Osteoporosis and Other Merabolic Bone Disease Evaluation Flashcards
What is the definition of osteoporosis?
Skeletal disorder characterized by compromised bone strength, predisposes to fragility fractures. Diagnosed by fragility fracture, low bone mineral density (BMD), or high FRAX risk score.
What are fragility fractures?
Fractures that occur spontaneously or after minimal trauma, with common sites including vertebrae, hips, and distal radius (Colles’ fracture).
What is the lifetime risk of fragility fractures in women and men?
- 40% in women
- 13% in men
What complications can arise from vertebral fractures?
- Loss of height
- Kyphosis (dowager’s hump)
- Reduced pulmonary function
- 1/3 painful, 2/3 asymptomatic
What are some complications of hip fractures?
- 50% permanent disability
- 20% excess mortality
What risk factors increase the likelihood of osteoporotic fractures?
- Low BMD
- Age above 60
- Previous fragility fracture
- Frequent falls
- Corticosteroid use
What are the fragility fracture criteria for diagnosing osteoporosis?
Presence of a fragility fracture indicates osteoporosis, regardless of BMD.
What T-score indicates osteoporosis in individuals over 50 years old?
T-score ≤ -2.5
What is the T-score for diagnosing osteoporosis in individuals under 50?
Z-score ≤ -2.0
What is the FRAX risk assessment threshold for hip fracture and major osteoporotic fractures?
- 10-year risk ≥3% for hip fracture
- ≥20% for major osteoporotic fractures
What are clinical clues for detecting vertebral fractures?
- Back pain
- Height loss ≥2 inches
- Kyphosis
What is the gold standard for measuring Bone Mineral Density (BMD)?
DXA (Dual Energy X-ray Absorptiometry)
What is the radiation exposure from a DXA scan?
1–3 mSv/site
What age is recommended for BMD measurement in women and men?
- Age ≥65 for women
- Age ≥70 for men
What are indications for BMD measurement?
- Age ≥65 (women), ≥70 (men)
- Estrogen deficiency + risk factor
- Vertebral deformity or fracture
- Primary hyperparathyroidism
- Glucocorticoid therapy
What does the T-score represent in bone densitometry reports?
SDs below/above young normal peak bone mass.
What is the relationship between T-score and fracture risk?
- T-score -1: 12% bone loss, 2x fracture risk
- T-score -2: 24% bone loss, 4x fracture risk
- T-score -3: 36% bone loss, 8x fracture risk
- T-score -4: 48% bone loss, 16x fracture risk
What does the FRAX tool estimate?
10-year fracture risk (hip or major osteoporotic fractures) using clinical risk factors ± femoral neck BMD.
What does the Trabecular Bone Score (TBS) evaluate?
Bone quality using DXA lumbar spine images.
What are nonmodifiable risk factors for osteoporosis?
- Age
- Race (Caucasian, Asian)
- Female gender
- Early menopause
- Slender build
- Family history
What are modifiable risk factors for osteoporosis?
- Low calcium/vitamin D intake
- Estrogen deficiency
- Sedentary lifestyle
- Smoking
- Alcohol
- Caffeine
What are some secondary causes of low BMD?
- Osteomalacia
- Osteogenesis imperfecta
- Hyperparathyroidism
- Hyperthyroidism
- Alcoholism
- Celiac disease
What laboratory tests are used to evaluate secondary causes of osteoporosis?
- Calcium
- Albumin
- Phosphorus
- Creatinine
- 25-OH vitamin D
- Testosterone (men)
What are risk factors for frequent falls?
- Frailty
- Sedative use
- Visual/cognitive impairment
- Lower extremity disability
- Home obstacles
