The Locomotor Apparatus. o27 



condition, ' dishing,' are influenced not only by the elbow, 

 but by the shape of the articular surfaces between the 

 radius and upper row of bones. 



The radius is peculiar in presenting on that articular 

 surface next the knee a concave surface anteriorly and a 

 convex one posteriorly ; these form two condyles, of which 

 the inner is more curved than the outer. The outer 

 condyle plays on the trapezium, cuneiform, and lunar : the 

 inner condyle plays solely on the scaphoid. When the 

 knee is flexed the influence of the condyles is seen ; the 

 concave articular surface of the radius is removed from 

 the surface of the bones of the knee, and the convex 

 articular surface appears as the joint grows wider. The 

 inner condyle being larger than the outer depresses the 

 scaphoid, so that a very important movement occurs 

 between the scaphoid and lunar ; this action of the radius 

 on the scaphoid throws the foot slightly outwards, probably 

 with the object of enabling it to clear the opposite limb. 

 I believe that an examination of the knees of ' dishing ' 

 horses will show that extreme curvature of the inner 

 condyle of the radius is the cause of the action, in the same 

 way that turned-in elbows and alterations in the curvatures 

 of the radius and humerus will probably account for horses 

 throwing the lower part of the leg inwards, and thus 

 ' brushing ' or ' speedy cutting.' 



The Fetlock forms a flexible articulation : in a state of 

 repose the greater part of the horse's weight is borne on 

 the posterior half of the metacarpal articulation, and the 

 articular surface of the sesamoids. The influence exercised 

 by the sesamoids by being attached both above and below 

 to ligamentous structure is dealt with in the next para- 

 graph. For the movements of the foot-joint, see the 

 Chapter on the Foot. 



The Function of the Suspensory Ligament has been a 

 fruitful source of discussion. Its chief use, no doubt, is to 

 support the fetlock ; in no other way could a joint placed 

 in such a part of the limb, possessed of so much motion, 

 and exposed to such concussion, be supported. Though 



