Search results for " Joints"

Mechanical behaviour of SPR/co-cured composite to aluminium joints

2012

Moving multi-loads problem in layered cracked beams with interlayer slip

2017

This contribution concerns the vibration response of layered cracked uniform beams with interlayer slip under moving multiple loads. Considering a linear constitutive relation between the horizontal slip and the interlaminar shear force, the Euler-Bernoulli hypothesis is assumed to hold for each layer separately. Modeling cracks as internal elastic rotational joints, related discontinuities of the response variables are treated by the theory of generalized functions. In this manner, exact eigenfunctions are derived from a characteristic equation built as determinant of 6x6 matrix, for any number of cracks. Building pertinent orthogonality conditions for the deflection eigenfunctions, the re…

Fatigue Design of Cruciform Joints including V-notch Effect at the Weld Toe

2014

Abstract The present paper proposes a new and more accurate fatigue life prediction model for fillet welded joints in steel subjected to constant amplitude loading. With the traditional fracture mechanics approach, the greatest difficulty when computing the fatigue life of a welded detail is to determine the initial crack size a0. The classical way to determine the stress intensity factor K (SIF) is by using the following formula Where σ is the applied stress, a is the crack size and g(a/T) the geometrical correction factor which has been determined by Gurney function or similar solutions. This approach is not accurate for short crack because of the singular V-notch behaviour close to the c…

The synovial joints of the human foot.

2007

The human foot is considered an organ with an assortment of tissues with different morphological characteristics and well defined limits, but effectively has a simple functionality when static that becomes extremely complex when in movement. Its complex structure, comprised of an elastic and resistant skin covering a bone framework, joints, muscles, tendons, veins and nerves, can be compared to an efficient mechanical assembly. After a long and extraordinary evolutive journey, the human foot has undergone numerous changes to perfect its function; it has lost most of its grabbing function whilst gaining new characteristics that have ultimately allowed the modern man to stand upright. The com…

Balance training versus balance training and foot and ankle mobilization: a pilot randomized trial in community-dwelling older adults

2019

Background: Balance limitations and foot and ankle problems are common in older adults. Objective: To determine the impact of augmented balance training with foot and ankle mobilizations (FAMs) on ...

Periosteal repair of the dorsal calcaneocuboid ligament: a comparative biomechanical study.

2007

Background: Isolated lateral calcaneocuboid joint instability rarely is described. Missed or delayed diagnosis resulting in inadequate treatment may lead to chronic instability, followed by sports inability and handicap in daily life. Besides arthrodesis, anatomic repair augmenting the elongated dorsal calcaneocuboid ligament with a local periosteal flap has recently been described for treatment. Methods: In a controlled laboratory study, eight isolated fresh-frozen human cadaver calcaneocuboid specimens were strained in a varus direction until failure of the dorsal calcaneocuboid ligaments. Then the dorsal calcaneocuboid ligaments were reconstructed with free periosteal flaps and tensile …

Acute effects of wearing compression knee-length socks on ankle joint position sense in community-dwelling older adults

2021

Functional proprioceptive information is required to allow an individual to interact with the environment effectively for everyday activities such as locomotion and object manipulation. Specifically, research suggests that application of compression garments could improve proprioceptive regulation of action by enhancing sensorimotor system noise in individuals of different ages and capacities. However, limited research has been conducted with samples of elderly people thus far. This study aimed to examine acute effects of wearing knee-length socks (KLS) of various compression levels on ankle joint position sense in community-dwelling, older adults. A total of 26 participants (12 male and 14…

An easy and safe training method for trunk function improves mobility in total knee arthroplasty patients: A quasi-randomized controlled trial

2018

Objective Total knee arthroplasty (TKA) is aimed mainly at reducing pain and restoring mobility. However, mobility deficits can persist even longer than 1 year. The trunk function and movement velocity of any region have been recently recognized to be critical for determining mobility in older people. Therefore, the main goal of this quasi-randomized trial is to clarify the effectiveness of a novel training method, the seated side tapping (SST) training, for improving mobility by focusing on movement velocity of trunk function in the short term after TKA. Methods SST training consists of side trunk movements repeated as quickly as possible in a seated position. All participants after TKA we…

The Inactivation Principle: Mathematical Solutions Minimizing the Absolute Work and Biological Implications for the Planning of Arm Movements

2008

An important question in the literature focusing on motor control is to determine which laws drive biological limb movements. This question has prompted numerous investigations analyzing arm movements in both humans and monkeys. Many theories assume that among all possible movements the one actually performed satisfies an optimality criterion. In the framework of optimal control theory, a first approach is to choose a cost function and test whether the proposed model fits with experimental data. A second approach (generally considered as the more difficult) is to infer the cost function from behavioral data. The cost proposed here includes a term called the absolute work of forces, reflecti…

Medial buttressing of the quadrilateral surface in acetabular and periprosthetic acetabular fractures

2020

Background In geriatric acetabular fractures, the quadrilateral plate is often involved in the fracture pattern and medially displaced. Open reduction and internal fixation (ORIF) includes reduction of the quadrilateral plate and securing its position. In this study, the concept of medial buttressing in acute and periprosthetic acetabular fractures is evaluated. Materials and methods Patients, who sustained an acetabular fracture between 2012 and 2018, in whom ORIF with a specific implant for medial buttressing was performed, were included in the study. Patients were divided in two groups; acute acetabular fractures (group 1) and periprosthetic acetabular fractures (group 2). Demographics,…