Abstract
Objective: To determine the bone mineral content in cancellous lumbar vertebral bone as a function of age and gender using Quantitative Computed Tomography (QCT) technique.
Methods: This non-interventional descriptive study was carried out at Radiology department of Military Hospital (MH) Rawalpindi from January 2002 to January 2003. The bone mineral densities of cancellous part of first three lumbar vertebrae were calculated by QCT using
the bone mineral density phantom provided by the manufacturer. Data was collected from a total of 145 cases, 130 males and 15 females. Patients presenting for CT scan examination having no chronic illness or any disease condition which may affect the bone mineral density (BMD) were selected.
Results: The mean BMD for the males was 166.4±35.8 mg HOA/cm3 (range 207.4). The mean BMD for the females was 154.6±47.1 mg HOA/cm3 (range 144.1).The highest mean value in males was seen in 20-29 year age group. For females the highest mean value was seen in 30-39 year age group.
Conclusion: The BMD of lumbar vertebrae was found to gradually increase in the initial years of life reaching a peak in second or third decade. A gradual decline in the values was noted in cases of males. In females there was a sharp decline around the age of menopause.
(Rawal Med J 2009;34:4-6).

Key words: Bone mineral density, age, gender, Quantitative computed tomography, lumbar vertebrae.