Biomechanical Study of Symmetric Bending and Lifting Behavior in Weightlifter with Lumbar L4-L5 Disc Herniation and Physiological Straightening Using Finite Element Simulation.

Background: Physiological curvature changes of the lumbar spine and disc herniation can cause abnormal biomechanical responses of the lumbar spine. Finite element (FE) studies on special weightlifter models are limited, yet understanding stress in damaged lumbar spines is crucial for preventing and rehabilitating lumbar diseases. This study analyzes the biomechanical responses of a weightlifter with lumbar straightening and L4-L5 disc herniation during symmetric bending and lifting to optimize training and rehabilitation.

Structural and Organizational Strategies of Locomotor Modules during Landing in Patients with Chronic Ankle Instability.

Background: Human locomotion involves the coordinated activation of a finite set of modules, known as muscle synergy, which represent the motor control strategy of the central nervous system. However, most prior studies have focused on isolated muscle activation, overlooking the modular organization of motor behavior. Therefore, to enhance comprehension of muscle coordination dynamics during multi-joint movements in chronic ankle instability (CAI), exploring muscle synergies during landing in CAI patients is imperative.

New Insights Optimize Landing Strategies to Reduce Lower Limb Injury Risk.

Single-leg landing (SL) is often associated with a high injury risk, especially anterior cruciate ligament (ACL) injuries and lateral ankle sprain. This work investigates the relationship between ankle motion patterns (ankle initial contact angle [AICA] and ankle range of motion [AROM]) and the lower limb injury risk during SL, and proposes an optimized landing strategy that can reduce the injury risk. To more realistically revert and simulate the ACL injury mechanics, we developed a knee musculoskeletal model that reverts the ACL ligament to a nonlinear short-term viscoelastic mechanical mechanism (strain rate-dependent) generated by the dense connective tissue as a function of strain.

Exploring biomechanical variations in ankle joint injuries among Latin dancers with different stance patterns: utilizing OpenSim musculoskeletal models.

Dancers represent the primary demographic affected by ankle joint injuries. In certain movements, some Latin dancers prefer landing on the Forefoot (FT), while others prefer landing on the Entire foot (ET). Different stance patterns can have varying impacts on dancers' risk of ankle joint injuries.

Finite Element Analysis of Head-Neck Kinematics in Rear-End Impact Conditions with Headrest.

A detailed three-dimensional (3D) head-neck (C0-C7) finite element (FE) model was developed and used to dictate the motions of each cervical spinal segment under static physiological loadings of flexion and extension with a magnitude of 1.0 Nm and rear-end impacts. In this dynamic study, a rear-end impact pulse was applied to C7 to create accelerations of 4.

The Effect of Concave-Side Intertransverse Ligament Laxity on the Stress of AIS Lumbar Spine Based on Finite Element Method.

(1) Background: Scoliosis has the mechanical characteristic of asymmetric stress distribution, which is one of the reasons for the aggravation of scoliosis. Bracing therapy is the best treatment for AIS, but it is difficult and costly to operate. Is it possible to reduce pressure in the concave side by relaxing the ITL in the concave side of scoliosis, so as to improve the abnormal stress distribution of scoliosis? In this paper, a finite element method was used to simulate the effect of the relaxation of concave-side ITL on the stress of a lumbar spine with scoliosis, which provides some guidance for the treatment of scoliosis.

Intracellular Oxidative Stress Induced by Physical Exercise in Adults: Systematic Review and Meta-Analysis.

A physical exercise program is one of the commonly used methods for improving an individual's antioxidative capacity. However, an inappropriate physical exercise program would induce extra oxidative stress (OS), and the relationship between the details of a physical exercise protocol and the severity of intracellular OS is still unclear. A systematic review and meta-analysis of randomized controlled trials were conducted by searching PubMed, Medline, and Web of Science with the eligibility criteria: (1) participants over 18 years old; (2) physical exercise interventions; (3) 8-hydroxydeoxyguanosine, F2-isoprostanes, and protein carbonyls (PCs) as outcome measures; (4) published in English and peer-reviewed.

Analysis of stress and stabilization in adolescent with osteoporotic idiopathic scoliosis: finite element method.

To explore the effect of osteoporosis on the stress, stability, and lumbar intervertebral disc of AIS lumbar vertebrae by finite element method. Better understand the biomechanical characteristics of osteoporotic scoliosis. Based on the CT images of normal lumbar vertebrae and lumbar vertebrae with AIS, the finite element models were established to simulate the estimated osteoporosis by changing the Young's modulus of cortical bone, cancellous bone, and endplate.

Effect of Long-Distance Running on Inter-segment Foot Kinematics and Ground Reaction Forces: A Preliminary Study.

Long-distance running has gained massive popularity in recent years, yet the intra-foot adaptations during this event remain unclear. This study aimed to examine the kinematic and ground reaction force alterations induced within the foot following a 5 and 10 km run using the Oxford Foot Model Ten marathon-experienced recreational runners participated in this study. Five-kilometer running led to more rearfoot dorsiflexion, rearfoot eversion, and rearfoot rotation while less forefoot plantarflexion during the stance phase.

A Mixed Comparisons of Aerobic Training With Different Volumes and Intensities of Physical Exercise in Patients With Hypertension: A Systematic Review and Network Meta-Analysis.

It is essential for patients with hypertension to effectively reduce and maintain appropriate blood pressure levels. As one of the non-pharmacological and invasive methods, physical exercise seems to improve blood pressure of the patients with hypertension. However, different volumes and intensities of physical exercise on the improvement of hypertension are different.

Effect of Displacement Degree of Distal Chevron Osteotomy on Metatarsal Stress: A Finite Element Method.

The stress of foot bone can effectively evaluate the functional damage caused by foot deformity and the results of operation. In this study, the finite element method was used to investigate the degree of displacement of distal chevron osteotomy on metatarsal stress and metatarsophalangeal joint load; Methods: Four finite element models of displacement were established by using the CT images of a patient with moderate hallux valgus (hallux valgus angle and intermetatarsal angle were 26.74° and 14.

The Influence of Heel Height on Strain Variation of Plantar Fascia During High Heel Shoes Walking-Combined Musculoskeletal Modeling and Finite Element Analysis.

The therapeutic benefit of high heel shoes (HHS) for plantar fasciitis treatment is controversial. It has been suggested that plantar fascia strain can be decreased by heel elevation of shoes which helps in body weight redistribution throughout the length of the foot. Yet it is a fact that the repetitive tension caused by HHS wearing resulting in plantar fasciitis is a high-risk disease in HHS individuals who suffer heel and plantar pain.

A Simulation Analysis of Maternal Pelvic Floor Muscle.

Pelvic floor disorder (PFD) is a common disease affecting the quality of life of middle-aged and elderly women. Pelvic floor muscle (PFM) damage is related to delivery mode, fetal size, and parity. Spontaneous vaginal delivery causes especially great damage to PFM.

Finite element analysis of the lumbar spine in adolescent idiopathic scoliosis subjected to different loads.

To explore the biomechanical changes of the lumbar spine segment of idiopathic scoliosis under different loads by simulating six kinds of lumbar spine motions based on a three-dimensional finite element (FE) model. Methods According to the plain CT scan data of L1-L5 segment of an AIS patient, a three-dimensional FE model was established to simulate the biomechanics of lumbar scoliosis under different loads. The lumbar model was reconstructed using Mimics20.

Current Evidence on Traditional Chinese Exercise for Cancers: A Systematic Review of Randomized Controlled Trials.

Traditional Chinese exercise (TCE) has gradually become one of the widespread complementary therapies for treatment and recovery of cancers. However, evidence based on the systematic evaluation of its efficacy is lacking, and there appears to be no conclusion regarding the setting of TCE interventions. The purpose of this systematic review is to summarize the current randomized controlled trials (RCTs) that outline the effects of TCE on cancer patients.

Finite element study of the mechanical response in spinal cord during the thoracolumbar burst fracture.

Background: The mechanical response of the spinal cord during burst fracture was seldom quantitatively addressed and only few studies look into the internal strain of the white and grey matters within the spinal cord during thoracolumbar burst fracture (TLBF). The aim of the study is to investigate the mechanical response of the spinal cord during TLBF and correlate the percent canal compromise (PCC) with the strain in the spinal cord.

Methodology/principal Findings: A three-dimensional (3D) finite element (FE) model of human T12-L1 spinal cord with visco-elastic property was generated based on the transverse sections images of spinal cord, and the model was validated against published literatures under static uniaxial tension and compression.

Finite element study on the amount of injection cement during the pedicle screw augmentation.

Study Design: A finite element analysis of the screw pullout procedure for the osteoporotic cancellous bone using screw-bone unit model without cortical layer.

Objective: The objective is to determine the region of effect (RoE) during the screw pullout procedure and predict the proper amount of injection cement (AIC) in screw augmentation.

Summary Of Background Data: For the osteoporotic spine, the AIC is a critical factor for the augmentation screw performance and leakage risk.

Finite element modeling of a 3D coupled foot-boot model.

Increasingly, musculoskeletal models of the human body are used as powerful tools to study biological structures. The lower limb, and in particular the foot, is of interest because it is the primary physical interaction between the body and the environment during locomotion. The goal of this paper is to adopt the finite element (FE) modeling and analysis approaches to create a state-of-the-art 3D coupled foot-boot model for future studies on biomechanical investigation of stress injury mechanism, foot wear design and parachute landing fall simulation.

Relationship between architectural parameters and sample volume of human cancellous bone in micro-CT scanning.

Truly representative architectural parameters of trabeculea can be extremely difficult to achieve based on scanning images because of variable porosity and distribution of trabeculae within the specific overall scanned volume of bone. Accordingly, in present study different selective volume of interests, measured from centroid of μ-CT scanned human vertebral body, were analyzed to determine the architectural parameters (BV/TV, BS/BV, Tb.Th, Tb.

Influence prediction of tissue injury on frequency variations of the lumbar spine under vibration.

A three-dimensional finite element model of the spine T12-S1 segment was developed and used to investigate biodynamics characteristics of the human lumbar spine. The T12-S1 model was carefully built including spinal vertebrae, intervertebral discs, and ligaments so as to approach the real human spine. Finite element modal analysis was carried out to obtain vibration modes and resonant frequencies of the spine.

Vibration modes of injured spine at resonant frequencies under vertical vibration.

Study Design: A detailed three-dimensional finite element model of the spine segment T12-Pelvis was developed to investigate dynamic characteristics of whole lumbar spine with injured cases.

Objective: This study investigates the motion mechanism of the human lumbar spine and the effect of component injuries on adjacent spinal components under whole body vibration.

Summary Of Background Data: Several investigations have analyzed the influence of injured spines on adjacent spinal components under static loadings.