THE ANATOMY OF THE HORSE. 15 



Stifle Joint. — ^This joint is formed above by the lower end ot 

 the femur, or hip bone, and the upper end of the tibia, or thig^h 

 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, g^lides up and down over the pulley-like surface. 

 It sometimes becomes displaced, and this is termed dislocation 

 of the stifle bone. This is an important 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 holds the stifle bone to its place as it plays upon the pulley- 

 like process of this joint. The motion is backwards and forwards, 

 same as elbow joint. 



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

 two upper bcnes, 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, which can be easily seen or felt. The upper 

 surface of these two bones articulate with the lower extremity of 

 the tibia, or thigh bone, and forms a true articulation of the hock 

 joint. This part is what gives most of the motion to the 

 joint. Below those we find three other small, flat bones, placed 

 one upon the other, having articular surfaces between each one. 

 These are called the cuneiform bones of the hock. Immediately 

 behind these three small bones we have what is termed the cuboid 

 bone. This bone also articulates with the cuneiform bones, help- 

 ing to form the articular surface of the hock. The lower articular 

 surfaces help to give a small amount of motion to the joint. This 

 joint is the seat of the disease termed spavin. 



Fetlock, Pastern and Coffin Joints are similar to those in 



front leg. 



In speaking of ligaments, there is another very important 

 one to mention which is called the ligamentum nucha, which 

 supports the head when the muscles are at rest. This extends 

 from the pole of the head backwards under the mane and is 

 attached to the spine of the dorsal vertebrae or, commonly called, 

 the withers of the horse. This ligament is chiefly made up of 

 fibro elastic tissue, and will stretch much the same as a piece of 

 elastic. 



