Nerve stiffness - a challenge for ultrasound elastography

Nerve stiffness associated with limb movements was a challenge for sonoelastography in the diagnosis of sciatic nerve entrapment in deep gluteal syndrome. The sciatic nerve was scanned by ultrasound strain elastography, during limb movements, in healthy persons (62) and in patients with deep gluteal syndrome (108). The results were presented by “B” mod, color maps and strain ratio. In flexion movements sciatic nerve diameters were statistically significantly lower, than in extension movement in both groups (p<0.001). Patients with deep gluteal syndrome, had significantly lower diameters of sciatic nerves (p<0.001), than the healthy group of persons. The group of healthy persons had significant increase of strain value (p<0.001) from extension to flexion movement of leg. The group of patients with deep gluteal syndrome had significant increase of strain value (p<0.001) in extension and in flexion movement of leg, than the healthy persons. In deep gluteal syndrome the specificity of method was 93.5%. sensitivity was 88.9%, with accuracy of 90.6%. Strain elastography imaging is currently the only diagnostic procedure based on the assessment of nerve stiffness with crucial information about the degree of nerve entrapment.