Joints A joint, or articulation, is the place where

two bones come together.

Fibrous- Immovable; connect bones, no movement. (skull and pelvis).

Cartilaginous- slightly movable; bones are attached by cartilage, a little movement (spine or ribs).

Synovial- freely movable; much more movement than cartilaginous joints. Cavities between bones are filled with synovial fluid. This fluid helps lubricate and protect the bones.

The Synovial JointThe Synovial Joint

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Figure 5.28

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COMPOSITION OF JOINTSCOMPOSITION OF JOINTS

• Ligament - connects bone to bone

• Tendon - connects muscle to bone

• Bursa - fluid filled sac that allows bones to move easily over others

• Cartilage – connective tissue that cushions the joint at end of bones and between bones

Types of Synovial Joints Based Types of Synovial Joints Based on Shapeon Shape

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Hinge Joint A hinge joint allows extension and

retraction of an appendage. They are found in the elbow and knee.

A ball and socket joint allows for radial movement in almost any direction. They are found in the hips and shoulders

Ball and Socket Joint

In a gliding or plane joint bones slide past each other. Mid-carpal and mid-tarsal joints are gliding joints. (Hands, Feet)

Gliding Joint

This type of joint allows rotary movement. The joint between the atlas and the axis in the neck and the joint in the forearm are pivot joints.

Pivot Joint

Common Disordersof the Skeletal

System

Osteoporosis porous bone that breaks easily and are

weaker loss of minerals, especially calcium Common in spine, hips and wrists

Arthritis

Osteoarthritis- cartilage wears away○ Usually affects weight

bearing joints (knees, hips, vertebrae and fingers)

○ Wear and tear over timeRheumatoid arthritis-

synovial membrane inflames ○ Autoimmune disease○ Can occur at any age

inflammation of the joints

Bursitis inflammation of the bursa (fluid filled sac

surrounding the joint) A bursa can become inflamed from injury,

infection, or due to an underlying rheumatic condition

localized pain or swelling, tenderness, and pain with motion of the tissues in the affected area.

Tendonitis inflammation of the tendon Causes:

Sudden increase in useOveruse or repetitive movementUnderlying biomechanical issue

Sprains and Strains Sprain

stretched or torn ligamentfall, twist or hit can move a joint out of placemild to severe

Strainstretched or torn muscle or tendonmay occur suddenly or over time