Search results for "Rachis"
showing 10 items of 20 documents
Whole-body vibration and disorders of the spine
1987
This cross-sectional study is based on interviews and medical examinations of 352 operators of earth-moving machines who had been exposed to whole-body vibrations for at least three years. In addition, available X-rays showing different parts of the spines of 251 machine operators who had been exposed to vibration for at least ten years were used for evaluation. One hundred and forty-nine of the operators were asked about discomfort occurring immediately after an eight-hour work shift. The group of exposed persons was compared with a control group of 215 non-exposed persons. The percentage of subjects reporting spinal discomfort was much higher for the exposed group than for the non-exposed…
SPECT Bone scintigraphy of benign and malignant lesions of the spine
1989
70 patients were examined with planar and SPECT bone scintigraphy. SPECT proved to be superior over planar bone scanning for imaging of traumatic, inflammatory, and malignant bone lesions. SPECT provides three-dimensional information and, therefore, delineates the exact location and extension of lesions. It also has a higher sensitivity than planar bone scintigraphy. The three-dimensional bone scan generates complementary diagnostic information which often facilitates an adequate therapy protocol.
A reanalysis of spinal motion during vibration
1987
Calibrated film of the motion of the lumbar spine during vibration was reanalysed, making use of a number of computer based techniques to improve accuracy and reduce measurement noise. The results demonstrated resonant behaviour at about 4 Hz and indicated that at vibration levels of the order of 1 m/s2 there exists bending of the order of 1° (peak to peak) between adjacent vertebrae in the lumbar spine. The bending is complex and involves phase differences along the spine and possibly a rocking motion of the pelvis.
Determination of aflatoxins in peanuts by matrix solid-phase dispersion and liquid chromatography
2003
A new method based on matrix solid-phase dispersion (MSPD) extraction was studied to determine aflatoxin B1, B2, G1 and G2 from peanuts. Optimization of different parameters, such as type of solid supports for matrix dispersion and elution solvents were carried out. The method used 2 g of peanut sample, 2 g of C18 bonded silica as MSPD sorbent and acetonitrile as eluting solvent. Recoveries of each aflatoxin spiked to peanut samples at 2.5 ng/g (5 ng/g for aflatoxin G2) level were between 78 and 86% with relative standard deviations ranging from 4 to 7%. The limits of quantification ranged from 0.125 to 2.5 ng/g for the four studied aflatoxins using liquid chromatography (LC) with fluoresce…
Overland flow generation on hillslopes of complex topography: analytical Solutions
2007
The analytical solution of the overland flow equations developed by Agnese et al. (2001; Hydrological Processes15: 3225–3238) for rectangular straight hillslopes was extended to convergent and divergent surfaces and to concave and convex profiles. Towards this aim, the conical convergent and divergent surfaces are approximated by a trapezoidal shape, and the overland flow is assumed to be always one-dimensional. A simple ‘shape factor’ accounting for both planform geometry and profile shape was introduced: for each planform geometry, a brachistochrone profile was obtained by minimizing a functional containing a slope function of the profile. Minima shape factors are associated with brachist…
Operative Treatment of Scoliosis With Cotrel-Dubousset-Hopf Instrumentation
1997
Study design This study analyzes the effects of a new anterior spinal instrumentation system and the results of use in 50 patients with scoliosis. Objectives Anterior spine systems are reviewed. The principles of a new anterior spinal instrumentation system allowing for postoperative care without external support are discussed. Summary of background data Numerous different implants have been presented in the literature for anterior spinal surgery. Nevertheless a primary stable anterior instrumentation was not available for multisegmental procedures until now, and the restoration of lordosis in the lumbar spine was very difficult with the common devices. The development of more stable device…
Development of scoliosis in myelomeningocele. Differences in the history caused by idiopathic pattern.
1993
The natural history of scoliosis in the literature concerning the idiopathic and neuromuscular scoliosis in myelomeningocele patients (MMC) are compared to our own results in 12 patients with MMC and 89 patients operated because of an idiopathic scoliosis. According to known experiences the natural history of scoliosis in MMC is progression even after the end of growth. The chance of developing a scoliosis increases with the patients, age and the level of the lesion. The higher the level of paralysis the more common is a spinal deformity. In literature the progression rate of MMC scoliosis is 2.5-3.5 degrees per year, with the idiopathic pattern 0.5-0.65 degrees per year after end of growth…
Mehrsegmentale Fusion der Skoliose bei Duchenne-Muskeldystrophie
2008
Operations in scoliosis in patients suffering from an advanced stage of Duchenne muscular dystrophy are associated with a higher risk due to the extent of the curves, the respiratory insufficiency and frequent cardiomyopathia. Progressive scolioses in 20 wheelchair patients with an age between 10.5-18.3 years (mean 14.6 years) were treated by CDI. The mean preoperative angle in this group was 70.6 degrees, the postoperative angle 31.2 degrees (mean correction 39.4 degrees or 55.8%). The preoperative lordosis of the lumbar spine (mean angle 4.1 degrees) was corrected to 17.8 degrees postoperatively. The average intraoperative blood loss (2300 ccm) was evident more compared with idiopathic sc…
Historical Part—Calculus of Variations
2018
The calculus of variations is an old mathematical discipline and historically finds its origins in the introduction of the brachistochrone problem at the end of the 17th century by Johann Bernoulli to challenge his contemporaries to solve it. Here, we briefly introduce the reader to the main results.
Physical loading and performance as predictors of back pain in healthy adults. A 5-year prospective study.
1996
We investigated muscle strength, aerobic power, and occupational and leisure-time physical loading as predictors of back pain in a 5-year follow-up study. A cohort of 456 adults aged 25, 35, 45 and 55 years, free of back pain, participated in measurements of anthropometric characteristics, aerobic power and muscle strength characteristics at baseline. The subjects' levels and types of physical activity and occupational physical loading were also determined. At 5 years after the baseline examinations 356 of these subjects (78.1 %) were reached by mail, and 262 of them (73.6%) properly completed and returned a questionnaire including a detailed back pain history for the 5 years following the …