We now come to the fetlock-joint, where one or more of a variety of diseases incidental to it may be found. One or both of the sesamoid bones are sometimes enlarged, and here again they should be compared one with the other and with those of the opposite limb, lest slight but important changes be overlooked.

The joint, as a whole, may be swollen from a general sprain of its structures, or from hard and prolonged wear; but it must be borne in mind that all swellings of this part are not attributable to these causes.

Some, which are commonly spoken of as "filled" legs, are generally the outcome of slight temporary disturbance of the general system, and will disappear when that disturbance ceases to operate. In special cases this defect may result from a weak heart, in which case it would most likely be permanent or periodic, and the cause of it an unsoundness.

Bony growths of one sort or another are not seldom found in the region of the joint involving either the canon or long pastern, or both. Such formations are, for the most part, an unsoundness; but the same cannot be said of all. Brushing or interfering is often accountable for enlargement of the inner aspect of the joint, and should receive special attention at this stage of the examination. The effect of this mishap may be serious or not, but all horses whose conformation and action predispose to it should be declined.

Distention of the synovial sheaths of tendons which pass over the fetlock-joint behind, or of the capsular membrane of the joint, is commonly observed in smaller or larger bulgings termed " windgalls".

These may be the progressive result of severe work, or arise out of sprain or other injury to the part. In their slighter forms they are unimportant, unless there is evidence of a hereditary predisposition to their formation. This will most likely exist where similar developments are observed in and about other joints, such as thoroughpins, bog spavins, and the like. Where, however, they are large, tense, and resisting, action will be interfered with, and they must, in such circumstances, be regarded essentially as an unsoundness.