Osteoporosis

Question 1

What is osteoporosis?

Answer 1

Osteoporosis is a complex skeletal disease characterised by low bone density and micro-architectural defects in bone tissue, resulting in increased bone fragility and susceptibility to fracture.

Question 2

What are the risk factors for osteoporosis?

Answer 2

• Prior fragility fracture
• Female
• White
• Older age (>50 for women and >65 for men)
• Low BMI
• Vitamin D deficiency
• Post menopause
• Smoking
• Materal history of hip fracture

Question 3

What are the symptoms of osteoporosis?

Answer 3

• Back pain
• Impaired vision

Question 4

What are the signs of osteoporosis?

Answer 4

• Kyphosis
• Impaired gait, imbalance and lower extremity weakness

Question 5

Briefly describe kyphosis

Answer 5

Abnormally excessive convex curvature of the spine as it occurs in the thoracic and sacral regions.

Question 6

What investigations should be ordered for osteoporosis?

Answer 6

• Dual-energy X-ray absorptiometry (DXA)
• Fracture risk assessment tool (FRAX)
• X-ray
• Quantitative CT

Question 7

Why investigate dual-energy x-ray absorptiometry (DXA)? And what may this show?

Answer 7

• DXA is considered the gold standard for measurement of bone density.
• T-score of ≤-2.5 indicates osteoporosis; T-score ≤-2.5 with fragility fracture(s) indicates severe (or established) osteoporosis.

Question 8

Why investigate fracture risk assessment risk (FRAX)? And what may this show?

Answer 8

• FRAX was developed by the World Health Organization to assess fracture risk. FRAX integrates clinical risk factors for fracture and bone mineral density scores at the femoral neck to calculate a 10-year fracture probability for men and women.
• Interpretation of FRAX scores varies depending on location.

Question 9

Why investigate using x-ray? And what may this show?

Answer 9

• X-ray may reveal osteopenia and/or fractures (e.g., vertebral fractures), but does not diagnose osteoporosis.
• May reveal osteopenia and/or fractures (e.g., vertebral fractures).

Question 10

Why investigate using quantitative CT? And what may this show?

Answer 10

• Alternative modality if dual-energy x-ray absorptiometry not available.
• Reduced trabecular bone density.

Question 11

Briefly describe the treatment for osteoporosis

Answer 11

• The main goal of treatment is prevention of fractures, particularly hip, vertebral, and radial fractures. The approach to treatment is population specific, but calcium and vitamin D supplementation is pertinent to all people at risk of and with osteoporosis.
• Bisphosphonates are the first-line treatment for postmenopausal women with prior hip or vertebral fractures and/or dual-energy x-ray absorptiometry (DXA) T-score of ≤-2.5

Question 13

What is the role of bisphosphonates in osteoporosis?

Give examples of bisphosphonates used in osteoporosis

Answer 13

• Bisphosphonates are the first-line treatment for postmenopausal women with prior hip or vertebral fractures and/or dual-energy x-ray absorptiometry (DXA) T-score of ≤-2.5.
• Alendronic acid, ibandronic acid, risedronate and zoledronic acid.

Question 14

What is the role of calcium and vitamin D supplementation in osteoporosis?

Give examples of calcium and vitamin D supplements used in osteoporosis

Answer 14

• Diet supplementation with calcium and vitamin D is intended to prevent osteoporosis and reduce the incidence of fracture.
• Ergocalciferol and calcium.

Question 15

What complications are associated with osteoporosis?

Answer 15

• Hip fractures
• Rib fractures
• Wrist factures
• Chronic pain syndrome (CPS)

Question 16

What differentials should be considered for osteoporosis?

Answer 16

• Multiple myeloma
• Osteomalacia
• Chronic kidney disease- bone and mineral disorder

Question 17

How does osteoporosis and multiple myeloma differ?

Answer 17

• Differentiating signs and symptoms: bone pain and symptoms of anaemia and renal failure.
• Differentiating investigations: urine electrophoresis reveals Bence Jones proteinuria; serum electrophoresis reveals monoclonal gammopathy.

Question 18

How does osteoporosis and osteomalacia differ?

Answer 18

• Differentiating signs and symptoms:difficult to differentiate clinically from osteoporosis.
• Differentiating investigations: PTH levels elevated; bone biopsy standard for confirmation of poor mineralisation.

Question 19

How does osteoporosis and chronic kidney disease-bone and mineral disorder differ?

Answer 19

• Differentiating signs and symptoms: difficult to differentiate clinically from osteoporosis. Patients may have known history of renal failure, and may present with bone pain and diminished muscular strength.
• Differentiating investigations: serum creatinine and PTH elevated.

Question 20

Briefly describe the T-scoring system used in osteoporosis

Answer 20

A T-score is the number of standard deviations above or below the bone mineral density mean for young, healthy white women.

A World Health Organization study group proposed four categories for T-scores:

• Normal: T-score ≥-1
• Osteopenia: T-score -2.5
• Osteoporosis: T-score of ≤-2.5
• Severe (or established) osteoporosis: T-score ≤-2.5 with fragility fracture(s).