Opportunistic Computed Tomography: A Novel Opportunity for Osteoporosis Screening

Clin Spine Surg. 2024 Oct 29. doi: 10.1097/BSD.0000000000001710. Online ahead of print.

Abstract

Study design: Retrospective review.

Objective: To use opportunistic computed tomography (CT) screening to determine the prevalence of osteoporosis (OP) in patients presenting with spinal fractures and the rate of identification and treatment at our institution.

Background: OP remains a highly underdiagnosed and undertreated disease. Opportunistic abdominopelvic CT scans offer a feasible, accessible, and cost-effective screening tool for OP.

Methods: Retrospective review of 519 patients presenting as trauma activation to the emergency department of a Level 1 Trauma Center after a spinal fracture. Patients were excluded if under the age of 18 or lacking a CT scan upon arrival in the emergency department. Hounsfield Units (HU) were measured at the L1 vertebral level on CT scans to determine bone density levels. Values of ≤100 HU were considered osteoporotic, whereas 101-150 HU were osteopenic.

Results: A total of 424 patients were included. The average HU was 204.8 ± 74.3 HU. Of the patients, 16.7% were diagnosed as osteopenic and 9.9% as osteoporotic. The mean age was 65 ± 14 years for osteopenic patients and 77 ± 11 years for osteoporotic. A statistically significant inverse relationship was found between age and bone density. Of the patients, 42.5% with low bone density HU measurements had a previously documented history of OP/osteopenia. There was a statistically significant association between females and low bone density. Patients injured in a fall were statistically significantly more likely to have lower bone densities than those in motor vehicle accidents. Of the osteoporotic patients, 9.5% were treated by our institution's fragility fracture team.

Conclusions: Our study shows that among a cohort of patients with spinal fractures, 58% of patients with radiographic signs of OP are currently undiagnosed, resulting in a low treatment rate of OP. Increasing and standardizing the use of opportunistic CT scans would allow an increase in the diagnosis and treatment of OP in patients with spinal fractures. Further, opportunistic CT scans could also be useful for a broader orthopedic population at high risk of fragility fractures.

Level of evidence: Level II-therapeutic.