Part IV Joints

A. Structural Classes of Joints 1. Fibrous joints Generally immovable 2. Cartilaginous joints Immovable or slightly moveable 3. Synovial joints Freely moveable with lubricating fluid

B. Fibrous Joints Bones united by fibrous tissue Examples 1. Sutures Example: skull bones 2. Syndesmoses Allows more movement than sutures Example: distal end of tibia and fibula Figure 5.27a–b

C. Cartilaginous Joints Bones connected by cartilage Examples 1. symphysis pubic symphysis intervertebral joints 2. synchondrosis sternum and 1st rib Figure 5.27d–e

Synovial Joints Most common type of joint Articulating bones are separated by a joint cavity Synovial fluid is found in the joint cavity Figure 5.24f–h

Features of Synovial Joints Articular cartilage (hyaline cartilage) covers the ends of bones Meniscus is a disk of fibrocartilage between articulating surfaces in the knee Joint surfaces are enclosed by a fibrous articular capsule Have a joint cavity filled with synovial fluid Ligaments reinforce the joint

Synovial Joint - Knee

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

The Synovial Joint Figure 5.28

Types of Synovial Joints Based on Shape Figure 5.29a–c

D. Synovial Joints 1. plane/gliding joint – carpal-carpal; tarsal-tarsal; sternum-ribs (2-7) 2. hinge joint – elbow (ulna-humerus); knee (femur-tibia); phalanx-phalanx 3. pivot joint – ulna-radius

Types of Synovial Joints Based on Shape Figure 5.29d–f

D. Synovial Joints 4. condyloid –metacarpal-phalanx 5. saddle – thumb (carpal-metacarpal) 6. ball and socket – shoulder (humerus-scapula) , hip (femur-coxal)

Chapter 5 Vocabulary axial skeleton appendicular skeleton articular cartilage epiphyseal plate meatus sinus foramen sutures thoracic cage pectoral girdle pelvic girdle pubic symphysis osteoarthritis rheumatoid arthritis osteoporosis

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

Clinical Forms of Arthritis Osteoarthritis Most common chronic arthritis that affects the articular cartilage typically in the aged. Probably related to normal aging processes; “wear and tear” arthritis

Osteoarthritis

Clinical Forms of Arthritis Rheumatoid arthritis An autoimmune disease – the immune system attacks the joints Symptoms begin with bilateral inflammation of certain joints such as wrist, fingers, ankles, feet Often leads to deformities Gouty Arthritis Inflammation of joints is caused by a deposition of urate crystals from the blood Can usually be controlled with diet

Rheumatoid arthritis

Rheumatoid arthritis

Bone disorders Osteoporosis Bone-thinning disease that leads to fractures Afflicts half of women over 65 and 20% of men over 70 Makes bone so fragile that a hug or sneeze can cause bones to fracture Bones of spine and neck of femur (hip) are particularly affected Causes hunched-over posture (kyphosis) known as dowager’s hump

Osteoporosis

Osteoporosis

Gouty Arthritis