scholarly journals EMG-Driven Optimal Estimation of Subject-SPECIFIC Hill Model Muscle–Tendon Parameters of the Knee Joint Actuators

2017 ◽  
Vol 64 (9) ◽  
pp. 2253-2262 ◽  
Author(s):  
Tobias Heimann ◽  
François Chung ◽  
Hans Lamecker ◽  
Hervé Delingette

2019 ◽  
Vol 8 (11) ◽  
pp. 509-517 ◽  
Author(s):  
Kyoung-Tak Kang ◽  
Yong-Gon Koh ◽  
Kyoung-Mi Park ◽  
Chong-Hyuck Choi ◽  
Min Jung ◽  
...  

Objectives The aim of this study was to investigate the biomechanical effect of the anterolateral ligament (ALL), anterior cruciate ligament (ACL), or both ALL and ACL on kinematics under dynamic loading conditions using dynamic simulation subject-specific knee models. Methods Five subject-specific musculoskeletal models were validated with computationally predicted muscle activation, electromyography data, and previous experimental data to analyze effects of the ALL and ACL on knee kinematics under gait and squat loading conditions. Results Anterior translation (AT) significantly increased with deficiency of the ACL, ALL, or both structures under gait cycle loading. Internal rotation (IR) significantly increased with deficiency of both the ACL and ALL under gait and squat loading conditions. However, the deficiency of ALL was not significant in the increase of AT, but it was significant in the increase of IR under the squat loading condition. Conclusion The results of this study confirm that the ALL is an important lateral knee structure for knee joint stability. The ALL is a secondary stabilizer relative to the ACL under simulated gait and squat loading conditions. Cite this article: Bone Joint Res 2019;8:509–517.


2010 ◽  
Vol 13 (5) ◽  
pp. 589-603 ◽  
Author(s):  
N.H. Yang ◽  
P.K. Canavan ◽  
H. Nayeb-Hashemi ◽  
B. Najafi ◽  
A. Vaziri

Biomechanics ◽  
2021 ◽  
Vol 1 (3) ◽  
pp. 293-306
Author(s):  
Sentong Wang ◽  
Kazunori Hase ◽  
Susumu Ota

Finite element musculoskeletal (FEMS) approaches using concurrent musculoskeletal and finite element models driven by motion data such as marker-based motion trajectory can provide insight into the interactions between the knee joint secondary kinematics, contact mechanics, and muscle forces in subject-specific biomechanical investigations. However, these data-driven FEMS systems have a major disadvantage that makes them challenging to apply in clinical environments, i.e., they require expensive and inconvenient equipment for data acquisition. In this study, we developed an FEMS model of the lower limb driven solely by inertial measurement unit sensors that include the tissue geometries of the entire knee joint, and that combine modeling of 16 muscles into a single framework. The model requires only the angular velocities and accelerations measured by the sensors as input. The target outputs (knee contact mechanics, secondary kinematics, and muscle forces) are predicted from the convergence results of iterative calculations of muscle force optimization and knee contact mechanics. To evaluate its accuracy, the model was compared with in vivo experimental data during gait. The maximum contact pressure (11.3 MPa) occurred on the medial side of the cartilage at the maximum loading response. The developed framework combines measurement convenience and accurate modeling, and shows promise for clinical applications aimed at understanding subject-specific biomechanics.


2021 ◽  
Author(s):  
Abby E Peters ◽  
Brendan Geraghty ◽  
Karl T Bates ◽  
Riaz Akhtar ◽  
Rosti Readioff ◽  
...  

Background. Ligaments work to stabilize the human knee joint and prevent excessive movement. Whilst ligaments are known to decline in structure and function with aging, there has been no systematic effort to study changes in gross mechanical properties in the four major human knee ligaments due to osteoarthritis (OA). This study aims to collate material properties for the anterior (ACL) and posterior (PCL) cruciate ligaments, medial (MCL) and lateral (LCL) collateral ligaments. Our cadaveric samples come from a diverse demographic from which the effects of aging and OA on bone and cartilage material properties have already been quantified. Therefore, by combining our previous bone and cartilage data with the new ligament data from this study we are facilitating subject-specific whole-joint modelling studies. Methods. The demographics of the collected cadaveric knee joints were diverse with age range between 31 to 88 years old, and OA International Cartilage Repair Society grade 0 to 4. Twelve cadaveric human knee joints were dissected, and bone-ligament-bone specimens were extracted for mechanical loading to failure. Ligament material properties were determined from the load-extension curves, namely: linear and ultimate (failure) stress and strain, secant modulus, tangent modulus, and stiffness. Results. There were significant negative correlations between age and ACL linear force (p=0.01), stress (p=0.03) and extension (p=0.05), ACL failure force (p=0.02), stress (p=0.02) and extension (p=0.02), PCL secant (p=0.02) and tangent (p=0.02) modulus, and LCL stiffness (p=0.05). Significant negative correlations were also found between OA grades and ACL linear force (p=0.05), stress (p=0.02), extension (p=0.01) and strain (p=0.03), and LCL failure stress (p=0.05). However, changes in age or OA grade did not show a statistically significant correlation with the MCL tensile parameters. Trends showed that almost all the tensile parameters of the ACL and PCLs decreased with increasing age and progression of OA. Due to small sample size, the combined effect of age and presence of OA could not be statistically derived. Conclusions. This research is the first to correlate changes in tensile properties of the four major human knee ligaments to aging and OA. The current ligament study when combined with our previous findings on bone and cartilage for the same twelve knee cadavers, supports conceptualization of OA as a whole-joint disease that impairs the integrity of many peri-articular tissues within the knee. The subject-specific data pool consisting of the material properties of the four major knee ligaments, subchondral and trabecular bones and articular cartilage will aid reconstruction and graft replacements and advance knee joint finite element models, whilst knowledge of aged or diseased mechanics may direct future therapeutic interventions.


2020 ◽  
Vol 142 (6) ◽  
Author(s):  
David Leandro Dejtiar ◽  
Christine Mary Dzialo ◽  
Peter Heide Pedersen ◽  
Kenneth Krogh Jensen ◽  
Martin Kokholm Fleron ◽  
...  

Abstract Musculoskeletal (MS) models can be used to study the muscle, ligament, and joint mechanics of natural knees. However, models that both capture subject-specific geometry and contain a detailed joint model do not currently exist. This study aims to first develop magnetic resonance image (MRI)-based subject-specific models with a detailed natural knee joint capable of simultaneously estimating in vivo ligament, muscle, tibiofemoral (TF), and patellofemoral (PF) joint contact forces and secondary joint kinematics. Then, to evaluate the models, the predicted secondary joint kinematics were compared to in vivo joint kinematics extracted from biplanar X-ray images (acquired using slot scanning technology) during a quasi-static lunge. To construct the models, bone, ligament, and cartilage structures were segmented from MRI scans of four subjects. The models were then used to simulate lunges based on motion capture and force place data. Accurate estimates of TF secondary joint kinematics and PF translations were found: translations were predicted with a mean difference (MD) and standard error (SE) of 2.13 ± 0.22 mm between all trials and measures, while rotations had a MD ± SE of 8.57 ± 0.63 deg. Ligament and contact forces were also reported. The presented modeling workflow and the resulting knee joint model have potential to aid in the understanding of subject-specific biomechanics and simulating the effects of surgical treatment and/or external devices on functional knee mechanics on an individual level.


2020 ◽  
Vol 143 (1) ◽  
Author(s):  
Sarah Ward ◽  
Lukas Wiedemann ◽  
Kazuto Kora ◽  
Andrew McDaid

Abstract The relink trainer (RLT) is a novel end-effector device designed for gait-retraining poststroke. The user's foot is constrained to a specific kinematic trajectory relative to the trainer, while the hip and knee are unconstrained. As the RLT only fixes the footplate trajectory, the expected constraint on the hip and knee angles will be subject-specific due to individual lower limb geometries. This study had two objectives (1) to calculate the subject-specific theoretical joint angle trajectories, the RLT should constrain the hip and knee angle to using computer simulation, assuming a fixed hip position relative to the RLT, and (2) experimentally determine the actual hip and knee joint angle trajectories of healthy users walking in the RLT, and compare them to the theoretical joint angle trajectories. The root-mean-square (RMS) error between joint trajectories obtained from motion capture and simulation ranged from 4.31 deg to 20.51 deg for the hip and between 4.48 deg and 22.58 deg for the knee, suggestive of moderate to poor accuracy and distinct kinematic adaptation strategies when using the RLT. A linear fit method (LFM) was used to determine the similarity between the obtained and simulated joint angle trajectories. LFM results would suggest that users' hip and knee joint angles follow the simulated joint angle trajectories when walking in the RLT; however, the actual joint angle trajectories are offset from the simulation trajectories. Post hoc analyses suggest hip motion when using the RLT influences the hip and knee angle trajectory differences for participants.


2012 ◽  
Vol 31 (1) ◽  
pp. 10-22 ◽  
Author(s):  
Lasse P. Räsänen ◽  
Mika E. Mononen ◽  
Miika T. Nieminen ◽  
Eveliina Lammentausta ◽  
Jukka S. Jurvelin ◽  
...  

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