Marjolaine Roy-Beaudry

Spinal Cord Injury in the Pediatric Population: A Systematic Review of the Literature

Spinal Cord Injury (SCI) in the pediatric population is relatively rare but carries significant psychological and physiological consequences. An interdisciplinary group of experts composed of medical and surgical specialists treating patients with SCI formulated the following questions: 1) What is the epidemiology of pediatric spinal cord injury and fractures?; 2) Are there unique features of pediatric SCI which distinguish the pediatric SCI population from adult SCI?; 3) Is there evidence to support the use of neuroprotective approaches, including hypothermia and steroids, in the treatment of pediatric SCI? A systematic review of the literature using multiple databases was undertaken to evaluate these three specific questions. A search strategy composed of specific search terms (Spinal Cord Injury, Paraplegia, Quadriplegia, tetraplegia, lapbelt injuries, seatbelt injuries, cervical spine injuries and Pediatrics) returned over 220 abstracts that were evaluated and by two observers. Relevant abstracts were then evaluated and papers were graded using the Downs and Black method. A table of evidence was then presented to a panel of experts using a modified Delphi approach and the following recommendation was then formulated using a consensus approach: Pediatric patients with traumatic SCI have different mechanisms of injury and have a better neurological recovery potential when compared to adults. Patients with SCI before their adolescent growth spurt have a high likelihood of developing scoliosis. Because of these differences, traumatic SCI should be highly suspected in the presence of abnormal neck or neurological exam, a high-risk mechanism of injury or a distracting injury even in the absence of radiological anomaly.

Reliability and validity of adapted French Canadian version of Scoliosis Research Society Outcomes Questionnaire (SRS-22) in Quebec.

Study Design. Prospective validation study of a cross-cultural adaptation of the Scoliosis Research Society (SRS) Outcomes Questionnaire. Objective. To provide a French Canadian version of the SRS Outcomes Questionnaire and to empirically test its response in healthy adolescents and adolescent idiopathic scoliosis (AIS) patients in Québec. Summary of Background Data. The SRS Outcomes Questionnaire is widely used for the assessment of health-related quality of life in AIS patients. Methods. French translation and back-translation of the SRS-22 (SRS-22-fv) were done by an expert committee. Its reliability was measured using the coefficient of internal consistency, construct validity with a factorial analysis, concurrent validity by using the short form-12 and discriminant validity using ANOVA and multivariate linear regression, on 145 AIS patients, 44 patients with non clinically significant scoliosis (NCSS), and 64 healthy patients. Results. The SRS-22-fv showed a good global internal consistency (AIS: Cronbach &agr; = 0.86, NCSS: 0.81, and controls: 0.79) and in all of its domains for AIS patients. The factorial structure was coherent with the original questionnaire (47.4% of explained variance). High correlation coefficients were obtained between SRS-22-fv and short form-12 corresponding domains. Boys had higher scores than girls, scores worsened with age, and with increasing body mass index. Mean Total, Pain, Self-image, and Satisfaction scores, were correlated with Cobb angle. Adjusted regression models showed statistically significant differences between the AIS, NCSS, and control groups in the Total, Pain, and Function scores. Conclusion. The SRS-22-fv showed satisfactory reliability, factorial, concurrent, and discriminant validity. This study provides scores in a significant group of healthy adolescents and demonstrates a clear gradient in response between subjects with AIS, NCSS, and controls.

Spinal appearance questionnaire: factor analysis, scoring, reliability, and validity testing.

Study Design. Cross sectional. Objective. This study presents the factor analysis of the Spinal Appearance Questionnaire (SAQ) and its psychometric properties. Summary of Background Data. Although the SAQ has been administered to a large sample of patients with adolescent idiopathic scoliosis (AIS) treated surgically, its psychometric properties have not been fully evaluated. This study presents the factor analysis and scoring of the SAQ and evaluates its psychometric properties. Methods. The SAQ and the Scoliosis Research Society-22 (SRS-22) were administered to AIS patients who were being observed, braced or scheduled for surgery. Standard demographic data and radiographic measures including Lenke type and curve magnitude were also collected. Results. Of the 1802 patients, 83% were female; with a mean age of 14.8 years and mean initial Cobb angle of 55.8° (range, 0°–123°). From the 32 items of the SAQ, 15 loaded on two factors with consistent and significant correlations across all Lenke types. There is an Appearance (items 1–10) and an Expectations factor (items 12–15). Responses are summed giving a range of 5 to 50 for the Appearance domain and 5 to 20 for the Expectations domain. The Cronbachs &agr; was 0.88 for both domains and Total score with a test–retest reliability of 0.81 for Appearance and 0.91 for Expectations. Correlations with major curve magnitude were higher for the SAQ Appearance and SAQ Total scores compared to correlations between the SRS Appearance and SRS Total scores. The SAQ and SRS-22 Scores were statistically significantly different in patients who were scheduled for surgery compared to those who were observed or braced. Conclusion. The SAQ is a valid measure of self-image in patients with AIS with greater correlation to curve magnitude than SRS Appearance and Total score. It also discriminates between patients who require surgery from those who do not.

Three-Dimensional Spinal Morphology Can Differentiate Between Progressive and Nonprogressive Patients With Adolescent Idiopathic Scoliosis at the Initial Presentation: A Prospective Study

Study Design. 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). Summary of Background Data. 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. Conclusion. 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. Level of Evidence: 3

Patient characteristics at the initial visit to a scoliosis clinic: a cross-sectional study in a community without school screening.

Study Design. A cross-sectional study was conducted of all patients referred for an initial visit to the orthopedic outpatient clinic of a metropolitan pediatric hospital in Canada for suspected adolescent idiopathic scoliosis (AIS). Objective. To document the appropriateness of current referral patterns for AIS in comparison to those that were prevailing before discontinuation of school screening in Canada. Summary of Background Data. The consequences of the discontinuation of school scoliosis screening programs on the referral patterns of AIS patients remain unknown. Methods. The clinical and radiologic charts of the 636 consecutive patients referred for scoliosis evaluation over a 1-year period were reviewed. Patients were classified according to defined criteria of appropriateness of referral based on skeletal maturity and curve magnitude. Results. Of the 489 suspected cases of AIS, 206 (42%) had no significant deformity (Cobb angle <10°) and could be considered as inappropriate referrals. In subjects with confirmed AIS, 91 patients (32%) were classified as late referrals with regards to brace treatment indications. Conclusions. These findings suggest that current referral mechanisms for AIS are leading to a suboptimal case-mix in orthopedics in terms of appropriateness of referral.

A Modified Risser Grading System Predicts the Curve Acceleration Phase of Female Adolescent Idiopathic Scoliosis

BACKGROUND The Risser sign can be assessed with the United States method or the European method. The Tanner-Whitehouse method estimates skeletal age on the basis of hand radiography and digital skeletal age. Digital skeletal age scores between 400 and 425 are associated with the beginning of the curve acceleration phase or peak growth velocity in adolescent idiopathic scoliosis. The first objective of the present study was to evaluate the agreement between the two Risser grading systems. The second objective was to identify which grading system best predicts a digital skeletal age of between 400 and 425. The third objective was to explore a new system that could be used to replace the Risser method. METHODS One hundred female patients with adolescent idiopathic scoliosis were recruited in this cross-sectional descriptive study. Each patient was evaluated with posteroanterior spine and hand radiographs. The Risser sign was measured according to both the United States and European grading systems. Digital skeletal age was calculated, and triradiate cartilage ossification was assessed. RESULTS With use of kappa statistics, moderate agreement between the United States and European grading systems was seen. Risser stages alone were not good predictors of the curve acceleration phase. A new system with three groups was tested, and the second group (Risser 0 with closed triradiate cartilage and Risser 1) was the best predictor of a digital skeletal age score of between 400 and 425. CONCLUSIONS Two Risser grading systems coexist, and the agreement between them is moderate. No Risser stage was found to be a good clinical landmark for the beginning of the curve acceleration phase of adolescent idiopathic scoliosis. A new group, Risser 0 with closed triradiate cartilage and Risser 1, was the best predictor of the beginning of the curve acceleration phase. This new system is easy to implement and is based on findings that are available on spine radiographs. It should be used at the first visit and for scoliosis follow-up to assess skeletal maturity and correlation with the curve acceleration phase.

Endothelin-1 in osteoarthritic chondrocytes triggers nitric oxide production and upregulates collagenase production

The mechanism of endothelin-1 (ET-1)-induced nitric oxide (NO) production, MMP-1 production and MMP-13 production was investigated in human osteoarthritis chondrocytes. The cells were isolated from human articular cartilage obtained at surgery and were cultured in the absence or presence of ET-1 with or without inhibitors of protein kinase or LY83583 (an inhibitor of soluble guanylate cyclase and of cGMP). MMP-1, MMP-13 and NO levels were then measured by ELISA and Griess reaction, respectively. Additionally, inducible nitric oxide synthase (iNOS) and phosphorylated forms of p38 mitogen-activated protein kinase, p44/42, stress-activated protein kinase/Jun-N-terminal kinase and serine-threonine Akt kinase were determined by western blot. Results show that ET-1 greatly increased MMP-1 and MMP-13 production, iNOS expression and NO release. LY83583 decreased the production of both metalloproteases below basal levels, whereas the inhibitor of p38 kinase, SB202190, suppressed ET-1-stimulated production only. Similarly, the ET-1-induced NO production was partially suppressed by the p38 kinase inhibitor and was completely suppressed by the protein kinase A kinase inhibitor KT5720 and by LY83583, suggesting the involvement of these enzymes in relevant ET-1 signalling pathways. In human osteoarthritis chondrocytes, ET-1 controls the production of MMP-1 and MMP-13. ET-1 also induces NO release via iNOS induction. ET-1 and NO should thus become important target molecules for future therapies aimed at stopping cartilage destruction.

Unique features of pediatric spinal cord injury.

Study Design. Systematic review. Objective. The objective of this systematic review was to identify the unique features associated with pediatric spinal cord injury (SCI) with the intention of determining the most effective spinal stabilization methods and identifying the optimum treatment for post-traumatic spinal deformity in pediatric patients with a SCI. Summary of Background Data. Spinal injuries occur in 1.99/100,000 children, 10% are under 15 years, 60% to 80% occur in the cervical spine, and 5.4% to 34% in the thoracolumbar spine. The most frequent incident of spinal injury (50%–56%) occurs during motor vehicle accidents. Methods. A systematic review of the English language literature explored articles published between 1950 and 2009. Electronic databases (Medline and Embase) and reference lists of key articles were searched to identify unique features of pediatric SCI based on 2 questions: (1) “What is the most effective means to achieve spinal stabilization in pediatric patients with a SCI?” and (2) “What is the most effective treatment of post-traumatic spinal deformities in pediatric patients with a SCI?” Three Spinal Trauma Study Group faculty members assessed the level of evidence using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) criteria and disagreements were resolved by a modified Delphi consensus. Results. No Level 1 or 2 evidence articles were discovered. Question 1 was addressed by 417 abstracts; from those 15 were selected for inclusion. This literature proved to be controversial, mostly focused on the adult population, pediatric series were retrospective, and most treatments were based on adult experience. The evidence supporting stabilization of the spine in the pediatric SCI population is very low for both the cervical and thoracic spinal regions. Question 2 was discussed in 517 abstracts; 8 relevant articles were selected. The principal key points, regarding the most effective treatment of post-traumatic spinal deformity in the pediatric SCI patients, suggest that the deformity should be prevented before the age of 10 to 12 years, younger SCI patients are unfavorable, nearly 100% of patients with SCI will develop a deformity, and brace treatment is generally recommended. Current evidence in support of brace use is very low. Conclusion. Despite the lack of well-designed prospective studies to establish the efficacy of instrumentation in these cases, there remains very low evidence that supports the use of instrumentation in unstable pediatric spines to prevent neurologic injury and maintain spinal alignment. The very low evidence of benefits from early bracing clearly outweighs the risks and complications associated with its use. Close monitoring should be initiated early so as to delay surgical correction as late as possible. There is very low evidence to support the use of surgery for the treatment of deformity triggered by a SCI. There may be evidence suggesting that the correction techniques used for neuromuscular deformities are useful for SCI patients. In conclusion, there is a strong recommendation for the use of instrumentation in the unstable pediatric spinal injured population, and there is a strong recommendation for traditional neuromuscular spinal deformity treatment techniques to be adopted as a treatment of progressive spinal deformities after a neurologic injury.

Three-dimensional spine parameters can differentiate between progressive and nonprogressive patients with AIS at the initial visit: a retrospective analysis.

Background: Knowledge concerning morphology of the spine is reported in 2-dimensional (2D) or focuses on modification of parameters with progression of spinal deformation. The objective of this study was to compare 3-dimensional (3D) morphologic parameters of the spine at the first visit between progressive and a nonprogressive group of immature adolescent idiopathic scoliosis (AIS). Methods: The first group was made up of surgically corrected AIS patients (E) (n=19), whereas the second group was composed of nonprogressive AIS that had reached skeletal maturity (n=18). Computerized measurements were undertaken on reconstructed 3D spines. There were 5 categories of measurement: Cobb angles (scoliosis, kyphosis, lordosis), 3D wedging (apical vertebra, mean 2 apical disks), rotation (upper and lower junctional vertebra, apical vertebra, and disk), torsion, and slenderness (height/width ratio of T6, L4, and T1-L5). Nonparametric Mann-Whitney tests were also undertaken. Results: There was no statistical difference between the 2 groups for age, 3D Cobb angle, lordosis, and kyphosis. Mean 3D wedging of the apical disks, lower junctional vertebral axial rotation, torsion and T6, and whole spine height/width ratio were all significantly affected. Conclusions: This study supports the theory that wedging begins in the disks and then in the vertebral body and identifies 3D morphologic parameters that could be used in the prediction of AIS evolution. The findings in the junctional area illustrate that a torsional deformity seems to occur distally from the apex and creates a progressive scoliosis. Curve progression could be predicted based on 3D morphometric parameters, as early as the initial visit. Level of Evidence: Level III—this is a case-control retrospective study.

3-D Morphology Prediction of Progressive Spinal Deformities From Probabilistic Modeling of Discriminant Manifolds

We introduce a novel approach for predicting the progression of adolescent idiopathic scoliosis from 3-D spine models reconstructed from biplanar X-ray images. Recent progress in machine learning has allowed to improve classification and prognosis rates, but lack a probabilistic framework to measure uncertainty in the data. We propose a discriminative probabilistic manifold embedding where locally linear mappings transform data points from high-dimensional space to corresponding low-dimensional coordinates. A discriminant adjacency matrix is constructed to maximize the separation between progressive (P) and nonprogressive (NP) groups of patients diagnosed with scoliosis, while minimizing the distance in latent variables belonging to the same class. To predict the evolution of deformation, a baseline reconstruction is projected onto the manifold, from which a spatiotemporal regression model is built from parallel transport curves inferred from neighboring exemplars. Rate of progression is modulated from the spine flexibility and curve magnitude of the 3-D spine deformation. The method was tested on 745 reconstructions from 133 subjects using longitudinal 3-D reconstructions of the spine, with results demonstrating the discriminatory framework can identify between P and NP of scoliotic patients with a classification rate of 81% and the prediction differences of 2.1° in main curve angulation, outperforming other manifold learning methods. Our method achieved a higher prediction accuracy and improved the modeling of spatiotemporal morphological changes in highly deformed spines compared with other learning methods.