Bone disease Flashcards
Most common places for osteoporotic fractures?
Neck of femur (hip), wrist (Colles’), vertebral
Osteopororis definition?
Metabolic bone disease:
Low bone mass with micro architectural deterioration of bone tissue > fragility of skeleton > incr in fracture risk
What is the most important role of osteocytes?
Maintaining bone mass
What stimulates osteoclastic and osteoblastic activity aka bone turnover?
Movement
Why is osteoporosis more common in women than men?
Oestrogen deficiency (as occurs with menopause) > bone loss
Where does bone coupling occur?
Howship’s lacunae, never on flat bone
Why does oestrogen deficiency > incr osteoclastic activity?
Incr stimulation of RANKL pathway because decr oestrogen = decr OPG (natural inhibitor of RANKL pathway).
What is rate of bone loss in first 5 years in post menopausal women? When does osteoporosis start to present?
3% per year
20 years post menopause
How much bone mass can women lose post menopause
40%
What is the most significant factor when determining whether someone will be at risk of fracture after bone mass reduction?
Peak bone mass
How can you treat osteoarthritis?
Replacement of the joint
6 categories of joint disease?
Degenerative (osteoarthritis) Inflammatory/autoimmune (RA, spondiloarthropathies) Metabolic (gout) Trauma Infection Neoplastm
What is always important to consider when thinking about joint disease?
Systemic autoimmune?
What is osteoarthritis?
Degenrative changes in the articular cartilage
Followed by reactive change in the subchondral bone and the synovium
What is the gender split in osteoarthritis? How does age affect epidemiology?
Equal, exponential increase after age of 50.
How does osteoarthritis appear on X-rays? (4) mem aid. + 1 extra
What order do they appear in re. severity?
In order of severity
Loss of articular space
Osteophytes (don’t correspond to stage really)
Subchondral sclerosis
Subchondral cysts
Occasionally also get fragmentation of osteochondral compression (loose bodies) - quite rare
How does RA differ from osteoarthritis.
Inflammation of the synovial capsule.
Inflammation covers the articular surface, suffocates it > degeneration
Which joints tend to be affected in osteoarthritis?
Women are also more prone to get arthritis where?
Weight bearing joints: knee, hip, spinal
Small joints: hands and feet
What is the percentage split between primary and secondary osteoarthritis?
90 : 10 %
Obesity, congenital deformities and obesity can all increase risk of OA, when does each of the following also increase risk?
- oestrogen status
- bone mineral density
Low oestrogen
High bone density
Which therapeutic interventions slow down the onset of OA?
None
What hand deformities are seen in OA?
How do these differ from RA?
Bouchard’s nodes, Heberden’s nodes (PIP and DIP joints), squaring at the base of the thumb.
MCP joints are spared
Where in the body is bony malalignment particularly common in OA? What does this cause?
Knees. Knock knees (genu valgum), bow legs (genu varum)
Other than the hand, where else can bony deformities develop in advance OA?
Knee (due to new bone formation)
Which of the following is the most common presentation of OA in the knee joint?
- crepitus
- stiffness
- effusion
Crepitus
In OA, what would you expect the following test results to show?
- CRP
- ESR
- RF
- anti CCP antibody
Normal
Normal
Negative
Negative
What is the cause of primary osteoarthritis?
Proteoglycan and collagen II changes
List some causes of secondary arthritis (4)?
Deformity , RA, metabolic disease, crystal deposition disease?
What is an osteophyte? What is their effect re. joint disease?
New bone formation at edge of joint
Can compress nerves –> pain
