Siemens Virtual Wedge factor may drift significantly due to increase in output as dose rate decreases. This variation of output is caused by defective sample and hold boards in the dosimetry circuit due to radiation damage. In this note, we present a simple model based on the principle of Virtual Wedge operation and the measured output variation with dose rate to quantitatively describe Virtual...

This study aimed to theoretically evaluate soil thrust on a clay slope as reaction force associated with the motion of an off-road tracked vehicle. The existing concept potential failure modes block flat ground has extended determine sloped ground. Based upper-bound limit analysis, under most critical was derived for three modes: block, triangular-wedge, and trapezoidal-wedge failures. Specific...

BACKGROUND AND PURPOSE Percutaneous vertebroplasty can aggravate spinal canal narrowing, especially in patients with preoperative retropulsion. The purpose of this study was to evaluate changes in spinal canal dimension during percutaneous vertebroplasty for osteoporotic fractures with retropulsion. MATERIALS AND METHODS We reviewed all cases of osteoporotic vertebral fractures treated with v...

In our earlier work, we introduced a definition for the electric charge "fractional-order" multipoles using the concept of fractional derivatives and integrals [l]. Here, we utilize that definition to introduce a detailed image theory for the two-dimensional (2-D) electrostatic potential distributions in front of a perfectly conducting wedge with arbitrary wedge angles, and for the three-dimens...

An experimental investigation is conducted to calculate the shock standoff (SSO) distance in front of an acute-angled wedge. For this experimentation, simple water flows channel analysis is carried out. The flow velocity is varied from 13.2 cm/s to 25.5 cm/s increasing in steps of 1 cm/s. A velocity of 13.2 cm/s corresponds to Froude number 1.13 and velocity of 25.5 cm/s to Froude number 1.41. ...

OBJECTIVE The purpose of this study is to investigate the incidence of new compression and to analyze factors that influence the fractures in adjacent levels after percutaneous vertebroplasty (PVP). METHODS This retrospective study examined 206 patients who had undergone PVP for single level osteoporotic or osteopenic compression fractures during the last seven years in our department. After ...

The present study aimed at examining the curative effect of modified posterior operation on treatment of Kümmell's disease. About 30 patients of Kümmell's disease with complete image and clinical data treated during June 2004 to July 2013 were conducted with anterior and posterior approaches, respectively. Kyphotic Cobb angle, fractured vertebra wedge angle, and the anterior and posterior heigh...

Purpose To evaluate the radiologic and functional outcomes of medial open wedge high tibial osteotomy (HTO) combined with arthroscopic procedure in patients with medial osteoarthritis. Materials and Methods From June 1996 to March 2010, 26 patients (32 knees) who underwent medial open wedge osteotomy and arthroscopic operation for medial osteoarthritis were retrospectively reviewed. Measureme...

Our aim was to compare the degree of patellar descent and alteration in angle of the inclination of the tibial plateau in lateral closing-wedge and medial opening-wedge high tibial osteotomy (HTO) in 51 consecutive patients with osteoarthritis of the medial compartment and varus malalignment. Patellar height was measured by the Insall-Salvati (IS) and the Blackburne-Peel (BP) ratios. The tibial...

BACKGROUND AND PURPOSE Percutaneous vertebroplasty is an effective tool for the relief of pain caused by osteoporotic spine fractures. Our purpose is to evaluate this technique and its effectiveness in restoring the height of such fractures. METHODS Forty osteoporotic vertebral body fractures in 30 consecutive patients (24 female, six males; mean age, 70 years) were analyzed retrospectively, ...