forming a narrow joint, or ' tied-in ' hock, with a sharp angle at the 



lower part of the front of it. This class of joint is more subject to 



curb than a well-formed, broad, and developed one. When the 



enlargement is seen, and the animal is noticed to be lame or the part 



found to be tender, it should be put off work, and cooling applications 



used — such as the hose-pipe irrigation of cold water or a cold water 



6 



