Background: Carpal tunnel syndrome is the most common focal mono-neuropathy. A study was designed to compare the effects of traditional open carpal tunnel release with median neurolysis and Z-plasty reconstruction of the transverse carpal ligament on post-operative hand pain and hand function in patients with idiopathic carpal tunnel syndrome.   Methods: Fifty-two patients with idiopathi...

Abstract: Cracks in solids can be detected by ultrasound if they are open. However, their detection is not easy when they are closed with a closure stress, and it is a fundamental problem in ultrasonic testing. Subharmonics with half the input frequency is potentially useful in the detection and evaluation of such cracks. We developed analytical and numerical theories accounting for the crack p...

Introduction: The fracture mechanisms of bone tissue have been described as a damage accumulation process, which starts with the initiation and propagation of microcracks. Knowledge of crack initiation and propagation at tissue level (tissue fracture toughness) is critical to understand and prevent bone fractures. Tissue fracture toughness could provide valuable information for defining bone qu...

Experimental injuries of cartilage and bone were produced by applying shear force to the articular surfaces of the lateral femoral condyles of six-month-old pigs under various loading conditions. The lesions were divided into two groups, 'open' or 'closed', depending on the presence of a crack on the articular surface. Each was further divided into four types according to the depth of penetrati...

the cracked brazilian disc (cbd) specimen is widely used in order to determine mode-i/ii and mixed-mode fracture toughness of a rock medium. in this study, the stress intensity factor (sif) on the crack-tip in this specimen is calculated for various geometrical crack conditions using the extended-finite element method (x-fem). this method is based upon the finite element method (fem). in this m...

Purpose: In the present paper a crack arrest model is proposed for an infinitely long narrow poled piezoelectric strip embedded with a centrally situated finite hairline straight crack. Design/methodology/approach: The ceramic of the strip is assumed to be mechanically brittle and electrically ductile. Combined mechanical and electrical loads applied at the edge of the strip open the rims of th...

A method of analysis for determining crack propagation loads on wood beams with end splits is presented. The method is based on (1) linear elastic orthotropic fracture mechanics concepts, (2) theory of complex variables, and (3) least squares boundary value collocation (BVC). Using this method, the critical stress intensity factor, Kllc of Douglas-fir beams with end splits is determined to be 2...

A transition from surface-roughening collapse to a random network collapse has been investigated in fatty acid Langmuir monolayers. In contrast to the random network crack pattern, the surface-roughening crack pattern grows on a much longer time scale and on a much shorter length scale. A change in the isotherm from a surface pressure "spike" to a "plateau" occurs at the transition. In the surf...

Consider the scattering of an electromagnetic time-harmonic plane wave by an infinite cylinder having an open crack Γ and a bounded domain D in R2 as cross section. We assume that the crack Γ is divided into two parts, and one of the two parts is possibly coated on one side by a material with surface impedance λ. Different boundary conditions are given on Γ and ∂D. Applying potential theory, th...

This paper reviews some of the advances that have been made in stress analyses of cracked aircraft components, in the understanding of the fatigue and fatigue-crack growth process, and in the prediction of residual strength of complex aircraft structures with widespread fatigue damage. Finite-element analyses of cracked structures are now used to determine accurate stress-intensity factors for ...