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Background: The surgical treatment of moderate and severe slipped capital femoral epiphysis is controversial. Treatment ranges from pinning in situ to open dislocation and reduction of the slipped epiphysis. The modified Dunn procedure has been associated with variable avascular necrosis with rates, ranging between 0% and 67%. The aim of this study was to evaluate the outcomes and complications of patients who have undergone a subcapital realignment osteotomy (SCRO) in our center. Methods: A retrospective longitudinal study of the osteotomies performed between 2009 and 2019 in a tertiary referral center for Pediatric Orthopedics in Queensland, Australia. Patient demographics, stability, and severity of slip and surgical outcomes were collected. Results: A total of 123 procedures were performed on 116 patients. The mean age was 12.4 years, 65 (56%) patients were male and the mean posterior sloping angle was 60.10 with 93 (75%) being severe slips. There were 51 (41.5%) Loder's stable and 72 (58%) unstable slipped capital femoral epiphysis. Our overall avascular necrosis rate following SCRO was 17.8%. Time between surgery and diagnosis did not have an effect on avascular necrosis. Conclusion: The subcapital realignment osteotomy remains a controversial and complex procedure for the management of moderate and severe slipped capital femoral epiphysis. We found that our cohort demonstrated an avascular necrosis rate in keeping with the existing literature. This indicates that when performed in a high-volume center with experienced surgical staff, it can be an effective treatment option for these patients. Level of evidence: Level IV.
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PURPOSE: Anterior cruciate ligament (ACL) rupture is increasingly common in paediatric and adolescent populations, typically requiring surgical ACL reconstruction (ACLR) to restore knee stability. However, ACLR substantially alters knee biomechanics (e.g., motion and tissue mechanics) placing the patient at elevated risk of early-onset knee osteoarthritis. METHODS: This study employed a linked neuromusculoskeletal (NMSK)-finite element (FE) model to determine effects of four critical ACLR surgical parameters (graft type, size, location and pre-tension) on tibial articular cartilage stresses in three paediatric knees of different sizes during walking. Optimal surgical combinations were defined by minimal kinematic and tibial cartilage stress deviations in comparison to a corresponding intact healthy knee, with substantial deviations defined by normalized root mean square error (nRMSE) > 10%. RESULTS: Results showed unique trends of principal stress deviations across knee sizes with small knee showing least deviation from intact knee, followed by large- and medium-sized knees. The nRMSE values for cartilage stresses displayed notable variability across different knees. Surgical combination yielding the highest nRMSE in comparison to the one with lowest nRMSE resulted in an increase of maximum principal stress on the medial tibial cartilage by 18.0%, 6.0% and 1.2% for small, medium and large knees, respectively. Similarly, there was an increase of maximum principal stress on lateral tibial cartilage by 11.2%, 4.1% and 12.7% for small, medium and large knees, respectively. Knee phenotype and NMSK factors contributed to deviations in knee kinematics and tibial cartilage stresses. Although optimal surgical configurations were found for each knee size, no generalizable trends emerged emphasizing the subject-specific nature of the knee and neuromuscular system. CONCLUSION: Study findings underscore subject-specific complexities in ACLR biomechanics, necessitating personalized surgical planning for effective restoration of native motion and tissue mechanics. Future research should expand investigations to include a broader spectrum of subject-specific factors to advance personalized surgical planning. LEVEL OF EVIDENCE: Level III.
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Finite element analysis (FEA) is commonly used in orthopaedic research to estimate localised tissue stresses and strains. A variety of boundary conditions have been proposed for isolated femur analysis, but it remains unclear how these assumed constraints influence FEA predictions of bone biomechanics. This study compared the femoral head deflection (FHD), stresses, and strains elicited under four commonly used boundary conditions (fixed knee, mid-shaft constraint, springs, and isostatic methods) and benchmarked these mechanics against the gold standard inertia relief method for normal and pathological femurs (extreme anteversion and retroversion, coxa vara, and coxa valga). Simulations were performed for the stance phase of walking with the applied femoral loading determined from patient-specific neuromusculoskeletal models. Due to unrealistic biomechanics observed for the commonly used boundary conditions, we propose a novel biomechanical constraint method to generate physiological femur biomechanics. The biomechanical method yielded FHD (< 1 mm), strains (approaching 1000 µÎµ), and stresses (< 60 MPa), which were consistent with physiological observations and similar to predictions from the inertia relief method (average coefficient of determination = 0.97, average normalized root mean square error = 0.17). Our results highlight the superior performance of the biomechanical method compared to current methods of constraint for both healthy and pathological femurs.
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Fémur , Análisis de Elementos Finitos , Marcha , Estrés Mecánico , Humanos , Fémur/fisiología , Marcha/fisiología , Fenómenos Biomecánicos , Masculino , Adulto , Simulación por Computador , FemeninoRESUMEN
BACKGROUND AND OBJECTIVE: Incidence of paediatric anterior cruciate ligament (ACL) rupture has increased substantially over recent decades. Following ACL rupture, ACL reconstruction (ACLR) surgery is typically performed to restore passive knee stability. This surgery involves replacing the failed ACL with a graft, however, surgeons must select from range of surgical parameters (e.g., type, size, insertion, and pre-tension) with no robust evidence guiding these decisions. This study presents a systemmatic computational approach to study effects of surgical parameter variation on kinematics of paediatric knees. METHODS: This study used sequentially-linked neuromusculoskeletal (NMSK) finite element (FE) models of three paediatric knees to estimate the: (i) sensitivity of post-operative knee kinematics to four surgical parameters (type, size, insertion, and pre-tension) through multi-input multi-output sensitivity analysis; (ii) influence of motion and loading conditions throughout stance phase of walking gait on sensitivity indices; and (iii) influence of subject-specific anatomy (i.e., knee size) on sensitivivty indices. A previously validated FE model of the intact knee for each subject served as a reference against which ACLR knee kinematics were compared. RESULTS: Sensitivity analyses revealed significant influences of surgical parameters on ACLR knee kinematics, albeit without discernible trend favouring any one parameter. Graft size and pre-tension were primary drivers of variation in knee translations and rotations, however, their effects fluctuated across stance indicating motion and loading conditions affect system sensitivity to surgical parameters. Importantly, the sensitivity of knee kinematics to surgical parameter varied across subjects, indicating geometry (i.e., knee size) influenced system sensitivity. Notably, alterations in graft parameters yielded substantial effects on kinematics (normalized root-mean-square-error > 10 %) compared to intact knee models, indicating surgical parameters vary post-operative knee kinematics. CONCLUSIONS: Overall, this initial study highlights the importance of surgical parameter selection on post-operative kinematics in the paediatric ACLR knee, and provides evidence of the need for personalized surgical planning to ultimately enhance patient outcomes.
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Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Humanos , Niño , Análisis de Elementos Finitos , Fenómenos Biomecánicos , Rango del Movimiento Articular , Articulación de la Rodilla/cirugía , Lesiones del Ligamento Cruzado Anterior/cirugíaRESUMEN
Cerebral palsy (CP) includes a group of neurological conditions caused by damage to the developing brain, resulting in maladaptive alterations of muscle coordination and movement. Estimates of joint moments and contact forces during locomotion are important to establish the trajectory of disease progression and plan appropriate surgical interventions in children with CP. Joint moments and contact forces can be estimated using electromyogram (EMG)-informed neuromusculoskeletal models, but a reduced number of EMG sensors would facilitate translation of these computational methods to clinics. This study developed and evaluated a muscle synergy-informed neuromusculoskeletal modelling approach using EMG recordings from three to four muscles to estimate joint moments and knee contact forces of children with CP and typically developing (TD) children during walking. Using only three to four experimental EMG sensors attached to a single leg and leveraging an EMG database of walking data of TD children, the synergy-informed approach estimated total knee contact forces comparable to those estimated by EMG-assisted approaches that used 13 EMG sensors (children with CP, n = 3, R2 = 0.95 ± 0.01, RMSE = 0.40 ± 0.14 BW; TD controls, n = 3, R2 = 0.93 ± 0.07, RMSE = 0.19 ± 0.05 BW). The proposed synergy-informed neuromusculoskeletal modelling approach could enable rapid evaluation of joint biomechanics in children with unimpaired and impaired motor control within a clinical environment.
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Parálisis Cerebral , Electromiografía , Articulación de la Rodilla , Rodilla , Humanos , Parálisis Cerebral/fisiopatología , Niño , Rodilla/fisiopatología , Rodilla/fisiología , Fenómenos Biomecánicos , Masculino , Articulación de la Rodilla/fisiopatología , Músculo Esquelético/fisiopatología , Músculo Esquelético/fisiología , Femenino , Modelos Biológicos , Caminata/fisiologíaRESUMEN
BACKGROUND: Most cases of toe walking in children are idiopathic. We used pathology-specific neuromusculoskeletal predictive simulations to identify potential underlying neural and muscular mechanisms contributing to idiopathic toe walking. METHODS: A musculotendon contracture was added to the ankle plantarflexors of a generic musculoskeletal model to represent a pathology-specific contracture model, matching the reduced ankle dorsiflexion range-of-motion in a cohort of children with idiopathic toe walking. This model was employed in a forward dynamic simulation controlled by reflexes and supraspinal drive, governed by a multi-objective cost function to predict gait patterns with the contracture model. We validated the predicted gait using experimental gait data from children with idiopathic toe walking with ankle contracture, by calculating the root mean square errors averaged over all biomechanical variables. FINDINGS: A predictive simulation with the pathology-specific model with contracture approached experimental ITW data (root mean square error = 1.37SD). Gastrocnemius activation was doubled from typical gait simulations, but lacked a peak in early stance as present in electromyography. This synthesised idiopathic toe walking was more costly for all cost function criteria than typical gait simulation. Also, it employed a different neural control strategy, with increased length- and velocity-based reflex gains to the plantarflexors in early stance and swing than typical gait simulations. INTERPRETATION: The simulations provide insights into how a musculotendon contracture combined with altered neural control could contribute to idiopathic toe walking. Insights into these neuromuscular mechanisms could guide future computational and experimental studies to gain improved insight into the cause of idiopathic toe walking.
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Contractura , Caminata , Niño , Humanos , Caminata/fisiología , Dedos del Pie/fisiología , Fenómenos Biomecánicos , Marcha/fisiologíaRESUMEN
Physical activity (PA) and physical function (PF) are modifiable risk factors for falls in older adults, but their ability to predict future fall incidence is unclear. The purpose of this study was to determine the predictive ability of baseline measures of PA, PF, and lower limb strength on future falls. A total of 104 participants underwent baseline assessments of PA, PF, and lower limb strength. Falls were monitored prospectively for 12 months. Eighteen participants fell at least once during the 12-month follow-up. Participants recorded almost exclusively sedentary levels of activity. PA, PF, and lower limb strength did not differ between fallers and nonfallers. Twelve participants, who reported a minor musculoskeletal injury in the past 6 months, experienced a fall. The results of this study suggest that in a cohort of highly functioning, sedentary older adults, PA does not distinguish fallers from nonfallers and that the presence of a recent musculoskeletal injury appears to be a possible risk factor for falling.
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Accidentes por Caídas , Ejercicio Físico , Humanos , Anciano , Estudios Prospectivos , Incidencia , Factores de Riesgo , Accidentes por Caídas/prevención & controlRESUMEN
Finite element (FE) models have been widely used to investigate knee joint biomechanics. Most of these models have been developed to study adult knees, neglecting pediatric populations. In this study, an atlas-based approach was employed to develop subject-specific FE models of the knee for eight typically developing pediatric individuals. Initially, validation simulations were performed at four passive tibiofemoral joint (TFJ) flexion angles, and the resulting TFJ and patellofemoral joint (PFJ) kinematics were compared to corresponding patient-matched measurements derived from magnetic resonance imaging (MRI). A neuromusculoskeletal-(NMSK)-FE pipeline was then used to simulate knee biomechanics during stance phase of walking gait for each participant to evaluate model simulation of a common motor task. Validation simulations demonstrated minimal error and strong correlations between FE-predicted and MRI-measured TFJ and PFJ kinematics (ensemble average of root mean square errors < 5 mm for translations and < 4.1° for rotations). The FE-predicted kinematics were strongly correlated with published reports (ensemble average of Pearson's correlation coefficients (ρ) > 0.9 for translations and ρ > 0.8 for rotations), except for TFJ mediolateral translation and abduction/adduction rotation. For walking gait, NMSK-FE model-predicted knee kinematics, contact areas, and contact pressures were consistent with experimental reports from literature. The strong agreement between model predictions and experimental reports underscores the capability of sequentially linked NMSK-FE models to accurately predict pediatric knee kinematics, as well as complex contact pressure distributions across the TFJ articulations. These models hold promise as effective tools for parametric analyses, population-based clinical studies, and enhancing our understanding of various pediatric knee injury mechanisms. They also support intervention design and prediction of surgical outcomes in pediatric populations.
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Articulación de la Rodilla , Articulación Patelofemoral , Adulto , Humanos , Niño , Análisis de Elementos Finitos , Articulación de la Rodilla/patología , Rodilla/diagnóstico por imagen , Imagen por Resonancia Magnética , Fenómenos Biomecánicos , Rango del Movimiento ArticularRESUMEN
Purpose: Retinopathy of prematurity (ROP) is a sight-threatening vasoproliferative retinal disease affecting premature infants. The detection of plus disease, a severe form of ROP requiring treatment, remains challenging owing to subjectivity, frequency, and time intensity of retinal examinations. Recent artificial intelligence (AI) algorithms developed to detect plus disease aims to alleviate these challenges; however, they have not been tested against a diverse neonatal population. Our study aims to validate ROP.AI, an AI algorithm developed from a single cohort, against a multicenter Australian cohort to determine its performance in detecting plus disease. Methods: Retinal images captured during routine ROP screening from May 2021 to February 2022 across five major tertiary centers throughout Australia were collected and uploaded to ROP.AI. AI diagnostic output was compared with one of five ROP experts. Sensitivity, specificity, negative predictive value, and area under the receiver operator curve were determined. Results: We collected 8052 images. The area under the receiver operator curve for the diagnosis of plus disease was 0.75. ROP.AI achieved 84% sensitivity, 43% specificity, and 96% negative predictive value for the detection of plus disease after operating point optimization. Conclusions: ROP.AI was able to detect plus disease in an external, multicenter cohort despite being trained from a single center. Algorithm performance was demonstrated without preprocessing or augmentation, simulating real-world clinical applicability. Further training may improve generalizability for clinical implementation. Translational Relevance: These results demonstrate ROP.AI's potential as a screening tool for the detection of plus disease in future clinical practice and provides a solution to overcome current diagnostic challenges.
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Aprendizaje Profundo , Retinopatía de la Prematuridad , Recién Nacido , Lactante , Humanos , Inteligencia Artificial , Retinopatía de la Prematuridad/diagnóstico , Edad Gestacional , Australia/epidemiología , AlgoritmosRESUMEN
Spasticity is a common impairment within pediatric neuromusculoskeletal disorders. How spasticity contributes to gait deviations is important for treatment selection. Our aim was to evaluate the pathophysiological mechanisms underlying gait deviations seen in children with spasticity, using predictive simulations. A cluster analysis was performed to extract distinct gait patterns from experimental gait data of 17 children with spasticity to be used as comparative validation data. A forward dynamic simulation framework was employed to predict gait with either velocity- or force-based hyperreflexia. This framework entailed a generic musculoskeletal model controlled by reflexes and supraspinal drive, governed by a multiobjective cost function. Hyperreflexia values were optimized to enable the simulated gait to best match experimental gait patterns. Three experimental gait patterns were extracted: (1) increased knee flexion, (2) increased ankle plantar flexion, and (3) increased knee flexion and ankle plantar flexion when compared with typical gait. Overall, velocity-based hyperreflexia outperformed force-based hyperreflexia. The first gait pattern could mostly be explained by rectus femoris and hamstrings velocity-based hyperreflexia, the second by gastrocnemius velocity-based hyperreflexia, and the third by gastrocnemius, soleus, and hamstrings velocity-based hyperreflexia. This study shows how velocity-based hyperreflexia from specific muscles contributes to different spastic gait patterns, which may help in providing targeted treatment.
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Background: Growth disturbance to leg length or coronal plane alignment are important considerations in pediatric anterior cruciate ligament (ACL) reconstruction (ACLR). Purpose/Hypothesis: The purpose of this study was to investigate the lower limb alignment and leg length of pediatric patients preoperatively and at approximately 1 year after transphyseal ACLR. Our hypothesis was that there would be no significant change in leg-length discrepancy (LLD) or operated-side alignment at follow-up. Study Design: Case series; Level of evidence, 4. Methods: Data were extracted from the prospective Queensland Children's Hospital Pediatric ACL Injury Registry. Long-leg alignment radiographs were captured preoperatively and at an approximately 12-month postoperative follow-up. Radiographic measures included leg length, LLD (injured minus uninjured leg length), mechanical axis deviation (MAD), mechanical and anatomical lateral distal femoral angle (mLDFA and aLDFA, respectively), and medial proximal tibial angle. We evaluated the effect of time (annual vs baseline) on imaging measurements with analysis of covariance, using the covariates of age, sex, and body mass index. Results: Data were available for 104 patients, of whom 34 (33%) had >12 months of skeletal growth remaining based on skeletal age. At an average follow-up time of 14.5 months after ACLR, there were no significant differences in mean lower limb alignment or longitudinal growth compared with baseline. However, seven patients demonstrated clinically significant changes to their mechanical axis or LLD (>10 mm change). A subgroup analysis of patients with >12 months of growth remaining (n = 34) demonstrated no statistically significant changes in mean alignment or LLD. Before surgery, LLD was -1.39 mm and the injured limb was in significantly more valgus compared with the uninjured lower limb (mean difference: MAD, 4.79 mm [95% CI, 2.64 to 6.94 mm]; mLDFA, -0.93° [95% CI, -1.29° to -0.57°], and aLDFA, -0.91° [95% CI, -1.31° to -0.50°]). Conclusion: After ACLR, there were no statistically significant changes in mean alignment or longitudinal growth; however, 7 out of 104 patients (6.7%) demonstrated clinically significant changes in alignment or LLD. Preoperatively, the injured limb was statistically significantly in more valgus compared with the uninjured limb with lateralized MAD.
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Neuromusculoskeletal models are a powerful tool to investigate the internal biomechanics of an individual. However, commonly used neuromusculoskeletal models are generated via linear scaling of generic templates derived from elderly adult anatomies and poorly represent a child, let alone children with a neuromuscular disorder whose musculoskeletal structures and muscle activation patterns are profoundly altered. Model personalization can capture abnormalities and appropriately describe the underlying (altered) biomechanics of an individual. In this work, we explored the effect of six different levels of neuromusculoskeletal model personalization on estimates of muscle forces and knee joint contact forces to tease out the importance of model personalization for normal and abnormal musculoskeletal structures and muscle activation patterns. For six children, with and without cerebral palsy, generic scaled models were developed and progressively personalized by (1) tuning and calibrating musculotendon units' parameters, (2) implementing an electromyogram-assisted approach to synthesize muscle activations, and (3) replacing generic anatomies with image-based bony geometries, and physiologically and physically plausible muscle kinematics. Biomechanical simulations of gait were performed in the OpenSim and CEINMS software on ten overground walking trials per participant. A mixed-ANOVA test, with Bonferroni corrections, was conducted to compare all models' estimates. The model with the highest level of personalization produced the most physiologically plausible estimates. Model personalization is crucial to produce physiologically plausible estimates of internal biomechanical quantities. In particular, personalization of musculoskeletal anatomy and muscle activation patterns had the largest effect overall. Increased research efforts are needed to ease the creation of personalized neuromusculoskeletal models.
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Articulación de la Rodilla , Músculo Esquelético , Niño , Adulto , Humanos , Anciano , Músculo Esquelético/fisiología , Electromiografía , Articulación de la Rodilla/fisiología , Marcha/fisiología , Caminata/fisiología , Fenómenos Biomecánicos , Modelos BiológicosRESUMEN
PURPOSE: Artificial intelligence (AI) offers considerable promise for retinopathy of prematurity (ROP) screening and diagnosis. The development of deep-learning algorithms to detect the presence of disease may contribute to sufficient screening, early detection, and timely treatment for this preventable blinding disease. This review aimed to systematically examine the literature in AI algorithms in detecting ROP. Specifically, we focused on the performance of deep-learning algorithms through sensitivity, specificity, and area under the receiver operating curve (AUROC) for both the detection and grade of ROP. METHODS: We searched Medline OVID, PubMed, Web of Science, and Embase for studies published from January 1, 2012, to September 20, 2021. Studies evaluating the diagnostic performance of deep-learning models based on retinal fundus images with expert ophthalmologists' judgment as reference standard were included. Studies which did not investigate the presence or absence of disease were excluded. Risk of bias was assessed using the QUADAS-2 tool. RESULTS: Twelve studies out of the 175 studies identified were included. Five studies measured the performance of detecting the presence of ROP and seven studies determined the presence of plus disease. The average AUROC out of 11 studies was 0.98. The average sensitivity and specificity for detecting ROP was 95.72% and 98.15%, respectively, and for detecting plus disease was 91.13% and 95.92%, respectively. CONCLUSION: The diagnostic performance of deep-learning algorithms in published studies was high. Few studies presented externally validated results or compared performance to expert human graders. Large scale prospective validation alongside robust study design could improve future studies.
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PURPOSE: This study investigated whether the functional improvements associated with functional electrical stimulation-assisted cycling, goal-directed training, and adapted cycling in children with cerebral palsy were maintained 8 weeks after the intervention ceased. METHODS: The intervention (2 × 1-hour supervised sessions and 1-hour home program/week) ran for 8 weeks. Primary outcomes were the Gross Motor Function Measure (GMFM-88) and the Canadian Occupational Performance Measure (COPM). Secondary outcomes included the GMFM-66 and goal scores, 5 times sit-to-stand test (FTSTS), Participation and Environment Measure-Children and Youth (PEM-CY), Pediatric Evaluation of Disability Inventory Computer Adaptive Test (PEDI-CAT), and cycling power output (PO). Outcomes were assessed at baseline, 8 and 16 weeks. RESULTS: Twenty children participated (mean age = 10 years 3 months; SD = 2 years 11 months; Gross Motor Function Classification System II = 5, III = 6, and IV = 9). Improvements were retained above baseline at 16 weeks on the GMFM and COPM. Improvements in cycling PO, PEDI-CAT scores, PEM-CY environmental barriers and FTSTS were also retained. CONCLUSION: Functional improvements in children with cerebral palsy were retained 8 weeks post-intervention.
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Parálisis Cerebral , Canadá , Parálisis Cerebral/rehabilitación , Objetivos , Humanos , Destreza Motora , Modalidades de FisioterapiaRESUMEN
INTRODUCTION: There is currently no clear indication in the literature regarding a single or double hamstring tendon (single bundle) autograft for anterior cruciate ligament (ACL) reconstruction in the paediatric patient. The primary aim of this single blind randomised controlled trial is to determine whether a single or double hamstring tendon graft ACLR leads to superior clinical outcomes postsurgery in paediatric patients with ACL injury. METHODS AND ANALYSIS: Single site, prospective, single blind, randomised controlled trial with two parallel treatment arms. 100 patients aged 10-18 years who present with an isolated ACL tear±meniscal injury, verified on MRI, will be randomly allocated to one of the two surgical groups. The primary outcomes will be side-to-side difference in anterior tibial translation and graft failure incidence 12 months postsurgery. Primary and secondary outcomes will also be assessed at 2-year and 5-year postsurgery. ETHICS AND DISSEMINATION: Results will be presented in peer-reviewed journals and at international conferences and disseminated to participants and healthcare professionals via newsletters and hospital presentations. This study is approved by the Children's Health Queensland Hospital and Health Service Human Research Ethics committee. TRIAL REGISTRATION NUMBER: ACTRN12620001170910p; Australian New Zealand Clinical Trials Registry.
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Lesiones del Ligamento Cruzado Anterior , Reconstrucción del Ligamento Cruzado Anterior , Tendones Isquiotibiales , Traumatismos de la Rodilla , Lesiones del Ligamento Cruzado Anterior/cirugía , Reconstrucción del Ligamento Cruzado Anterior/efectos adversos , Australia , Niño , Tendones Isquiotibiales/trasplante , Humanos , Traumatismos de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Método Simple CiegoRESUMEN
BACKGROUND AND OBJECTIVE: Accurate representation of bone shape is important for subject-specific musculoskeletal models as it may influence modelling of joint kinematics, kinetics, and muscle dynamics. Statistical shape modelling is a method to estimate bone shape from minimal information, such as anatomical landmarks, and to avoid the time and cost associated with reconstructing bone shapes from comprehensive medical imaging. Statistical shape models (SSM) of lower limb bones have been developed and validated for adult populations but are not applicable to paediatric populations. This study aimed to develop SSM for paediatric lower limb bones and evaluate their reconstruction accuracy using sparse anatomical landmarks. METHODS: We created three-dimensional models of 56 femurs, 29 pelves, 56 tibias, 56 fibulas, and 56 patellae through segmentation of magnetic resonance images taken from 29 typically developing children (15 females; 13 ± 3.5 years). The SSM for femur, pelvis, tibia, fibula, patella, haunch (i.e., combined femur and pelvis), and shank (i.e., combined tibia and fibula) were generated from manual segmentation of comprehensive magnetic resonance images to describe the shape variance of the cohort. We implemented a leave-one-out cross-validation method wherein SSM were used to reconstruct novel bones (i.e., those not included in SSM generation) using full- (i.e., full segmentation) and sparse- (i.e., anatomical landmarks) input, and then compared these reconstructions against bones segmented from magnetic resonance imaging. Reconstruction performance was evaluated using root mean squared errors (RMSE, mm), Jaccard index (0-1), Dice similarity coefficient (DSC) (0-1), and Hausdorff distance (mm). All results reported in this abstract are mean ± standard deviation. RESULTS: Femurs, pelves, tibias, fibulas, and patellae reconstructed via SSM using full-input had RMSE between 0.89 ± 0.10 mm (patella) and 1.98 ± 0.38 mm (pelvis), Jaccard indices between 0.77 ± 0.03 (pelvis) and 0.90 ± 0.02 (tibia), DSC between 0.87 ± 0.02 (pelvis) and 0.95 ± 0.01 (tibia), and Hausdorff distances between 2.45 ± 0.57 mm (patella) and 9.01 ± 2.36 mm (pelvis). Reconstruction using sparse-input had RMSE ranging from 1.33 ± 0.61 mm (patella) to 3.60 ± 1.05 mm (pelvis), Jaccard indices ranging from 0.59 ± 0.10 (pelvis) to 0.83 ± 0.03 (tibia), DSC ranging from 0.74 ± 0.08 (pelvis) to 0.90 ± 0.02 (tibia), and Hausdorff distances ranging from 3.21 ± 1.19 mm (patella) to 12.85 ± 3.24 mm (pelvis). CONCLUSIONS: The SSM of paediatric lower limb bones showed reconstruction accuracy consistent with previously developed SSM and outperformed adult-based SSM when used to reconstruct paediatric bones.
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Fémur , Modelos Estadísticos , Adulto , Niño , Femenino , Fémur/diagnóstico por imagen , Humanos , Imagenología Tridimensional/métodos , Extremidad Inferior/diagnóstico por imagen , Pelvis , Tibia/diagnóstico por imagenRESUMEN
OBJECTIVES: To assess the cost-effectiveness of care coordination, compared with standard care, for children with chronic noncomplex medical conditions. METHODS: A total of 81 children aged between 2 and 15 years newly diagnosed with a noncomplex chronic condition were randomized to either care coordination or standard care as part of a multicenter randomized controlled trial. Families receiving care coordination were provided access to an Allied Health Liaison Officer, who facilitated family-centered healthcare access across hospital, education, primary care, and community sectors. Costs were estimated over a 12-month period from the perspective of the Australian health system. Health outcomes were valued as quality-adjusted life-years (QALYs). Caregiver productivity costs were included in an alternative base-case analysis, and key assumptions were tested in a series of one-way sensitivity analyses. A probabilistic sensitivity analysis was conducted to investigate the overall impact of uncertainty in the data. RESULTS: Children in the intervention arm incurred an average of $17 in additional health system costs (95% confidence interval -3861 to 1558) and gained an additional 0.031 QALYs (95% confidence interval -0.29 to 0.092) over 12 months, producing an incremental cost-effectiveness ratio of $548 per QALY. When uncertainty was considered, there was a 73% likelihood that care coordination was cost-effective from a health system perspective, assuming a willingness to pay of $50 000 per QALY. This increased to 78% when caregiver productivity costs were included. CONCLUSIONS: Care coordination is likely to be a cost-effective intervention for children with chronic noncomplex medical conditions in the Australian healthcare setting.
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BACKGROUND: The tibialis anterior tendon transfer (TATT) is the suggested surgical intervention in the Ponseti method for treatment of dynamic recurrent congenital talipes equinovarus (clubfoot) presenting as hindfoot varus and forefoot supination during the swing phase of gait. The indication for surgery, however, is typically based on visual assessment, which does not sufficiently examine the variability of foot motion in this cohort. RESEARCH QUESTION: The aim of this research was to determine whether subgroups, based on foot model kinematics, existed within a clubfoot cohort being considered for TATT surgery. METHODS: Sixteen children with recurrent clubfoot that had been previously treated with the Ponseti method and were being considered for tendon transfer surgery were prospectively recruited for this study and were required to attend a pre-surgery data collection session at the Queensland Children's Motion Analysis Service (QCMAS). Data collected included standard Plug-in-Gait (PiG) kinematics and kinetics, Oxford Foot Model (OFM) foot kinematics, and regional plantar loads based on anatomical masking using the integrated kinematic-pressure method. RESULTS: Results of this study identified two clear subgroups within the cohort. One group presented with increased hindfoot inversion across 91 % of the gait cycle. The second group presented with increased hindfoot adduction across 100 % of the gait cycle. Hindfoot adduction was statistically significantly different between the two groups. SIGNIFICANCE: The identification of these two groups propose a need for further classification of deformity within this cohort and query the appropriateness of this surgical intervention for both presentations.
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Pie Equinovaro , Fenómenos Biomecánicos , Pie Equinovaro/diagnóstico , Pie Equinovaro/cirugía , Pie , Humanos , Transferencia Tendinosa/métodos , Resultado del TratamientoRESUMEN
BACKGROUND: There is significant variability in clinical pathways available in the diagnostic assessment of ASD, including the order and timing of allied health assessments in relation to paediatrician consultations. Allied health professionals in first-contact models are increasingly used to improve the timeliness of healthcare access, whilst complementing medical specialty workforce shortages. Anecdotally, the implementation of allied health first-contact models in paediatrics has improved waitlists and timely access to healthcare. However, no rigorous studies have been conducted to evaluate the outcomes of these models. This study aims to determine the impacts of an allied health first-contact model on health service use and costs and patient quality of life and satisfaction. METHODS: An open, semi-blinded, multi-centre randomised controlled trial in paediatric outpatient clinics at two Australian metropolitan public hospitals. 56 children (0-16 years) fulfilling the inclusion criteria will be randomised to one of two clinical pathways for assessment of ASD: (1) allied health first-contact or (2) medical first-contact model. Cost outcomes will be collected from both health service and family perspectives. Caregiver-reported outcome measures include: Pediatric Quality of Life Inventory (PedsQL), the EuroQOL Five Dimension Youth Version (EQ-5D-Y), the Autism Family Experience Questionnaire (AFEQ) and Measure of Processes of Care. DISCUSSION: Evidence of improvements in service and consumer centric outcomes will help inform the development and implementation of high-value, evidenced based models of care for the assessment of ASD in children. The findings from this study are expected to contribute to the evidence base around the costs and consequences of allied health first contact models for the assessment of children with ASD in the Australian setting. Findings of this study may help to inform the allocation of health care resources while maintaining, or potentially improving, patient and family quality of life and experience of care. These findings may be useful in informing the wider adoption of these models in Australia and internationally, particularly in healthcare settings where medical specialist shortages exist. TRIAL REGISTRATION: Australia and New Zealand Clinical Trials Register (ANZCTR) ACTRN12621001433897 . Registered: 25th October, 2021.