Trunk Growth in Early-Onset Idiopathic Scoliosis Measured With Biplanar Radiography

Study Design Cross-sectional and longitudinal retrospective study. Objectives To measure thoracic dimensions and volume during growth in early-onset idiopathic scoliosis (EOIS) patients and to compare them to a population of asymptomatic adults and to the previous literature. Summary of Background Data Data on trunk growth for scoliotic children between 6 and 14 years of age is sparse in the literature. Methods Thirty-six patients (29 girls and 7 boys, between 3 and 14 years old, average Cobb angle 33°±15°) were included, all with a minimum two-year follow-up. Sixty-one asymptomatic girls and 54 asymptomatic adults were included as control groups. All subjects underwent biplanar radiography and 3D reconstruction of the spine, pelvis, and rib cage. EOIS patients repeated their radiologic examination every six months. Cobb angle, rib cage volume, anteroposterior and transverse diameters, thoracic index, thoracic perimeter, pelvic incidence, and T1–T12 and T1–S1 distance were calculated. Reproducibility of measurement was assessed. Results Measurement reliability in such young patients was comparable to previous studies in adolescents and adults. Geometrical parameters of EOIS patients increased linearly with age. For instance, rib cage volume in girls with EOIS increased from 2200 cm3 at six to seven years of age to 4100 cm3 at 13–14 years (65% of adult values, 294 cm3/y). Comparison with asymptomatic girls showed that EOIS could affect growth spurt. Longitudinal analysis on a cohort of six girls who had a follow-up of six years confirmed the cross-sectional data. Conclusions In this longitudinal and cross-sectional study, trunk growth between 3 and 14 years of age was characterized, for the first time, with biplanar radiography and 3D reconstruction. The results can be useful to estimate patient growth and thus have potential application in the surgical planning of EOIS patients. Level of Evidence Level II, retrospective study

Repeatability and validation of Gait Deviation Index in children: Typically developing and cerebral palsy

The Gait Deviation Index (GDI) is a dimensionless parameter that evaluates the deviation of kinematic gait from a control database. The GDI can be used to stratify gait pathology in children with cerebral palsy (CP). In this paper the repeatability and uncertainty of the GDI were evaluated. The Correlation between the GDI and the Gross Motor Function Classification System (GMFCS) was studied for different groups of children with CP (hemiplegia, diplegia, triplegia and quadriplegia). Forty-nine, typically developing children (TD) formed our database. A retrospective study was conducted on our 3D gait data and clinical exams and 134 spastic children were included. Sixteen TD children completed the gait analysis twice to evaluate the repeatability of the GDI (test–retest evaluation). Monte Carlo simulations were applied for all groups (TD and children with CP) in order to evaluate the propagation of errors stemming from kinematics. The repeatability coefficient (2SD of test–retest differences), obtained on the GDI for the 16 TD children (32 lower limbs) was ±10. Monte Carlo simulations showed an uncertainty ranging between 0.8 and 1.3 for TD children and all groups with CP. The Spearman Rank correlation showed a moderate correlation between the GDI and the GMFCS (r = −0.44, p < 0.0001)

A new approach in the clinical decision-making for cerebral palsy using three-dimensional subject-specific musculoskeletal reconstructions.

Cerebral palsy (CP) is a neurological disorder which can cause muscular spasticity. Children with this condition suffer from a combination of gait deviations, skeletal deformities and muscular abnormalities. Precise evaluation of each of these three components is crucial for management planning in children with CP. The aim of this study is to review the latest innovative methods used for three-dimensional (3D) gait analysis and musculoskeletal modeling in children with cerebral palsy. 3D gait analysis is a quantitative objective method based on the use of infrared cameras. It allows the evaluation of dynamic joint angles, forces and moments applied on joints and is usually coupled with dynamic electromyography. Skeletal evaluation is usually based on two-dimensional X-rays and physical examination in clinical practice. However, a novel method based on stereoradiographic 3D reconstruction of biplanar low dose X-rays allows a more thorough evaluation of skeletal deformities, and in particular torsional anomalies. Muscular evaluation of children with CP is most commonly based on magnetic resonance imaging, whereby delimitation of lower limb muscles on axial slices allows 3D reconstruction of these muscles. Novel innovative techniques allow similar reconstructions by extrapolation, thus limiting the necessary quantity of axial slices that need to be manually delimitated.This study has been funded by the Research Council of Saint Joseph University (grant # FM 244) and the CEDRE project (grant N# 11 SCI F 44/L36)

Kinematic Evaluation of 4 Pediatric Collars and Distribution of Cervical Movement Between Primary and Coupled Angles

Background: Primary and coupled angle restrictions, when neck collars are used, have been investigated mainly in adults and not yet in children. Purpose: To evaluate the efficiency of 4 pediatric collars in reducing cervical range of motion (ROM) in primary and coupled planes. Methods: Thirty asymptomatic children (16 boys and 14 girls) aged 6 to 12 years participated in the study. A motion analysis system was used to evaluate the ROM of the cervical spine during flexion/extension, left and right lateral bending, and left and right axial rotation. Primary and coupled ROM were evaluated in unbraced and braced conditions. Four cervical collars were tested: Philadelphia, Miami Jr, Necloc, and the conventional Hard Collar. Thirteen subjects were tested 2 times to evaluate the repeatability of the parameters. The ROM in each plane was normalized to the sum of the ROM in the 3 planes, for each movement, to estimate the percentage of the movement in each plane (normalized ROM), in braced and unbraced conditions. The analysis of variance and post hoc Benferroni tests were applied on raw and normalized ROM. Results: ROM collected in collars showed a significant difference compared with the unbraced condition. ROM obtained in Necloc and Miami Jr showed a significant difference compared with Philadelphia and conventional Hard Collar. The primary plane is activated at 80% during flexion-extension and left-right axial rotation; however, 55% of the total movement was completed in the frontal plane during left-right lateral bending in unbraced condition. Statistical differences in the normalized ROM were found between the braced and unbraced conditions and among collars. Conclusions: Necloc and Miami Jr presented the highest limitation of movement in the primary and secondary planes. The distribution strategy of a movement, between primary and coupled angles, is different between the braced and unbraced conditions

Three dimensional kinematics of upper limb anatomical movements in asymptomatic adults: Dominant vs.non-dominant

The effect of dominance on upper limb (UL) kinematics has only been studied on scapular movements. Moreover, when an anatomical UL movement is performed in a specific plane, secondary movements in the remaining planes involuntarily occur. These secondary movements have not been previously evaluated. The aim of this study was to compare the kinematics of primary and secondary angles of dominant and non-dominant UL during anatomical movements in asymptomatic adults. 25 asymptomatic adults performed 6 anatomical movements bilaterally: shoulder flexion-extension, abduction-adduction, horizontal abduction-adduction, internal-external rotation, elbow flexion-extension and wrist pronation-supination. Kinematics of the dominant and non-dominant UL were compared by their ranges of motion (ROM) and their angular waveforms (Coefficient of Multiple Correlations, CMC). The comparison between dominant and non-dominant UL kinematics showed different strategies of movement, most notably during elbow flexion-extension (CMC = 0.29): the dominant UL exhibited more pronation at maximal elbow flexion. Significant secondary angles were found on most of the UL anatomical movements; e.g. a secondary ROM of shoulder (humero-thoracic) external-internal rotation (69° ± 16°) was found when the subject intended to perform maximal shoulder abduction-adduction (119° ± 21°). Bias of dominance should be considered when comparing pathological limb to the controlateral one. Normative values of primary and secondary angles during anatomical movements could be used as a reference for future studies on UL of subjects with neurological or orthopedic pathologies.This study was sponsored by the research council of the University of Saint-Joseph under the Grant number IPHY

Alterations of treatment-naïve pelvis and thigh muscle morphology in children with cerebral palsy

Lower limb (LL) muscle morphology and growth are altered in children with cerebral palsy (CP). Muscle alterations differ with age and with severity of motor impairment, classified according to the gross motor classification system (GMFCS). Muscle alterations differ also with orthopedic intervention, frequently performed at the level of the shank muscles since an early age, such as the gastrocnemius. The aim was to investigate the alterations of treatment-naïve pelvis and thigh muscle lengths and volumes in children with GMFCS levels I and II, of varying ages. 17 children with CP (GMFCS I: N = 9, II: N = 8, age: 11.7 ± 4 years), age-matched to 17 typically developing (TD) children, underwent MRI of the LL. Three-dimensional reconstructions of the muscles were performed bilaterally. Muscle volumes and lengths were calculated in 3D and compared between groups. Linear regression between muscle volumes and age were computed. Adductor-brevis and gracilis lengths, as well as rectus-femoris volume, were decreased in GMFCS I compared to TD (p < 0.05). Almost all the reconstructed muscle volumes and lengths were found to be altered in GMFCS II compared to TD and GMFCS I. All muscle volumes showed significant increase with age in TD and GMFCS I (R2 range: 0.3–0.9, p < 0.05). Rectus-femoris, hamstrings and adductor-longus showed reduced increase in the muscle volume with age in GMFCS II when compared to TD and GMFCS I. Alterations of treatment-naïve pelvis and thigh muscle volumes and lengths, as well as muscle growth, seem to increase with the severity of motor impairment in ambulant children with CP.This study was funded by the research council of the University of Saint-Joseph in Beirut (grant# FM244) and the CEDRE french-lebanese cooperation in academic research (grant# 11SCIF44/L36)

Validation of hip joint center localization methods during gait analysis using 3D EOS imaging in typically developing and cerebral palsy children

Localization of the hip joint center (HJC) is essential in computation of gait data. EOS low dose biplanar X-rays have been shown to be a good reference in evaluating various methods of HJC localization in adults. The aim is to evaluate predictive and functional techniques for HJC localization in typically developing (TD) and cerebral palsy (CP) children, using EOS as an image based reference. Eleven TD and 17 CP children underwent 3D gait analysis. Six HJC localization methods were evaluated in each group bilaterally: 3 predictive (Plug in Gait, Bell and Harrington) and 3 functional methods based on the star arc technique (symmetrical center of rotation estimate, center transformation technique and geometrical sphere fitting). All children then underwent EOS low dose biplanar radiographs. Pelvis, lower limbs and their corresponding external markers were reconstructed in 3D. The center of the femoral head was considered as the reference (HJCEOS). Euclidean distances between HJCs estimated by each of the 6 methods and the HJCEOS were calculated; distances were shown to be lower in predictive compared to functional methods (p < 0.0001). Contrarily to findings in adults, functional methods were shown to be less accurate than predictive methods in TD and CP children, which could be mainly due to the shorter thigh segment in children. Harrington method was shown to be the most accurate in the prediction of HJC (mean error ≈ 18 mm, SD = 9 mm) and quasi-equivalent to the Bell method. The bias for each method was quantified, allowing its correction for an improved HJC estimation

Functional assessment using 3D movement analysis can better predict health-related quality of life outcomes in patients with adult spinal deformity: a machine learning approach

IntroductionAdult spinal deformity (ASD) is classically evaluated by health-related quality of life (HRQoL) questionnaires and static radiographic spino-pelvic and global alignment parameters. Recently, 3D movement analysis (3DMA) was used for functional assessment of ASD to objectively quantify patient's independence during daily life activities. The aim of this study was to determine the role of both static and functional assessments in the prediction of HRQoL outcomes using machine learning methods.MethodsASD patients and controls underwent full-body biplanar low-dose x-rays with 3D reconstruction of skeletal segment as well as 3DMA of gait and filled HRQoL questionnaires: SF-36 physical and mental components (PCS&amp;MCS), Oswestry Disability Index (ODI), Beck's Depression Inventory (BDI), and visual analog scale (VAS) for pain. A random forest machine learning (ML) model was used to predict HRQoL outcomes based on three simulations: (1) radiographic, (2) kinematic, (3) both radiographic and kinematic parameters. Accuracy of prediction and RMSE of the model were evaluated using 10-fold cross validation in each simulation and compared between simulations. The model was also used to investigate the possibility of predicting HRQoL outcomes in ASD after treatment.ResultsIn total, 173 primary ASD and 57 controls were enrolled; 30 ASD were followed-up after surgical or medical treatment. The first ML simulation had a median accuracy of 83.4%. The second simulation had a median accuracy of 84.7%. The third simulation had a median accuracy of 87%. Simulations 2 and 3 had comparable accuracies of prediction for all HRQoL outcomes and higher predictions compared to Simulation 1 (i.e., accuracy for PCS = 85 ± 5 vs. 88.4 ± 4 and 89.7% ± 4%, for MCS = 83.7 ± 8.3 vs. 86.3 ± 5.6 and 87.7% ± 6.8% for simulations 1, 2 and 3 resp., p &lt; 0.05). Similar results were reported when the 3 simulations were tested on ASD after treatment.DiscussionThis study showed that kinematic parameters can better predict HRQoL outcomes than stand-alone classical radiographic parameters, not only for physical but also for mental scores. Moreover, 3DMA was shown to be a good predictive of HRQoL outcomes for ASD follow-up after medical or surgical treatment. Thus, the assessment of ASD patients should no longer rely on radiographs alone but on movement analysis as well

Roussouly's sagittal spino-pelvic morphotypes as determinants of gait in asymptomatic adult subjects.

Sagittal alignment is known to greatly vary between asymptomatic adult subjects; however, there are no studies on the possible effect of these differences on gait. The aim of this study is to investigate whether asymptomatic adults with different Roussouly sagittal alignment morphotypes walk differently. Ninety-one asymptomatic young adults (46M & 45W), aged 21.6±2.2years underwent 3D gait analysis and full body biplanar X-rays with three-dimensional (3D) reconstructions of their spines and pelvises and generation of sagittal alignment parameters. Subjects were divided according to Roussouly's sagittal alignment classification. Sagittal alignment and kinematic parameters were compared between Roussouly types. 17 subjects were classified as type 2, 47 as type 3, 26 as type 4 but only 1 as type 1. Type 2 subjects had significantly more mean pelvic retroversion (less mean pelvic tilt) during gait compared to type 3 and 4 subjects (type 2: 8.2°; type 3:11.2°, type 4: 11.3°) and significantly larger ROM pelvic obliquity compared to type 4 subjects (type 2: 11.0°; type 4: 9.1°). Type 2 subjects also had significantly larger maximal hip extension during stance compared to subjects of types 3 and 4 (type 2: -11.9°; type 3: -8.8°; type 4: -7.9°) and a larger ROM of ankle plantar/dorsiflexion compared to type 4 subjects (type 2: 31.1°; type 4: 27.9°). Subjects with type 2 sagittal alignment were shown to have a gait pattern involving both increased hip extension and pelvic retroversion which could predispose to posterior femoroacetabular impingement and consequently osteoarthritis.This study was supported by the research council of the University of Saint-Joseph (grant number: FM189). The study sponsors were involved in neither the study design, collection, analysis and interpretation of data nor in the writing of the manuscript; nor in the decision to submit the manuscript for publication

How the type of sagittal alignment defined by Roussouly determines the gait of asymptomatic adult subject

While curvatures of the sagittal spine are known to greatly differ among asymptomatic adult subjects, there are no studies that determine whether this heterogeneous normality affects gait. This study aimed to elucidate the relationships between normal sagittal spine profiles and gait in asymptomatic adult subjects. Ninety-one asymptomatic adult subjects (age = 21.6 ±2.2, 47 M & 44F) with no prior orthopedic treatment underwent full body biplanar X rays with 3D reconstruction of the spine and pelvis. The following sagittal spino-pelvic parameters were generated from the 3D reconstructions: pelvic incidence, sacral slope, pelvic tilt, L1L5 lordosis, L1-S1 lordosis, T1-T12 kyphosis and T4-T2 kyphosis. Lower limb kinematics was assessed using 3D gait analysis. Each subject was classified into one of the 4 types of normal sagittal alignment previously described by Roussouly. Kruskal-Wallis test was used to evaluate the differences in gait and spino-pelvic parameters between the Roussouly types