Question: What is a T-score?

Answer: A T-score compares an adult’s results with the mean peak bone mass (thickness of bones) of a large number of normal females and males between the ages of 20-40.

Question: What is a Z score result?

Answer: A Z score compares the patient’s score with their own age group: this is usually used in the diagnosis of the spine in children and adolescents. Their bone age should also be compared to their chronological age by taking an x-ray of the bones of their non-dominant hand.

Question: Can you explain the T-score reading?

Answer: The IOS has broken up the scores in the osteopenia range to make it easier for people to know exactly where they are on the scale.

  • Mild Osteopenia T-score = -1 to -1.49
  • Moderate Osteopenia T-score = -1.5 to -1.9
  • Marked Osteopenia T-score = -2 to -2.49
  • Osteoporosis T-score = Greater than -2.5
  • Severe Osteoporosis T- score = -3 and higher. (-4.5, -5.3)

A fragility fracture (broken bone from a trip and fall from a standing position or less) is also considered to be Osteoporosis unless proven otherwise.

Research shows that most fractures (broken bones) occur within a T score of -1.5 to -2.49 which is the moderate to marked Osteopenia range.

If a person has developed a hump on the back, an LVA (Lateral Vertebral Assessment) of the thoracic spine (the area where the hump is located) is usually recommended if available. If not available, a lateral x-ray of the spine is advised. This will show if the shape of the bones in this area are compressed due to an Osteoporosis fracture.

NOTE: Many people have arthritis and Osteophytes (extra bony spurs) which may have developed on the lumbar spine, which can give a false higher bone density reading. This would make your bones appear healthier than they are.

A DXA scan usually only measures your lumbar spine (lower back = L1, L2, L3 and L4) and your hips, neck of femur and greater trochanter. The upper back (LVA) is usually not done unless specifically requested on the referral form.

Would you like to discuss your bone health?

The Irish Osteoporosis Society is offering a new service.

You can contact us to book a 30-minute appointment on (01) 637 5050.

The cost of the service is free for Irish Osteoporosis Society members and €80 for a non-member.

All funds will go towards the Charities’ day to day services.