Application of Ultrasound Shear Wave Elastography as an Objective Outcome Measure in Nonspecific Low Back Pain Associated with Myofascial Trigger Points.

The sample size was calculated for reliability testing, so it may be too small to support the clinical associations or group comparisons. Only a small group with nonspecific low back pain and a small matched control group were studied, and most had moderate pain and minimal disability. Only a radiologist and a physiotherapist performed the measurements, so it does not show how the method performs across more raters or clinics. Measurements were taken at rest and not directly over individual trigger points, so the method may miss localized muscle changes or changes during contraction. The ultrasound method has limited depth, so it may not work well in people with thick adipose tissue. Responsiveness to treatment was not tested, so it is unknown whether stiffness values change after therapy. No self-reported stiffness measure was collected, so the relationship between patient-reported stiffness and ultrasound values is unknown.

The investigators reported no financial or nonfinancial disclosures.

Do not use these ultrasound stiffness values as a diagnostic test or as proof that a treatment works. This was a preliminary study with very few raters, and it did not test whether the measurements change care or respond to treatment.