Investigations

Question 1

How is osteoporosis diagnosed?

Answer 1

DEXA Scan to measure Bone Mineral Density (BMD)

Question 2

What is the difference between a T-score and a Z-score in BMD?

Answer 2

T-Score: the number of standard deviations by which a patient’s BMD varies from the young adult mean for their sex

Z-Score: number of standard deviations a person’s BMD varies from the age- and sex-matched mean BMD

Question 3

What T-score is diagnostic of osteoporosis?

Answer 3

-2.5 or lower

Question 4

What is the appropriate interpretation of a T-score of -1 or higher?

A: Normal
B: Osteopenia / low bone density
C: Osteoporosis

Answer 4

A: Normal

Question 5

What T-score indicates osteopenia (low bone density)?

Answer 5

Between - 1 and -2.5

Question 6

The World Health Organization classifies low BMD according to T-score as either osteoporosis or osteopenia.

These definitions only apply to BMD measurements taken at which 3 locations?

Answer 6

• Femoral neck
• Total hip
• Lumbar spine

Question 7

List 3 red flags for back pain which are indications for imaging

Answer 7

• Neurological deficits (e.g. cauda equina)
• Cancer (systemic symptoms)
• Vertebral compression fracture