II. Indications: Osteoporosis Evaluation
- Patient is indecisive on starting Estrogen Replacement
- Direct management of asymptomatic Hyperparathyroidism
- Incidental radiographic evidence of bone loss
- Signs of Osteoporosis in female patients
- Height loss
- Osteoporotic Fracture
- Patients at high risk for Osteoporosis
- See Osteoporosis Evaluation for risk factors
- Longterm Corticosteroids (Prednisone 7.5 mg/day)
- AACE: Corticosteroid use for over 1 month
- Medicare: Corticosteroid use for over 3 months
- Monitor benefits of current Osteoporosis Management
III. Imaging Modalities
IV. Score Types
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General
- Scores are not interchangeable across imaging types
- Scores are based on standard deviations below mean
- Example: T-Score of -2 is two S.D. below the mean
- T-Score (WHO standard BMD measure)
- Z-Score
- Mean based on women of similar Osteoporosis risk
- Accounts for age, weight, and ethnicity
- Fracture risk increases 2x per Z unit
V. Interpretation: T-Score or Z-Score
- Normal: <1 Standard Deviation (SD) below the mean (T Score >=-1.0)
- Osteopenia: 1.0 to 2.5 SD below the mean (T Score -1.0 to -2.5)
- Osteoporosis: >2.5 SD below the mean (T Score <-2.5)
VI. Prognosis
- Risk of Fracture also related to scoring above
- Bone Mineral Density more than 2 SD below mean
- Risk of Fracture increases exponentially
- Each 10% decrease in spinal Bone Mineral Density
- Each 15% decrease in hip Bone Mineral Density
- Associated with 2.5 times risk of Hip Fracture
- References