Biomechanical gait parameters change with increasing virtual height in a child with spastic cerebral palsy: A case report.

Virtual height exposure coupled with motion capture is feasible to elicit changes in spatiotemporal, kinematic, and kinetic gait parameters in a child with cerebral palsy and should be considered when investigating gait in real-world-scenarios.

Translating scientific recommendations into reality: a feasibility study using group-based high-intensity functional exercise training in adolescents with cerebral palsy.

PURPOSE: To examine the feasibility and effects of a functional high-intensity exercise intervention performed in a group-setting on functionality, cardiovascular health and physical performance in adolescents with cerebral palsy (CP). METHODS: Ten adolescents with a diagnosis of CP (2 females; 16.6 ± 3.4 years; GMFCS: I-II) participated in a 12-week training intervention, containing progressive resistance training using free weights and high-intensity workouts twice a week. The six-minute walking test, arterial stiffness and physical performance (strength and power tests) were measured before and after the intervention. RESULTS: No adverse events were reported. We measured small increases in the six-minute walking test (Δ = 28.8 m, 95% CI [-1.78;52.7]; g = 0.34 [-0.04;0.72]) and a small reduction in arterial stiffness (Δ = -4.65% [-10.90;1.25]; g = -0.46 [-1.36;0.21]). All measures of physical performance increased (0.24 ≤ g ≤ 0.88). CONCLUSION: Functional training with free weights in high-functioning adolescents with CP is safe and effective in increasing parameters of physical performance and cardiovascular health. Positively influenced indicators of everyday independence (i.e. strength parameters) showed a transfer into movements of daily life. Concerns about adverse events through high-intensity training in adolescents with CP appear unjustified when training is performed progressively, following basic training principles.

High-intensity functional exercise in a group-setting is safe in high functioning adolescents with cerebral palsy (CP) when following basic training principles.Compound, multi-joint movements performed at high intensities show a transfer-effect into daily functionality.High-intensity resistance training combined with anaerobic and aerobic exercise should be included in standard therapy for high-functioning adolescents with CP.The group-setting shows potential as innovative strategy for long-term training effectiveness.

Identifying treatment non-responders based on pre-treatment gait characteristics - A machine learning approach.

Background: Paediatric movement disorders such as cerebral palsy often negatively impact walking behaviour. Although clinical gait analysis is usually performed to guide therapy decisions, not all respond positively to their assigned treatment. Identifying these individuals based on their pre-treatment characteristics could guide clinicians towards more appropriate and personalized interventions. Using routinely collected pre-treatment gait and anthropometric features, we aimed to assess whether standard machine learning approaches can be effective in identifying patients at risk of negative treatment outcomes. Methods: Observational data of 119 patients with movement disorders were retrospectively extracted from a local clinical database, comprising sagittal joint angles and spatiotemporal parameters, derived from motion capture data pre- and post-treatment (physiotherapy, orthosis, botulin toxin injections, or surgery). Participants were labelled based on their change in gait profile score (GPS, non-responders with a decline in GPS of <1.6° vs. responders). Their pre-treatment features (sagittal joint angles, spatiotemporal parameters, anthropometrics) were used to train a support vector machine classifier with 5-fold cross-validation and Bayesian optimization within a MATLAB-based Classification Learner App. Results: An average accuracy of 88.2 ± 0.5 % was achieved for identifying participants whose gait will not respond to treatment, with 64 % true negative rate and an area under the curve of 88 %. Conclusion: Overall, a classical machine learning model was able to identify patients at risk of not responding to treatment, based on gait features and anthropometrics collected prior to treatment. The output of such a model could function as a warning signal, notifying clinicians that a certain individual might not respond well to the standard of care and that a more personalized intervention might be needed.

Can developmental trajectories in gait variability provide prognostic clues in motor adaptation among children with mild cerebral palsy? A retrospective observational cohort study.

Aim: To investigate whether multiple domains of gait variability change during motor maturation and if this change over time could differentiate children with a typical development (TDC) from those with cerebral palsy (CwCP). Methods: This cross-sectional retrospective study included 42 TDC and 129 CwCP, of which 99 and 30 exhibited GMFCS level I and II, respectively. Participants underwent barefoot 3D gait analysis. Age and parameters of gait variability (coefficient of variation of stride-time, stride length, single limb support time, walking speed, and cadence; as well as meanSD for hip flexion, knee flexion, and ankle dorsiflexion) were used to fit linear models, where the slope of the models could differ between groups to test the hypotheses. Results: Motor-developmental trajectories of gait variability were able to distinguish between TDC and CwCP for all parameters, except the variability of joint angles. CwCP with GMFCS II also showed significantly higher levels of gait variability compared to those with GMFCS I, these levels were maintained across different ages. Interpretation: This study showed the potential of gait variability to identify and detect the motor characteristics of high functioning CwCP. In future, such trajectories could provide functional biomarkers for identifying children with mild movement related disorders and support the management of expectations.

Consequences of Virtual Reality Experience on Biomechanical Gait Parameters in Children with Cerebral Palsy: A Scoping Review.

Virtual reality (VR), coupled with motion tracking, can investigate walking in a controlled setting while applying various walking challenges. The purpose of this review was to summarize the evidence on consequences of VR on biomechanical gait parameters in children with cerebral palsy. MEDLINE, Embase and Web of Science were searched. Among 7.574 studies, screened by two independent reviewers, seven studies were included, analyzing treadmill (n = 6) or overground walking (n = 1) under VR. Most frequently reported were the spatiotemporal parameters walking speed, stride length, step width, stance phase, and the kinematic parameters range of knee flexion and peak ankle dorsiflexion. However, methodological approaches and reporting of the results were inconsistent among studies. This review reveals that VR can complement information gained from clinical gait analysis. However, this is still an emerging field of research and there is limited knowledge on the effect of VR on gait parameters, notably during overground walking.

Prediction of ground reaction forces and moments during walking in children with cerebral palsy.

Introduction: Gait analysis is increasingly used to support clinical decision-making regarding diagnosis and treatment planning for movement disorders. As a key part of gait analysis, inverse dynamics can be applied to estimate internal loading conditions during movement, which is essential for understanding pathological gait patterns. The inverse dynamics calculation uses external kinetic information, normally collected using force plates. However, collection of external ground reaction forces (GRFs) and moments (GRMs) can be challenging, especially in subjects with movement disorders. In recent years, a musculoskeletal modeling-based approach has been developed to predict external kinetics from kinematic data, but its performance has not yet been evaluated for altered locomotor patterns such as toe-walking. Therefore, the goal of this study was to investigate how well this prediction method performs for gait in children with cerebral palsy. Methods: The method was applied to 25 subjects with various forms of hemiplegic spastic locomotor patterns. Predicted GRFs and GRMs, in addition to associated joint kinetics derived using inverse dynamics, were statistically compared against those based on force plate measurements. Results: The results showed that the performance of the predictive method was similar for the affected and unaffected limbs, with Pearson correlation coefficients between predicted and measured GRFs of 0.71-0.96, similar to those previously reported for healthy adults, despite the motor pathology and the inclusion of toes-walkers within our cohort. However, errors were amplified when calculating the resulting joint moments to an extent that could influence clinical interpretation. Conclusion: To conclude, the musculoskeletal modeling-based approach for estimating external kinetics is promising for pathological gait, offering the possibility of estimating GRFs and GRMs without the need for force plate data. However, further development is needed before implementation within clinical settings becomes possible.

Evolution of muscle coordination and mechanical output following four weeks of arm cranking submaximal training.

Muscle synergies is extensively studied to understand how the neuromusculoskeletal system deals with abundancy. The synergies represent covariant muscles that acts as building blocks for movement production. Nevertheless, little is known on how those synergies evolve following training, learning and expertise. This study reports the influence a 4-weeks submaximal training of arm-cranking on novice participants' muscle synergies. METHODS: 12 participants performed 8 sessions of submaximal training for 4 weeks. One session consisted in two 30-second-maximal power tests followed by six 2-minutes-bouts at 30% of maximal recorded power. Cranking torque and EMG of 11 muscles were recorded during the entire protocol. After EMG normalization, muscle synergies were extracted using NNMF. Similarity was computed using cross-correlation and cosine similarities and statistical evolution across training was tested using repeated measured ANOVA. RESULTS: While maximal power increased across training days nor torque management, EMG or muscle synergies were significantly affected by submaximal training. Nevertheless, results suggest slights modifications of muscle synergies across day despite to non-significant differences. DISCUSSION: Despite the strong complexity of the upper limbs anatomy, our results showed that training didn't induce significant changes in movement realization (mechanical and coordination level). A low-dimensional organization of muscle synergies is selected from the first day and kept through the following training days, despite slight but non-significant modifications.This study supports the hypothesis that motor control for movement production could be simplify using low-dimensional building blocks (muscle synergies). Such building blocks allow stability in movement execution and are slightly adjusted to fit movement requirements with training.

Fetal arthrogryposis-what do we tell the prospective parents?

Arthrogryposis, also termed arthrogryposis multiplex congenita, is a descriptive term for conditions with multiple congenital contractures (MCC). The etiology is extremely heterogeneous. More than 400 specific disorders have been identified so far, which may lead to or are associated with MCC and/or fetal hypo- and akinesia as a clinical sign. With improved sensitivity of prenatal ultrasound and expanding prenatal diagnostic options, clinicians are tasked with providing early detection in order to counsel the prospective parents regarding further prenatal diagnostic as well as management options. We summarize the most important knowledge to raise awareness for early detection in pregnancy. We review essential points for counseling when MCC is detected in order to provide answers to common questions, which, however, cannot replace interdisciplinary expert opinion in the individual case.

High tibial osteotomy effectively redistributes compressive knee loads during walking.

The objectives of this study were to estimate pre- and postoperative lower limb kinematics and kinetics and knee intra-articular forces during gait using musculoskeletal modeling in a cohort of patients with knee osteoarthritis (OA) undergoing high tibial osteotomy (HTO), compare these to controls, and determine correlations between changes in these parameters and Knee Injury and Osteoarthritis Outcome Score (KOOS) subscores after HTO. Sixteen patients with isolated, symptomatic medial compartment knee OA completed pre- and postoperative gait analysis (mean follow-up time: 8.6 months). Sixteen age- and sex-matched asymptomatic volunteers participated as controls. Musculoskeletal modeling was used to evaluate lower limb joint moments and knee contact forces during gait. While HTO had limited influence on sagittal plane kinematics and moments, significant changes in the load distribution at the knee after HTO were observed with a lower postoperative compressive load on the medial compartment during midstance and a higher compressive load on the lateral compartment during early and late stance. Moreover, the lateral shear force in midstance was significantly lower after HTO. Changes in the external knee adduction moment (KAM) did not always coincide with reductions in the knee compressive force in the medial compartment. Biomechanical changes did not correlate with improvements in KOOS subscores. Hence, HTO effectively unloaded the medial compartment by redistributing part of the overall compressive force to the lateral compartment during gait with limited influence on gait function. The KAM may not adequately describe compartmental load magnitude or changes induced by interventions at the compartment level. Clinical trial registration: ClinicalTrials. gov Identifier-NCT02622204. Clinical significance: This study provides important evidence for changes in joint level loads after corrective osteotomy as joint preserving surgery and emphasizes the need for additional biomechanical outcomes of such interventions.

A deep-learning approach for automatically detecting gait-events based on foot-marker kinematics in children with cerebral palsy-Which markers work best for which gait patterns?

Neuromotor pathologies often cause motor deficits and deviations from typical locomotion, reducing the quality of life. Clinical gait analysis is used to effectively classify these motor deficits to gain deeper insights into resulting walking behaviours. To allow the ensemble averaging of spatio-temporal metrics across individuals during walking, gait events, such as initial contact (IC) or toe-off (TO), are extracted through either manual annotation based on video data, or through force thresholds using force plates. This study developed a deep-learning long short-term memory (LSTM) approach to detect IC and TO automatically based on foot-marker kinematics of 363 cerebral palsy subjects (age: 11.8 ± 3.2). These foot-marker kinematics, including 3D positions and velocities of the markers located on the hallux (HLX), calcaneus (HEE), distal second metatarsal (TOE), and proximal fifth metatarsal (PMT5), were extracted retrospectively from standard barefoot gait analysis sessions. Different input combinations of these four foot-markers were evaluated across three gait subgroups (IC with the heel, midfoot, or forefoot). For the overall group, our approach detected 89.7% of ICs within 16ms of the true event with a 18.5% false alarm rate. For TOs, only 71.6% of events were detected with a 33.8% false alarm rate. While the TOE|HEE marker combination performed well across all subgroups for IC detection, optimal performance for TO detection required different input markers per subgroup with performance differences of 5-10%. Thus, deep-learning LSTM based detection of IC events using the TOE|HEE markers offers an automated alternative to avoid operator-dependent and laborious manual annotation, as well as the limited step coverage and inability to measure assisted walking for force plate-based detection of IC events.

Evidence-Based, Implementable Motor Rehabilitation Guidelines for Individuals With Cerebral Palsy.

BACKGROUND: Cerebral palsy is a life-long condition that causes heterogeneous motor disorders. Motor rehabilitation interventions must be adapted to the topography of the symptoms, ambulatory capacity, and age of the individual. Current guidelines do not differentiate between the different profiles of individuals with cerebral palsy, which limits their implementation. OBJECTIVES: To develop evidence-based, implementable guidelines for motor rehabilitation interventions for individuals with cerebral palsy according to the age, topography of the cerebral palsy, and ambulatory capacity of the individual and to determine a level of priority for each intervention. METHODS: We used a mixed methods design that combined a systematic review of the literature on available motor rehabilitation interventions with expert opinions. Based on the French National Authority for Health methodology, recommendations were graded as strong, conditional, or weak. Interventions were then prioritized by the experts according to both the evidence and their own opinions on relevance and implementability to provide a guide for clinicians. All recommendations were approved by experts who were independent from the working group. RESULTS: Strong recommendations as first-line treatments were made for gait training, physical activities, and hand-arm bimanual intensive therapy for all children and adolescents with cerebral palsy. Moderate recommendations were made against passive joint mobilizations, muscle stretching, prolonged stretching with the limb fixed, and neurodevelopmental therapies for all children and adolescents with cerebral palsy. Strong recommendations as first-line treatments were made for gait training for all adults with cerebral palsy and moderate recommendations as moderate importance interventions for strengthening exercises and ankle-foot orthoses for motor impairment of the feet and the ankles. DISCUSSION: These guidelines, which combine research evidence and expert opinions, could help individuals with cerebral palsy and their families to codetermine rehabilitation goals with health professionals, according to their preferences.

Increased Femoral Anteversion Does Not Lead to Increased Joint Forces During Gait in a Cohort of Adolescent Patients.

Orthopedic complications were previously reported for patients with increased femoral anteversion. A more comprehensive analysis of the influence of increased femoral anteversion on joint loading in these patients is required to better understand the pathology and its clinical management. Therefore, the aim was to investigate lower-limb kinematics, joint moments and forces during gait in adolescent patients with increased, isolated femoral anteversion compared to typically developing controls. Secondly, relationships between the joint loads experienced by the patients and different morphological and kinematic features were investigated. Patients with increased femoral anteversion (n = 42, 12.8 ± 1.9 years, femoral anteversion: 39.6 ± 6.9°) were compared to typically developing controls (n = 9, 12.0 ± 3.0 years, femoral anteversion: 18.7 ± 4.1°). Hip and knee joint kinematics and kinetics were calculated using subject-specific musculoskeletal models. Differences between patients and controls in the investigated outcome variables (joint kinematics, moments, and forces) were evaluated through statistical parametric mapping with Hotelling T2 and t-tests (α = 0.05). Canonical correlation analyses (CCAs) and regression analyses were used to evaluate within the patients' cohort the effect of different morphological and kinematic predictors on the outcome variables. Predicted compressive proximo-distal loads in both hip and knee joints were significantly reduced in patients compared to controls. A gait pattern characterized by increased knee flexion during terminal stance (KneeFlex tSt ) was significantly correlated with hip and knee forces, as well as with the resultant force exerted by the quadriceps on the patella. On the other hand, hip internal rotation and in-toeing, did not affect the loads in the joints. Based on the finding of the CCAs and linear regression analyses, patients were further divided into two subgroups based KneeFlex tSt . Patients with excessive KneeFlex tSt presented a significantly higher femoral anteversion than those with normal KneeFlex tSt . Patients with excessive KneeFlex tSt presented significantly larger quadriceps forces on the patella and a larger posteriorly-oriented shear force at the knee, compared to patients with normal KneeFlex tSt , but both patients' subgroups presented only limited differences in terms of joint loading compared to controls. This study showed that an altered femoral morphology does not necessarily lead to an increased risk of joint overloading, but instead patient-specific kinematics should be considered.

Altered Muscle Contributions are Required to Support the Stance Limb During Voluntary Toe-Walking.

Toe-walking characterizes several neuromuscular conditions and is associated with a reduction in gait stability and efficiency, as well as in life quality. The optimal choice of treatment depends on a correct understanding of the underlying pathology and on the individual biomechanics of walking. The objective of this study was to describe gait deviations occurring in a cohort of healthy adult subjects when mimicking a unilateral toe-walking pattern compared to their normal heel-to-toe gait pattern. The focus was to characterize the functional adaptations of the major lower-limb muscles which are required in order to toe walk. Musculoskeletal modeling was used to estimate the required muscle contributions to the joint sagittal moments. The support moment, defined as the sum of the sagittal extensive moments at the ankle, knee, and hip joints, was used to evaluate the overall muscular effort necessary to maintain stance limb stability and prevent the collapse of the knee. Compared to a normal heel-to-toe gait pattern, toe-walking was characterized by significantly different lower-limb kinematics and kinetics. The altered kinetic demands at each joint translated into different necessary moment contributions from most muscles. In particular, an earlier and prolonged ankle plantarflexion contribution was required from the soleus and gastrocnemius during most of the stance phase. The hip extensors had to provide a higher extensive moment during loading response, while a significantly higher knee extension contribution from the vasti was necessary during mid-stance. Compensatory muscular activations are therefore functionally required at every joint level in order to toe walk. A higher support moment during toe-walking indicates an overall higher muscular effort necessary to maintain stance limb stability and prevent the collapse of the knee. Higher muscular demands during gait may lead to fatigue, pain, and reduced quality of life. Toe-walking is indeed associated with significantly larger muscle forces exerted by the quadriceps to the patella and prolonged force transmission through the Achilles tendon during stance phase. Optimal treatment options should therefore account for muscular demands and potential overloads associated with specific compensatory mechanisms.

Subject specific muscle synergies and mechanical output during cycling with arms or legs.

Background: Upper (UL) and lower limb (LL) cycling is extensively used for several applications, especially for rehabilitation for which neuromuscular interactions between UL and LL have been shown. Nevertheless, the knowledge on the muscular coordination modality for UL is poorly investigated and it is still not known whether those mechanisms are similar or different to those of LL. The aim of this study was thus to put in evidence common coordination mechanism between UL and LL during cycling by investigating the mechanical output and the underlying muscle coordination using synergy analysis. Methods: Twenty-five revolutions were analyzed for six non-experts' participants during sub-maximal cycling with UL or LL. Crank torque and muscle activity of eleven muscles UL or LL were recorded. Muscle synergies were extracted using nonnegative matrix factorization (NNMF) and group- and subject-specific analysis were conducted. Results: Four synergies were extracted for both UL and LL. UL muscle coordination was organized around several mechanical functions (pushing, downing, and pulling) with a proportion of propulsive torque almost 80% of the total revolution while LL muscle coordination was organized around a main function (pushing) during the first half of the cycling revolution. LL muscle coordination was robust between participants while UL presented higher interindividual variability. Discussion: We showed that a same principle of muscle coordination exists for UL during cycling but with more complex mechanical implications. This study also brings further results suggesting each individual has unique muscle signature.

Torsional deformities and overuse injuries: what does the literature tell us.

Overuse injuries imply the occurrence of a repetitive or an increased load on a specific anatomical segment which is unable to recover from this redundant microtrauma, thus leading to an inflammatory process of tendons, physis, bursa, or bone. Even if the aetiology is controversial, the most accepted is the traumatic one. Limb malalignment has been cited as one of the major risk factors implicated in the development of overuse injuries. Many authors investigated correlations between anatomical deviations and overuse injuries, but results appear mainly inconclusive. Establishing a causal relationship between mechanical stimuli and symptoms will remain a challenge, but 3D motion analysis, musculoskeletal, and finite element modelling may help in clarifying which are the major risk factors for overuse injuries.

Paralytic dislocation of the hip in children.

Despite the progress made in the past decades, hip disorders are one of the most common orthopedic problems in the context of paralysis. The etiology can be congenital (malformation such as myelomeningoceles, genetic neuromuscular disorders) or acquired (cerebral palsy, post-traumatic). In these conditions, the orthopedic deformities are minimal at birth. They can develop as the child grows, at different ages, depending on the etiology, severity of the neuromuscular disorder and functional potential. Hip subluxation and dislocation can compromise standing and walking capacities, but also the quality of the seated position and the personal care. Daily life activities and participation are restricted and influence the disabled person's quality of life. Paralytic dislocation of the hip is the orthopedic deformity that has be biggest impact on day-to-day life, general health and the overall orthopedic result in adulthood. Neuro-orthopedic care is challenging. However, there are basic principles that one must know to ensure good long-term quality of life in patients suffering from paralytic dislocations of the hip. When planning the treatment strategy, it is essential to take into consideration the day-to-day life and to integrate the patient's experiences and needs, along with those of their caretakers. The objective of this review is to outline the differences in paralytic dislocations of the hip of diverse etiology, to present evaluation principles useful in daily clinical practice and to help practitioners in choosing a treatment strategy.

Impact of the Marker Set Configuration on the Accuracy of Gait Event Detection in Healthy and Pathological Subjects.

For interpreting outcomes of clinical gait analysis, an accurate estimation of gait events, such as initial contact (IC) and toe-off (TO), is essential. Numerous algorithms to automatically identify timing of gait events have been developed based on various marker set configurations as input. However, a systematic overview of the effect of the marker selection on the accuracy of estimating gait event timing is lacking. Therefore, we aim to evaluate (1) if the marker selection influences the accuracy of kinematic algorithms for estimating gait event timings and (2) what the best marker location is to ensure the highest event timing accuracy across various gait patterns. 104 individuals with cerebral palsy (16.0 ± 8.6 years) and 31 typically developing controls (age 20.6 ± 7.8) performed clinical gait analysis, and were divided into two out of eight groups based on the orientation of their foot, in sagittal and frontal plane at mid-stance. 3D marker trajectories of 11 foot/ankle markers were used to estimate the gait event timings (IC, TO) using five commonly used kinematic algorithms. Heatmaps, for IC and TO timing per group were created showing the median detection error, compared to detection using vertical ground reaction forces, for each marker. Our findings indicate that median detection errors can be kept within 7 ms for IC and 13 ms for TO when optimizing the choice of marker and detection algorithm toward foot orientation in midstance. Our results highlight that the use of markers located on the midfoot is robust for detecting gait events across different gait patterns.

Curve location influences spinal balance in coronal and sagittal planes but not transversal trunk motion in adolescents with idiopathic scoliosis: a prospective observational study.

PURPOSE: In adolescent idiopathic scoliosis (AIS), spinal deformity can be seen in the thoracic or in the lumbar area. Although differences according to curve location are well described on standard radiographs, dynamic consequences of such difference remain unclear. Our objective was to explore the differences in dynamic spinal balance according to curve location in AIS patients using gait analysis METHODS: We prospectively included 22 females with AIS planned for surgical correction (16.3 years old, 81% Risser ≥ 4). Patients were divided into two matched cohorts, according to major curve location [right thoracic (Lenke 1) or left lumbar (Lenke 5)]. Gait analysis was performed the day before surgery. Global balance was analyzed as the primary outcome. Local curves parameters (dynamic Cobb angles) were defined as the secondary outcome. RESULTS: In coronal plane, Lenke 5 patients had a left trunk shift, whereas trunk was shifted to the right in Lenke 1 patients (- 20.7 vs 6.3, p = 0.001). In the sagittal plane, the main difference between the two groups was T12 position that remained over the pelvis during gait in Lenke 5 patients, whereas it was anterior to the pelvis in Lenke 1 patients. In the transversal plane, Lenke 5 and Lenke 1 patients presented the same gait abnormalities, with a global trunk rotation to the left (- 4.8 vs - 7.6, p = 0,165). CONCLUSION: This is the first study to provide the results of a direct comparison between Lenke 1 and Lenke 5 patients during gait. Curve location influenced coronal and sagittal balance, but abnormalities of transversal trunk motion were the same, wherever the curve was located. These slides can be retrieved under Electronic Supplementary Material.

Does static trunk motion analysis reflect its true position during daily activities in adolescent with idiopathic scoliosis?

INTRODUCTION: Adolescent idiopathic scoliosis is common condition in pediatric orthopedics that is generally analyzed with standard radiographs. However, the conditions under which the radiographs are made are completely different than the position that patients use during day-to-day activities. We hypothesized that the trunk's static position differs from its dynamic one. The aim of this study was to determine differences between the trunk's static and dynamic positions using motion analysis in adolescents with idiopathic scoliosis. PATIENTS AND METHODS: This prospective, single-center study enrolled adolescents with idiopathic scoliosis who were scheduled to undergo surgical correction. The day before the surgery, radiographs were made and motion analysis was performed (static and dynamic acquisitions). Various parameters were measured on the radiographs and motion analysis, including the coronal vertical axis (CVA), sagittal vertical axis (SVA) and coronal shoulder tilt. RESULTS: The study enrolled 62 patients with a mean age of 15.5 years. There was a significant correlation between the radiographic measurements and the static motion analysis results for most parameters. Conversely, dynamic measurements of CVA, SVA and coronal shoulder tilt were not correlated to their static measurements (R=0.229; 0.198 and -0.109 respectively, all p>0.05). The static coronal shoulder tilt was opposite to the one found during walking (-0.9° vs. 0.5°, p=0.031). DISCUSSION: Our study is the first to compare the trunk's static position with its dynamic position during walking in a cohort of adolescents with idiopathic scoliosis. Motion analysis provides new information about the trunk's dynamic positions. Based on our findings, radiographic analysis only partially captures the spinal alignment and cannot be used to draw reliable conclusions about the trunk's dynamic balance.

Cerebral palsy with dislocated hip and scoliosis: what to deal with first?

PURPOSE: Hip dislocation and scoliosis are common in children with cerebral palsy (CP). Hip dislocation develops in 15% and 20% of children with CP, mainly between three and six years of age and especially in the spastic and dyskinetic subtypes. The risk of scoliosis increases with age and increasing disability as expressed by the Gross Motor Function Score. METHODS: A hip surveillance programme and early surgical treatment have been shown to reduce the hip dislocation, but it remains unclear if a similar programme could reduce the need for neuromuscular scoliosis. When hip dislocation and neuromuscular scoliosis are co-existent, there appears to be no clear guidelines as to which of these deformities should be addressed first: hip or spine. RESULTS: Hip dislocation or windswept deformity may cause pelvic obliquity and initiate scoliosis, while neuromuscular scoliosis itself leads to pelvic obliquity and may increase the risk of hip dislocation especially on the high side. It remains unclear if treating imminent hip dislocation can prevent development of scoliosis and vice versa, but they may present at the same time for surgery. Current expert opinion suggests that when hip dislocation and scoliosis present at the same time, scoliosis associated pelvic obliquity should be corrected before hip reconstruction. If the patient is not presenting with pelvic obliquity the more symptomatic condition should be addressed first. CONCLUSION: Early identification of hip displacement and neuromuscular scoliosis appears to be important for better surgical outcomes.