ULTRASOUND
Shear-wave elastography can evaluate annulus fibrosus alteration
in adolescent scoliosis
Tristan Langlais
1,2
&
Claudio Vergari
2
&
Raphael Pietton
1,2
&
Jean Dubousset
2
&
Wafa Skalli
2
&
Raphael Vialle
1
Received: 3 November 2017 /Revised: 6 December 2017 /Accepted: 3 January 2018 /Published online: 5 February 2018
#
European Society of Radiology 2018
Abstract
Objectives In vitro studies showed that annulus fibrosus lose its integrity in idiopathic scoliosis. Shear-wave ultrasound
elastography can be used for non-invasive 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 30 healthy adolescents (13 ± 1.9 years old) and 30
adolescent idiopathic scoliosis patients (13 ± 2 years old, Cobb angle: 28.8° ± 10.4°). SWS was compared between the scoliosis
and healthy control groups.
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 for considering shear-wave elastography as a biomechanical marker for assessment of
idiopathic scoliosis.
Key Points
• Adolescent idiopathic scoliosis may have an altered lumbar annulus fibrosus.
• Shear-wave elastography can quantify lumbar annulus fibrosus mechanical properties.
• Shear-wave speed was higher in scoliotic annulus than in healthy subjects.
• Elastography showed potential as a biomechanical marker for characterizing disc alteration.
Keywords Scoliosis
.
Paediatrics
.
Spine
.
Elasticity imaging techniques
.
Annulus fibrosus
Abbreviations
AF Annulus Fibrosus
IVD Intervertebral Disc
MRI Magnetic Resonance Imaging
SWS Shear-Wave Speed
Introduction
Adolescent idiopathic scoliosis is a three-dimensional spinal de-
formity of unknown aetiology defined in the coronal plane by a
Cobb angle of at least 10° and an axial rotation of the vertebrae
[1] . Prevalence varies from 1 to 3%, pathogenesis and progres-
sion risk are not yet fully understood [2–4], although reasons and
risk factors for adolescent scoliosis have been proposed [5]. The
main challenge is to obtain a better understanding of these factors
to establish the appropriate treatment [6, 7].
Numerous studies have addressed changes of bone struc-
tures in scoliotic patients’ spines [8–11], but only a few have
focused on the intervertebral disc (IVD), although it probably
plays an important role in the vicious cycle leading to curve
progression [12]. Recent numerical simulation found a link
between progressive scoliosis and a change in IVD mechanical
* Tristan Langlais
tristanlanglais@yahoo.fr
1
Department for Innovative Therapies in Musculoskeletal Diseases,
DHU MAMUTH - Department of Pediatric Orthopaedic, Armand
Trousseau Hospital, Université Pierre et Marie Curie Paris 6 - 26
avenue du Dr Arnold Netter, 75571 Paris Cedex 12, France
2
Arts et Metiers ParisTech, LBM/Institut de Biomécanique Humaine
Georges Charpak, 151 boulevard de l’hôpital, 75013 Paris, France
European Radiology (2018) 28:2830–2837
https://doi.org/10.1007/s00330-018-5309-2
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