I. CLASSIFICATION OF JOINTS
articulations = joints
    * def: a place where two or more bones meet

    -- Two ways to classify joints:
        1) structure

            a) Fibrous Joints:
                * dense regular CT ( fibrous CT) connects bones

           b) Cartilaginous Joints:
                * cartilage binds the bone

            c) Synovial Joints:
                * ligaments support articulating bones
                * bone ends separated by a joint cavity

       2) Movement
            a) Synarthrosis: immovable joint
            b) Amphiarthrosis: slightly moveable
            c) Diarthrosis: freely moveable

-- in joints, there's an inverse relationship between mobility and stability
(the more mobile a joint, the less stable it is)

II. FIBROUS JOINTS
    A. Suture: dense regular CT binds bones
        * immovable joint (synarthrosis)
 

    B. Syndesmosis: bones held together by interosseous ligaments
        * slight movement (amphiarthrosis)
 

    C. Gomphosis: root of tooth attached to jaw by periodontal ligaments
        * synarthrosis
 

III. CARTILAGINOUS JOINTS
    A. Synchondrosis: bones connected by hyaline cartilage
        * synarthrosis

   B. Symphysis: bones connected by fibrocartilage
        * amphiarthrosis
 

IV. SYNOVIAL JOINTS
    --  diarthroses

    A. Structure
        -- ligaments

        -- articular (joint) capsule

        -- synovial membrane
            * makes synovial fluid

        -- joint cavity

        -- ends of bones lined w/articular cartilage
 

    B. Kinds of Synovial Joints
        1) Planar (Gliding):
            * side-to-side movements

2) Hinge:
      * permits bending in only one plane
      * most common kind of synovial joint
 

        3) Pivot:
            * permits rotational movement about a longitudinal axis
       
 

        4) Condyloid (Ellipsoidal):
            * biaxial movements (movements in 2 planes)
 

        5) Saddle:
            * wide range of movement
 

        6) Ball-and-Socket:
            * provides greatest range of movement

REVIEW THE DIFFERENT KINDS OF JOINTS USING
THE  ARTICULATIONS MEMORY MATRIX .
 

V. MOVEMENTS AT SYNOVIAL JOINTS
    A. Flexion: decreases joint angle in A-P plane

        * special kinds of flexion at ankle joint:
            1) dorsiflexion: dorsum (top) of foot is elevated
            2) plantar flexion: bringing foot and toes closer to back of leg

    B. Extension: increases joint angle in A-P plane

    C. Abduction: body part moved away from midline of the body, in a lateral direction

    D. Adduction: body part moved toward the midline of the body, in a medial direction

    E. Rotation: movement of a body part around its own axis

        * special kinds of rotation of forearm:
            1) supination: palm of hand facing anteriorly
            2) pronation: palm facing posteriorly

F. Circumduction: circular, conelike movement of a body segment

G. Inversion: movement of the sole of the foot inward or medially

H. Eversion: movement of the sole of the foot outward or laterally


I. Depression: inferior movement of a body part

J. Elevation: superior movement of a body part

K. Protraction: movement of a body part anteriorly, in a horizontal plane

L. Retraction: movement of a body part posteriorly, in a horizontal plane

This type of synovial joint allows for movement in only one plane.  An example is the elbow joint.

a.  pivot

b.  saddle

c.  ball and socket

d.  condyloid

e.  hinge
 

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