Shear Wave Elastography can evaluate Annulus Fibrosus Alteration in Adolescent Scoliosis

Abstract

Objectives In vitro studies showed that annulus fibrosus lose its integrity in idiopathic scoliosis. Shear wave ultrasound elastography can be used for noninvasive measurement of shear wave speed (SWS) in vivo in the annulus fibrosus, a parameter related to its mechanical properties. The main aim was to assess SWS in lumbar annulus fibrosus of scoliotic adolescents and compare it to healthy subjects. Methods SWS was measured in 180 lumbar IVDs (L3L4, L4L5, L5S1) of thirty healthy adolescents (13 yo ± 1.9) and thirty adolescent idiopathic scoliosis patients (13 yo ± 2, Cobb angle: 28.8° ± 10.4°). SWS was compared between scoliosis and healthy control group. Results In healthy subjects, average SWS (all disc levels pooled) was 3.0 ± 0.3 m/s whereas, in scoliotic patients it was significantly higher at 3.5 ± 0.3 m/s (p = 0.0004; Mann-Whitney test). Differences were also significant at all disc levels. No difference was observed between males and females. No correlation was found with age, weight and height. Conclusion Non-invasive shear wave ultrasound is a novel method of assessment to quantitative alteration of annulus fibrosus. These preliminary results are promising to consider shear wave elastography as a biomechanical marker for assessment of idiopathic scoliotic.