Chapter 5 The Skeletal System: Pathology Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 5 The Skeletal System: Pathology Slides 5.45 – 5.55 Lecture Slides in PowerPoint by Jerry L. Cook Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings

Bone Fractures A break in a bone Types of bone fractures Closed (simple) fracture – break that does not penetrate the skin Open (compound) fracture – broken bone penetrates through the skin

Common Types of Fractures Table 5.2

Comminuted Fracture

Compression Fracture

Depression Fracture

Impacted Fracture

Spiral Fracture

Greenstick Fracture

Bone Fractures Bone fractures are treated by reduction and immobilization Reduction is the realignment of the bone ends Two types of reduction: Closed reduction: bone ends are coaxed back into their normal position by the physician’s hands Open reduction: surgery is performed and the bone ends are secured together with pins or wires Immobilization occurs with a cast or traction to allow the healing process to begin (6 to 8 weeks for a simple fracture)

Stages in the Healing of a Bone Fracture Figure 5.5

Repair of Bone Fractures Hematoma (blood-filled swelling) is formed (blood vessels are ruptured when the bone breaks) Break is splinted by a fibrocartilage callus (new capillaries, connective tissue form for repair) Fibrocartilage callus is replaced by a bony callus as osteoblasts and osteoclasts migrate to the area Bony callus is remodeled to form a permanent patch of bone

Diseases of the Vertebral Column Scoliosis Lordosis Kyphosis

The Vertebral Column Vertebrae separated by intervertebral discs The spine has a normal curvature Each vertebrae is given a name according to its location Figure 5.14

Diseases of the Vertebral Column Scoliosis – an abnormal lateral curvature of the spine

Diseases of the Vertebral Column Lordosis – an exaggerated curvature of the lumbar spine

Diseases of the Vertebral Column Kyphosis – an exaggerated curvature of the thoracic spine (usually superior thoracic spine)

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

Injuries to Joints Dislocation: displacement of a bone from its joint Strain: less serious than sprain; a stretched or partially torn muscle Sprain: forcible wrenching or twisting of a joint that stretches or tears its ligaments but does not dislocate the bones.

Clinical Forms of Arthritis Osteoarthritis Most common chronic arthritis Probably related to normal aging processes Articular cartilage gets worn out. Exposed bone thickens, forming bone spurs. Bone spurs protrude into joint cavity, impairing mobility. Typically affects fingers, cervical and lumbar spine, knees, and hips. Not usually bilateral

Areas commonly affected by osteoarthritis:

Clinical Forms of Arthritis Rheumatoid arthritis An autoimmune disease – the immune system attacks the joints. Inflammation of the synovial membranes, synovial fluid and white blood cells accumulate in joint cavity. WBC’s produce pannus which clings to and erodes articular cartilage. Scar tissue forms between bones, possibly replaced by bone (ankylosis). Symptoms begin with bilateral inflammation of certain joints (particularly the fingers, wrists, ankles, and feet) Usually begins around 40-50 years old, but can develop at any age Often leads to deformities

Rheumatoid Arthritis

Rheumatoid Arthritis

Aging Bones Osteoporosis: porous bones; bone- thinning disease Bone resorption outpaces bone deposition Bone mass depleted Fractures more common Shrinkage of vertebrae