Quantifying Force Magnitude and Loading Rate from Drop Landings That Induce Osteogenesis

2001 ◽  
Vol 17 (2) ◽  
pp. 142-152 ◽  
Author(s):  
Jeremy J. Bauer ◽  
Robyn K. Fuchs ◽  
Gerald A. Smith ◽  
Christine M. Snow
Keyword(s):  
Hip Joint ◽  
Inverse Dynamics ◽  
Initial Contact ◽  
Ground Reaction Forces ◽  
Loading Rates ◽  
Impact Peak ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Drop Landings ◽  
Joint Reaction

Drop landings increase hip bone mass in children. However, force characteristics from these landings have not been studied. We evaluated ground and hip joint reaction forces, average loading rates, and changes across multiple trials from drop landings associated with osteogenesis in children. Thirteen prepubescent children who had previously participated in a bone loading program volunteered for testing. They performed 100 drop landings onto a force plate. Ground reaction forces (GRF) and two-dimensional kinematic data were recorded. Hip joint reaction forces were calculated using inverse dynamics. Maximum GRF were 8.5 ± 2.2 body weight (BW). At initial contact, GRF were 5.6 ± 1.4 BW while hip joint reactions were 4.7 ± 1.4 BW. Average loading rates for GRF were 472 ± 168 BW/s. Ground reaction forces did not change significantly across trials for the group. However, 5 individuals showed changes in max GRF across trials. Our data indicate that GRF are attenuated 19% to the hip at the first impact peak and 49% at the second impact peak. Given the skeletal response from the drop landing protocol and our analysis of the associated force magnitudes and average loading rates, we now have a data point on the response surface for future study of various combinations of force, rate, and number of load repetitions for increasing bone in children.

Influence of the Musculotendon Dynamics on the Muscle Force-Sharing Problem of the Shoulder—A Fully Inverse Dynamics Approach

2018 ◽  
Vol 140 (7) ◽  
Author(s):  
Quental Carlos ◽  
Azevedo Margarida ◽  
Ambrósio Jorge ◽  
Gonçalves S. B. ◽  
Folgado João
Keyword(s):  
Muscle Activation ◽  
Inverse Dynamics ◽  
Glenohumeral Joint ◽  
Inverse Dynamic ◽  
Force Sharing ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Muscle Activations ◽  
Joint Reaction

Abstract Most dynamic simulations are based on inverse dynamics, being the time-dependent physiological nature of the muscle properties rarely considered due to numerical challenges. Since the influence of muscle physiology on the consistency of inverse dynamics simulations remains unclear, the purpose of the present study is to evaluate the computational efficiency and biological validity of four musculotendon models that differ in the simulation of the muscle activation and contraction dynamics. Inverse dynamic analyses are performed using a spatial musculoskeletal model of the upper limb. The muscle force-sharing problem is solved for five repetitions of unloaded and loaded motions of shoulder abduction and shoulder flexion. The performance of the musculotendon models is evaluated by comparing muscle activation predictions with electromyography (EMG) signals, measured synchronously with motion for 11 muscles, and the glenohumeral joint reaction forces estimated numerically with those measured in vivo. The results show similar muscle activations for all muscle models. Overall, high cross-correlations are computed between muscle activations and the EMG signals measured for all movements analyzed, which provides confidence in the results. The glenohumeral joint reaction forces estimated compare well with those measured in vivo, but the influence of the muscle dynamics is found to be negligible. In conclusion, for slow-speed, standard movements of the upper limb, as those studied here, the activation and musculotendon contraction dynamics can be neglected in inverse dynamic analyses without compromising the prediction of muscle and joint reaction forces.

Generalized Constraint and Joint Reaction Forces in the Inverse Dynamics of Spatial Flexible Mechanical Systems

1994 ◽  
Vol 116 (3) ◽  
pp. 777-784 ◽  
Author(s):  
D. C. Chen ◽  
A. A. Shabana ◽  
J. Rismantab-Sany
Keyword(s):  
Inverse Dynamics ◽  
Mechanical Systems ◽  
Flexible Body ◽  
Body Dynamics ◽  
Joint Reaction Forces ◽  
Flexible Body Dynamics ◽  
Reaction Forces ◽  
Applied Forces ◽  
Generalized Constraint ◽  
Joint Reaction

In both the augmented and recursive formulations of the dynamic equations of flexible mechanical systems, the inerita, constraints, and applied forces must be properly defined. The inverse dynamics is a commonly used approach for the force analysis of mechanical systems. In this approach, the system is kinematically driven using specified motion trajectories, and the objective is to determine the driving forces and torques. In flexible body dynamics, however, a force that acts at a point on the deformable body is equipollent to a system, defined at another point, that consists of the same force, a moment that depends on the relative deformation between the two points, and a set of generalized forces associated with the elastic coordinates. Furthermore, a moment in flexible body dynamics is no longer a free vector. It is defined by the location of its line of action as well as its magnitude and direction. The joint reaction and generalized constraint forces represent equipollent systems of forces. Both systems in flexible body dynamics are function of the deformation. In this investigation, a procedure is developed for the determination of the joint reaction forces in spatial flexible mechanical systems. The mathematical formulation of some mechanical joints that are often encountered in the analysis of constrained flexible mechanical systems is discussed. Expressions for the generalized reaction forces in terms of the constraint Jacobian matrices of the joints are presented. The effect of the elastic deformation on the reaction forces is also examined numerically using the spatial flexible multibody RSSR mechanism that consists of a set of interconnected rigid and elastic bodies. The procedure described in this investigation can also be used to determine the joint torques and actuator forces in kinematically driven spatial elastic mechanism and manipulator systems.

Joint Reaction Forces at the Hip Joint during Dynamic Manipulation of the Femur

2008 ◽  
Author(s):  
Thomas R. Gardner ◽  
Katerina Fishman ◽  
Alaina Johns ◽  
Evan K. Johnson
Keyword(s):  
Hip Joint ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Joint Reaction ◽  
Dynamic Manipulation

Adaptation of the AnyBody™ Musculoskeletal Shoulder Model to the Nonconforming Total Shoulder Arthroplasty Context

2015 ◽  
Vol 137 (10) ◽  
Author(s):  
Lauranne Sins ◽  
Patrice Tétreault ◽  
Nicola Hagemeister ◽  
Natalia Nuño
Keyword(s):  
Contact Area ◽  
Shoulder Arthroplasty ◽  
Humeral Head ◽  
Inverse Dynamics ◽  
Center Of Pressure ◽  
Total Shoulder Arthroplasty ◽  
Strong Support ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Joint Reaction

Current musculoskeletal inverse dynamics shoulder models have two limitations to use in the context of nonconforming total shoulder arthroplasty (NC-TSA). First, the ball and socket glenohumeral (GH) joint simplification avoids any humeral head translations. Second, there is no contact at the GH joint to compute the contact area and the center of pressure (COP) between the two components of NC-TSA. In this paper, we adapted the AnyBody™ shoulder model by introducing humeral head translations and contact between the two components of an NC-TSA. Abduction in the scapular plane was considered. The main objective of this study was to adapt the AnyBody™ shoulder model to a NC-TSA context and to compare the results of our model (translations, COP, contact area, GH joint reaction forces (GH-JRFs), and muscular forces) with previous numerical, experimental, and clinical studies. Humeral head translations and contact were successfully introduced in our adapted shoulder model with strong support for our findings by previous studies.

scholarly journals Wearing Cushioning Shoes Reduce Load Rates More Effectively in Post-Fatigue than in Pre-Fatigue during Landings

Biology ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 962
Author(s):  
Xi Wang ◽  
Liqin Deng ◽  
Wing-Kai Lam ◽  
Yang Yang ◽  
Xini Zhang ◽  
...  
Keyword(s):  
Acute Exercise ◽  
Repeated Measure ◽  
Initial Contact ◽  
Significance Level ◽  
Loading Rates ◽  
Impact Forces ◽  
Before And After ◽  
Reaction Forces ◽  
Drop Landings ◽  
Exercise Induced

Purpose: this study aimed to investigate the footwear cushioning effects on impact forces and joint kinematics of the lower extremity during bipedal drop landings before and after acute exercise-induced fatigue protocol. Methods: in this case, 15 male collegiate basketball athletes performed drop landings from a 60 cm platform wearing highly-cushioned shoes (HS) and less cushioned shoes (control shoes, CS) before and after acute fatigue-inducing exercises (i.e., shuttle run combined with multiple vertical jumps). Force plates and motion capturing systems were synchronised to measure ground reaction forces and kinematic data during drop landings. Maximum jump height was analysed with one-way ANOVA. Two-way repeated measure ANOVAs were performed on each of the tested variables to examine if there was significant main effects of shoe and fatigue as well as the interaction. The significance level was set to 0.05. Results: rearfoot peak impact forces and loading rates significantly reduced when the participants wore HS in pre- and post-fatigue conditions. The peak loading rates in forefoot significantly reduced when HS were worn in post-fatigue. Compared with pre-fatigue, wearing HS contributed to with 24% and 13% reduction in forefoot and rearfoot peak loading rates, respectively, and the occurrence times of first and second peak impact forces and loading rates were much later. In the post-fatigue, a significant increase in the initial contact and minimum angles of the ankle were observed in HS compared with CS. Conclusion: these findings suggest that footwear cushioning can reduce landing-related rearfoot impact forces regardless of fatigue conditions. In a situation where the neuromuscular activity is reduced or absent such as post-fatigue wearing better cushioning shoes show superior attenuation, as indicated by lower forefoot and rearfoot impacts.

Dynamic Force Response of Human Legs due to Vertical Jumps

2011 ◽  
Author(s):  
Kinjal Prajapati ◽  
Fred Barez ◽  
James Kao ◽  
David Wagner
Keyword(s):  
Knee Joint ◽  
Hip Joint ◽  
Vertical Jump ◽  
Injury Mechanism ◽  
Ankle Injuries ◽  
Musculoskeletal Simulation ◽  
Joint Reaction Forces ◽  
Reaction Forces ◽  
Vertical Jumps ◽  
Joint Reaction

Jumping is a natural exertion that occurs during a variety of human activities including playing sports, working, skateboarding, dancing, escaping from hazardous events, rescue activities, and many others. During jumping, the ankles in particular are expected to support the entire body weight of the jumper and that may lead to ankle injuries. Each year hundreds of patients are treated for ankle sprains/strains with ankle fractures as one of the most common injuries treated by orthopedists and podiatrists. The knee joint is also considered the most-often injured joint in the entire human body. Although the general anatomy of the lower extremities is fairly well understood, an understanding of the injury mechanism during these jumping tasks is not well understood. The aim of this study is to determine the reaction forces exerted on legs and joints due to vertical jumps, through musculoskeletal simulation and experimental studies to better understand the dynamic jump process and the injury mechanism. The joint reaction forces and moments exerted on the ankle, knee and hip joint during takeoff and extreme squat landing of a vertical jump were determined through the application of musculoskeletal simulation. It is concluded that during extreme squat landing of a vertical jump, joint reaction forces and moments were highest in proximal/distal and anteroposterior direction may cause most likely injury to the hip joint ligaments, ankle fracture and knee joint, respectively.

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