Radiation-free quantitative assessment of scoliosis: a multi center prospective study

Accuracy of photogrammetry for detecting adolescent idiopathic scoliosis progression

BACKGROUND

The gold standard method of monitoring the evolution of scoliosis has been serial standing, posteroanterior, full-length spine radiographs with curvature measurements using the Cobb method. However, over the course of follow-up, patients can receive high radiation doses. Various studies have shown that repeated exposure to radiation in children and adolescents can be harmful to their health.

PURPOSE

To determine the accuracy of photogrammetry in evaluating the progression of adolescent idiopathic scoliosis in comparison with radiography.

STUDY DESIGN

Diagnostic study.

PATIENT SAMPLE

Ninety adolescents subjected to radiographic follow-up of idiopathic scoliosis.

OUTCOME MEASURES

The angle of scoliotic curvature was measured using the Cobb radiographic method and photogrammetry. An increase of 5° or more between two radiographic exams was considered a progression of the curvature and was defined as the standard for calculations of sensitivity, specificity, predictive value, and accuracy of the photogrammetric method for measuring scoliosis progression.

METHODS

Patients were subjected to radiographic and photogrammetric exams concomitantly and were reevaluated after an average of 8.6 months. The exams were analyzed separately and independently by two examiners for progression of scoliosis.

RESULTS

The measurements of the curves at the beginning of the study were 39.5±16.7° and 39.5±14.3° for radiographic and photogrammetric exams, respectively (p=1.0). At the end of the study, the measurements of the curves were 40.2±16.2° and 41.3±15.1° for the radiographic and photogrammetric exams, respectively (p=.310). The photogrammetric method had an accuracy of 89% (Confidence interval [CI] 95%=82.5-95.5) for the detection of scoliosis progression, with a sensitivity of 94.4% (CI 95%=89.6-99.2), a specificity of 86.7% (CI 95%=79.7-93.7), a positive predictive value of 75.5% (CI 95%=66.6-84.4), a negative predictive value of 97.2% (CI 95%=93.8-100), and a Kappa index of 0.75 (CI 95%=66.1-83.9). The interclass correlation coefficient between the two methods was 0.74 (CI 95%=0.65-0.81; p=0).

CONCLUSIONS

The photogrammetric method showed good performance for detecting the progression of adolescent idiopathic scoliosis in comparison with the radiographic exam method.

Clinical application of back surface topography by means of structured light in the screening of idiopathic scoliosis

We present the results of the clinical validity in the screening of idiopathic scoliosis with a nonharming method of back surface topography by means of structured light projection. A total of 155 patients were evaluated (mean age 13.3 years). They were divided into two groups: pathologic patients (scoliosis) and nonpathologic patients (control and asymmetries). An analytical case-control study was carried out. Our topographic method obtained 92% sensitivity and 74% specificity as a screening test in identifying patients with scoliosis (P=0.05). We could quantify the vertebral deformity of scoliosis in the three spatial planes by means of three topographic variables, Horizontal Plane Deformity Index, Posterior Trunk Symmetry Index and Columnar Profile, and to elaborate a combined screening algorithm with good reliability parameters.

Longitudinal Pilot Analysis of Radiation Exposure During the Course of Growing Rod Treatment for Early-Onset Scoliosis

STUDY DESIGN

Retrospective consecutive case series.

OBJECTIVES

To estimate the amount of ionizing radiation (IR) exposure in growing rod (GR) surgery for early-onset scoliosis.

SUMMARY OF BACKGROUND DATA

There is substantial evidence of the health hazards attributed to IR exposure. However, no studies have estimated the amount of IR exposure in GR surgery.

MATERIALS AND METHODS

A consecutive single-center series of GR patients were retrospectively reviewed. Of 28 total patients, 24 had a minimum 2-year follow-up and complete records available for analysis. All spine-related IR imaging studies excluding intraoperative fluoroscopy were tabulated and IR estimated based on historical controls in millisieverts (mSv).

RESULTS

Initial x-ray evaluation for scoliosis was performed at a mean age of 4.0 years (range = birth to 9.7). Mean radiographic period was 8.5 years (range = 2.2 to 19.4). There was a statistically significant inverse correlation between patient age at time of initial IR and total mean IR (p < .05). Total IR was 3.4 times greater than that of estimated background radiation (2.4 mSv per year). Mean IR before index surgery and during the first postoperative year were 22.41 mSv and 10.78 mSv, respectively. Annual IR after the first postoperative year averaged 7.02 mSv (range = 2.25 to 13.45). Patients who underwent at least one revision surgery experienced significantly higher IR than nonrevision patients (79.95 vs. 46.58 mSv; p < .05). Overall, 89% of total IR was attributed to x-rays and 11% from computed tomography.

CONCLUSIONS

Compared to the general public, GR patients had 3.4 times more IR than the estimated background radiation for the same duration of time. Younger patients and those requiring revision surgery had significantly higher IR doses. This study underscores the importance of recognizing the amount of IR used in the management of GR patients and its potential long-term risks.

LEVEL OF EVIDENCE

III.

Correlation Between a Novel Surface Topography Asymmetry Analysis and Radiographic Data in Scoliosis

STUDY DESIGN

Cross-sectional study.

OBJECTIVE

To investigate the correlation between parameters extracted from a three-dimensional (3D) asymmetry analysis of the torso and the internal deformities of the spine presented on radiographs, including 1) curve number, direction and location; 2) location of the apical vertebra; and 3) curve severity.

SUMMARY OF BACKGROUND DATA

Surface topography (ST) is used to assess external torso deformities and may predict important characteristics of the underlying spinal curves. ST does not expose patients to radiation and could safely be used clinically for scoliosis patients. Most ST indices rely on anatomical landmarks on the torso and 2D measurements.

METHODS

The ability of a 3D markerless asymmetry technique to predict radiographic characteristics was assessed for 100 scoliosis patients with full torso ST scans. Twenty-four additional patients were used for validation. The number, direction, and location of curves were determined by three examiners using ST deviation color maps. The inter-method percentage of agreement and Kappa coefficient were estimated for each measure. Linear regression predicted the vertical location of the apical vertebra from ST. Curve severity (mild, moderate, severe) was predicted with a decision tree analysis using ST parameters.

RESULTS

The average percentage of agreement was 62%, 66%, and 23% for single, double, and triple curves, respectively. Curve direction was always correctly identified. The average percentages of agreement for curve location were 63%, 92%, and 62% for proximal thoracic, thoracic/thoracolumbar (T-TL), and lumbar (L) curves, respectively. Apical vertebra location was predicted with R² = 0.89 for T-TL and R² = 0.58 for L curves. ST parameters classified curve severity for T-TL and L curves with 73% and 59% accuracy, respectively.

CONCLUSIONS

The method presented here improves upon current ST techniques by using the entire torso surface and both a visual and quantitative representation of the asymmetry to better capture the torso deformity.

Comparison of parameters characterizing lumbar lordosis in radiograph and photogrammetric examination of adults

OBJECTIVE

The purpose of this study was to test validity of photogrammetry compared with radiography as a method of measuring the Cobb angle and the size of anterior-posterior spine curvatures in adults.

METHODS

The study included 50 volunteers, 23 men and 27 women whose mean age was 52.6 years. The average weight of the subjects was 81.3 kg, average body height was 172.0 cm, and the average body mass index was 27.4. Based on radiologic examination, the length and depth of lumbar lordosis were determined and the size of the Cobb angle of lumbar scoliosis. After the radiologic examination, a photogrammetric test was performed for each subject with the projection moire phenomenon.

RESULTS

The Pearson correlation found statistically significant associations concerning the length of lordosis (P < .001) and the Cobb angle (P < .001). Correlation of the depth of lordosis indicated a strong trend (P = .063).

CONCLUSIONS

This study found that the moire method of photogrammetric measurement produced similar findings to radiographic measurements in determining size of the Cobb angle and the length of lumbar lordosis.

Assessing kyphosis with SpineScan: another attempt to reduce our dependence on radiography

BACKGROUND CONTEXT

Kyphosis management is mainly conservative, with annual examinations to assess angular progression. This includes physical examination and usually long spine X-rays, notorious for ionizing radiation. Several nonradiological instruments have been devised for this, but none have become popular. SpineScan, a programmed digital inclinometer, has been proved effective for screening kyphoscoliosis.

PURPOSE

The aim of this study was to assess the accuracy of SpineScan in monitoring kyphosis.

STUDY DESIGN/SETTING

Prospective, observational, diagnostic accuracy study.

PATIENT SAMPLE

Twenty-eight subjects examined for kyphosis, with recent full-length lateral spine X-rays.

METHODS

Each subject was examined by two examiners. The technique involved the subject standing with arms flexed to 90° and then sliding the SpineScan from just below C7 to L2. Maximum X-ray kyphotic Cobb angle was compared with the SpineScan result. The study was institutional review board approved, and all patients signed an informed consent.

RESULTS

The mean Cobb angle of the 28 subjects on radiography was 51° ± 15°. The mean SpineScan angle of all trials of all examiners was 54° ± 12°. The difference between the two measurements was significantly different from zero (3.2° ± 9.4°, p<.0001) and not normally distributed. The difference was significantly affected by the Cobb angle, examiner, and interaction between Cobb and examiner (statistical significance for all p<.0001). Ninety-five percent confidence intervals for all examiners ranged between -16° and 22° and for separate examiners between -25° and 32°, far above the 5° preplanned error level.

CONCLUSIONS

The results demonstrated that there is significant error in monitoring kyphosis with SpineScan. Even for a more modest indication including replacing radiography with SpineScan on alternate visits, the measurement was not accurate enough. Future research is necessary to find a nonradiographic method of kyphosis follow-up, possibly using a digitalized modification of one of the described instruments.

Influência de calços na orientação postural de indivíduos com escoliose idiopática

INTRODUÇÃO: A relação entre a orientação dos segmentos e os ajustes que podem ser desencadeados por calços e palmilhas em pacientes escolióticos durante a manutenção da posição ortostática é pouco conhecida. OBJETIVO: Verificar alterações estáticas e associadas com mudanças unilaterais de calços na orientação postural de indivíduos com escoliose idiopática. MATERIAIS E MÉTODOS: Grupo experimental com dez indivíduos com escoliose idiopática com curva dupla (menor 10°) e grupo controle com dez indivíduos sem escoliose (faixa etária de 13 a 24 anos). Participantes foram filmados na posição ortostática sem calço, com calço baixo (1 cm) e com calço alto (3 cm); estes foram colocados sob o pé direito e pé esquerdo dos indivíduos. Em cada condição, o participante manteve a posição estática durante 15 segundos e marcadores refletivos foram colocados em pontos anatômicos específicos. Foram calculados ângulos posturais: torácico alto; torácico médio; toracolombar e lombar e ângulos segmentares: ombro; escápula; pelve e joelho. RESULTADOS: Na condição sem calço, diferenças foram observadas entre grupos para os ângulos posturais toracolombar e lombar e para o ângulo segmentar do ombro. Com calço baixo e alto, sob o pé direito, diferença foi observada entre calços para os ângulos lombar, da pelve e do joelho. Com calço baixo e alto, sob o pé esquerdo, diferença foi observada entre grupos para o ângulo toracolombar e entre calços para os ângulos da pelve e do joelho. CONCLUSÕES: A utilização de calço promove reorientação nas regiões mais baixas da coluna e nos segmentos da pelve e do joelho. Estes resultados sugerem que nas escolioses duplas, manipulação da base de apoio modifica o alinhamento do tronco que pode provocar reorganização das estruturas e busca de um novo arranjo entre segmentos em indivíduos com escoliose idiopática.

A pilot study of scoliosis assessment using radiation free surface topography in children with GMFCS IV and V cerebral palsy

BACKGROUND

Prevalence of scoliosis in cerebral palsy (CP) parallels the extent of neurological impairment and causes significant morbidity. Monitoring is important but requires regular radiological investigation. Surface topography provides a non-radiological approach to scoliosis monitoring.

AIM

To evaluate validity, reproducibility and feasibility of Quantec(®) scans to monitor scoliosis in children with severe CP.

METHODS

Twenty non-ambulant children with CP, Gross Motor Function Classification System (GMFCS) grade IV/V had clinical, radiological and Quantec spinal assessment. The children were supported during scans using a seating system specifically designed for this study. Validity was assessed by comparing Quantec (Q) angle with gold standard (Cobb angle), reproducibility analysed using Bland-Altman plots and feasibility assessed using a questionnaire.

RESULTS

Prevalence of scoliosis on radiological examination was 65%. Of these children, 85% had curves with Cobb angle less than 28°. Quantec scanning was feasible with appropriate postural support. Mean (and standard deviation) for differences between Cobb and Quantec (Q) angle were 0.02° (6.2°) and for Quantec inter-observer variability were 0.5° (5.8°).

CONCLUSIONS

Quantec scanning was feasible, reproducible and had good validity when compared with Cobb angle in a supportive seating system. To consolidate these findings a further study needs to be undertaken with larger number of children with Cobb angles between 25° and 45°.

Optimization of the examination posture in spinal curvature assessment

To decrease the influence of postural sway during spinal measurements, an instrumented fixation posture (called G) was proposed and tested in comparison with the free standing posture (A) using the DTP-3 system in a group of 70 healthy volunteers. The measurement was performed 5 times on each subject and each position was tested by a newly developed device for non-invasive spinal measurements called DTP-3 system. Changes in postural stability of the spinous processes for each subject/the whole group were evaluated by employing standard statistical tools. Posture G, when compared to posture A, reduced postural sway significantly in all spinous processes from C3 to L5 in both the mediolateral and anterioposterior directions. Posture G also significantly reduced postural sway in the vertical direction in 18 out of 22 spinous processes. Importantly, posture G did not significantly influence the spinal curvature.

New method of scoliosis assessment: preliminary results using computerized photogrammetry

STUDY DESIGN

A new method for nonradiographic evaluation of scoliosis was independently compared with the Cobb radiographic method, for the quantification of scoliotic curvature.

OBJECTIVE

To develop a protocol for computerized photogrammetry, as a nonradiographic method, for the quantification of scoliosis, and to mathematically relate this proposed method with the Cobb radiographic method.

SUMMARY OF BACKGROUND DATA

Repeated exposure to radiation of children can be harmful to their health. Nevertheless, no nonradiographic method until now proposed has gained popularity as a routine method for evaluation, mainly due to a low correspondence to the Cobb radiographic method.

METHODS

Patients undergoing standing posteroanterior full-length spine radiographs, who were willing to participate in this study, were submitted to dorsal digital photography in the orthostatic position with special surface markers over the spinous process, specifically the vertebrae C7 to L5. The radiographic and photographic images were sent separately for independent analysis to two examiners, trained in quantification of scoliosis for the types of images received. The scoliosis curvature angles obtained through computerized photogrammetry (the new method) were compared to those obtained through the Cobb radiographic method.

RESULTS

Sixteen individuals were evaluated (14 female and 2 male). All presented idiopathic scoliosis, and were between 21.4 ± 6.1 years of age; 52.9 ± 5.8 kg in weight; 1.63 ± 0.05 m in height, with a body mass index of 19.8 ± 0.2. There was no statistically significant difference between the scoliosis angle measurements obtained in the comparative analysis of both methods, and a mathematical relationship was formulated between both methods.

CONCLUSION

The preliminary results presented demonstrate equivalence between the two methods. More studies are needed to firmly assess the potential of this new method as a coadjuvant tool in the routine following of scoliosis treatment.

Reliability of photogrammetry in the evaluation of the postural aspects of individuals with structural scoliosis

PURPOSE

The purpose of this study was to investigate the reliability of photogrammetry in the measurement of the postural deviations in individuals with idiopathic scoliosis.

METHODS

Twenty participants with scoliosis (17 women and three men), with a mean age of 23.1 ± 9 yrs, were photographed from the posterior and lateral views. The postural aspects were measured with CorelDRAW software.

RESULTS

High inter-rater and test-retest reliability indices were found. It was observed that with more severity of scoliosis, greater were the variations between the thoracic kyphosis and lumbar lordosis measures obtained by the same examiner from the left lateral view photographs. A greater body mass index (BMI) was associated with greater variability of the trunk rotation measures obtained by two independent examiners from the right, lateral view (r = 0.656; p = 0.002). The severity of scoliosis was also associated with greater inter-rater variability measures of trunk rotation obtained from the left, lateral view (r = 0.483; p = 0.036).

CONCLUSIONS

Photogrammetry demonstrated to be a reliable method for the measurement of postural deviations from the posterior and lateral views of individuals with idiopathic scoliosis and could be complementarily employed for the assessment procedures, which could reduce the number of X-rays used for the follow-up assessments of these individuals.

Patient evaluation in idiopathic scoliosis: Radiographic assessment, trunk deformity and back asymmetry

Progressive adolescent idiopathic scoliosis (AIS) produces specific signs and symptoms, including trunk and spinal deformity and imbalance, impairment of breathing function, pain, progression during adult life, and psychological problems, as a whole resulting in an alteration of the health-related quality of life. A scoliosis-specific rehabilitation program attempts to prevent, improve, or minimize these signs and symptoms by using exercises and braces as the main tools in the rehabilitation treatment. Patient evaluation is an essential point in the decision-making process and determines the selection of the specific exercises and the specifications of the brace design. However, this article is not addressed to scoliosis management. In this present article, a complete definition and discussion of radiological aspects, such as the Cobb angle, axial rotation, curve pattern classifications, and sagittal configuration, follow a short description of the three-dimensional nature of AIS. The relationship between AIS and growth is also discussed. There is also a section dedicated to the assessment of trunk deformity and back asymmetry. Other important clinical aspects, such as pain and disability, changes in other regions of the body, muscular balance, breathing function, and health-related quality of life, are not discussed in this present article.

[Imaging of non-traumatic spinal diseases in children]

Pain is also the main symptom of spinal diseases in children. The younger the child, the more frequently organic causes are to be found, whereas in adolescents functional dorsalgia and lumbalgia are ubiquitous. Apart from the neonatal period, where ultrasound is used as the primary method for investigation of closed spinal dysraphia, radiography is still considered to be the first choice examination, which nevertheless should only be carried out after a thorough anamnesis and clinical examination. For targeted follow-up and especially exclusion of neoplasms, MRI is the method of choice in most cases. Computed tomography (CT) plays an important role preoperatively and postoperatively in corrective spine surgery and together with scintigraphy in the diagnostics of spondylolysis and some tumors such as osteoid osteoma. Important is the care of children with hereditary spinal malformations, especially dysraphias where the entire CNS may be affected as with the common association of myelomeningocele and Chiari II malformation with hydrocephalus and hydromyalia.

No effect of osteopathic treatment on trunk morphology and spine flexibility in young women with adolescent idiopathic scoliosis

INTRODUCTION

Brace treatment is the gold standard for patients with mild adolescent idiopathic scoliosis (Cobb angle 20°-40°). However, negative psychosocial impacts, physical constraints and incompliance cause many patients and parents to seek for so-called holistic and apparently less harmful approaches within the field of complementary and alternative medicine (CAM). Osteopathy-manual interventions on the viscera and locomotor system-is widely used for scoliosis. There is, however, a complete lack of evidence regarding its efficacy. We, therefore, tested the hypothesis that osteopathy alters trunk morphology, a prerequisite to unload the concave side of the scoliosis, and that it halts curve progression.

METHODS

This was a prospective, controlled trial of 20 post-pubertal young women (20°-40° idiopathic scoliosis) randomly allocated to an observation (group 0) or osteopathic treatment (group 1). The latter comprised three sessions (5 weeks). Trunk morphology (clinical examination, video rasterstereography) and spine flexibility (MediMouse(®)) were assessed at a pre- and post-intervention with a 3-month interval (blinded examiner). We chose scoliometer measurement (rib hump, lumbar prominence) as the main outcome parameter.

RESULTS

Two patients in the treatment group refused further treatment and the final examination, as they felt no benefit after two osteopathic treatments. Regression analysis for repeat measurements (independent statistician) revealed no therapeutic effect on rib hump, lumbar prominence, plumb line, sagittal profile and global spinal flexibility.

CONCLUSIONS

We found no evidence to support osteopathy in the treatment of mild adolescent idiopathic scoliosis. Therefore, we caution against abandoning the conventional standard of care for mild idiopathic scoliosis. As for other CAM therapies, the use of osteopathy as a treatment option for scoliosis still needs to be clearly defined.

Reliability and validity of the photogrammetry for scoliosis evaluation: a cross-sectional prospective study

OBJECTIVE

The purpose of this study was to investigate the reliability and validity of photogrammetry in measuring the lateral spinal inclination angles.

METHODS

Forty subjects (32 female and 8 males) with a mean age of 23.4 +/- 11.2 years had their scoliosis evaluated by radiographs of their trunk, determined by the Cobb angle method, and by photogrammetry. The statistical methods used included Cronbach alpha, Pearson/Spearman correlation coefficients, and regression analyses.

RESULTS

The Cronbach alpha values showed that the photogrammetric measures showed high internal consistency, which indicated that the sample was bias free. The radiograph method showed to be more precise with intrarater reliabilities of 0.936, 0.975, and 0.945 for the thoracic, lumbar, and thoracolumbar curves, respectively, and interrater reliabilities of 0.942 and 0.879 for the angular measures of the thoracic and thoracolumbar segments, respectively. The regression analyses revealed a high determination coefficient although limited to the adjusted linear model between the radiographic and photographic measures. It was found that with more severe scoliosis, the lateral curve measures obtained with the photogrammetry were for the thoracic and lumbar regions (R = 0.619 and 0.551).

CONCLUSIONS

The photogrammetric measures were found to be reproducible in this study and could be used as supplementary information to decrease the number of radiographs necessary for the monitoring of scoliosis.

Examination of the newborn with congenital scoliosis: focus on the physical

Although scoliosis at birth is rare, conditions at birth and in the newborn period predispose newborns to the development of scoliosis in later life. Scoliosis is congenital when associated with abnormal vertebral segmentation regardless of the age of diagnosis. Other conditions may predispose neonates to vertebral damage or the development of sustained uneven forces on the developing spine. Although it is difficult to know which newborns will progress to developing scoliosis, it is important to be aware of risk factors to provide anticipatory education for parents and to arrange appropriate follow-up after discharge. This article reviews the embryology of vertebral formation and risk factors for the development of scoliosis. The discussion includes the incidence, risk factors, genetics, associated problems, physical examination, and nursing implications of the infant with congenital scoliosis.