The aims of the present work were: to calculate lifting energy consumption (LEC) in work activities designed to have a growing lifting index (LI) by means of revised NIOSH lifting equation; to evaluate the relationship between LEC and forces at the L5-S1 joint. The kinematic and kinetic data of 20 workers were recorded during the execution of lifting tasks in three conditions. We computed kinet...

BACKGROUND Reverse total shoulder arthroplasty (RTSA) is widely used; however, the effects of RTSA geometric parameters on joint and muscle loading, which strongly influence implant survivorship and long-term function, are not well understood. By investigating these parameters, it should be possible to objectively optimize RTSA design and implantation technique. QUESTIONS/PURPOSES The purpose...

Mechanisms of femoral fracture of the condyles and shaft were experimentally investigated through controlled knee impact ofdenuded femurs in six human cadavers. High-speed movies recorded knee joint compression, femoral displacements and deformation, and fracture initiation. Fracture initiated at 10.6 + 2.7 kN knee load after 1.3 + 0.1 cm ofknec joint compression for a 10.1 kg rigid impact at 1...

BACKGROUND Triple-threaded, cannulated headless screws of varying thread diameters and pitch are designed to maintain thread length across the arthrodesis plane, provide joint compression, and reduce countersinking. This study tested the biomechanical fixation strength of conventional partially threaded lag screws compared to triple-threaded headless screws in first metatarsophalangeal joint ar...

Damage and degeneration of articular joints is a major healthcare concern, due to the association of joint disease with ageing, the current strong demographic changes in the proportion of elderly in the population, and the increased incidence of trauma in a sports-active younger population. These joints are biomechanical organs that transmit load between bones in our skeleton, and the articular...

BACKGROUND The effect of osteoallograft repair of a Hill-Sachs lesion and the effect of allograft fit on glenohumeral translations in response to applied force are poorly understood. PURPOSE To compare the impact of a 25% Hill-Sachs lesion, a perfect osteoallograft repair (PAR) of a 25% Hill-Sachs lesion, and an "imperfect" osteoallograft repair (IAR) of a 25% Hill-Sachs lesion on glenohumera...

Electrical load modeling and forecasting are critically important in the electrical network and smart grid. The sparse Bayesian Learning (SBL) algorithm can be utilized to model and forecast the electrical load behavior. The SBL algorithm can solve a sparse weight vector with respect to a kernel matrix for modeling electricity consumption. However, traditional SBL can only handle an electricity...

Runners do not have a greater prevalence of knee osteoarthritis (OA) than nonrunners. The hypothesis that joint loads in running do not cause OA is forwarded. Two mechanisms are proposed: 1) cumulative load, which is surprisingly low in running, is more important for OA risk than peak load, and 2) running conditions cartilage to withstand the mechanical stresses of running.

The menisci are two semilunar-shaped fibrocartilagenous structures, which are interposed between the femoral condyles and tibial plateaux. They have an important role in knee function. Long-term follow-up studies showed that virtually all meniscectomized knees develop arthritic changes with time. The meniscus has functions in load bearing, load transmission, shock absorption, joint stability, j...

Three-dimensional finite element models are developed to investigate the effects of both tensile load and uniform temperature load on the stresses in hybrid joints. During the solution of the problem, finite element method (FEM) is preferred, as this method is very suitable for solving many engineering problems. An aluminum sheet is bonded a composite sheet. Hybrid joints are designed from both...