title: Bone structural and mechanical indices in Adolescent Idiopathic Scoliosis evaluated by high-resolution peripheral quantitative computed tomography (HR-pQCT).
abstract: Adolescent Idiopathic Scoliosis (AIS) is associated with systemic low bone mass. It could persist into adulthood and was shown to be an important prognostic factor for curve progression in AIS. Previous studies were confined to areal bone mineral density (aBMD) measured by Dual-energy X-ray Absorptiometry (DXA) which was a two-dimensional measurement for a three-dimensional structure. This conventional measurement was inadequate to evaluate volumetric bone density and bone quality which are important determinants for bone strength and bone health status as defined in the 2000 NIH consensus statement. High-resolution peripheral quantitative computed tomography (HR-pQCT) was therefore used in this study for three-dimensional evaluation of volumetric bone mineral density and bone micro-architecture as well as estimation of bone strength. In this study, 214 newly diagnosed AIS girls and 187 age and gender-matched normal control aged between 11 and 13years old were recruited for HR-pQCT evaluations on bone geometry, trabecular bone micro-architecture and volumetric BMD (vBMD) at the non-dominant distal radius. We demonstrated that AIS was associated with lower Cortical Bone Area, Cortical Bone vBMD, Trabecular Number and greater Trabecular Separation. With multivariate linear regression analysis and after adjustment for age, dietary calcium intake and physical activity level, the association of AIS with lower Cortical Bone vBMD, lower Trabecular Number and greater Trabecular Separation remained statistically significant. The findings of this study indicated that AIS was associated with an abnormal bone quality profile suggestive of alteration in endocortical modeling, derangement in trabecular bone structure and disturbance in bone mineralization. The cause for these changes and how they are related to the etiopathogenesis of AIS warrant further studies.
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Wing Sze
authors.initials: WS
authors.lastname: Yu
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Ka Yan
authors.initials: KY
authors.lastname: Chan
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Fiona Wai Ping
authors.initials: FW
authors.lastname: Yu
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Bobby Kin Wah
authors.initials: BK
authors.lastname: Ng
authors.affiliation: Lee Hysan Clinical Research Laboratories, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Kwong Man
authors.initials: KM
authors.lastname: Lee
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Bone Quality and Health Assessment Centre, Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China.
authors.forename: Ling
authors.initials: L
authors.lastname: Qin
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China.
authors.forename: Tsz Ping
authors.initials: TP
authors.lastname: Lam
authors.affiliation: Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong, Shatin, Hong Kong, China; Joint Scoliosis Research Center of the Chinese University of Hong Kong and Nanjing University, Hong Kong and Nanjing, China. Electronic address: jackcheng@cuhk.edu.hk.
authors.forename: Jack Chun Yiu
authors.initials: JC
authors.lastname: Cheng
mesh_terms: D000293:Adolescent; D015519:Bone Density; D001842:Bone and Bones / Q000528:radiation effects*; D002648:Child; D005260:Female; D006801:Humans; D012600:Scoliosis / Q000000981:diagnostic imaging*; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Adolescent Idiopathic Scoliosis; Bone quality; Cortical bone; HR-pQCT; Low bone mass; Trabecular bone