title: A comparison of four techniques to measure anterior and posterior vertebral body heights and sagittal plane wedge angles in adolescent idiopathic scoliosis.
abstract: Adolescent idiopathic scoliosis (AIS) is a three-dimensional (3D) spinal deformity of unknown aetiology. Increased growth of the anterior part of the vertebrae known as anterior overgrowth has been proposed as a potential driver for AIS initiation and progression. To date, there has been no objective evaluation of the 3D measurement techniques used to identify this phenomenon and the majority of previous studies use 2D planar assessments which contain inherent projection errors due to the vertebral rotation which is part of the AIS deformity. In this study, vertebral body (VB) heights and wedge angles were measured in a test group of AIS patients and healthy controls using four different image analysis and measurement techniques. Significant differences were seen between the techniques in terms of VB heights and VB wedge angles. The low variability, and the fact that the rotation and tilt of the deformed VBs are taken into account, suggests that the proposed technique using the full 3D orientation of the vertebrae is the most reliable method to measure anterior and posterior VB heights and sagittal plane wedge angles in 3D image data sets. These results have relevance for future investigations that aim to quantify anterior overgrowth in AIS patients for comparison with healthy controls.
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia. n.newell09@imperial.ac.uk.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia. n.newell09@imperial.ac.uk.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Newell
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia.
authors.forename: Caroline A
authors.initials: CA
authors.lastname: Grant
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia.
authors.forename: Bethany E
authors.initials: BE
authors.lastname: Keenan
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia.
authors.forename: Maree T
authors.initials: MT
authors.lastname: Izatt
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Pearcy
authors.affiliation: Paediatric Spine Research Group, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.|Mater Health Services Brisbane Ltd, Brisbane, QLD, Australia.
authors.forename: Clayton J
authors.initials: CJ
authors.lastname: Adam
mesh_terms: D001827:Body Height; D016022:Case-Control Studies; D002648:Child; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D013131:Spine / Q000000981:diagnostic imaging / Q000254:growth & development / Q000503:physiopathology
keywords: Adolescent idiopathic scoliosis; Anterior overgrowth; MRI; Spinal deformity; Vertebral body