THE ANATOMY OF THE HORSE 27 



capsular and lateral binding ligaments, same as fetlock joint. 

 It also has the same motion as fetlock joint, and is some- 

 times the seat of what is termed a high ringbone. 



8. Coffin Joint. — This joint is situated within the hoof 

 of the horse. It is formed above by the lower end of the 

 small pastern bone, and below by the upper part of the foot 

 bone, or os pedis. Immediately behind this joint, and artic- 

 ulating with the other two bones, is the navicular, or shuttle 

 bone — it gets its name from its likeness to the shuttle of a 

 sewing machine. This bone when diseased is the seat of 

 navicular disease, or otherwise called coffin-joint lameness. 

 It is also affected with what is sometimes called a low-down 

 ringbone. 



II. Joints of Hind Leg. 



9. Hip Joint. — This is a ball-and-socket joint, similar to 

 shoulder joint. It has a capsular ligament and what is called 

 a round ligament, in the joint, holding tbe head of the bone 

 in the socket. This can be seen plainly by examining the 

 joint. This is an important ligament, as it often becomes 

 strained, being the seat of hip joint lameness. It is also held 

 together by the heavy muscles of the hip. Its motion is sim- 

 ilar to that of shoulder joint. 



10. Stifle Joint. — This joint is formed above by the lower 

 end of the femur, or hip bone, and the upper end of the tibia, 

 or thigh bone. These two bones in front form a pulley-like 

 surface on which the patella, or stifle bone, is situated. This 

 bone, when the joint is in motion, glides up and down over 

 the pulley-like surface. It sometimes becomes displaced, and 

 this is termed dislocation of the stifle bone. This is an im- 

 portant point to notice about this joint. It has a capsular 

 and lateral, or binding ligaments; also three very important 

 ligaments, called the straight ligaments, which hold the stifle 

 bone to its place as it plays upon the pulley-like process of 

 this joint. The motion is backward and forward, same as 

 elbow joint. 



11. Hock or Tarsus Joint. — This joint contains six bones. 

 The two upper bones, one of which is a pulley-like bone 

 placed in front, and the other one placed behind, forms that 

 part of the hock which is called the point of the hock to 

 which the muscles of the gamb are attached. It can be easily 

 seen or felt. The upper surface of these two bones articulate 



