Diagnostic value of musculoskeletal ultrasound in patients with low back pain - a review of the literature.

Patients with low back pain (LBP) frequently undergo various imaging studies in the pursuit of a more precise diagnosis. Ultrasound (US) has the advantage of being a widely available, multiplanar, fast and radiation-free diagnostic tool. Moreover, compared to most of the other imaging modalities, it is particularly efficient in the visualization and assessment of soft tissues. Consequently, the question about the possible diagnostic application of US in such a common pathology as LBP is very relevant to the clinical practice. For this reason, we performed a review of the literature on the diagnostic value of US in differentconditions that could cause LBP. We hereby discuss available studies on the diagnostic application of US in spinal canal stenosis and disc herniation (probably of historical significance only), as well as in the pathology of soft tissue structures like the lumbar and pelvic ligaments, muscles and entheses, the thoracolumbar fascia and the sacroiliac joints (maybe of greater importance nowadays). The evidence for the diagnostic value of US is not equivocal, though promising for some of the causative conditions, and clearly this area remains open to further research.