A "typical" synovial joint is one which has parts common to all
of the synovial joints. In a sense, it is imaginary. It is not actually a specific
synovial joint. It is a composite. It is illustrated in figure 4-2. The
"typical" synovial joint has the following parts:
a. Bones. Bones are the levers of motion. They are the site of
attachment for skeletal muscles.
b. Articular Cartilages. The "contact" points of the
bones are usually covered with a layer of lubricated cartilage. Where these cartilages
end, the synovial membranes begin. Cartilages provide a smooth surface to reduce friction.
c. Synovial Membrane, Space, and Fluid.
(1) Synovial membrane. The synovial membrane lines the inner surface of
the capsule. It secretes synovial fluid into the synovial space.
(2) Synovial space. Figure 4-2 exaggerates the amount of space between the
bones. The space within the capsule allows movement.
(3) Synovial fluid. Synovial fluid is a colorless, viscous fluid similar
in consistency to raw egg white. It lubricates the articulation.
d. Capsule. The "typical" synovial articulation is
surrounded by a sleeve of dense FCT known as the capsule. The capsule encloses the
articulation.
e. Ligaments. Primarily, ligaments hold bones together. Ligaments
also may help restrain motion in certain directions and stabilize the articulation.
f. Muscles. Skeletal muscles apply the forces to produce a given
motion.
NOTE: See table 4-1 for a
summary of the structures in a "typical" synovial articulation, the tissues
composing each structure, and the actions attributed to each structure.
Primary Content Providers: The U. S. Army, The
U.S. Navy
Ancillary Content and Online Version: David L. Heiserman
Publisher: SweetHaven Publishing Services
