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1.
Sci Rep ; 9(1): 10074, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296888

RESUMO

Adolescent idiopathic scoliosis is the most prevalent spine deformity and the molecular mechanisms underlying its pathophysiology remain poorly understood. We have previously found a differential impairment of melatonin receptor signaling in AIS osteoblasts allowing the classification of patients into three biological endophenotypes or functional groups (FG1, FG2 and FG3). Here, we provide evidence that the defect characterizing each endophenotype lies at the level of Gαi proteins leading to a systemic and generalized differential impairment of Gi-coupled receptor signaling. The three Gαi isoforms exhibited a selective serine phosphorylation patterns for each AIS endophenotype resulting in a differential reduction in Gαi protein activity as determined by cellular dielectric spectroscopy and small interfering RNA methods. We found that one endophenotype (FG2) with phosphorylated Gαi1 and Gαi2 was consistently associated with a significantly high risk of spinal deformity progression when compared to the other two endophenotypes (FG1 and FG3). We further demonstrated that each endophenotype is conserved among affected family members. This study expands our understanding of the mechanism underlying the Gi-coupled receptor signaling dysfunction occurring in AIS and provides the first evidence for its hereditary nature. Collectively, our findings offers a new perspective on Gαi hypofunctionality in a human disease by revealing specific serine phosphorylation signatures of Gαi isoforms that may facilitate the identification of AIS patients at risk of spinal deformity progression.


Assuntos
Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/metabolismo , Osteoblastos/metabolismo , Receptores de Melatonina/metabolismo , Escoliose/metabolismo , Adolescente , Células Cultivadas , Criança , Estudos de Coortes , Progressão da Doença , Feminino , Subunidades alfa Gi-Go de Proteínas de Ligação ao GTP/genética , Humanos , Masculino , Fenótipo , Prognóstico , Isoformas de Proteínas/genética , RNA Interferente Pequeno/genética , Risco , Escoliose/genética , Transdução de Sinais
2.
Clin Biomech (Bristol, Avon) ; 49: 107-112, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28918002

RESUMO

BACKGROUND: Generally, scoliotic girls have a tendency to lean further back than a comparable group of non-scoliotic girls. To date, no study has addressed how standing balance in untreated scoliotic girls is affected by a natural backwardly or forwardly inclined trunk. METHODS: 27 able-bodied young girls and 27 young girls with a right thoracic curve were classified as leaning forward or backward according to the median of their trunk sagittal inclination. Participants stood upright barefoot. Trunk and pelvis orientations were calculated from 8 bony landmarks. Upright standing balance was assessed by 9 parameters calculated from the excursion of the center of pressure and the free moment. FINDINGS: In the anterior-posterior direction, backward scoliotic girls had a greater center of pressure range (P=0.036) and speed (P=0.015) by 10.4mm and 2.8mm/s respectively than the forward scoliotic group. Compared to their matching non-scoliotic group, the backward scoliotic girls stood more on their heels by 14.6mm (P=0.017) and display greater center of pressure speed by 2.5mm/s (P=0.028). Medio-lateral center of pressure range (P=0.018) and speed (P=0.008) were statistically higher by 8.7mm and 3.6mm/s for the backward group. Only the free moment RMS was significantly larger (P=0.045) for the backward scoliotic group when compared to the forwardly inclined scoliotic group. INTERPRETATION: Only those with a backward lean displayed statistically significant differences from both forward scoliotic girls and non-scoliotic girls. Untreated scoliotic girls with an exaggerated back extension could profit more from postural rehabilitation to improve their standing balance.


Assuntos
Equilíbrio Postural/fisiologia , Escoliose/fisiopatologia , Tronco/fisiopatologia , Adolescente , Criança , Feminino , Humanos , Pelve , Pressão , Rotação
4.
Hum Factors ; 57(4): 557-66, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25977318

RESUMO

OBJECTIVE: The purposes of this study were to estimate head and trunk's (HT) radii of gyration (K) and moments of inertia (I) in able-bodied and unbraced scoliotic girls using an angular momentum method, to test if the use of mean ratios calculated in this study and given by de Leva present similar values compared to the experimental data, and to determine how these methods behave in estimation of scoliotic HT's K and I with variable Cobb angles. BACKGROUND: Scoliotic HT's I estimated from anthropometric tables can lead to error in joint muscle moment calculations. METHOD: Twenty-one unbraced scoliotic and 20 able-bodied girls participated. HT's I values were calculated using an angular momentum method. RESULTS: Angular momentum method provided greater HT's I for the scoliotic group compared with the able-bodied girls. HT's I obtained by the mean ratios calculated from this study were close to the measured values. Compared with the experimental I, de Leva method provided significantly lower I in the scoliotic group. Scoliotic HT's K and I obtained from angular momentum method showed greater correlations with the Cobb angles. CONCLUSION: The use of mean ratios obtained in this study to estimate HT's K values in unbraced scoliotic girls could overcome the drawbacks of current anthropometric methods. APPLICATION: These results can be used to calculate more precise moments of force during daily activities in scoliotic girls with mild scoliosis and to improve the design of corrective flexible body braces prescribed in cases of rapid interventions in young patients of moderate spinal deformities.


Assuntos
Fenômenos Biomecânicos/fisiologia , Cabeça/fisiologia , Movimento/fisiologia , Escoliose/fisiopatologia , Tronco/fisiologia , Adolescente , Estudos de Casos e Controles , Criança , Feminino , Humanos , Amplitude de Movimento Articular
5.
Spine J ; 15(3): 477-86, 2015 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-25463399

RESUMO

BACKGROUND CONTEXT: Scoliosis is a three-dimensional (3D) deformation of the spine and the pelvis. Although the relation between the pelvic asymmetries and scoliosis progression was proposed by several authors, it has not been documented over time in adolescent idiopathic scoliosis (AIS). PURPOSE: The objective was to determine whether vertebral wedging and pelvic asymmetries progress in the early stages of AIS before any orthopedic treatment. STUDY DESIGN: The study design included an observational cohort study. PATIENT SAMPLE: Nineteen AIS girls participated in this study. OUTCOME MEASURES: The outcome measures were pelvic and spine geometries from simultaneous biplanar radiographs. METHODS: At the diagnosis, the girls (12.6±1.3 years) had a Cobb angle of 13.9°±6.0°. At the end of their observation period (11 months on average), the scoliosis progressed to 20.5°±5.5°. Bone 3D geometry was reconstructed from biplanar radiographs. Sagittal and frontal wedgings were calculated for five vertebral levels, namely, at the apex and at the two vertebral bodies above and below it. The pelvic geometry was described using five 3D homologous right-left lengths to estimate pelvic asymmetries. Paired t tests were performed on vertebral wedging and pelvic asymmetries to assess their progression between the two evaluations. Principal component (PC) analyses were applied to determine whether vertebral wedging or pelvic asymmetries were predominant at each evaluation. RESULTS: Vertebral wedging was present at the diagnosis (1.76°-5.92°) and generally did not progress until brace prescription. The mean difference between the right and left pelvic normalized lengths was 1.4% and 2.4% for the initial and final evaluations, respectively. Results revealed the width of the right pelvis to be superior by 3%, and this asymmetry progressed to 4.0%. Principal component analysis revealed that initial vertebral wedging was present in seven out of eight parameters of the first three PCs, whereas at the final examination, vertebral wedging and pelvic asymmetries were evenly present. CONCLUSIONS: Our study confirms the presence of vertebral wedging at the early stages of scoliosis. This is the first to document the association between spinal and pelvic deformities over time. Pelvic asymmetries could be responsible for trunk muscle imbalances and lead to reduced neuromuscular control reported in AIS patients. These results could influence body brace fitting.


Assuntos
Ossos Pélvicos/diagnóstico por imagem , Escoliose/diagnóstico por imagem , Adolescente , Pontos de Referência Anatômicos , Fenômenos Biomecânicos , Mau Alinhamento Ósseo/diagnóstico por imagem , Mau Alinhamento Ósseo/fisiopatologia , Criança , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Imageamento Tridimensional , Ossos Pélvicos/fisiopatologia , Radiografia , Sacro/diagnóstico por imagem , Sacro/fisiopatologia , Escoliose/fisiopatologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiopatologia , Fatores de Tempo
6.
Scoliosis ; 9: 4, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24782912

RESUMO

This 2012 Consensus paper reviews the literature on side effects of x-ray exposure in the pediatric population as it relates to scoliosis evaluation and treatment. Alternative methods of spinal assessment and imaging are reviewed, and strategies for reducing the number of radiographs are developed. Using the Delphi technique, SOSORT members developed consensus statements that describe how often radiographs should be taken in each of the pediatric and adolescent sub-populations.

7.
PLoS One ; 8(8): e71504, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23977058

RESUMO

BACKGROUND: Vertebral wedging is associated with spinal deformity progression in adolescent idiopathic scoliosis. Reporting frontal and sagittal wedging separately could be misleading since these are projected values of a single three-dimensional deformation of the vertebral body. The objectives of this study were to determine if three-dimensional vertebral body wedging is present in mild scoliosis and if there are a preferential vertebral level, position and plane of deformation with increasing scoliotic severity. METHODOLOGY: Twenty-seven adolescent idiopathic scoliotic girls with mild to moderate Cobb angles (10° to 50°) participated in this study. All subjects had at least one set of bi-planar radiographs taken with the EOS® X-ray imaging system prior to any treatment. Subjects were divided into two groups, separating the mild (under 20°) from the moderate (20° and over) spinal scoliotic deformities. Wedging was calculated in three different geometric planes with respect to the smallest edge of the vertebral body. RESULTS: Factorial analyses of variance revealed a main effect for the scoliosis severity but no main effect of vertebral Levels (apex and each of the three vertebrae above and below it) (F = 1.78, p = 0.101). Main effects of vertebral Positions (apex and above or below it) (F = 4.20, p = 0.015) and wedging Planes (F = 34.36, p<0.001) were also noted. Post-hoc analysis demonstrated a greater wedging in the inferior group of vertebrae (3.6°) than the superior group (2.9°, p = 0.019) and a significantly greater wedging (p≤0.03) along the sagittal plane (4.3°). CONCLUSIONS: Vertebral wedging was present in mild scoliosis and increased as the scoliosis progressed. The greater wedging of the inferior group of vertebrae could be important in estimating the most distal vertebral segment to be restrained by bracing or to be fused in surgery. Largest vertebral body wedging values obtained in the sagittal plane support the claim that scoliosis could be initiated through a hypokyphosis.


Assuntos
Imageamento Tridimensional , Escoliose/patologia , Coluna Vertebral/patologia , Adolescente , Pontos de Referência Anatômicos , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/patologia , Radiografia , Escoliose/diagnóstico por imagem , Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/patologia
8.
PLoS One ; 8(7): e70205, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23875021

RESUMO

The purpose of this study was to determine how pelvic morphology, body posture, and standing balance variables of scoliotic girls differ from those of able-bodied girls, and to classify neuro-biomechanical variables in terms of a lower number of unobserved variables. Twenty-eight scoliotic and twenty-five non-scoliotic able-bodied girls participated in this study. 3D coordinates of ten anatomic body landmarks were used to describe pelvic morphology and trunk posture using a Flock of Birds system. Standing balance was measured using a force plate to identify the center of pressure (COP), and its anteroposterior (AP) and mediolateral (ML) displacements. A multivariate analysis of variance (MANOVA) was performed to determine differences between the two groups. A factor analysis was used to identify factors that best describe both groups. Statistical differences were identified between the groups for each of the parameter types. While spatial orientation of the pelvis was similar in both groups, five of the eight trunk postural variables of the scoliotic group were significantly different that the able-bodied group. Also, five out of the seven standing balance variables were higher in the scoliotic girls. Approximately 60% of the variation is supported by 4 factors that can be associated with a set of variables; standing balance variables (factor 1), body posture variables (factor 2), and pelvic morphology variables (factors 3 and 4). Pelvic distortion, body posture asymmetry, and standing imbalance are more pronounced in scoliotic girls, when compared to able-bodied girls. These findings may be beneficial when addressing balance and ankle proprioception exercises for the scoliotic population.


Assuntos
Pelve/anatomia & histologia , Equilíbrio Postural , Escoliose/fisiopatologia , Adolescente , Análise de Variância , Feminino , Humanos
9.
Med Eng Phys ; 35(11): 1607-12, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23777637

RESUMO

Anthropometric tables are not applicable to calculate the scoliotic trunk mass and center of mass (COM). The purposes of this study were: (1) to estimate the head and trunk mass and COM in able-bodied and scoliotic girls using a force plate method, (2) to estimate head and trunk COM offset compared to those of the body, and (3) the use of mean ratios to estimate the head and trunk COM calculated in this study and that calculated according to a conventional three-dimensional (3D) method compared to the measured values. Twenty-one scoliotic and twenty able-bodied girls participated. The subjects stood upright with arms beside the trunk on a force plate that collected data at 60 Hz for a period of 5s. The anteroposterior and mediolateral positions of the body COM were obtained from the mean center of pressure values. The height of the body COM was estimated by the reaction board method. Afterwards a body segment was displaced and changes in force plate readings were recorded and applied to estimate the head and trunk mass and COM. Trunk offset was defined as the difference between the COM of the body and head and trunk. The measured head and trunk COM was compared to values obtained by the mean ratios calculated from this study and given by the conventional 3D method. The relative head and trunk mass and the anteroposterior trunk offset were larger in scoliotic girls. The force plate method gave similar results to measured COM values for both groups underlying its capability to provide a more accurate estimation of COM related values. Thus, the use of mean ratios of 0.5538 and 0.6438 obtained in this study to estimate the head and trunk mass and COM position in scoliotic girls can overcome the main drawbacks of current anthropometric methods, if direct measurements cannot be taken.


Assuntos
Cabeça/anatomia & histologia , Cabeça/patologia , Fenômenos Mecânicos , Escoliose/patologia , Tronco/anatomia & histologia , Tronco/patologia , Estudos de Casos e Controles , Feminino , Humanos , Risco
10.
PLoS One ; 7(7): e36755, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22792155

RESUMO

Adolescent idiopathic scoliosis (AIS) is the most common form of scoliosis and usually affects young girls. Studies mostly describe the differences between scoliotic and non-scoliotic girls and focus primarily on a single set of parameters derived from spinal and pelvis morphology, posture or standing imbalance. No study addressed all these three biomechanical aspects simultaneously in pre-braced AIS girls of different scoliosis severity but with similar curve type and their interaction with scoliosis progression. The first objective of this study was to test if there are differences in these parameters between pre-braced AIS girls with a right thoracic scoliosis of moderate (less than 27°) and severe (more than 27°) deformity. The second objective was to identify which of these parameters are related to the Cobb angle progression either individually or in combination of thereof. Forty-five scoliotic girls, randomly selected by an orthopedic surgeon from the hospital scoliosis clinic, participated in this study. Parameters related to pelvis morphology, pelvis orientation, trunk posture and quiet standing balance were measured. Generally moderate pre-brace idiopathic scoliosis patients displayed lower values than the severe group characterized by a Cobb angle greater than 27°. Only pelvis morphology and trunk posture were statistically different between the groups while pelvis orientation and standing imbalance were similar in both groups. Statistically significant Pearson coefficients of correlation between individual parameters and Cobb angle ranged between 0.32 and 0.53. Collectively trunk posture, pelvis morphology and standing balance parameters are correlated with Cobb angle at 0.82. The results suggest that spinal deformity progression is not only a question of trunk morphology distortion by itself but is also related to pelvis asymmetrical bone growth and standing neuromuscular imbalance.


Assuntos
Ossos Pélvicos/patologia , Postura , Escoliose/patologia , Adolescente , Criança , Feminino , Humanos , Escoliose/diagnóstico , Escoliose/etiologia , Coluna Vertebral
11.
Scoliosis ; 7(1): 3, 2012 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-22264320

RESUMO

BACKGROUND: The International Scientific Society on Scoliosis Orthopaedic and Rehabilitation Treatment (SOSORT), that produced its first Guidelines in 2005, felt the need to revise them and increase their scientific quality. The aim is to offer to all professionals and their patients an evidence-based updated review of the actual evidence on conservative treatment of idiopathic scoliosis (CTIS). METHODS: All types of professionals (specialty physicians, and allied health professionals) engaged in CTIS have been involved together with a methodologist and a patient representative. A review of all the relevant literature and of the existing Guidelines have been performed. Documents, recommendations, and practical approach flow charts have been developed according to a Delphi procedure. A methodological and practical review has been made, and a final Consensus Session was held during the 2011 Barcelona SOSORT Meeting. RESULTS: The contents of the document are: methodology; generalities on idiopathic scoliosis; approach to CTIS in different patients, with practical flow-charts; literature review and recommendations on assessment, bracing, physiotherapy, Physiotherapeutic Specific Exercises (PSE) and other CTIS. Sixty-five recommendations have been given, divided in the following topics: Bracing (20 recommendations), PSE to prevent scoliosis progression during growth (8), PSE during brace treatment and surgical therapy (5), Other conservative treatments (3), Respiratory function and exercises (3), Sports activities (6), Assessment (20). No recommendations reached a Strength of Evidence level I; 2 were level II; 7 level III; and 20 level IV; through the Consensus procedure 26 reached level V and 10 level VI. The Strength of Recommendations was Grade A for 13, B for 49 and C for 3; none had grade D. CONCLUSION: These Guidelines have been a big effort of SOSORT to paint the actual situation of CTIS, starting from the evidence, and filling all the gray areas using a scientific method. According to results, it is possible to understand the lack of research in general on CTIS. SOSORT invites researchers to join, and clinicians to develop good research strategies to allow in the future to support or refute these recommendations according to new and stronger evidence.

12.
Eur Spine J ; 21(4): 725-32, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22083838

RESUMO

PURPOSE: To identify pelvic rotation and/or distortion in able-bodied and untreated AIS girls with moderate and severe scoliosis and verify association of pelvic morphological changes with Cobb angle increase. METHODS: The 3D coordinates of nine anatomic bony landmarks were identified to estimate pelvic orientation using a Flock of Birds system. The distances between the first sacral vertebral body (S1) and each of the eight iliac spine landmarks in all three planes were calculated to identify pelvic distortion. Analysis of variance was used to assess pelvic orientation and determine pelvic distortion. Pearson coefficients of correlation were used to identify any relationships between Cobb angle and pelvic morphological parameters. RESULTS: Pelvic orientation was similar in able-bodied and scoliotic girls regardless of the severity of the spinal deformity. Significant differences were observed in pelvic morphology between AIS with severe untreated scoliosis and those with a moderate scoliosis for the right anterosuperior iliac spines (ASIS), the tip of the superior iliac crest (TSIC) and the widest tip of the iliac crest (WTIC) widths from S1. Statistically significant correlations were observed between the Cobb angles and the iliac crest distances measured from S1. CONCLUSIONS: Differences in iliac spine geometries occurred in the transverse plane correlating to Cobb angles which suggest altered bone growth in AIS girls. Such findings could indicate right thoracic spinal deformity as a result of pelvic torsion.


Assuntos
Ílio/patologia , Escoliose/patologia , Índice de Gravidade de Doença , Curvaturas da Coluna Vertebral/patologia , Adolescente , Análise de Variância , Fenômenos Biomecânicos , Criança , Fenômenos Eletromagnéticos , Feminino , Humanos , Imageamento Tridimensional
13.
Scoliosis ; 5: 25, 2010 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-21067608

RESUMO

INTRODUCTION: Juvenile idiopathic scoliosis is a condition used to describe patients who are least 4 years of age but younger than 10 when the deformity is first identified. In these patients, the condition is usually progressive and those that are diagnosed at five years or younger have a high chance of progression to a large curve, with additional pulmonary and cardiac complications. The main form of conservative treatment for juvenile scoliosis is the use of a bracing system. This prospective interventional study was conducted to evaluate the effectiveness of the Dynamic SpineCor orthosis for juvenile idiopathic scoliosis as well as to evaluate the stability of the spine after the weaning point. MATERIAL AND METHODS: For this study, 150 juvenile patients were treated by the SpineCor orthosis between 1993 and 2009. Of these, 67 patients had a definite outcome and 83 are still actively being treated. To determine the effectiveness of the brace the OUTCOME criteria recommended by the SRS was used. RESULTS: The results from our study showed that of the 67 patients with a definite outcome, 32.9% corrected their Cobb angle by at least 5° and 10.5% had a stabilization of their Cobb angle. Within the patients with a definite outcome, 37.3% of patients where recommended for surgery before authorized end of treatment. For this group of patients, surgery was postponed. Looking at the stability of the curves 2 years after the end of the treatment, we found 12.5% of the patients continued their correction without the brace being used and 71.4% remained stable. DISCUSSION: From our study we can clearly see that the effectiveness of the SpineCor orthosis in obtaining and maintaining the neuromuscular integration of the corrective movement can be achieved effectively for juvenile patients. Over 75% of all patients that finished the treatment had remained stable with a few continuing to correct their Cobb angle after the use of the SpineCor orthosis was discontinued. CONCLUSION: Our conclusion from this study is that the SpineCor orthosis is a very effective method of treatment of juvenile idiopathic scoliosis. The results obtained also indicate that treatment outcomes are better with early bracing. Most encouraging perhaps is the fact that the positive outcome appears to be maintained in the long term, and that surgery can be avoided or at least postponed.

14.
Am J Phys Med Rehabil ; 89(10): 809-16, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20855981

RESUMO

OBJECTIVES: The purposes of this study are to assess the relationship of the center of pressure (CoP) displacement parameters along the mediolateral and anteroposterior axes to whole-body oscillations about the vertical axis during single or double leg upright stance and to determine whether sensory deprivation and stance modify balance stability about the vertical axis and in the horizontal plane. DESIGN: Eleven male adults stood on a force plate during conditions in which stance (single/double) and/or vision (normal/reduced) were modified independently. The dependent variables were CoP range, CoP velocity, and free moment (TZ) range. R-squared coefficients (R) were applied to assess the relationship between CoP and TZ range, whereas multifactor analysis of variances were used to assess the differences among conditions. RESULTS: R between CoP and TZ parameters varied from 0.16 to 0.69 for three of the four conditions, suggesting that different postural mechanisms controlled CoP displacements and body axial rotations. Single leg stance with reduced vision condition revealed a higher R between CoP velocity and TZ range. TZ range was approximately seven times greater when stance was modified to single limb stance, whereas reduced vision had no effect. CONCLUSIONS: Postural control mechanisms seem to be different for the free moment (TZ) than for the CoP displacements.


Assuntos
Perna (Membro)/fisiologia , Equilíbrio Postural/fisiologia , Postura/fisiologia , Baixa Visão/fisiopatologia , Suporte de Carga/fisiologia , Adulto , Tornozelo , Quadril , Humanos , Cinestesia/fisiologia , Masculino , Movimento/fisiologia , Tórax , Vibração , Baixa Visão/complicações , Adulto Jovem
15.
Spine (Phila Pa 1976) ; 35(13): E601-8, 2010 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-20461030

RESUMO

STUDY DESIGN: A cell-based assay was developed to identify asymptomatic children at risk of developing idiopathic scoliosis (IS) and to stratify IS patients at an earlier stage in order to better predict their clinical outcome. Clinical validation of this assay was performed by testing IS patients at different stages, healthy control subjects, and asymptomatic offspring, born from at least one scoliotic parent, who are considered at risk of developing this disorder. OBJECTIVE: Our goal was to develop and validate a clinical test for IS using cellular dielectric spectroscopy (CDS) and peripheral blood mononuclear cells (PBMCs). SUMMARY OF BACKGROUND DATA: We have previously demonstrated the occurrence of a melatonin signaling dysfunction in osteoblasts obtained from severely affected IS patients using a cAMP assay. This led us to stratify IS patients into 3 functional subgroups. METHODS: A group of 44 patients with IS was compared with 42 healthy control subjects and 31 asymptomatic at-risk children. PBMCs were obtained after centrifugation on a Ficoll-gradient. Melatonin signal transduction was measured by CDS in the presence of varying concentrations of melatonin or iodomelatonin. RESULTS: Osteoblasts from distinct functional subgroups were retested using CDS, allowing their classification into the same functional subgroups with both ligands as initially demonstrated using a cAMP assay. Clinical data obtained with CDS and PBMCs showed 100% specificity and 100% sensitivity because melatonin signaling impairment was observed only in IS patients and not in healthy controls. Assessment of the risk of developing a scoliosis in asymptomatic children was determined by CDS in 33% of asymptomatic children at risk, which was confirmed clinically within 24 months. CONCLUSION: This cell-based assay can serve as a presymptomatic screening test to identify asymptomatic children at risk of developing IS and may be used to improve stratification of patients, which in turn allow clinicians to predict their clinical outcome. Moreover, this functional blood test is advantageous because it can be performed without prior knowledge of specifically mutated genes causing IS.


Assuntos
AMP Cíclico/metabolismo , Leucócitos Mononucleares/metabolismo , Escoliose/diagnóstico , Análise Espectral/métodos , Adolescente , Células Cultivadas , Criança , Pré-Escolar , Diagnóstico Precoce , Técnicas Eletroquímicas/métodos , Feminino , Humanos , Leucócitos Mononucleares/citologia , Masculino , Programas de Rastreamento/métodos , Osteoblastos/citologia , Osteoblastos/metabolismo , Prognóstico , Escoliose/sangue , Sensibilidade e Especificidade , Adulto Jovem
16.
Eur Spine J ; 18(1): 38-44, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19066989

RESUMO

The aim of this study was to test the hypothesis that imbalance in patients with a severe deformity of the spine is associated with an increase in the sensory integration disorder. This paper is a case comparison study. Patients were divided into three groups: able-bodied (n = 53), observation (n = 23), and pre-brace (n = 26) groups. Time domain parameters (sway area, position and displacement) and structural posturographic parameters [mean distance (MD) and mean peak (MP)] were calculated from the COP excursion using a force platform. A sensory integration disorder could be an important factor in the progression of the scoliotic curve. Significant differences were found in time domain between observation, pre-brace and able-bodied groups. The results for the structural posturographic parameters showed significant differences between the pre-brace and the able-bodied groups (P = 0.018 MD and P = 0.02 MP) demonstrating a perturbation in sensory integration system by an increase of imbalance. The absence of statistical difference between the observation and the pre-brace groups for the structural posturographic parameters indicates a perturbation of sensory integration system associated with curve progression. Our study has demonstrated that the pre-brace group is less stable than the able-bodied group. The severity of scoliosis in pre-brace scoliotic girls could be related to an increase in the sensory integration disorder.


Assuntos
Postura/fisiologia , Escoliose/complicações , Transtornos de Sensação/complicações , Adolescente , Criança , Progressão da Doença , Feminino , Humanos
18.
Am J Orthop (Belle Mead NJ) ; 37(4): E78-83, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18535685

RESUMO

We evaluated the ability of a porous metallic interbody fusion implant made with porous nitinol (PNT) to achieve intervertebral fusion and the capacity of stabilization at the implantation site 3, 6, and 12 months after implantation. Sixteen sheep each received 1 PNT implant and 1 titanium (TiAIV) cage at intervertebral lumbar levels L2-L3 and L4-L5; 3 other sheep were used as untreated controls. The TiAIV cage was used as a control implant. After animal sacrifice, computed tomography was used to study peri-implant bone mineral density (BMD), and histologic slices were used to evaluate implant osseointegration. BMD around PNT implants was close to physiological (control value) BMD, whereas BMD around TiAIV cages was usually higher (sclerosis) than physiological BMD. Histologic analysis showed better osseointegration with PNT implants than with TiAIV cages. Sclerosis might result from bone acting to stabilize implants in their implantation sites. Compared with PNT implants, TiAIV cages seemed to be unstable in their implantation sites. For PNT implants, osseointegration was successful, and surrounding BMD was close to physiologic BMD.


Assuntos
Densidade Óssea , Próteses e Implantes , Fusão Vertebral/instrumentação , Ligas , Animais , Materiais Biocompatíveis , Feminino , Teste de Materiais , Osseointegração , Porosidade , Desenho de Prótese , Ovinos , Fusão Vertebral/métodos , Titânio , Tomografia Computadorizada por Raios X
19.
Disabil Rehabil Assist Technol ; 3(3): 112-9, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18465393

RESUMO

PURPOSE: To evaluate the change in spinal curvature and posture of Idiopathic Scoliosis patients when a curve specific 'Corrective Movement Principle' (CMP) is applied. METHODS: This prospective interventional study was carried out on a group of 639 patients (92.3% females) having idiopathic scoliosis treated with the SpineCor brace. All girls were premenarchal or less than 1 year postmenarchal. Assessment of brace effectiveness followed the SRS outcome criteria for bracing. The clinical, radiological and postural evaluations assisted to define the patient classification, which guided the unique application of the CMP to each type of curvature. RESULTS: A total of 583 patients met the outcome criteria. Overall, 349 patients have a definitive outcome. Successful treatment was achieved in 259 (74.2%) of the 349 patients from the fitting to the weaning of the brace. Some 51 immature patients (14.6%) required surgical fusion while receiving treatment. Eight mature patients out of 298 (2.7%) required surgery within 2 years of follow-up beyond skeletal maturity. CONCLUSION: The SpineCor brace is effective for the treatment of adolescent idiopathic scoliosis. Moreover, positive outcomes are maintained after 2 years because 151 (93.2%) of 162 patients stabilized or corrected their end of bracing Cobb angle up to 2 years after bracing.


Assuntos
Braquetes , Escoliose/terapia , Adolescente , Fatores Etários , Criança , Pré-Escolar , Desenho de Equipamento , Feminino , Humanos , Masculino , Estudos Prospectivos , Escoliose/reabilitação , Resultado do Tratamento
20.
J Pediatr Orthop ; 28(2): 218-24, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18388718

RESUMO

BACKGROUND: The objectives of this study were to compare the postural characteristics of idiopathic scoliosis (IS) patients with different types of spinal curvature and to compare a motion capture and a sequential digitization technique to estimate the postural characteristics of the IS patients. METHODS: A total of 57 IS patients underwent a radiological, clinical, and postural geometric evaluations in an upright standing position as part of their regular follow-up. The posteroanterior radiograph of the trunk was used to measure the amplitude of spinal curvature. The postural evaluation was performed using a motion capture and sequential digitization technique providing the necessary 3-dimensional positions of anatomical landmarks. These landmarks were used to calculate postural parameters defining the position and orientation of the pelvis, shoulders, and shoulder blades. These measurements included lateral shift and angular measures of rotation and tilt. RESULTS: Significant differences in the frontal and transverse planes were found between the right thoracic (RTh), left thoracolumbar, and RTh-left lumbar (RThLL) patients. These characteristics were most prominent in the transverse plane for RTh patients, in the frontal plane for left thoracolumbar patients, and in the frontal and transverse planes for the RThLL lumbar patients. A strong positive intraclass correlation was also found between the parameters estimated with the motion capture system and with the sequential digitization system. CONCLUSIONS: Unique postural characteristics that are related to the type of the spinal curvature are evident in adolescents who have IS. Further work is necessary to assess how these measures may be used to monitor the progression of the spinal deformity. CLINICAL RELEVANCE: Quantifying the postural alignment of IS patients using surface anthropometric landmarks provides an opportunity to characterize the unique postural attributes that accompany each type of spinal curvature.


Assuntos
Imageamento Tridimensional/métodos , Postura/fisiologia , Escoliose/fisiopatologia , Adolescente , Antropometria , Fenômenos Biomecânicos , Humanos , Movimento/fisiologia , Estudos Prospectivos , Radiografia , Escoliose/diagnóstico por imagem
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