CHAPTER II. 
CONSIDERATION OF JOINTS. 
THE various structures which enter into the formation 
of joints are the extremities of bone, Hgaments, car- 
tilage, and sometimes muscles which help to support 
the joint. All articular joints are supplied with a 
synovial membrane, which secretes the synovia or joint oil 
for lubricating the joint. 
1. Cartilage. Cartilage, or what is familiarly called 
gristle, is of two kinds, viz. : articular and fibrous. The 
fibrous is not of much importance and does not need much 
consideration ; it is found in various parts of the body. The 
articular cartilage, which covers over the ends of bones where 
they form a joint, is of more importance. 
2. Ligaments. — Ligaments are strong fibrous bands found 
principally around joints. They are of two kinds, capsular 
and binding. A capsular ligament is a thii^ membrane, at- 
tached around the end of each bone, which helps to form a 
joint, and is, as it were, air-tight. These ligaments serve the 
purpose of keeping the joint oil from escaping and assist in 
holding the bones together. The synovia membrane is situ- 
ated on the inside lining of this ligament. It secretes the 
joint oil. Binding ligaments are generally found on each 
side of the joint and are very strong bands of fibrous tissue. 
They serve the purpose of holding the bones of the joint 
firmly together. 
There is a very important ligament called the ligamentum 
nucha. It supports the head when the muscles are at rest 
and extends from the pole of the head backward under the 
mane and is here 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. This ligament can be 
plainly seen in p'late I., although not specially marked. In 
operating on a case of poll evil there is always a danger of 
cutting it oflf unless the operator be careful. 
