Screening for osteoporosis after trauma: a new approach using quantitative computed tomography of the skull.

Abstract

The diagnosis of osteoporosis is important in the care of elderly patients at risk of trauma. While pelvis computed tomography (CT) is accurate in the measurement of bone mineral density, axial skull CT has not previously been evaluated for this purpose. This study investigated whether data from axial skull CT scans can screen for osteoporosis. Bone density measurements were derived from digital analysis of routine scans of the head and pelvis using quantitative CT. The study took place from October 2010 to November 2011 at a medium-sized community hospital. The first study phase included patients older than 18 years who had both a head and a pelvis CT scan within 30 days. The known diagnostic value for osteoporosis on pelvis CT scans was used to derive a diagnostic value for head CT. The second study phase included adult trauma patients who underwent noncontrast head CT during an initial trauma evaluation. A subgroup analysis was performed during Phase II on patients older than 65 years to identify the incidence of fracture as it is affected by age and bone mineral density. Our data demonstrated that head CT was able to identify osteoporosis with a sensitivity of 0.70, a specificity of 0.81, and an accuracy of 0.76 compared with pelvic CT. Of 261 trauma patients, 54% had bone disease based on axial skull CT criteria. Patients older than 65 years with a positive screen result for osteoporosis on head CT were twice as likely to have a fracture. Analysis of data from head CT scans has the potential to provide a useful screen for osteoporosis. Adding this analysis to CT scans performed for elderly trauma patients could result in improved diagnosis and treatment of osteoporosis. Diagnostic study, level II.