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Kainz H, Koller W, Wallnöfer E, Bader TR, Mindler GT, Kranzl A. A framework based on subject-specific musculoskeletal models and Monte Carlo simulations to personalize muscle coordination retraining. Sci Rep 2024; 14:3567. [PMID: 38347085 PMCID: PMC10861532 DOI: 10.1038/s41598-024-53857-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2023] [Accepted: 02/06/2024] [Indexed: 02/15/2024] Open
Abstract
Excessive loads at lower limb joints can lead to pain and degenerative diseases. Altering joint loads with muscle coordination retraining might help to treat or prevent clinical symptoms in a non-invasive way. Knowing how much muscle coordination retraining can reduce joint loads and which muscles have the biggest impact on joint loads is crucial for personalized gait retraining. We introduced a simulation framework to quantify the potential of muscle coordination retraining to reduce joint loads for an individuum. Furthermore, the proposed framework enables to pinpoint muscles, which alterations have the highest likelihood to reduce joint loads. Simulations were performed based on three-dimensional motion capture data of five healthy adolescents (femoral torsion 10°-29°, tibial torsion 19°-38°) and five patients with idiopathic torsional deformities at the femur and/or tibia (femoral torsion 18°-52°, tibial torsion 3°-50°). For each participant, a musculoskeletal model was modified to match the femoral and tibial geometry obtained from magnetic resonance images. Each participant's model and the corresponding motion capture data were used as input for a Monte Carlo analysis to investigate how different muscle coordination strategies influence joint loads. OpenSim was used to run 10,000 simulations for each participant. Root-mean-square of muscle forces and peak joint contact forces were compared between simulations. Depending on the participant, altering muscle coordination led to a maximum reduction in hip, knee, patellofemoral and ankle joint loads between 5 and 18%, 4% and 45%, 16% and 36%, and 2% and 6%, respectively. In some but not all participants reducing joint loads at one joint increased joint loads at other joints. The required alteration in muscle forces to achieve a reduction in joint loads showed a large variability between participants. The potential of muscle coordination retraining to reduce joint loads depends on the person's musculoskeletal geometry and gait pattern and therefore showed a large variability between participants, which highlights the usefulness and importance of the proposed framework to personalize gait retraining.
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Affiliation(s)
- Hans Kainz
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Auf der Schmelz 6a (USZ II), 1150, Vienna, Austria.
- Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.
| | - Willi Koller
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Auf der Schmelz 6a (USZ II), 1150, Vienna, Austria
- Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
- Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Elias Wallnöfer
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Auf der Schmelz 6a (USZ II), 1150, Vienna, Austria
- Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
- Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Till R Bader
- Department of Radiology, Orthopaedic Hospital Speising, Vienna, Austria
| | - Gabriel T Mindler
- Department of Paediatric Orthopaedics and Foot Surgery, Orthopaedic Hospital Speising, Vienna, Austria
- Vienna Bone and Growth Center, Vienna, Austria
| | - Andreas Kranzl
- Vienna Bone and Growth Center, Vienna, Austria
- Laboratory for Gait and Movement Analysis, Orthopaedic Hospital Speising, Vienna, Austria
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Foley SA, Washabaugh EP. Applying elastic resistance bands for gait training: A simulation-based study to determine how band configuration affects gait biomechanics and muscle activation. Gait Posture 2024; 108:320-328. [PMID: 38199091 DOI: 10.1016/j.gaitpost.2023.12.022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/29/2023] [Revised: 12/20/2023] [Accepted: 12/30/2023] [Indexed: 01/12/2024]
Abstract
BACKGROUND Wearable robotic exoskeletons and leg braces are desirable for gait rehabilitation because they can apply loads directly to an affected joint. Yet, they are not widely used in clinics because they are costly and complex to set up. Conversely, tethered devices, such as elastic resistance bands, are widely available in clinics, are low-cost, and are quick to set up. However, resistance bands will affect walking differently based on how they are configured to pull on the leg (e.g., pulling forward or backward). RESEARCH QUESTION How can a resistance band be configured to alter muscle activation and gait biomechanics based on the segment it is attached to and the angle with which it attaches? METHODS We used an open-source musculoskeletal modeling platform to emulate several configurations of an elastic band pulling on the ankle, calf, and thigh at various angles during non-pathological walking. We evaluated gait biomechanics and simulated muscle activation using computed muscle control (CMC) and identified a subset of four configurations with potential applications for gait training. Eight non-pathological participants then walked on a treadmill under these configurations to verify how these configurations altered muscle activation. RESULTS We found that muscle activity greatly varied based on the location where the elastic band is attached and the angle with which the elastic band pulls on the leg. Notably, specific angles can be used to pull on the legs to elicit an increase or decrease in muscle activation. SIGNIFICANCE This study provides insight into how tethered devices can be configured to provide assistance or resistance during gait training. This information can be applied when developing low-cost gait training solutions for addressing individuals' impairments.
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Affiliation(s)
- Sierra A Foley
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA
| | - Edward P Washabaugh
- Department of Biomedical Engineering, Wayne State University, Detroit, MI, USA.
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Ravera EP, Rozumalski A. Selective dorsal rhizotomy and its effect on muscle force during walking: A comprehensive study. J Biomech 2024; 164:111968. [PMID: 38325195 DOI: 10.1016/j.jbiomech.2024.111968] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2023] [Revised: 01/03/2024] [Accepted: 01/28/2024] [Indexed: 02/09/2024]
Abstract
Selective dorsal rhizotomy (SDR) is commonly used to permanently reduce spasticity in children with cerebral palsy (CP). However, studies have yielded varying results regarding muscle strength and activity after SDR. Some studies indicate weakness or no changes, while a recent study using NMSK simulations demonstrates improvements in muscle forces during walking. These findings suggest that SDR may alleviate spasticity, reducing dynamic muscle constraints and enhancing muscle force without altering muscle activity during walking in children with CP. In this study, we combined NMSK simulations with physical examinations to assess children with CP who underwent SDR, comparing them to well-matched peers who did not undergo the procedure. Each group (SDR and No-SDR) included 81 children, with pre- and post-SDR assessments. Both groups were well-matched in terms of demographics, clinical characteristics, and gait parameters. The results of the physical examination indicate that SDR significantly reduces spasticity without impacting muscle strength. Furthermore, our findings show no significant differences in gait deviation index improvements and walking speed between the two groups. Additionally, there were no statistically significant changes in muscle activity during walking before and after SDR for both groups. NMSK results demonstrate a significant increase in muscle force in the semimembranosus and calf muscles during walking, compared to children with CP who received other clinical treatments. Our findings confirm that although SDR does not significantly impact muscle strength compared to other treatments, it creates a more favorable dynamic environment for suboptimal muscle force production, which is essential for walking.
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Affiliation(s)
- Emiliano Pablo Ravera
- Group of Analysis, Modeling, Processing and Clinician Implementation of Biomechanical Signals and Systems, Bioengineering and Bioinformatics Institute, CONICET-UNER, Oro Verde, Argentina; Human Movement Research Laboratory, School of Engineering, National University of Entre Ríos (UNER), Oro Verde, Argentina.
| | - Adam Rozumalski
- The James R. Gage Center for Gait & Motion Analysis, Gillette Children's Specialty Healthcare, St. Paul, MN, United States of America.
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Persad LS, Binder-Markey BI, Shin AY, Lieber RL, Kaufman KR. American Society of Biomechanics Journal of Biomechanics Award 2022: Computer models do not accurately predict human muscle passive muscle force and fiber length: Evaluating subject-specific modeling impact on musculoskeletal model predictions. J Biomech 2023; 159:111798. [PMID: 37713970 DOI: 10.1016/j.jbiomech.2023.111798] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2023] [Revised: 09/06/2023] [Accepted: 09/07/2023] [Indexed: 09/17/2023]
Abstract
Musculoskeletal models are valuable for studying and understanding the human body in a variety of clinical applications that include surgical planning, injury prevention, and prosthetic design. Subject-specific models have proven to be more accurate and useful compared to generic models. Nevertheless, it is important to validate all models when possible. To this end, gracilis muscle-tendon parameters were directly measured intraoperatively and used to test model predictions. The aim of this study was to evaluate the benefits and limitations of systematically incorporating subject-specific variables into muscle models used to predict passive force and fiber length. The results showed that incorporating subject-specific values generally reduced errors, although significant errors still existed. Optimization of the modeling parameter "tendon slack length" was explored in two cases: minimizing fiber length error and minimizing passive force error. The results showed that using all subject-specific values yielded the most favorable outcome in both models and optimization cases. However, the trade-off between fiber length error and passive force error will depend on the specific circumstances and research objectives due to significant individual errors. Notably, individual fiber length and passive force errors were as high as 20% and 37% respectively. Finally, the modeling parameter "tendon slack length" did not correlate with any real-world anatomical length.
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Affiliation(s)
- Lomas S Persad
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | | | - Alexander Y Shin
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA
| | - Richard L Lieber
- Shirley Ryan AbilityLab, Chicago, IL, USA; Northwestern University, Chicago. IL, USA; Hines VA Medical Center, Maywood, IL, USA
| | - Kenton R Kaufman
- Department of Orthopedic Surgery, Mayo Clinic, Rochester, MN, USA.
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Koller W, Baca A, Kainz H. The gait pattern and not the femoral morphology is the main contributor to asymmetric hip joint loading. PLoS One 2023; 18:e0291789. [PMID: 37751435 PMCID: PMC10522038 DOI: 10.1371/journal.pone.0291789] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Accepted: 09/06/2023] [Indexed: 09/28/2023] Open
Abstract
Gait asymmetry and skeletal deformities are common in many children with cerebral palsy (CP). Changes of the hip joint loading, i.e. hip joint contact force (HJCF), can lead to pathological femoral growth. A child's gait pattern and femoral morphology affect HJCFs. The twofold aim of this study was to (1) evaluate if the asymmetry in HJCFs is higher in children with CP compared to typically developing (TD) children and (2) identify if the bony morphology or the subject-specific gait pattern is the main contributor to asymmetric HJCFs. Magnetic resonance images (MRI) and three-dimensional gait analysis data of twelve children with CP and fifteen TD children were used to create subject-specific musculoskeletal models and calculate HJCF using OpenSim. Root-mean-square-differences between left and right HJCF magnitude and orientation were computed and compared between participant groups (CP versus TD). Additionally, the influence on HJCF asymmetries solely due to the femoral morphology and solely due to the gait pattern was quantified. Our findings demonstrate that the gait pattern is the main contributor to asymmetric HJCFs in CP and TD children. Children with CP have higher HJCF asymmetries which is probably the result of larger asymmetries in their gait pattern compared to TD children. The gained insights from our study highlight that clinical interventions should focus on normalizing the gait pattern and therefore the hip joint loading to avoid the development of femoral deformities.
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Affiliation(s)
- Willi Koller
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
- Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
- Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Arnold Baca
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Hans Kainz
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
- Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
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Chen Z, Franklin DW. Musculotendon Parameters in Lower Limb Models: Simplifications, Uncertainties, and Muscle Force Estimation Sensitivity. Ann Biomed Eng 2023; 51:1147-1164. [PMID: 36913088 PMCID: PMC10172227 DOI: 10.1007/s10439-023-03166-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2022] [Accepted: 02/08/2023] [Indexed: 03/14/2023]
Abstract
Musculotendon parameters are key factors in the Hill-type muscle contraction dynamics, determining the muscle force estimation accuracy of a musculoskeletal model. Their values are mostly derived from muscle architecture datasets, whose emergence has been a major impetus for model development. However, it is often not clear if such parameter update indeed improves simulation accuracy. Our goal is to explain to model users how these parameters are derived and how accurate they are, as well as to what extent errors in parameter values might influence force estimation. We examine in detail the derivation of musculotendon parameters in six muscle architecture datasets and four prominent OpenSim models of the lower limb, and then identify simplifications which could add uncertainties to the derived parameter values. Finally, we analyze the sensitivity of muscle force estimation to these parameters both numerically and analytically. Nine typical simplifications in parameter derivation are identified. Partial derivatives of the Hill-type contraction dynamics are derived. Tendon slack length is determined as the musculotendon parameter that muscle force estimation is most sensitive to, whereas pennation angle is the least impactful. Anatomical measurements alone are not enough to calibrate musculotendon parameters, and the improvement on muscle force estimation accuracy will be limited if the source muscle architecture datasets are the only main update. Model users may check if a dataset or model is free of concerning factors for their research or application requirements. The derived partial derivatives may be used as the gradient for musculotendon parameter calibration. For model development, we demonstrate that it is more promising to focus on other model parameters or components and seek alternative strategies to further increase simulation accuracy.
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Affiliation(s)
- Ziyu Chen
- Neuromuscular Diagnostics, Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany
- Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich, Munich, Germany
| | - David W Franklin
- Neuromuscular Diagnostics, Department of Sport and Health Sciences, Technical University of Munich, Munich, Germany.
- Munich Institute of Robotics and Machine Intelligence (MIRMI), Technical University of Munich, Munich, Germany.
- Munich Data Science Institute (MDSI), Technical University of Munich, Munich, Germany.
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Willson AM, Anderson AJ, Richburg CA, Muir BC, Czerniecki J, Steele KM, Aubin PM. Full body musculoskeletal model for simulations of gait in persons with transtibial amputation. Comput Methods Biomech Biomed Engin 2023; 26:412-423. [PMID: 35499924 PMCID: PMC9626388 DOI: 10.1080/10255842.2022.2065630] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
This paper describes the development, properties, and evaluation of a musculoskeletal model that reflects the anatomical and prosthetic properties of a transtibial amputee using OpenSim. Average passive prosthesis properties were used to develop CAD models of a socket, pylon, and foot to replace the lower leg. Additional degrees of freedom (DOF) were included in each joint of the prosthesis for potential use in a range of research areas, such as socket torque and socket pistoning. The ankle has three DOFs to provide further generality to the model. Seven transtibial amputee subjects were recruited for this study. 3 D motion capture, ground reaction force, and electromyographic (EMG) data were collected while participants wore their prescribed prosthesis, and then a passive prototype prosthesis instrumented with a 6-DOF load cell in series with the pylon. The model's estimates of the ankle, knee, and hip kinematics comparable to previous studies. The load cell provided an independent experimental measure of ankle joint torque, which was compared to inverse dynamics results from the model and showed a 7.7% mean absolute error. EMG data and muscle outputs from OpenSim's Static Optimization tool were qualitatively compared and showed reasonable agreement. Further improvements to the muscle characteristics or prosthesis-specific foot models may be necessary to better characterize individual amputee gait. The model is open-source and available at (https://simtk.org/projects/biartprosthesis) for other researchers to use to advance our understanding and amputee gait and assist with the development of new lower limb prostheses.
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Affiliation(s)
- Andrea M. Willson
- Department of Mechanical Engineering, University of Washington, Seattle WA, USA,VA RR&D Center for Limb Loss and MoBility (CLiMB), Seattle WA, USA
| | - Anthony J. Anderson
- Department of Mechanical Engineering, University of Washington, Seattle WA, USA,VA RR&D Center for Limb Loss and MoBility (CLiMB), Seattle WA, USA
| | | | - Brittney C. Muir
- Department of Mechanical Engineering, University of Washington, Seattle WA, USA,VA RR&D Center for Limb Loss and MoBility (CLiMB), Seattle WA, USA
| | - Joseph Czerniecki
- VA RR&D Center for Limb Loss and MoBility (CLiMB), Seattle WA, USA,Department of Rehabilitation Medicine, University of Washington, Seattle WA, USA
| | - Katherine M. Steele
- Department of Mechanical Engineering, University of Washington, Seattle WA, USA
| | - Patrick M. Aubin
- Department of Mechanical Engineering, University of Washington, Seattle WA, USA,VA RR&D Center for Limb Loss and MoBility (CLiMB), Seattle WA, USA
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Kainz H, Jonkers I. Imaging-based musculoskeletal models alter muscle and joint contact forces but do not improve the agreement with experimentally measured electromyography signals in children with cerebral palsy. Gait Posture 2023; 100:91-95. [PMID: 36502666 DOI: 10.1016/j.gaitpost.2022.11.019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2022] [Revised: 11/15/2022] [Accepted: 11/29/2022] [Indexed: 12/02/2022]
Abstract
BACKGROUND Musculoskeletal simulations are used to estimate muscle-tendon and joint contact forces (JCF). Personalizing the model's femoral geometry has been shown to improve the accuracy of JCF calculations. It is, however, unknown if the personalized geometry improves the agreement between estimated muscle activations and experimentally measured electromyography (EMG) signals. RESEARCH QUESTION Does personalizing the musculoskeletal geometry improve the agreement between estimated muscle activations and EMG signals in terms of timing? METHODS We retrospectively analysed data from Bosmans et al. [5], which included three-dimensional motion capture data, EMG signals of eight lower limb muscles on each leg, and magnetic resonance imaging (MRI) data from seven children with cerebral palsy. For each patient we created a generic-scaled model and MRI-based model, which accounted for the subject-specific musculoskeletal geometry. We calculated muscle activations, muscle-tendon forces and JCF. Muscle activations were compared to the EMG signals using coefficient of determination and cosines similarity. RESULTS MRI-based models altered the magnitude of muscle activations and had a large impact on JCF but did not change the muscle activations profiles and therefore did not improve the agreement with EMG signals. SIGNIFICANCE MRI-based models do not alter the shape of muscle activations. Hence, if detailed muscle activations are a desired output of the simulations, EMG-informed modeling approaches should be used for musculoskeletal simulation in children with cerebral palsy. Furthermore, our study highlighted that altered JCF does not necessarily mean accurate muscle activations. To improve patient-specific simulations, future work should focus on developing methods to estimate cost functions representative for the neural control of children with cerebral palsy.
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Affiliation(s)
- Hans Kainz
- Centre for Sport Science and University Sports, Department of Biomechanics, Kinesiology and Computer Science in Sport, Neuromechanics Research Group, University of Vienna, Austria.
| | - Ilse Jonkers
- Department of Movement Science, Human Movement Biomechanics Research Group, KU Leuven, Belgium
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Lee MR, Hicks JL, Wren TAL, Delp SL. Independently ambulatory children with spina bifida experience near-typical knee and ankle joint moments and forces during walking. Gait Posture 2023; 99:1-8. [PMID: 36283301 PMCID: PMC9772073 DOI: 10.1016/j.gaitpost.2022.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 08/12/2022] [Accepted: 10/16/2022] [Indexed: 12/14/2022]
Abstract
BACKGROUND Spina bifida, a neurological defect, can result in lower-limb muscle weakness. Altered ambulation and reduced musculoskeletal loading can yield decreased bone strength in individuals with spina bifida, yet individuals who remain ambulatory can exhibit normal bone outcomes. RESEARCH QUESTION During walking, how do lower-limb joint kinematics and moments and tibial forces in independently ambulatory children with spina bifida differ from those of children with typical development? METHODS We retrospectively analyzed data from 16 independently ambulatory children with spina bifida and 16 children with typical development and confirmed that tibial bone strength was similar between the two groups. Plantar flexor muscle strength was measured by manual muscle testing, and 14 of the children with spina bifida wore activity monitors for an average of 5 days. We estimated tibial forces at the knee and ankle using motion capture data and musculoskeletal simulations. We used Statistical Parametric Mapping t-tests to compare lower-limb joint kinematic and kinetic waveforms between the groups with spina bifida and typical development. Within the group with spina bifida, we examined relationships between plantar flexor muscle strength and peak tibial forces by calculating Spearman correlations. RESULTS Activity monitors from the children with spina bifida reported typical daily steps (9656 [SD 3095]). Despite slower walking speeds (p = 0.004) and altered lower-body kinematics (p < 0.001), children with spina bifida had knee and ankle joint moments and forces similar to those of children with typical development, with no detectable differences during stance. Plantar flexor muscle weakness was associated with increased compressive knee force (p = 0.002) and shear ankle force (p = 0.009). SIGNIFICANCE High-functioning, independently ambulatory children with spina bifida exhibited near-typical tibial bone strength and near-typical step counts and tibial load magnitudes. Our results suggest that the tibial forces in this group are of sufficient magnitudes to support the development of normal tibial bone strength.
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Affiliation(s)
- Marissa R Lee
- Department of Mechanical Engineering, Stanford University, 318 Campus Drive, Stanford, CA 94305, USA.
| | - Jennifer L Hicks
- Department of Bioengineering, Stanford University, 318 Campus Drive, Stanford, CA 94305, USA.
| | - Tishya A L Wren
- Children's Orthopaedic Center, Children's Hospital Los Angeles, 4650 Sunset Blvd, Los Angeles, CA 90027, USA.
| | - Scott L Delp
- Department of Mechanical Engineering, Stanford University, 318 Campus Drive, Stanford, CA 94305, USA; Department of Bioengineering, Stanford University, 318 Campus Drive, Stanford, CA 94305, USA.
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Koller W, Gonçalves B, Baca A, Kainz H. Intra- and inter-subject variability of femoral growth plate stresses in typically developing children and children with cerebral palsy. Front Bioeng Biotechnol 2023; 11:1140527. [PMID: 36911204 PMCID: PMC9999378 DOI: 10.3389/fbioe.2023.1140527] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 02/14/2023] [Indexed: 03/14/2023] Open
Abstract
Little is known about the influence of mechanical loading on growth plate stresses and femoral growth. A multi-scale workflow based on musculoskeletal simulations and mechanobiological finite element (FE) analysis can be used to estimate growth plate loading and femoral growth trends. Personalizing the model in this workflow is time-consuming and therefore previous studies included small sample sizes (N < 4) or generic finite element models. The aim of this study was to develop a semi-automated toolbox to perform this workflow and to quantify intra-subject variability in growth plate stresses in 13 typically developing (TD) children and 12 children with cerebral palsy (CP). Additionally, we investigated the influence of the musculoskeletal model and the chosen material properties on the simulation results. Intra-subject variability in growth plate stresses was higher in cerebral palsy than in typically developing children. The highest osteogenic index (OI) was observed in the posterior region in 62% of the TD femurs while in children with CP the lateral region was the most common (50%). A representative reference osteogenic index distribution heatmap generated from data of 26 TD children's femurs showed a ring shape with low values in the center region and high values at the border of the growth plate. Our simulation results can be used as reference values for further investigations. Furthermore, the code of the developed GP-Tool ("Growth Prediction-Tool") is freely available on GitHub (https://github.com/WilliKoller/GP-Tool) to enable peers to conduct mechanobiological growth studies with larger sample sizes to improve our understanding of femoral growth and to support clinical decision making in the near future.
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Affiliation(s)
- Willi Koller
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.,Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.,Vienna Doctoral School of Pharmaceutical, Nutritional and Sport Sciences, University of Vienna, Vienna, Austria
| | - Basílio Gonçalves
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.,Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Arnold Baca
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Hans Kainz
- Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.,Neuromechanics Research Group, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
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Personalisation of Plantarflexor Musculotendon Model Parameters in Children with Cerebral Palsy. Ann Biomed Eng 2022; 51:938-950. [PMID: 36380165 PMCID: PMC10122634 DOI: 10.1007/s10439-022-03107-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Accepted: 10/28/2022] [Indexed: 11/17/2022]
Abstract
AbstractNeuromusculoskeletal models can be used to evaluate aberrant muscle function in cerebral palsy (CP), for example by estimating muscle and joint contact forces during gait. However, to be accurate, models should include representative musculotendon parameters. We aimed to estimate personalised parameters that capture the mechanical behaviour of the plantarflexors in children with CP and typically developing (TD) children. Ankle angle (using motion capture), torque (using a load-cell), and medial gastrocnemius fascicle lengths (using ultrasound) were measured during slow passive ankle dorsiflexion rotation for thirteen children with spastic CP and thirteen TD children. Per subject, the measured rotation was input to a scaled OpenSim model to simulate the torque and fascicle length output. Musculotendon model parameters were personalised by the best match between simulated and experimental torque–angle and fascicle length-angle curves according to a least-squares fit. Personalised tendon slack lengths were significantly longer and optimal fibre lengths significantly shorter in CP than model defaults and than in TD. Personalised tendon compliance was substantially higher in both groups compared to the model default. The presented method to personalise musculotendon parameters will likely yield more accurate simulations of subject-specific muscle mechanics, to help us understand the effects of altered musculotendon properties in CP.
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Hosseini Nasab SH, Smith CR, Maas A, Vollenweider A, Dymke J, Schütz P, Damm P, Trepczynski A, Taylor WR. Uncertainty in Muscle–Tendon Parameters can Greatly Influence the Accuracy of Knee Contact Force Estimates of Musculoskeletal Models. Front Bioeng Biotechnol 2022; 10:808027. [PMID: 35721846 PMCID: PMC9204520 DOI: 10.3389/fbioe.2022.808027] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 05/03/2022] [Indexed: 01/07/2023] Open
Abstract
Understanding the sources of error is critical before models of the musculoskeletal system can be usefully translated. Using in vivo measured tibiofemoral forces, the impact of uncertainty in muscle–tendon parameters on the accuracy of knee contact force estimates of a generic musculoskeletal model was investigated following a probabilistic approach. Population variability was introduced to the routine musculoskeletal modeling framework by perturbing input parameters of the lower limb muscles around their baseline values. Using ground reaction force and skin marker trajectory data collected from six subjects performing body-weight squat, the knee contact force was calculated for the perturbed models. The combined impact of input uncertainties resulted in a considerable variation in the knee contact force estimates (up to 2.1 BW change in the predicted force), especially at larger knee flexion angles, hence explaining up to 70% of the simulation error. Although individual muscle groups exhibited different contributions to the overall error, variation in the maximum isometric force and pathway of the muscles showed the highest impacts on the model outcomes. Importantly, this study highlights parameters that should be personalized in order to achieve the best possible predictions when using generic musculoskeletal models for activities involving deep knee flexion.
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Affiliation(s)
- Seyyed Hamed Hosseini Nasab
- Laboratory for Movement Biomechanics, ETH Zürich, Zürich, Switzerland
- *Correspondence: Seyyed Hamed Hosseini Nasab, ; William R. Taylor,
| | - Colin R. Smith
- Laboratory for Movement Biomechanics, ETH Zürich, Zürich, Switzerland
| | - Allan Maas
- Aesculap AG, Tuttlingen, Germany
- Department of Orthopaedic and Trauma Surgery, Ludwig Maximilians University Munich, Musculoskeletal University Center Munich (MUM), Campus Grosshadern, Munich, Germany
| | | | - Jörn Dymke
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Pascal Schütz
- Laboratory for Movement Biomechanics, ETH Zürich, Zürich, Switzerland
| | - Philipp Damm
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - Adam Trepczynski
- Julius Wolff Institute, Berlin Institute of Health at Charité—Universitätsmedizin Berlin, Berlin, Germany
| | - William R. Taylor
- Laboratory for Movement Biomechanics, ETH Zürich, Zürich, Switzerland
- *Correspondence: Seyyed Hamed Hosseini Nasab, ; William R. Taylor,
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13
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Evaluating Anthropometric Scaling of a Generic Adult Model to Represent Pediatric Shoulder Strength. J Biomech 2022; 141:111170. [DOI: 10.1016/j.jbiomech.2022.111170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2021] [Revised: 02/24/2022] [Accepted: 05/29/2022] [Indexed: 11/18/2022]
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14
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Individual muscle force–energy rate is altered during crouch gait: A neuro-musculoskeletal evaluation. J Biomech 2022; 139:111141. [DOI: 10.1016/j.jbiomech.2022.111141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 05/02/2022] [Accepted: 05/04/2022] [Indexed: 11/19/2022]
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15
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De Pieri E, Romkes J, Wyss C, Brunner R, Viehweger E. Altered Muscle Contributions are Required to Support the Stance Limb During Voluntary Toe-Walking. Front Bioeng Biotechnol 2022; 10:810560. [PMID: 35480978 PMCID: PMC9036482 DOI: 10.3389/fbioe.2022.810560] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2021] [Accepted: 03/02/2022] [Indexed: 01/02/2023] Open
Abstract
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.
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Affiliation(s)
- Enrico De Pieri
- Laboratory for Movement Analysis, University of Basel Children’s Hospital, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
- *Correspondence: Enrico De Pieri,
| | - Jacqueline Romkes
- Laboratory for Movement Analysis, University of Basel Children’s Hospital, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Christian Wyss
- Laboratory for Movement Analysis, University of Basel Children’s Hospital, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
| | - Reinald Brunner
- Laboratory for Movement Analysis, University of Basel Children’s Hospital, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
- Department of Paediatric Orthopaedics, University of Basel Children’s Hospital, Basel, Switzerland
| | - Elke Viehweger
- Laboratory for Movement Analysis, University of Basel Children’s Hospital, Basel, Switzerland
- Department of Biomedical Engineering, University of Basel, Basel, Switzerland
- Department of Paediatric Orthopaedics, University of Basel Children’s Hospital, Basel, Switzerland
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16
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Buehler C, Koller W, De Comtes F, Kainz H. Quantifying Muscle Forces and Joint Loading During Hip Exercises Performed With and Without an Elastic Resistance Band. Front Sports Act Living 2021; 3:695383. [PMID: 34497999 PMCID: PMC8419330 DOI: 10.3389/fspor.2021.695383] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 07/21/2021] [Indexed: 01/13/2023] Open
Abstract
An increase in hip joint contact forces (HJCFs) is one of the main contributing mechanical causes of hip joint pathologies, such as hip osteoarthritis, and its progression. The strengthening of the surrounding muscles of the joint is a way to increase joint stability, which results in the reduction of HJCF. Most of the exercise recommendations are based on expert opinions instead of evidence-based facts. This study aimed to quantify muscle forces and joint loading during rehabilitative exercises using an elastic resistance band (ERB). Hip exercise movements of 16 healthy volunteers were recorded using a three-dimensional motion capture system and two force plates. All exercises were performed without and with an ERB and two execution velocities. Hip joint kinematics, kinetics, muscle forces, and HJCF were calculated based on the musculoskeletal simulations in OpenSim. Time-normalized waveforms of the different exercise modalities were compared with each other and with reference values found during walking. The results showed that training with an ERB increases both target muscle forces and HJCF. Furthermore, the ERB reduced the hip joint range of motion during the exercises. The type of ERB used (soft vs. stiff ERB) and the execution velocity of the exercise had a minor impact on the peak muscle forces and HJCF. The velocity of exercise execution, however, had an influence on the total required muscle force. Performing hip exercises without an ERB resulted in similar or lower peak HJCF and lower muscle forces than those found during walking. Adding an ERB during hip exercises increased the peak muscle and HJCF but the values remained below those found during walking. Our workflow and findings can be used in conjunction with future studies to support exercise design.
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Affiliation(s)
- Callum Buehler
- Neuromechanics Research Group, Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Willi Koller
- Neuromechanics Research Group, Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Florentina De Comtes
- Neuromechanics Research Group, Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
| | - Hans Kainz
- Neuromechanics Research Group, Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria
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17
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Kipp K, Kim H. Force-length-velocity behavior and muscle-specific joint moment contributions during countermovement and squat jumps. Comput Methods Biomech Biomed Engin 2021; 25:688-697. [PMID: 34491147 DOI: 10.1080/10255842.2021.1973446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
The countermovement (CMJ) and squat (SJ) jump are common tasks used to assess neuromuscular performance. While much is known about joint-level differences between both tasks, not much is known about differences in muscle-level biomechanics. The purpose of this study was to calculate the forces, force-length-velocity behavior, and muscle-specific contributions to net joint moments (NJM) during CMJ and SJ. Eight basketball players performed maximal CMJ and SJ while motion capture and ground reaction force (GRF) data were recorded. A musculoskeletal model and static optimization algorithm computed muscles forces and force generating abilities of the soleus (SOL), gastrocnemii (GAS), vastii (VAS), rectus femoris (RF), hamstring (HAM), and gluteus maximus (GMAX) muscles during CMJ and SJ. In addition, the moments created by each muscle were calculated and studied in relation to the respective NJMs. CMJ were characterized by longer movement duration, but similar GRFs and jump heights as SJ. VAS and GMAX exhibited greater muscle forces and force generating abilities during CMJ, likely because of more optimal force-velocity behavior. In contrast, the HAM exhibited more favorable force-length behavior during SJ. Muscle moments during CMJ and SJ were similar, except for the HAM, which produced greater hip extension and knee flexion muscle moments during CMJ. Although muscle forces and force generating abilities of the VAS and GMAX were greater during CMJ, more optimal force-length behavior and greater muscle moment contribution to knee NJM by the HAM during SJ appear to balance such that overall GRF and jump height remain similar regardless of jump task.
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Affiliation(s)
- Kristof Kipp
- Department of Physical Therapy - Program in Exercise Science, Marquette University, Milwaukee, Wisconsin, USA
| | - Hoon Kim
- Joint Department of Biomedical Engineering, University of North Carolina System, Chapel Hill, North Carolina, USA
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18
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Koller W, Baca A, Kainz H. Impact of scaling errors of the thigh and shank segments on musculoskeletal simulation results. Gait Posture 2021; 87:65-74. [PMID: 33894464 DOI: 10.1016/j.gaitpost.2021.02.016] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Revised: 01/12/2021] [Accepted: 02/15/2021] [Indexed: 02/02/2023]
Abstract
BACKGROUND Musculoskeletal simulations are widely used in the research community. The locations of surface markers are mostly used to scale a generic model to the participant's anthropometry. Marker-based scaling approaches include errors due to inaccuracies in marker placements. RESEARCH QUESTION How do scaling errors of the thigh and shank segments influence simulation results? METHODS Motion capture data and magnetic resonance images from a child with cerebral palsy and a typically developing child were used to create a subject-specific reference model for each child. These reference models were modified to mimic scaling errors due to inaccurately placed lateral epicondyle markers, which are frequently used to scale the thigh and shank segments. The thigh length was altered in 1 % steps from the original length and the shank length was accordingly adjusted to keep the total leg length constant. Thirty additional models were created, which included models with an altered thigh length of ±15 %. Subsequently, musculoskeletal simulations with OpenSim were performed with all models. Joint kinematics, joint kinetics, muscle forces and joint contact forces (JCF) were compared between the reference and altered models. RESULTS The investigated scaling error influenced joint kinematics and joint kinetics by up to 9.4° (hip flexion angle) and 0.15 Nm/kg (knee flexion moment), respectively. Maximum muscle and JCF differences of 46 % (medial gastrocnemius) and 72 % (hip JCF) bodyweight, respectively, were observed between the reference and altered models. Scaling errors mainly changed the magnitude but not the shape of most analyzed parameters. The influence of scaling errors on simulation results were similar in both participants. SIGNIFICANCE Scaling errors of the thigh segment influence simulation results at all joints due to the global optimization approach used in musculoskeletal simulations. Our findings can be used to estimate potential errors due to marker-based scaling approaches in previous and future studies.
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Affiliation(s)
- Willi Koller
- Centre for Sport Science and University Sports, Department of Biomechanics, Kinesiology and Computer Science in Sport, University of Vienna, Vienna, Austria.
| | - Arnold Baca
- Centre for Sport Science and University Sports, Department of Biomechanics, Kinesiology and Computer Science in Sport, University of Vienna, Vienna, Austria
| | - Hans Kainz
- Centre for Sport Science and University Sports, Department of Biomechanics, Kinesiology and Computer Science in Sport, University of Vienna, Vienna, Austria
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19
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Ma Y, Jiang S, Mithraratne K, Wilson N, Yu Y, Zhang Y. The effect of musculoskeletal model scaling methods on ankle joint kinematics and muscle force prediction during gait for children with cerebral palsy and equinus gait. Comput Biol Med 2021; 134:104436. [PMID: 33984750 DOI: 10.1016/j.compbiomed.2021.104436] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 04/21/2021] [Accepted: 04/21/2021] [Indexed: 10/21/2022]
Abstract
Clinical gait analysis incorporated with neuromusculoskeletal modelling could provide valuable information about joint movements and muscle functions during ambulation for children with cerebral palsy (CP). This study investigated how imposing pre-calculated joint angles during musculoskeletal model scaling influence the ankle joint angle and muscle force computation. Ten children with CP and equinus gait underwent clinical gait analysis. For each participant, a "default" (scaled without pre-calculated joint angles) and a "PJA" (scaled with pre-calculated ankle joint angles) model were generated to simulate their gait. Ankle joint angles were calculated with an inverse kinematic (IK) and direct kinematic (DK) approach. Triceps surae and tibialis anterior muscle forces were predicted by static optimisation and EMG-assisted modelling. We found that PJA-derived ankle angles showed a better agreement with what derived from the DK approach. The tibialis anterior muscle prediction was more likely to be affected by the scaling methods for the static optimisation approach and the gastrocnemius muscle force prediction was more likely to be influenced for the EMG-assisted modelling. This study recommends using the PJA model since the good consistency between IK and DK-derived joint angles facilitates communication among different research disciplines.
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Affiliation(s)
- Yunru Ma
- Department of Exercise Sciences, The University of Auckland, Auckland, New Zealand
| | - Shuyun Jiang
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Kumar Mithraratne
- Auckland Bioengineering Institute, The University of Auckland, Auckland, New Zealand
| | - Nichola Wilson
- Department of Surgery, The University of Auckland, Auckland, New Zealand
| | - Yan Yu
- Yueyang Hospital of Integrated Traditional Chinese and Western Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Yanxin Zhang
- Department of Exercise Sciences, The University of Auckland, Auckland, New Zealand.
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20
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Darras N, Nikaina E, Tziomaki M, Gkrimas G, Papavasiliou A, Pasparakis D. Development of Lower Extremity Strength in Ambulatory Children With Bilateral Spastic Cerebral Palsy in Comparison With Typically Developing Controls Using Absolute and Normalized to Body Weight Force Values. Front Neurol 2021; 12:617971. [PMID: 33815249 PMCID: PMC8017198 DOI: 10.3389/fneur.2021.617971] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 02/15/2021] [Indexed: 11/13/2022] Open
Abstract
This cross-sectional study aimed to examine the development of lower limb voluntary strength in 160 ambulatory patients with bilateral spastic cerebral palsy (CP) (106 diplegics/54 quadriplegics) and 86 typically developing (TD) controls, aged 7–16 years. Handheld dynamometry was used to measure isometric strength of seven muscle groups (hip adductors and abductors, hip extensors and flexors, knee extensors and flexors, and ankle dorsiflexors); absolute force (AF) values in pounds were collected, which were then normalized to body weight (NF). AF values increased with increasing age (p < 0.001 for all muscle groups), whereas NF values decreased through adolescence (p < 0.001 for all muscle groups except for hip abduction where p = 0.022), indicating that increases in weight through adolescence led to decreases in relative force. Both AF and NF values were significantly greater in TD subjects when compared with children with CP in all muscle and all age groups (p < 0.001). Diplegics and quadriplegics demonstrated consistently lower force values than TD subjects for all muscle groups, except for the hip extensors where TD children had similar values with diplegics (p = 0.726) but higher than quadriplegics (p = 0.001). Diplegic patients also exhibited higher values than quadriplegics in all muscles, except for the knee extensors where their difference was only indicative (p = 0.056). The conversion of CP subjects' force values as a percentage of the TD subjects' mean value revealed a pattern of significant muscle strength imbalance between the CP antagonist muscles, documented from the following deficit differences for the CP muscle couples: (hip extensors 13%) / (hip flexors 32%), (adductors 27%) / (abductors 52%), and (knee extensors 37%) / (knee flexors 53%). This pattern was evident in all age groups. Similarly, significant force deficiencies were identified in GMFCS III/IV patients when compared with TD children and GMFCS I/II patients. In this study, we demonstrated that children and adolescents with bilateral CP exhibited lower strength values in lower limb muscles when compared with their TD counterparts. This difference was more prevalent in quadriplegic patients and those with a more severe impairment. An important pattern of muscle strength imbalance between the antagonist muscles of the CP subjects was revealed.
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Affiliation(s)
| | - Eirini Nikaina
- First Department of Pediatrics, "Aghia Sophia" Children's Hospital, University of Athens, Athens, Greece
| | | | - Georgios Gkrimas
- Gait & Motion Analysis Center, ELEPAP, Athens, Greece.,Laboratory of Neuromuscular and Cardiovascular Study of Motion - LANECASM, Athens, Greece
| | | | - Dimitrios Pasparakis
- Gait & Motion Analysis Center, ELEPAP, Athens, Greece.,Pediatric Orthopaedic Department, Athens Medical Center, Athens, Greece
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21
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ARSLAN YUNUSZIYA, KARABULUT DERYA. SENSITIVITY OF MODEL-PREDICTED MUSCLE FORCES OF PATIENTS WITH CEREBRAL PALSY TO VARIATIONS IN MUSCLE-TENDON PARAMETERS. J MECH MED BIOL 2021. [DOI: 10.1142/s0219519421500081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Computational musculoskeletal modeling and simulation platforms are efficient tools to gain insight into the muscular coordination of patients with motor disabilities such as cerebral palsy (CP). Muscle force predictions from simulation programs are influenced by the architectural and contractile properties of muscle-tendon units. In this study, we aimed to evaluate the sensitivity of major lower limb muscle forces in patients with CP to changes in muscle-tendon parameters. Open-access datasets of children with CP ([Formula: see text]) and healthy children ([Formula: see text]) were considered. Monte Carlo analysis was executed to specify how sensitive the muscle forces to perturbations between [Formula: see text]% and [Formula: see text]% of the nominal value of the maximum isometric muscle force, optimal muscle fiber length, muscle pennation angle, tendon slack length, and maximum contraction velocity of muscle. The sensitivity analysis revealed that muscle forces of CP patients and healthy individuals were most sensitive to perturbations in the tendon slack length ([Formula: see text]), while forces of CP patients were more sensitive to tendon slack length when compared to the healthy group ([Formula: see text]). Muscle forces of patients and healthy individuals were insensitive to the other four parameters ([Formula: see text]), except for the gracilis and sartorius muscles in which the proportion of optimal muscle fiber length to tendon slack length is higher than 1; forces of these two muscles were also sensitive to the optimal muscle fiber length. The results of this study are expected to contribute to our understanding of which parameters should be personalized when conducting musculoskeletal modeling and simulation of patients with CP.
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Affiliation(s)
- YUNUS ZIYA ARSLAN
- Department of Robotics and Intelligent Systems, The Institute of the Graduate Studies in Science and Engineering, Turkish-German University, Beykoz, Istanbul 34820, Turkey
| | - DERYA KARABULUT
- Department of Mechanical Engineering, Istanbul University-Cerrahpasa, Avcilar, Istanbul 34320, Turkey
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22
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Vandekerckhove I, Wesseling M, Kainz H, Desloovere K, Jonkers I. The effect of hip muscle weakness and femoral bony deformities on gait performance. Gait Posture 2021; 83:280-286. [PMID: 33227606 DOI: 10.1016/j.gaitpost.2020.10.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Revised: 08/31/2020] [Accepted: 10/20/2020] [Indexed: 02/02/2023]
Abstract
BACKGROUND Children with cerebral palsy (CP) present with a pathological gait pattern due to musculoskeletal impairments, such as muscle weakness and altered bony geometry. However, the effect of these impairments on gait performance is still unknown. Research aim:This study aimed to explore the effect of hip muscle weakness and femoral deformities on the gait performance of CP and typical developing (TD) subjects. METHODS 6400 musculoskeletal models were created by weakening the hip extensors, abductors, adductors and flexors from 0% to 75 % and increasing the femoral anteversion angle (FAA) and neck shaft angle (NSA) from 20° to 60° and 120° to 160°, respectively. One TD and five CP gait patterns were imposed to each model and muscle forces were calculated. The effect of weakness and bony deformities on the capability gap (CG) at the hip, i.e. the lack in hip moment generating capacity to perform the gait pattern, was investigated using regression analysis. RESULTS The CG of apparent equinus, stiff knee gait, TD gait, jump gait and true equinus increased with 0.080, 0.038, 0.015, 0.023 and 0.005 Nm/kg per 10 percent hip abductor weakness increase, with 0.211, 0.130, 0.056, 0.045 and 0.011 Nm/kg per 10 degrees FAA increase and with 0.163, 0.080, 0.036, 0.043 and 0.011 Nm/kg per 10 degrees NSA increase, respectively. Combined weakness and bony deformities explained 96 %, 85 %, 82 %, 65 %, 40 % and 35 % of the variance in the CG of apparent equinus, TD gait, stiff knee gait, jump gait, true equinus and crouch gait, respectively. SIGNIFICANCE The results suggest that surgical correction of femoral deformities is more likely to be effective than strength training of hip muscles in enhancing CP gait performance. Jump gait, true equinus and especially crouch were more robust, while apparent equinus and stiff knee gait were limited by hip weakness and femoral deformities.
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Affiliation(s)
- Ines Vandekerckhove
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium; Clinical Motion Analysis Laboratory, University Hospitals Leuven, Pellenberg, Belgium.
| | | | - Hans Kainz
- Department of Movement Sciences, KU Leuven, Leuven, Belgium; Centre for Sport Science and University Sports, Department of Biomechanics, Kinesiology and Computer Science in Sport, University of Vienna, Vienna, Austria
| | - Kaat Desloovere
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium; Clinical Motion Analysis Laboratory, University Hospitals Leuven, Pellenberg, Belgium
| | - Ilse Jonkers
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
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23
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Montefiori E, Kalkman BM, Henson WH, Paggiosi MA, McCloskey EV, Mazzà C. MRI-based anatomical characterisation of lower-limb muscles in older women. PLoS One 2020; 15:e0242973. [PMID: 33259496 PMCID: PMC7707470 DOI: 10.1371/journal.pone.0242973] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 11/12/2020] [Indexed: 01/04/2023] Open
Abstract
The ability of muscles to produce force depends, among others, on their anatomical features and it is altered by ageing-associated weakening. However, a clear characterisation of these features, highly relevant for older individuals, is still lacking. This study hence aimed at characterising muscle volume, length, and physiological cross-sectional area (PCSA) and their variability, between body sides and between individuals, in a group of post-menopausal women. Lower-limb magnetic resonance images were acquired from eleven participants (69 (7) y. o., 66.9 (7.7) kg, 159 (3) cm). Twenty-three muscles were manually segmented from the images and muscle volume, length and PCSA were calculated from this dataset. Personalised maximal isometric force was then calculated using the latter information. The percentage difference between the muscles of the two lower limbs was up to 89% and 22% for volume and length, respectively, and up to 84% for PCSA, with no recognisable pattern associated with limb dominance. Between-subject coefficients of variation reached 36% and 13% for muscle volume and length, respectively. Generally, muscle parameters were similar to previous literature, but volumes were smaller than those from in-vivo young adults and slightly higher than ex-vivo ones. Maximal isometric force was found to be on average smaller than those obtained from estimates based on linear scaling of ex-vivo-based literature values. In conclusion, this study quantified for the first time anatomical asymmetry of lower-limb muscles in older women, suggesting that symmetry should not be assumed in this population. Furthermore, we showed that a scaling approach, widely used in musculoskeletal modelling, leads to an overestimation of the maximal isometric force for most muscles. This heavily questions the validity of this approach for older populations. As a solution, the unique dataset of muscle segmentation made available with this paper could support the development of alternative population-based scaling approaches, together with that of automatic tools for muscle segmentation.
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Affiliation(s)
- Erica Montefiori
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- * E-mail:
| | - Barbara M. Kalkman
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
| | - William H. Henson
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
| | - Margaret A. Paggiosi
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Oncology and Metabolism, Centre for Integrated research in Musculoskeletal Ageing, Mellanby Centre for Bone Research, University of Sheffield, Sheffield, United Kingdom
| | - Eugene V. McCloskey
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
- Department of Oncology and Metabolism, Centre for Integrated research in Musculoskeletal Ageing, Mellanby Centre for Bone Research, University of Sheffield, Sheffield, United Kingdom
| | - Claudia Mazzà
- Department of Mechanical Engineering, University of Sheffield, Sheffield, United Kingdom
- INSIGNEO Institute for in silico Medicine, University of Sheffield, Sheffield, United Kingdom
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Wesseling M, Kainz H, Hoekstra T, Van Rossom S, Desloovere K, De Groote F, Jonkers I. Botulinum toxin injections minimally affect modelled muscle forces during gait in children with cerebral palsy. Gait Posture 2020; 82:54-60. [PMID: 32892101 DOI: 10.1016/j.gaitpost.2020.08.122] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2019] [Revised: 07/10/2020] [Accepted: 08/18/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND Children with cerebral palsy (CP) present altered gait patterns and electromyography (EMG) activity compared to typically developing children. To temporarily reduce muscular activity and to correct the abnormal muscle force balance, Botulinum Toxin type A (BTX-A) injections are used. RESEARCH QUESTION What is the effect of BTX-A injections on dynamic muscle forces during gait, when calculated using an EMG-constrained approach?. METHODS Retrospective data of ten typically developing (TD) and fourteen children with spastic diplegic CP were used for musculoskeletal modeling and dynamic simulations of gait, before and after BTX-A treatment. Individual muscle forces were calculated using an EMG-constrained optimization, in which EMG of eight muscles was used as muscle excitation signal to constrain the muscle activation patterns. Paired t-tests were used to compare average modelled muscle forces in different phases of the gait cycle pre- and post-BTX-A, summarized in the muscle profile score. Two-sample t-tests were used to determine significant differences between TD and pre- and post-BTX-A modelled muscle forces. RESULTS For most muscles, the force was decreased in CP compared to TD children in all phases of the gait cycle, both before and after BTX-A treatment. Differences in muscle forces before and after BTX-A treatment were limited, with only few significant differences between pre- and post-BTX-A. Compared to a standard static optimization approach, imposing the EMG activity increased modelled muscle forces for most muscles. SIGNIFICANCE Our findings indicate that BTX-A treatment has a limited effect on the muscle balance in CP children. Besides that, the use of EMG-constrained optimization is recommended when studying muscle balance in children with CP.
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Affiliation(s)
- M Wesseling
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
| | - H Kainz
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium; Department of Biomechanics, Kinesiology and Computer Science in Sport, Centre for Sport Science and University Sports, University of Vienna, Vienna, Austria.
| | - T Hoekstra
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
| | - S Van Rossom
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
| | - K Desloovere
- Research Group for Neurorehabilitation, Department of Rehabilitation Sciences, KU, Leuven, Belgium.
| | - F De Groote
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
| | - I Jonkers
- Human Movement Biomechanics Research Group, Department of Movement Sciences, KU Leuven, Leuven, Belgium.
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Reimann H, Ramadan R, Fettrow T, Hafer JF, Geyer H, Jeka JJ. Interactions Between Different Age-Related Factors Affecting Balance Control in Walking. Front Sports Act Living 2020; 2:94. [PMID: 33345085 PMCID: PMC7739654 DOI: 10.3389/fspor.2020.00094] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Accepted: 07/12/2020] [Indexed: 12/30/2022] Open
Abstract
Maintaining balance during walking is a continuous sensorimotor control problem. Throughout the movement, the central nervous system has to collect sensory data about the current state of the body in space, use this information to detect possible threats to balance and adapt the movement pattern to ensure stability. Failure of this sensorimotor loop can lead to dire consequences in the form of falls, injury and death. Such failures tend to become more prevalent as people get older. While research has established a number of factors associated with higher risk of falls, we know relatively little about age-related changes of the underlying sensorimotor control loop and how such changes are related to empirically established risk factors. This paper approaches the problem of age-related fall risk from a neural control perspective. We begin by summarizing recent empirical findings about the neural control laws mapping sensory input to motor output for balance control during walking. These findings were established in young, neurotypical study populations and establish a baseline of sensorimotor control of balance. We then review correlates for deteriorating balance control in older adults, of muscle weakness, slow walking, cognitive decline, and increased visual dependency. While empirical associations between these factors and fall risk have been established reasonably well, we know relatively little about the underlying causal relationships. Establishing such causal relationships is hard, because the different factors all co-vary with age and are difficult to isolate empirically. One option to analyze the role of an individual factor for balance control is to use computational models of walking comprising all levels of the sensorimotor control loop. We introduce one such model that generates walking movement patterns from a short list of spinal reflex modules with limited supraspinal modulation for balance. We show how this model can be used to simulate empirical studies, and how comparison between the model and empirical results can indicate gaps in our current understanding of balance control. We also show how different aspects of aging can be added to this model to study their effect on balance control in isolation.
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Affiliation(s)
- Hendrik Reimann
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States
| | - Rachid Ramadan
- Institute for Neural Computation, Ruhr University, Bochum, Germany
| | - Tyler Fettrow
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States
- Department of Applied Physiology and Kinesiology, University of Florida, Gainesville, FL, United States
| | - Jocelyn F. Hafer
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States
| | - Hartmut Geyer
- Robotics Institute, Carnegie Mellon University, Pittsburgh, PA, United States
| | - John J. Jeka
- Department of Kinesiology and Applied Physiology, University of Delaware, Newark, DE, United States
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26
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A multi-scale modelling framework combining musculoskeletal rigid-body simulations with adaptive finite element analyses, to evaluate the impact of femoral geometry on hip joint contact forces and femoral bone growth. PLoS One 2020; 15:e0235966. [PMID: 32702015 PMCID: PMC7377390 DOI: 10.1371/journal.pone.0235966] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 06/25/2020] [Indexed: 11/23/2022] Open
Abstract
Multi-scale simulations, combining muscle and joint contact force (JCF) from musculoskeletal simulations with adaptive mechanobiological finite element analysis, allow to estimate musculoskeletal loading and predict femoral growth in children. Generic linearly scaled musculoskeletal models are commonly used. This approach, however, neglects subject- and age-specific musculoskeletal geometry, e.g. femoral neck-shaft angle (NSA) and anteversion angle (AVA). This study aimed to evaluate the impact of proximal femoral geometry, i.e. altered NSA and AVA, on hip JCF and femoral growth simulations. Musculoskeletal models with NSA ranging from 120° to 150° and AVA ranging from 20° to 50° were created and used to calculate muscle and hip JCF based on the gait analysis data of a typically developing child. A finite element model of a paediatric femur was created from magnetic resonance images. The finite element model was morphed to the geometries of the different musculoskeletal models and used for mechanobiological finite element analysis to predict femoral growth trends. Our findings showed that hip JCF increase with increasing NSA and AVA. Furthermore, the orientation of the hip JCF followed the orientation of the femoral neck axis. Consequently, the osteogenic index, which is a function of cartilage stresses and defines the growth rate, barely changed with altered NSA and AVA. Nevertheless, growth predictions were sensitive to the femoral geometry due to changes in the predicted growth directions. Altered NSA had a bigger impact on the growth results than altered AVA. Growth simulations based on mechanobiological principles were in agreement with reported changes in paediatric populations.
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27
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Charles JP, Grant B, D'Août K, Bates KT. Subject-specific muscle properties from diffusion tensor imaging significantly improve the accuracy of musculoskeletal models. J Anat 2020; 237:941-959. [PMID: 32598483 PMCID: PMC7542200 DOI: 10.1111/joa.13261] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2020] [Revised: 04/21/2020] [Accepted: 05/29/2020] [Indexed: 11/29/2022] Open
Abstract
Musculoskeletal modelling is an important platform on which to study the biomechanics of morphological structures in vertebrates and is widely used in clinical, zoological and palaeontological fields. The popularity of this approach stems from the potential to non-invasively quantify biologically important but difficult-to-measure functional parameters. However, while it is known that model predictions are highly sensitive to input values, it is standard practice to build models by combining musculoskeletal data from different sources resulting in 'generic' models for a given species. At present, there are little quantitative data on how merging disparate anatomical data in models impacts the accuracy of these functional predictions. This issue is addressed herein by quantifying the accuracy of both subject-specific human limb models containing individualised muscle force-generating properties and models built using generic properties from both elderly and young individuals, relative to experimental muscle torques obtained from an isokinetic dynamometer. The results show that subject-specific models predict isokinetic muscle torques to a greater degree of accuracy than generic models at the ankle (root-mean-squared error - 7.9% vs. 49.3% in elderly anatomy-based models), knee (13.2% vs. 57.3%) and hip (21.9% vs. 32.8%). These results have important implications for the choice of musculoskeletal properties in future modelling studies, and the relatively high level of accuracy achieved in the subject-specific models suggests that such models can potentially address questions about inter-subject variations of muscle functions. However, despite relatively high levels of overall accuracy, models built using averaged generic muscle architecture data from young, healthy individuals may lack the resolution and accuracy required to study such differences between individuals, at least in certain circumstances. The results do not wholly discourage the continued use of averaged generic data in musculoskeletal modelling studies but do emphasise the need for to maximise the accuracy of input values if studying intra-species form-function relationships in the musculoskeletal system.
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Affiliation(s)
- James P Charles
- Department of Musculoskeletal and Ageing Science , Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Barbara Grant
- Department of Musculoskeletal and Ageing Science , Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Kristiaan D'Août
- Department of Musculoskeletal and Ageing Science , Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
| | - Karl T Bates
- Department of Musculoskeletal and Ageing Science , Institute of Life Course and Medical Sciences, University of Liverpool, Liverpool, UK
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28
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Pitto L, Kainz H, Falisse A, Wesseling M, Van Rossom S, Hoang H, Papageorgiou E, Hallemans A, Desloovere K, Molenaers G, Van Campenhout A, De Groote F, Jonkers I. SimCP: A Simulation Platform to Predict Gait Performance Following Orthopedic Intervention in Children With Cerebral Palsy. Front Neurorobot 2019; 13:54. [PMID: 31379550 PMCID: PMC6650580 DOI: 10.3389/fnbot.2019.00054] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Accepted: 07/03/2019] [Indexed: 12/19/2022] Open
Abstract
Gait deficits in cerebral palsy (CP) are often treated with a single-event multi-level surgery (SEMLS). Selecting the treatment options (combination of bony and soft tissue corrections) for a specific patient is a complex endeavor and very often treatment outcome is not satisfying. A deterioration in 22.8% of the parameters describing gait performance has been reported and there is need for additional surgery in 11% of the patients. Computational simulations based on musculoskeletal models that allow clinicians to test the effects of different treatment options before surgery have the potential to drastically improve treatment outcome. However, to date, no such simulation and modeling method is available. Two important challenges are the development of methods to include patient-specific neuromechanical impairments into the models and to simulate the effect of different surgical procedures on post-operative gait performance. Therefore, we developed the SimCP framework that allows the evaluation of the effect of different simulated surgeries on gait performance of a specific patient and includes a graphical user interface (GUI) that enables performing virtual surgery on the models. We demonstrated the potential of our framework for two case studies. Models reflecting the patient-specific musculoskeletal geometry and muscle properties are generated based solely on data collected before the treatment. The patient's motor control is described based on muscle synergies derived from pre-operative EMG. The GUI is then used to modify the musculoskeletal properties according to the surgical plan. Since SEMLS does not affect motor control, the same motor control model is used to define gait performance pre- and post-operative. We use the capability gap (CG), i.e., the difference between the joint moments needed to perform healthy walking and the joint moments the personalized model can generate, to quantify gait performance. In both cases, the CG was smaller post- then pre-operative and this was in accordance with the measured change in gait kinematics after treatment.
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Affiliation(s)
- Lorenzo Pitto
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Hans Kainz
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | | | | | - Sam Van Rossom
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Hoa Hoang
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
| | - Eirini Papageorgiou
- Department of Rehabilitation Sciences, Doctoral School of Biomedical Sciences, KU Leuven, Leuven, Belgium.,Clinical Motion Analysis Laboratory, University Hospitals Leuven, Leuven, Belgium
| | - Ann Hallemans
- Department of Rehabilitation Sciences and Physiotherapy, University of Antwerp, Antwerp, Belgium
| | - Kaat Desloovere
- Department of Rehabilitation Sciences, Doctoral School of Biomedical Sciences, KU Leuven, Leuven, Belgium.,Clinical Motion Analysis Laboratory, University Hospitals Leuven, Leuven, Belgium
| | - Guy Molenaers
- Department of Orthopedics, University Hospitals Leuven, Leuven, Belgium.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | - Anja Van Campenhout
- Department of Orthopedics, University Hospitals Leuven, Leuven, Belgium.,Department of Development and Regeneration, KU Leuven, Leuven, Belgium
| | | | - Ilse Jonkers
- Department of Movement Sciences, KU Leuven, Leuven, Belgium
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29
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Veerkamp K, Schallig W, Harlaar J, Pizzolato C, Carty CP, Lloyd DG, van der Krogt MM. The effects of electromyography-assisted modelling in estimating musculotendon forces during gait in children with cerebral palsy. J Biomech 2019; 92:45-53. [PMID: 31153626 DOI: 10.1016/j.jbiomech.2019.05.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 04/09/2019] [Accepted: 05/16/2019] [Indexed: 11/16/2022]
Abstract
Neuro-musculoskeletal modelling can provide insight into the aberrant muscle function during walking in those suffering cerebral palsy (CP). However, such modelling employs optimization to estimate muscle activation that may not account for disturbed motor control and muscle weakness in CP. This study evaluated different forms of neuro-musculoskeletal model personalization and optimization to estimate musculotendon forces during gait of nine children with CP (GMFCS I-II) and nine typically developing (TD) children. Data collection included 3D-kinematics, ground reaction forces, and electromyography (EMG) of eight lower limb muscles. Four different optimization methods estimated muscle activation and musculotendon forces of a scaled-generic musculoskeletal model for each child walking, i.e. (i) static optimization that minimized summed-excitation squared; (ii) static optimization with maximum isometric muscle forces scaled to body mass; (iii) an EMG-assisted approach using optimization to minimize summed-excitation squared while reducing tracking errors of experimental EMG-linear envelopes and joint moments; and (iv) EMG-assisted with musculotendon model parameters first personalized by calibration. Both static optimization approaches showed a relatively low model performance compared to EMG envelopes. EMG-assisted approaches performed much better, especially in CP, with only a minor mismatch in joint moments. Calibration did not affect model performance significantly, however it did affect musculotendon forces, especially in CP. A model more consistent with experimental measures is more likely to yield more physiologically representative results. Therefore, this study highlights the importance of calibrated EMG-assisted modelling when estimating musculotendon forces in TD children and even more so in children with CP.
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Affiliation(s)
- Kirsten Veerkamp
- Amsterdam UMC, Vrije Universiteit Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands; Vrije Universiteit Amsterdam, Department of Behavioral and Movement Sciences, Amsterdam Movement Sciences, the Netherlands; Gold Coast Centre for Orthopaedic Research, Engineering and Education (GCORE), Menzies Health Institute Queensland, Gold Coast, Australia.
| | - Wouter Schallig
- Amsterdam UMC, Vrije Universiteit Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands; Amsterdam UMC, Univ of Amsterdam, Radiology & Nuclear Medicine, Amsterdam Movement Sciences, Meibergdreef 9, Amsterdam, the Netherlands
| | - Jaap Harlaar
- Amsterdam UMC, Vrije Universiteit Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands; Delft University of Technology, Department of Biomechanical Engineering, Delft, the Netherlands
| | - Claudio Pizzolato
- Gold Coast Centre for Orthopaedic Research, Engineering and Education (GCORE), Menzies Health Institute Queensland, Gold Coast, Australia; School of Allied Health Sciences, Griffith University, Gold Coast, Australia
| | - Christopher P Carty
- Gold Coast Centre for Orthopaedic Research, Engineering and Education (GCORE), Menzies Health Institute Queensland, Gold Coast, Australia; Queensland Children's Motion Analysis Service, Children's Health Queensland Hospital and Health Service, Brisbane, Australia
| | - David G Lloyd
- Gold Coast Centre for Orthopaedic Research, Engineering and Education (GCORE), Menzies Health Institute Queensland, Gold Coast, Australia; School of Allied Health Sciences, Griffith University, Gold Coast, Australia
| | - Marjolein M van der Krogt
- Amsterdam UMC, Vrije Universiteit Amsterdam, Rehabilitation Medicine, Amsterdam Movement Sciences, de Boelelaan 1117, Amsterdam, the Netherlands
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30
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Kainz H, Hoang H, Pitto L, Wesseling M, Van Rossom S, Van Campenhout A, Molenaers G, De Groote F, Desloovere K, Jonkers I. Selective dorsal rhizotomy improves muscle forces during walking in children with spastic cerebral palsy. Clin Biomech (Bristol, Avon) 2019; 65:26-33. [PMID: 30953917 DOI: 10.1016/j.clinbiomech.2019.03.014] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2018] [Revised: 01/25/2019] [Accepted: 03/19/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND Selective dorsal rhizotomy aims to reduce spasticity in children with cerebral palsy. Early investigations indicated postoperative weakness, whereas more recent studies showed that selective dorsal rhizotomy either does not change or improves muscle strength. All previous studies assessed muscle strength in a static position, which did not represent the walking situation. The aim of this study was to analyze the influence of selective dorsal rhizotomy on muscle forces during gait. METHODS Motion capture data of 25 children with spastic cerebral palsy and 10 typically developing participants were collected. A musculoskeletal OpenSim model was used to calculate joint kinematics, joint kinetics and muscle forces during gait. Static optimization and an electromyography-informed approach to calculate muscle forces were compared. A Muscle-Force-Profile was introduced and used to compare the muscle forces during walking before and after a selective dorsal rhizotomy. FINDINGS Independent of the approach used (electromyography-informed versus static optimization), selective dorsal rhizotomy significantly normalized forces in spastic muscles during walking and did not reduce the contribution of non-spastic muscles. INTERPRETATION This study showed that selective dorsal rhizotomy improves dynamic muscle forces in children with cerebral palsy and leads to less gait pathology, as shown in the improvement in joint kinematics and joint kinetics. Individual muscle force analyses using the Muscle-Force-Profile extend standard joint kinematics and joint moment analyses, which might improve clinical-decision making in children with cerebral palsy in the future. The reference data of our participants and MATLAB code for the Muscle-Force-Profile are publicly available on simtk.org/projects/muscleprofile.
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Affiliation(s)
- Hans Kainz
- Department of Kinesiology, KU Leuven, Leuven, Belgium.
| | - Hoa Hoang
- Department of Kinesiology, KU Leuven, Leuven, Belgium
| | - Lorenzo Pitto
- Department of Kinesiology, KU Leuven, Leuven, Belgium
| | | | | | - Anja Van Campenhout
- Department of Development and Regeneration, University Hospital Leuven, Leuven, Belgium
| | - Guy Molenaers
- Department of Development and Regeneration, University Hospital Leuven, Leuven, Belgium
| | | | - Kaat Desloovere
- Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium; Clinical Motion Analysis Laboratory, University Hospital Leuven, Leuven, Belgium
| | - Ilse Jonkers
- Department of Kinesiology, KU Leuven, Leuven, Belgium
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31
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Children with cerebral palsy have larger Achilles tendon moment arms than typically developing children. J Biomech 2019; 82:307-312. [DOI: 10.1016/j.jbiomech.2018.11.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2017] [Revised: 10/14/2018] [Accepted: 11/02/2018] [Indexed: 01/19/2023]
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