Background It remains unclear how the head and stem diameters for the radial head prosthesis could affect mechanical properties of the lateral collateral ligament measured by strain changes during elbow and forearm motions. Methods Eight cadaveric specimens were secured to the device, which allows elbow flexion-extension and forearm pro-supination. Using six different implant combinations comprising

Background In understanding the onset factors associated with Plantar heel pain and the structure of heel fat pad, measuring its thickness is the most basic frequently reported evaluation. This study aimed to determine changes to heel fat pad thickness associated with age and gender and the relationship between heel fat pad thickness, age, and physique in Japanese. Methods This study was carried out

Background Ellipticals are used to address walking and cardiorespiratory training goals of older adults, some of whom are at risk for foot injuries. Variations in joint kinematics and muscle demands when using different ellipticals could lead to plantar pressure differences. This study explored plantar pressure variables during gait and use of four ellipticals. Methods Plantar pressures were recorded

Background The handrail is an effective means of assisting sit-to-stand movements. As some elderly people need force to support their body during sit-to-stand movements because of instability and weakness; however, few handrails are specifically shaped to generate more force and support the body. This study aimed to investigate the effect of a newly designed curved-angled handrail on the reaction force

Background Running with prostheses has become a common activity for amputees participating in sports and recreation. However, very few studies have characterized the kinematic and kinetic parameters of walking in individuals with amputation who are runners. Thus, this study attempts to elucidate the kinematics and kinetics of walking in runners with a unilateral transfemoral amputation or knee-disarticulation

Background Generating a force at the hand requires moments about multiple joints by a theoretically infinite number of arm and shoulder muscle force combinations. This allows for learning and adaptation and can possibly be captured using the complexity (entropy) of an isometrically generated force curve. Patients with Subacromial Pain Syndrome have difficulty to explore alternative, pain-avoiding,

Background Prosthetic feet are available in a range of stiffness categories, however, there is limited evidence to guide optimal selection during prosthetic foot prescription. The aim of this study was to determine the effect of commercial prosthetic foot stiffness category on foot-ankle biomechanics, gait symmetry, community ambulation, and relative foot stiffness perception. Methods Participants

Background Panda Rope Bridge Technique (PRBT) was an new minimally invasive technique consisted of two bridge anchors (proximal anchors at calcaneus and distal anchors at myotendinous junction) and strong ropes (threads of the suture anchors) stretched between them, which was suitable for early accelerated rehabilitation of Achilles tendon rupture. However, the optimal knot configuration with PRBT

Background. Maintaining balance in response to perturbations during walking often requires the use of corrective responses to keep the center of mass within the base of support. The relationship between center of mass and base of support is often quantified using the margin of stability. Although people post-stroke increase the margin of stability following perturbations, control deficits may lead

Background Hop tests are commonly used in clinical environments to measure function after sport-related knee injuries. Joint angle measurement during hopping is feasible in research-based environments equipped with motion-capture systems. Employing these systems in clinical research settings is inefficient, given the associated cost, preparation time, and expertise required to administer and interpret

Background Gait is negatively affected with increasing age. It is widely accepted that training produces physical-functional improvements in older adults, which can be assessed with numerous physical-functional tests. However, very few studies have been carried out using accelerometry to analyse the training effect on kinetic and kinematic variables in older adults, and there is no one that investigate

Background Overground lower-limb robotic exoskeletons are assistive devices used to facilitate ambulation and gait rehabilitation. Our understanding of how closely they resemble comfortable and slow walking is limited. This information is important to maximise the effects of gait rehabilitation. The aim was to compare the 3D gait parameters of able-bodied individuals walking with and without an exoskeleton

Background Cranial pia mater, the innermost layer of the meninges, protects the central nervous system by tightly wrapping the brain and damping the external impact force to the brain. Accurate experimental data of the mechanical property of the cranial pia mater can enhance the theoretical prediction of traumatic brain injury or the scientific surgery design for brain disease. The aim of this study

Background Traditional testing to identify asymmetries after anterior cruciate ligament reconstruction include four similar horizontal hopping tests. The purpose of this study was to determine whether a single-leg vertical hopping test can identify performance and biomechanical asymmetries, and whether performance asymmetries provide unique information compared to traditional tests. Methods Twelve

Background Grab bars are a common fall prevention strategy in the bathroom, but biomechanical data are lacking to support clinicians' interventions. This study aims to determine the magnitude and duration of the force applied to four grab bar configurations during complete bathtub transfers on a potentially slippery surface. Methods A three factorial repeated measures design was used in an experimental

Background Osteoporosis is associated with the risk of fractures near the hip. Age and comorbidities increase the perioperative risk. Due to the ageing population, fracture of the proximal femur also proves to be a socio-economic problem. Preventive surgical measures have hardly been used so far. Methods 10 pairs of human femora from fresh cadavers were divided into control and low-volume femoroplasty

Background It has been dogma that handedness greatly impacts daily activities. Interruptions in the ability to utilize the dominant arm due to neuromusculoskeletal injuries could negatively impact performance of activities of daily living. Daily activity can be measured using activity monitors. This study aimed to examine how arm dominance impacts function by immobilizing the arms of healthy individuals

Background The underlying mechanism of pulsatile flushing technique has not been fully elucidated, and the partial understanding of the mechanism has been confined to hydrodynamic simulation, ignoring the dynamic interaction among the catheter, blood vessel, blood stream, and saline. Methods The peripheral intravenous catheter and vein models and their internal flow fields were assessed using a commercial

Background The current literature indicates that functional capacity is associated with physical performance and body composition measurements in older adults. However, it is not clear which tests can best explain the functional capacity in this population. This study aimed to investigate the physical performance and body composition determinants of functional capacity in older adults. Method Twenty-four

Background Frequent falls while walking among individuals with incomplete spinal cord injury may suggest impairments in reactive balance control; however, reactive balance control during walking has not been studied in this population. The objective was to compare reactive balance control with respect to changes in margin of stability, onset of arm and heel responses, and onset and magnitude of muscle

Background Duchenne muscular dystrophy is an X-linked muscle disease caused by dystrophin absence. Muscle weakness is a major determinant of the gait impairments in patients with Duchenne muscular dystrophy and it affects lower limbs more often than upper limbs. Monitoring progression of motor symptoms is key to plan treatments for prolonging ambulation. Methods The progression of gait impairment in

Background Movement asymmetries between lower limbs are commonly exhibited by adults after transtibial amputation. However, the degree of movement asymmetry between low- and high-demand functional tasks remains unknown. Methods Kinematic and kinetic data were collected during overground walking (low-demand) and step ascent (high-demand) tasks for two groups: 1) persons with transtibial amputation and

Background Management of proximal humerus fractures is challenging, especially in elderly. Locking plating is a common surgical treatment option. The Proximal Humerus Internal Locking System (plate-A) has shown to lower complication rates compared to conventional plates, but is associated with impingement risk, which could be avoided using Peri-articular Proximal Humerus Plate (plate-B). Nevertheless

Background Persons with multiple sclerosis are often at higher risk for falling, but clinical disability scales and fall risk questionnaires are subjective and don't provide specific feedback about why an individual is unstable. The purpose of this study was to determine how relationships between trunk and foot acceleration variability relate to physiological impairments, clinical disability scales

Background The heel is one of the most common sites of pressure ulcers and the anatomical location with the highest prevalence of deep tissue injury. Several finite element modeling studies investigate heel ulcers for bedridden patients. In the current study we have added the implementation of the calf structure to the current heel models. We tested the effect of foot posture, mattress stiffness, and

Background The aim of this study was to use ultrasound vibro-elastography (UVE) for measuring surface wave speed and assessing mechanical properties of ex vivo porcine reproductive tissues, including the uterus, bladder, cornua and cervix. Methods In UVE, a 0.1-s harmonic vibration at low frequency was generated on the tissue surface with a handheld shaker. A linear-array ultrasound probe was used

Background Residual limb volume loss is a source of prosthetic socket fit problems in people with lower-limb amputation. The aim of this study was to investigate a novel volume recovery strategy for people with trans-tibial amputation. Methods Test sockets for people with trans-tibial amputation were created that allowed panels of an adjustable socket and the underlying elastomeric liner to be pulled

Background The TomoFix plate has been extensively used in high tibial osteotomy surgery to stabilize the distracted tibial bones. However, distal pain related to plate irritation was considered one of the most relevant complications for this fixation device. This study aimed to correlate reports of distal pain with the profiles of the distracted tibia and initial plate and plate contour. Methods This

Background The aim of the study was to compare the bone mineral density changes between unmatched patients undergoing total hip arthroplasty receiving uncemented and cemented type of implants. Previous studies have used DEXA or a two dimensional analysis to estimate the bone quality following total joint replacement, whereas this study presents the changes in three dimensions. Methods Fifty subjects

Background Conditions requiring cervical decompression and stabilization are commonly treated using anterior cervical discectomy and fusion using an anterior cage-plate construct. Anterior zero profile integrated cages are an alternative to a cage-plate construct, but literature suggests they may result in less motion reduction. Interfacet cages may improve integrated cage stability. This study evaluated

Background Mechanical stimulation of joints regulates the biosynthetic activity of chondrocytes. It has been argued that excessive loading might cause chondrocyte death, leading to degeneration of cartilage and cause osteoarthritis. The aims of this study were to apply a high, short-term loading, and a low intensity, long-term loading protocol to intact joints in life animals and determine changes

Background Numerous studies have reported an association between rotator cuff injury and two-dimensional measures of scapular morphology. However, the mechanical underpinnings explaining how these shape features affect glenohumeral joint function and lead to injury are poorly understood. We hypothesized that three-dimensional features of scapular morphology differentiate asymptomatic shoulders from

Background Little is known about the relationship between vertical ground reaction force (vGRF) and muscle strength while climbing stairs after total hip arthroplasty (THA). Methods We investigated the relationship between muscle strength and vGRF during stair climbing in 21 women with THA. Differences in the time required to climb stairs and side-to-side differences in muscle strength and vGRF during

Background Neuromuscular disorders e.g. spinal muscular atrophy and stroke have a negative impact on functional movement capability. These disorders affect lower and upper motor neurons respectively. Methods In this study high spatial resolution electromyography was used to record the motor unit activity in 3 groups: healthy subjects, a spinal muscular atrophy group and a stroke group. 7 clinically

Background One of most accepted principles for treating Kienböck's disease before wrist degeneration settles in is to decompress the lunate by an osteotomy. Several osteotomies have been proposed since 1935. However, they are based on biomechanical hypotheses that are sometimes conflicting: This study compares the decompression effect of radius transverse shortening, radius lateral closing and medial

Background Trial fitting of the acetabular component in uncemented total hip replacement is traditionally done by trial cups. Since trial cups do not resemble the real press-fit obtained by the definitive cup, a dynamic trial inserter, called the X-pander ®, was developed to mimic the real amount of press-fit. However, the concern is raised of losing the initial press-fit by using the X-pander® due

Background Reduced coronary flow reserve in aortic stenosis and after transcatheter aortic valve implantation is usually attributed to physiological factors taking place during systole, such as an increase in coronary resistance, and backward waves intensity. In this paper, we suggest an additional factor related to the diastolic hemodynamics in the aortic root. Methods We measured left ventricle,

Background Simultaneous dislocation of the proximal and distal radio-ulnar joints without bony injuries has been reported, but the mechanism remains unclear. We investigated concurrent proximal and distal radio-ulnar joint instability after sequential sectioning of the annular ligament, triangular fibrocartilage complex, and quadrate ligament. Methods We performed this biomechanical study with six

Background Non-degradable resurfacing implants are being developed for treatment of focal cartilage defects. Performance of these implants has been investigated opposing intact cartilage. This study investigates whether implants would perform equally well when the opposing cartilage is fibrillated. Methods Human osteochondral strips (~2x1x1 cm) with a smooth (n = 9) or fibrillated (n = 17) cartilage

Background Medial patellofemoral ligament reconstruction becomes first-choice surgical procedure for patients with a history of lateral patellar dislocations but there is limited knowledge about neuromuscular activation patterns of individuals with a history of patellar dislocation who underwent medial patellofemoral ligament reconstruction. Objective The aim of this study was to compare muscle activation

Background Ventral hernia repair needs to be improved since recurrence, postoperative pain and other complications are still reported in many patients. The behavior of implants in vivo is not sufficiently understood to design a surgical mesh mechanically compatible with the human abdominal wall. Methods This analysis was based on radiological pictures of patients who underwent laparoscopic ventral

Background To verify the effect of dual-task on postural oscillation during sit-to-stand movement in children with Cerebral Palsy. Methods 17 children with spastic unilateral cerebral palsy and 20 typically-developing children, aged 5 to 12 years, performed the following tasks: Simple task: sit-to-stand with arms crossed against the chest; bimanual dual-task: sit-to-stand while carrying a tray; unimanual

Background Expandable titanium implants have proven their suitability as vertebral body replacement device in several clinical and biomechanical studies. Potential stabilizing features of personalized 3D printed titanium devices, however, have never been explored. This in vitro study aimed to prove their equivalence regarding primary stability and three-dimensional motion behavior in the mid-thoracic

Background The purpose of this study was to evaluate the effect of low-frequency self-administered vibration therapy into myofascial trigger points in the upper trapezius and levator scapulae on patients with chronic non-specific neck pain. Methods Twenty-eight patients with chronic non-specific neck pain were randomly assigned into a vibration group, receiving 10 self-applied sessions of vibration

Background The Trendelenburg test has been used to assess hip abductor muscle function. A standardized evaluation of the test requires an assessment of both pelvis and trunk coronal plane alignment as the patient stands on one leg for 30 s. Coronal plane biomechanics using motion analysis allows for development of objective criteria to grade the test response. The aim of this study was to develop biomechanical

Background Total Knee Replacement surgery restores joint function in patients with advanced osteoarthritis. There are several prostheses available based on different mechanisms, which guarantee knee stability during Activities of Daily Living. The aim of this study is to compare ball-in-socket (or Medial Pivot) and post-cam mechanisms to detect possible differences in terms of biomechanical parameters

Background Stochastic resonance vibrations are known to enhance balance in the elderly and patients with impaired plantar sensation. However, the underlying mechanisms of plantar vibrations on balance capacity are not well resolved. This study investigated the impact of stochastic resonance vibrations on activities of major extrinsic foot muscles and center of pressure sway in tactile inhibited subjects

Background Woodcast® is a wood-plastic composite casting material that becomes pliable and self-adhesive when heated to 65 °C and returns to being weightbearing as it cools down. The present study aims to test whether this novel non-toxic casting material is strong enough for clinical use by comparing its strength against materials that are already used in weightbearing casting applications such as

Background Diabetes can cause biomechanical alterations that may be responsible for additional changes to those existing in a regular gestational period. The way a maternal body responds when affected by diabetes has not been clearly understood. This study aimed to describe the influence of type 1 diabetes on pregnant women's postural control. Methods Forty pregnant women in their third gestational

Background Newer repair techniques of anterior cruciate ligament tears, including augmentation with internal brace, have shown promising clinical results. Few biomechanical studies exist comparing anterior cruciate ligament repair only versus repair with internal brace. The purpose of this study was to compare the load to failure and stiffness of anterior cruciate ligament repair with internal brace

Background The tissue stress theory is commonly used to prescribe foot orthoses, however the mechanisms of foot orthoses are not understood well. The effect foot orthotics have on the plantar intrinsic muscles remains unclear. The study was designed to assess changes in muscle size and activity of the intrinsic muscles of individuals with pes planus after wearing custom-made foot orthotics for 12-weeks

Background Lag screw osteosynthesis in odontoid fractures shows a high rate of pseudarthrosis. Biomechanical properties may play a role with insufficient fragment compression or unnoticed screw stripping. A biomechanical comparison of different constructed lag-screws was carried out and the biomechanical properties determined. Methods Two identical compression screws with different pilot holes (1.25

Background Elevated patellofemoral joint forces appear to contribute to the development of patellofemoral pain. As a result, treatment of patellofemoral pain often includes movement retraining intended to reduce patellofemoral joint forces. Real-time visual feedback has been shown to be effective for retraining running kinematics; however, we are not aware of a previous study that has examined the

Backgrounds The correlation between in vivo knee kinematics and alignment has not been fully elucidated. Recently, similar or better clinical outcomes have been reported by restoration of mild varus alignment after total knee arthroplasty for preoperative varus knees. The aim of this study was to evaluate the effect of postoperative alignment on knee kinematics during a deep knee bend activity. Methods

Background The purpose of this study was to analyze sagittal-plane knee biomechanics in individuals with ACL reconstructions in bilateral countermovement jumps. This aimed to determine potential knee compensation strategies during a high-demanding symmetrical movement task from pre to six months post-ACL reconstruction. Methods 20 ACL-reconstructed individuals were tested pre-operatively, and then

BACKGROUND Long-term survival of hip implants is of increasing relevance due to the rising life expectancy. The biomechanical effect of strain shielding as a result of implant insertion may lead to bone resorption, thus increasing risk for implant loosening and periprosthetic fractures. Patient-specific quantification of strain shielding could assist orthopedic surgeons in choosing the biomechanically

BACKGROUND Most laboratory studies investigating scapholunate dissociations are based on normal cadaver arms with serially sectioned ligaments. It is assumed that the kinetic behavior of a ligament-sectioned wrist is similar to a scapholunate dissociation. We tested five cadaver wrists with real injuries. The goal of this research was to evaluate the biomechanical behavior of scapholunate advanced

BACKGROUND Multiple drug resistance of a growing number of bacterial pathogens represents an increasing challenge in conventional curative treatments of infectious diseases. However, the development and testing of new antibiotics is associated with a high number of animal experiments. METHODS A symmetrical parametrized lung test rig allowing the exposure of air-passage surfaces to antibiotics was designed

BACKGROUND Anecdotally, children with Autism Spectrum Disorder have highly variable lower extremity walking patterns, yet, this has not been sufficiently quantified. As such, the purpose of this study was to examine walking pattern variability by way of lower extremity coordination and spatio-temporal characteristics in children with autism compared with individuals with typical development during

BACKGROUND Femoroacetabular impingement is a patho-mechanical hip condition that can lead to restrictions in hip motion, particularly in end-range hip flexion, adduction and/or internal rotation. Radiographic evidence of femoroacetabular impingement - cam and/or pincer morphology - is prevalent in the general and athletic populations. There is, however, a lack of studies that have analyzed the performance