Talk:Subjective Assessment of the Lumbar Spine

This rule attempts to diagnose vertebral fractures in patients without the use of expensive and overly sensitive imaging devices. This rule may be employed in two different settings: low risk and high risk settings.

The only difference in the use of the rule is the setting in which it is employed. The setting determines the pre-test probability, or prevalence.

Prevalence of the Pathology: The base rate of vertebral fractures in a population of 1,172 patients accessing primary care for treatment of lower back pain in Sydney, Australia was 0.5%. Primary care in Australia is defined as offices of physicians, physical therapists and chiropractors.

Prevalence of the Pathology: The base rate of vertebral fractures in a population of 1,172 patients accessing the emergency room and specialty physicians’ offices for treatment of lower back pain in Sydney, Australia was 3.0%.

The predictive power of the decision rule varies with the setting the clinician sees the patient – high risk patients seen in specialty clinics are more likely to have a fracture.

Clinicians may have difficulty deciding if patients evaluated with the low risk rule in primary care settings with three or more variables present constitute a high risk for vertebral fracture since the post test probability is barely better than chance (~52%). In these situations, the use of clinical intuition and experience supplements the algorithmic decision rule.