Diagnosis of lumbar spinal stenosis: an updated systematic review of the accuracy of diagnostic tests.

STUDY DESIGN: Systematic review of diagnostic studies.

OBJECTIVE: To update our previous systematic review on the diagnostic accuracy of tests used to diagnose lumbar spinal stenosis.

SUMMARY OF BACKGROUND DATA: A wide range of clinical, radiological, and electrodiagnostic tests are used to diagnose lumbar spinal stenosis. An accurate diagnosis is vital, because lumbar spinal stenosis may require specific medical advice and treatment. Therefore, it is important to know the accuracy of these diagnostic tests currently available.

METHODS: A comprehensive literature search was conducted for original diagnostic studies on lumbar spinal stenosis, in which one or more diagnostic tests were evaluated with a reference standard, and diagnostic accuracy was reported or could be calculated. Our previous systematic review included studies up to March 2004; this review is current up to March 2011. Included studies were assessed for their methodological quality using the QUADAS tool. Study characteristics and reported diagnostic accuracy were extracted.

RESULTS: Twenty-two additional articles in addition to the 24 included in the previous review met the inclusion criteria. Combined, this resulted in 20 articles concerning imaging tests, 11 articles evaluating electrodiagnostic tests, and 15 articles evaluating clinical tests. Estimates of the diagnostic accuracy of the tests differed considerably.

CONCLUSION: There is a need for a consensus on criteria to define and classify lumbar spinal stenosis. At present, the most promising imaging test for lumbar spinal stenosis is magnetic resonance imaging, avoiding myelography because of its invasiveness and lack of superior accuracy. Electrodiagnostic studies showed no superior accuracy for conventional electrodiagnostic testing compared with magnetic resonance imaging. These tests should be considered in the context of those presenting symptoms with the highest diagnostic value, including radiating leg pain that is exacerbated while standing up, the absence of pain when seated, the improvement of symptoms when bending forward, and a wide-based gait.