Joints Articulations of bones Functions of joints Hold

Joints · Articulations of bones · Functions of joints · Hold bones together · Allow for mobility · Ways joints are classified · Functionally · Structurally Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 43

Functional Classification of Joints · Synarthroses – immovable joints · Amphiarthroses – slightly moveable joints · Diarthroses – freely moveable joints Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 44

Structural Classification of Joints · Fibrous joints · Generally immovable · Cartilaginous joints · Immovable or slightly moveable · Synovial joints · Freely moveable Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 45

Fibrous Joints · Bones united by fibrous tissue – synarthrosis or largely immovable. Figure 5. 27 d, e Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 46

Cartilaginous Joints – mostly amphiarthrosis · Bones connected by cartilage · Examples · Pubic symphysis · Intervertebral joints Figure 5. 27 b, c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 47

Synovial Joints · Articulating bones are separated by a joint cavity · Synovial fluid is found in the joint cavity Figure 5. 27 f–h Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 48

Features of Synovial Joints. Diarthroses · Articular cartilage (hyaline cartilage) covers the ends of bones · Joint surfaces are enclosed by a fibrous articular capsule · Have a joint cavity filled with synovial fluid · Ligaments reinforce the joint Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 49

Structures Associated with the Synovial Joint · Bursae – flattened fibrous sacs · Lined with synovial membranes · Filled with synovial fluid · Not actually part of the joint · Tendon sheath · Elongated bursa that wraps around a tendon Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 50

The Synovial Joint Figure 5. 28 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 51

Types of Synovial Joints Based on Shape Figure 5. 29 a–c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide

Types of Synovial Joints Based on Shape Figure 5. 29 d–f Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide

Inflammatory Conditions Associated with Joints · Bursitis – inflammation of a bursa usually caused by a blow or friction · Tendonitis – inflammation of tendon sheaths · Arthritis – inflammatory or degenerative diseases of joints · Over 100 different types · The most widespread crippling disease in the United States Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 5. 53

Clinical Forms of Arthritis · Osteoarthritis · Most common chronic arthritis · Probably related to normal aging processes · Rheumatoid arthritis · An autoimmune disease – the immune system attacks the joints · Symptoms begin with bilateral inflammation of certain joints · Often leads to deformities Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide

The Skeletal System u Synovial joints ¶ components F articulating bones F articular (joint) capsule F articular cartilage F synovial membrane F synovial fluid · movements allowed u Other joint types

The Skeletal System • Age-related changes o loss of calcium from bone matrix § collagen fibers replacement slow with age o result is change in ratio leading to brittle bones o articular cartilages wear thin and are not replaced o fibrocartilage changes resulting in disc problems

The Skeletal System Age-related dysfunctions ¶ bursitis F What is a bursa? F Where are they found? F What causes bursitis? F How is it treated?

The Skeletal System u Age-related dysfunctions · arthritis F To what does the term arthritis refer? F What parts of a joint are involved? F What is the response of the joint? F There are three main types: ä osteoarthritis ä rheumatoid arthritis ä gouty arthritis

The Skeletal System u Age-related dysfunctions â osteoarthritis (degenerative joint disease) Ø 90% of people >40 years have it Øarticular cartilages degenerate Ø bony spurs develop Ø locations Ø possible causes

The Skeletal System u Age-related dysfunctions â rheumatoid arthritis ü not necessarily old age disease ü bilateral effects üinitial insult is inflammation of synovial membrane üscarring occurs with growth of a pannus üWhat can be done?

The Skeletal System u Age-related dysfunctions â gouty arthritis vexcessive blood uric acid, leading to precipitation as sodium uric acid crystals vinflammatory response usually begins in big toe vtends to be chronic vcan lead to tophus formation v. What can be done?

The Skeletal System u Age-related dysfunctions ¸ osteoporosis F bone remodeling gone bad (? ) F women vs. men F vertebrae most affected F suspected factors: ä calcium ä vitamin D ä estrogen ä exercise

The Skeletal System u Age-related dysfunctions ¸ osteoporosis F treatments estrogen replacement calcitonin therapy exercise

Clinical Forms of Arthritis · Gouty Arthritis · Inflammation of joints is caused by a deposition of uric acid crystals from the blood · Can usually be controlled with diet Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide