Arthritis and Skeletal System Review

Arthritis Definition & Types

• Definition: Refers broadly to joint disease, encompassing over 100 different types.

• Two Big Categories:

  • Osteoarthritis (OA): Also known as "wear and tear" arthritis. Characterized by cartilage breakdown and degeneration over time.

  • Inflammatory Arthritis: Caused by immune system issues. Examples include rheumatoid arthritis, lupus, and psoriatic arthritis.

• Other Specific Types:

  • Gout: Caused by crystal accumulation, specifically uric acid.

  • Ankylosing Spondylitis.

  • Juvenile Arthritis: Onset occurs before the age of 16.

Symptoms & Signs

• Common features across many forms:

  • Joint pain.

  • Stiffness or reduced range of motion.

  • Swelling, warmth, and redness around joints (particularly characteristic of inflammatory types).

• Distinctions in pain/stiffness patterns:

  • In OA, pain is typically aggravated by activity.

  • In inflammatory arthritis, stiffness is more pronounced after rest or inactivity, especially morning stiffness.

Causes & Risk Factors

• Causes by Type:

  • OA: Associated with aging, long-term joint use, and previous joint injuries.

  • Inflammatory Arthritis: Rooted in immune system dysfunction; can sometimes be triggered by infections or genetic predisposition.

  • Gout: Caused by high levels of uric acid in the blood.

• General Risk Factors:

  • Age: Older individuals are more likely to develop arthritis.

  • Sex/Gender: Some types, such as rheumatoid arthritis, are more prevalent in females.

  • Obesity: Adds mechanical stress to joints and can contribute to an inflammatory component.

  • Family History / Genetics.

  • Joint Injuries or physically demanding use of joints.

  • Smoking Tobacco.

Diagnosis

• Clinical History & Physical Exam: Involves assessing pain, stiffness, and examining joint motion.

• Imaging: Techniques such as X-ray, ultrasound, CT, and MRI are used to evaluate joint damage, inflammation, and bone changes.

• Blood Tests: Conducted to check for conditions like gout (by measuring uric acid levels), autoimmune markers, or signs of infection.

Treatment & Management

• Overall Goal: Since most types have no cure, the focus is on symptom relief, slowing disease progression, and maintaining function.

• Medications:

  • Pain Relief: NSAIDs (Nonsteroidal Anti-Inflammatory Drugs), OTC anti-inflammatories, and acetaminophen.

  • Flare-ups: Corticosteroids, sometimes delivered via injections.

  • Inflammatory Types: Disease-modifying anti-rheumatic drugs (DMARDs) are used for conditions like rheumatoid and psoriatic arthritis.

• Non-Medication Approaches:

  • Physical Therapy (PT) & Occupational Therapy (OT): Aim to maintain range of motion, muscle strength, and overall function.

  • Exercise: Low-impact exercise is generally recommended.

  • Healthy Diet.

• Surgery:

  • Joint Replacement (Arthroplasty): Considered for severe cases where other treatments are insufficient.

  • Joint Fusion: Performed in certain joints (e.g., ankle, spine) in specific circumstances.

Prognosis, Prevention & Living with Arthritis

• Prognosis: Depends on the specific type, severity of the disease, how early treatment is initiated, and how effectively risk factors (e.g., weight, lifestyle) are managed.

• Prevention Strategies:

  • Maintain a healthy weight.

  • Avoid joint injuries.

  • Engage in regular low-impact exercise.

  • Avoid smoking.

• Living with Arthritis:

  • Monitor symptoms and learn to manage flare-ups.

  • Actively engage with healthcare providers by asking questions about the specific type of arthritis, available treatments, necessity of surgery, and follow-up care.

Bone Tissue and Skeletal System / Skeletal System Introductions & Skeleton Structure

Bone Tissue & the Skeletal System (Introduction; typical sections \text{6.1}–\text{6.7})

• Components of Bone Tissue:

  • Cells:

  • Osteoblasts: Responsible for building new bone tissue.

  • Osteocytes: Mature bone cells that maintain the bone matrix.

  • Osteoclasts: Cells that resorb (break down) bone tissue.

  • Matrix:

  • Organic Portion: Primarily composed of collagen fibers and ground substance.

  • Inorganic Minerals: Chiefly hydroxyapatite, along with calcium and phosphate, which impart strength and rigidity to the bone.

• Bone Classification:

  • By Shape: Includes long bones, short bones, flat bones, and irregular bones.

  • By Structure: Differentiated into compact bone (cortical bone) and spongy bone (trabecular bone).

• Bone Growth & Development:

  • Ossification: The process of bone formation, occurring via two main types: intramembranous ossification and endochondral ossification.

  • Growth in Length: Occurs at the epiphyseal plates.

  • Growth in Width: Achieved through appositional growth.

  • Remodeling: Bone is continuously remodeled throughout life, balancing resorption by osteoclasts and deposition by osteoblasts.

• Functions of the Skeletal System:

  • Support: Provides a framework for the body.

  • Protection: Safeguards vital organs.

  • Leverage for Movement: Serves as attachment points for muscles, enabling movement.

  • Mineral Storage: Especially for calcium and phosphorus.

  • Blood Cell Formation: Occurs in the red bone marrow.

  • Energy Storage: In the form of yellow marrow.

Axial Skeleton

• Components:

  • Skull: Comprises the cranium and facial bones.

  • Vertebral Column: Includes cervical, thoracic, and lumbar vertebrae, as well as the sacrum and coccyx.

  • Thoracic Cage: Made up of the ribs and sternum.

  • Hyoid Bone.

• Functions:

  • Protects the brain, spinal cord, and thoracic organs (heart, lungs).

  • Provides attachment sites for ribs and muscles.

  • Supports the body’s vertical axis, facilitating upright posture.

Appendicular Skeleton

• Components:

  • Upper Limbs: Consist of the arm, forearm, and hands, connected to the shoulder girdle (clavicles and scapulae).

  • Lower Limbs: Include the thigh, leg, and feet, connected to the pelvic girdle (hip bones).

• Functions:

  • Movement: Limbs are crucial for locomotion and manipulation of the environment.

  • Support Weight.

  • Leverage for Muscles.

Joints (Introduction)

• Definition: Places where two bones meet, designed to allow movement and provide stability.

• Classification:

  • By Structure (based on material connecting bones and presence of a cavity):

  • Fibrous Joints: Bones held together by fibrous connective tissue; lack a joint cavity (e.g., sutures of the skull).

  • Cartilaginous Joints: Bones connected by cartilage (e.g., intervertebral discs, pubic symphysis).

  • Synovial Joints: Possess a joint cavity, synovial fluid, and articular cartilage; are typically the most movable type.

  • By Function (based on amount of movement permitted):

  • Synarthrosis: Immovable joints.

  • Amphiarthrosis: Slightly movable joints.

  • Diarthrosis: Freely movable joints.

• Synovial Joint Features:

  • Articular cartilage, joint cavity, synovial membrane, synovial fluid, ligaments.

  • May also include bursae and tendons.

  • Types by Shape and Movement Permitted: Examples include hinge, pivot, ball-and-socket, saddle, condyloid, and plane joints.

• Joint Health / Maintenance:

  • Maintaining articular cartilage integrity and adequate synovial fluid lubrication are critical.

  • Joint injuries, inflammation, and degeneration (as seen in arthritis) can significantly impair function.