Vertebral fracture rare cause of low back pain
MedWire News: Vertebral fracture is the most common serious undiagnosed condition among patients with acute low back pain, Australian study findings show.
However, the researchers found that serious pathology was rare in patients attending their primary care physician with acute low back pain, making up less than 1% of cases.
Christopher Maher (University of Sydney, New South Wales) and co-workers examined the prevalence of serious pathology among 1172 patients receiving primary care for low back pain and looked for “red flags” that can help identify these cases.
Just 11 (0.9%) patients were diagnosed with serious pathology, with vertebral fractures detected in eight patients. Two patients were diagnosed with inflammatory arthritis and one with cauda equine syndrome.
However, 80.4% of patients presenting with acute low back pain had at least one of 25 possible red flags for serious disease, prompting the researchers to suggest that “some red flags have very high false-positive rates, indicating that, when used in isolation, they have little diagnostic value in the primary care setting.”
Indeed, just three of the four red flags for fracture had significant likelihood ratios (LRs) for vertebral fracture, namely prolonged use of corticosteroids, significant trauma, and age over 70 years, with LRs of 48.5, 10.0, and 11.0, respectively.
When combined, female gender, age over 70 years, significant trauma, and prolonged use of corticosteroids was modestly associated with vertebral fracture. When three of the four factors were present the LR for vertebral fracture was 218.3.
However, due to the small number of affected patients, the researchers note that the LRs had wide confidence intervals. “A more precise diagnostic rule may be developed in a larger cohort with more cases of vertebral fracture,” the team suggests.
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By Lynda Williams