Osteoarthritis (OA): Joint and Connective Tissue Diseases

Osteoarthritis (OA)

• Also known as "wear-and-tear" arthritis, occurring due to aging and joint overuse
• Most commonly affects weight-bearing joints
• Causes:
  • Damage or breakdown of cartilage between bones
  • Joint injury
  • Age
  • Gender (women > men)
  • Obesity
  • Genetics
• Symptoms:
  • Pain/aching
  • Stiffness
  • Decreased flexibility
  • Swelling
• Diagnosis:
  • Physical examination
  • Imaging tests (X-ray, MRI)
  • Lab tests (blood, synovial fluid)
• Pathophysiology:
  • Progressive loss of articular cartilage and remodelling of the underlying bone
  • Involves degradation of cartilage and remodelling of bone due to an active response of chondrocytes
• Treatment:
  • No specific cure, but its effect can be reduced
  • Control pain
  • Maintain or improve joint function
  • Maintain a normal body weight
  • Achieve an overall healthy lifestyle

Gout

• Type of inflammatory arthritis
• Caused by a robust inflammatory response to uric acid crystals
• Occurs in hyperuricemia (high uric acid levels in the blood)
• Causes:
  • Accumulation of urate crystals in joints
  • Diet (meat, seafood, beverages, and alcohol)
  • Obesity
  • Medical conditions (certain diseases increase risk of gout)
  • Certain medications (thiazide diuretics for hypertension)
  • Family history of gout
  • Age and sex (more common in males)
  • Recent surgery or trauma
• Symptoms:
  • Intense joint pain
  • Inflammation and redness
  • Limited range of motion
• Pathophysiology:
  • Liver produces uric acid, which is eliminated through kidneys
  • High levels of uric acid in blood lead to hyperuricemia
  • Uric acid crystals form in joints, causing inflammation and pain
• Diagnosis:
  • Joint fluid test
  • Blood test (measure level of uric acid and creatinine)
  • X-ray imaging
  • Ultrasound
  • Dual energy CT scan
• Treatment:
  • Medications for pain and inflammation (Colchicine, Corticosteroids, NSAIDs)
  • Medications for lowering uric acid levels (Allopurinol, Febuxostat)
  • Lifestyle changes (limit purine-rich foods, avoid sugar, lose weight, consider pineapple)

Soft Tissue Tumors

• 3 types of soft tissue tumors: benign, intermediate, and malignant
• Benign tumors:
  • Do not invade nearby tissue
  • Do not spread to other parts of the body
  • Examples: lipomas, neurofibroma, schwannomas
• Intermediate tumors:
  • May grow and invade nearby tissues and organs
  • May not spread to distant sites
  • Examples: dermatofibrosarcoma protuberans, fibromatosis
• Malignant tumors:
  • Can spread to other parts of the body
  • Examples: soft tissue sarcomas (e.g. angiosarcoma, liposarcoma, fibrosarcoma)

Soft Tissue Sarcomas

• Can develop in soft tissues like fat, muscle, nerves, fibrous tissues, blood vessels, or deep skin tissues
• Can occur in any part of the body, but most common in arms and legs
• Examples:
  • Angiosarcoma: malignant neoplasm in vessels, showing signs of hemorrhage and necrosis
  • Liposarcoma: rare type of cancer that begins in fat cells
  • Fibrosarcoma: rare type of cancer that affects fibroblasts, responsible for creating fibrous tissue