Three-dimensional spinal morphology can differentiate between progressive and nonprogressive patients with adolescent idiopathic scoliosis at the initial presentation: a prospective study.
METHODS
This is a prospective case-control study.


OBJECTIVE
The objective of this study was to compare 3-dimensional (3D) morphological parameters of the spine at the first visit between a nonprogressive (NP) and a progressive (P) group of immature adolescent idiopathic scoliosis (AIS).


BACKGROUND
Prediction of curve progression remains challenging in AIS at the first visit. Prediction of progression is based on curve type, curve magnitude, and skeletal or chronological age.


METHODS
A prospective cohort of 133 AIS was followed from skeletal immaturity to maturity (mean, 37 mo). The first group was made up of patients with AIS with a minimum 6-degree progression of the major curve between the first and last follow-up (P) (n = 53) and the second group was composed of patients with NP who reached maturity with less than 6-degree progression (n = 81). Computerized measurements were taken on reconstructed 3-dimensional (3D) spine radiographs of the first visit. There were 6 categories of measurements: angle of plane of maximum curvature, Cobb angles (kyphosis, lordosis), 3D wedging (apical vertebra, apical disks), rotation (upper and lower junctional vertebra, apical vertebra, and thoracolumbar junction), torsion, and slenderness (height/width ratio). t tests were also conducted.


RESULTS
There was no statistical difference between the 2 groups for age and initial Cobb angle. P presented significant hypokyphosis, and parameters related to rotation presented significant statistical differences between NP and P (plane of maximal curvature, torsion, and apical axial rotation). Depth slenderness also presented statistical differences.


CONCLUSIONS
This study confirms that even at the initial visit, 3D morphological differences exist between P and NP AIS. It supports the use of 3D reconstructions of the spine in the initial evaluation of AIS to help predict outcome.
*Research Center, Sainte-Justine University Hospital Center, Montreal, Quebec, Canada †Department of Surgery, Faculty of Medicine, University of Montreal, Montreal, Quebec, Canada; and ‡Departement de genie de la production automatisee, Ecole de technologie superieure, Montreal, Quebec, Canada.
Marie-Lyne
ML
Nault
Jean-Marc
JM
Mac-Thiong
Marjolaine
M
Roy-Beaudry
Isabelle
I
Turgeon
Jacques
J
Deguise
Hubert
H
Labelle
Stefan
S
Parent
D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D011859:Radiography; D012600:Scoliosis / Q000000981:diagnostic imaging* / Q000601:surgery; D013123:Spinal Fusion; D013131:Spine / Q000000981:diagnostic imaging* / Q000601:surgery