Tutorial 3 Flashcards
What is the most common type of joint disease?
Osteoarthritis (OA)
OA is characterized as a wear and tear disease with a strong association to age.
List the key components of a normal joint.
- Cartilage
- Synovium (synovial membrane)
- Supporting ligaments & joint capsule
What is the major proteoglycan in articular cartilage?
Aggrecan
Aggrecan provides a hydrated gel structure that gives cartilage load-bearing properties.
What are the pathological changes in osteoarthritis morphology?
- Fibrillation of cartilage
- Eburnation
- Sclerosis
- Subchondral Cysts
- Osteophytes
What is fibrillation of cartilage?
Early proliferation of chondrocytes followed by their death, leading to dehydration and breakdown of cartilage.
Define eburnation in the context of osteoarthritis.
Bone that is polished by the grinding action of bone on bone due to cartilage loss.
What happens to bone density in osteoarthritis?
Sclerosis occurs, where bone below the area of cartilage loss becomes more dense.
What are subchondral cysts?
Fluid-filled spaces that form following cartilage loss, becoming surrounded by a fibrous capsule.
What are osteophytes?
Mushroom-shaped bony outgrowths that develop at the margins of articulating bone.
What is the primary treatment approach for osteoarthritis?
Management of pain, physiotherapy, activity modification, and possibly arthroplasty in severe cases.
What type of disease is rheumatoid arthritis?
A systemic autoimmune disease affecting joints, leading to chronic inflammatory polyarthritis.
Who is more commonly affected by rheumatoid arthritis?
Women, at a rate of approximately 3 times more than men.
What are the two main auto-antibodies present in rheumatoid arthritis?
- Rheumatoid Factor (RF)
- Antibodies against Cyclic Citrullinated Peptides (Anti CCPs)
What is the pathogenesis of rheumatoid arthritis?
Initiated by antigen presentation to T helper lymphocytes, leading to cytokine production and inflammation.
What is the ‘pannus’ in rheumatoid arthritis?
A chronically inflamed, thickened synovium that destroys cartilage and bone.
What are the local complications of rheumatoid arthritis?
- Joint instability and deformity
- Erosion of cartilage and bone
- Ankylosis
What systemic symptoms are associated with rheumatoid arthritis?
- Anemia of chronic inflammation
- Fatigue
- Loss of appetite
- High CRP & acute phase proteins
- Intermittent fever
- Weight loss
What typical hand deformities are seen in rheumatoid arthritis?
Radial deviation of the wrist and ulnar deviation of the fingers.
What is the primary goal in the treatment of rheumatoid arthritis?
Control of pain and prevention of joint destruction and deformity.
Fill in the blank: The inflammatory cells in rheumatoid arthritis produce cytokines that stimulate the proliferation of _______.
[fibroblasts, synovial cells, and chondroblasts]
True or False: Rheumatoid arthritis is solely due to genetic factors.
False
Both genetic and environmental factors contribute to the development of RA.
What role does smoking play in the development of rheumatoid arthritis?
It promotes citrullination of self proteins, potentially triggering the disease.
What are MCPs?
MCPs (metacarpophalangeal joints)
What are PIPs?
PIPs (proximal interphalangeal joints)
What is the aim of treatment for rheumatoid arthritis?
Control of Pain, Early treatment to prevent joint destruction, Active monitoring of disease progress, Prevention of disease complications, Improving patient’s quality of life
What are common treatments for RA?
- Pain relief (NSAIDs)
- Physiotherapy
- Immunosuppression
- Steroids
- Disease-Modifying Anti-Rheumatic Drugs (DMARDs)
- Methotrexate
- Other
What is osteomyelitis?
Inflammation of the bone marrow
What usually causes pyogenic osteomyelitis?
Usually caused by pyogenic (pus forming) bacterial infection
Which bacterium causes 80-90% of pyogenic osteomyelitis cases?
Staphylococcus aureus
How do organisms gain entry into the bone in osteomyelitis?
- Haematogenous dissemination
- Spread from an adjacent site
- Trauma
- Surgical (Iatrogenic)
What happens to the blood supply in pyogenic osteomyelitis?
Increasing pressure compresses the blood supply leading to necrosis of medullary bone
What is a sequestrum?
Dead bone resulting from pressure within the marrow cavity or loss of blood supply
What is involucrum?
New bone laid down beneath the periosteum
What is the treatment for osteomyelitis?
- Antibiotics according to culture and sensitivity
- Surgical debridement if no improvement in 24-48 hours
What is gout?
Arthritis initiated by deposition of urate crystals within and around joints
What condition leads to hyperuricemia?
Excess uric acid in tissues and plasma
What is primary gout?
Gout of unknown cause in ~90% of cases
What is secondary gout caused by?
- Increased production of uric acid
- Decreased excretion of uric acid
What triggers an acute inflammatory reaction in acute gout?
Precipitation of monosodium urate (MSU) crystals within the joints
Where do MSU crystals commonly precipitate?
In peripheral joints where synovial fluid is a poor solvent and temperature is low
What is chronic tophaceous gout?
Condition where aggregates of urate crystals deposit within the synovial membrane
What are tophi?
Aggregates of urate crystals
What is the treatment for gout?
- NSAIDs
- Colchicine
- Low dose steroids
- Hydration
- Medical assessment to reduce risk factors
What is septic arthritis?
Infection of the joint leading to acute inflammation and pus formation
What is the most common causative organism of septic arthritis?
Staphylococcus aureus
What are the entry routes for organisms in septic arthritis?
- Bacteraemia
- Trauma
- Surgery (Iatrogenic)
What is the classic presentation of hematogenous septic arthritis?
Young child with fever and severe localized joint pain, swelling, and marked limitation in range of movement
What is the treatment for septic arthritis?
- Surgical drainage and irrigation of the affected joint
- Systemic antibiotic therapy
