silicon and Fractures--Bone

We attempted to determine why after an exceptionally hard winter deer antlers fractured more often than usual. We assessed mechanical properties, structural variables and mineral composition of deer antlers grown in a game estate (LM) after freezing temperatures (late winter frosts, LWF), which resulted in high incidence of antler fractures despite being grown later in the year, and those grown after a standard winter (SW). Within each year, specimens from broken and intact antlers were assessed. LWF was associated with reduced impact energy (U) and somewhat reduced work to peak force (W), Young's modulus (E) and physical density, as well as cortical thickness. LWF was associated with considerably increased Si and reduced Na. In each year, broken antlers had lower Mn, P and physical density, and they had more Na and B than unbroken antlers. Because no such effect was found in farmed deer fed whole meal, and because freezing in plants usually produces an increase in Si content, which in turn reduces Mn, it is likely that LWF produced a diet rich in Si and low in Mn. Because antlers are grown transferring calcium phosphate from the own skeleton and Ca/P levels were slightly reduced, it seems likely that Mn reduction may have increased antler fractures. A comparison between farm deer and those in another game estate (LI) also shows a link between lower Mn content and lower W. Thus, small changes in minor bone minerals, probably induced by diet, may have marked effects in mechanical properties of bone.

Topics: Animals; Antlers; Biomechanical Phenomena; Bone and Bones; Deer; Diet; Fractures, Bone; Manganese; Plants; Rain; Seasons; Silicon; Temperature; Weather

The UK Food Standards Agency (FSA) convened a group of expert scientists to discuss and review UK FSA- and Department of Health-funded research on diet and bone health. This research focused on the lifestyle factors that are amenable to change and may significantly affect bone health and the risk of osteoporotic fracture. The potential benefits of fruits and vegetables, meat, Ca, vitamins D and K and phyto-oestrogens were presented and discussed. Other lifestyle factors were also discussed, particularly the effect of physical activity and possible gene-nutrient interactions affecting bone health.

Topics: Bone and Bones; Calcium; Consensus; Diet; Estrogens; Female; Fractures, Bone; Fruit; Humans; Male; Meat; Nutritional Physiological Phenomena; Nutritional Status; Osteoporosis; Phytotherapy; Plant Extracts; Silicon; Smoking; Sodium Chloride; Ultrasonography; United Kingdom; Vegetables; Vitamin D; Vitamin K

The purpose of this study was to evaluate a large-area, flat-panel X-ray detector (FD), based on caesium-iodide (CsI) and amorphous silicon (a-Si) with respect to skeletal radiography. Conventional images were compared with digital radiographs using identical and reduced radiation doses.. Thirty consecutive patients were studied prospectively using conventional screen-film radiography (SFR; detector dose 2.5 microGy). Digital images were taken from the same patients with detector doses of 2.5, 1.25 and 0.625 microGy, respectively. The active-matrix detector had a panel size of 43 x 43 cm, a matrix of 3 x 3K, and a pixel size of 143 microm. All hard copies were presented in a random order to eight independent observers, who rated image quality according to subjective quality criteria. Results were assessed for significance using the Student's t -test (confidence level 95%).. A statistically significant preference for digital over conventional images was revealed for all quality criteria, except for over-exposure (detector dose 2.5 microGy). Digital images with a 50% dose showed a small, statistically not significant, inferiority compared with SFR. The FD-technique was significantly inferior to SFR at 75% dose reduction regarding bone cortex and trabecula, contrast and overall impression. No statistically significant differences were found with regard to over- and under-exposure and soft tissue presentation.. Amorphous silicon-based digital radiography yields good image quality. The potential for dose reduction depends on the clinical query.

Topics: Aged; Bone Diseases; Female; Fractures, Bone; Humans; Male; Middle Aged; Prospective Studies; Radiation Dosage; Radiographic Image Enhancement; Silicon

The purpose of this phantom study was to assess the diagnostic performance of a self-scanning, solid-state amorphous silicon (a-Si) detector in skeletal radiography using different exposure parameters.. A flat-panel detector (15 cm x 15 cm), based on a-Si technology with 143 microm x 143 microm pixel size, 1k x 1k matrix, and 12 bit digital output was used. State-of-the-art screen-film radiography (SFR; speed 400, detector dose 2.5 microGy) was compared with a-Si images taken at doses that were equivalent to a speed of 400, 800, 1,250, and 1,600, respectively. A total of 232 segments of long tubular deer-bones (femur, tibia, humerus, radius) had 110 artificial fractures and 112 cortical defects simulating osteolytic lesions. Receiver operating characteristic analysis was performed for 9,280 observations made by four independent observers. Two-tailed Student's paired t test was used for statistical analysis (95% confidence level).. Receiver operating characteristic analysis yielded equivalent results of the a-Si and SFR system. Even at the lowest dose there were no statistically significant differences between both imaging modalities with respect to the detectability of fractures and cortical defects.. The results of this study indicate that a-Si detector technology holds promise in terms of dose reduction in skeletal radiography without loss of diagnostic accuracy.

Topics: Animals; Bone and Bones; Deer; Fractures, Bone; Phantoms, Imaging; Radiographic Image Enhancement; ROC Curve; Silicon; Technology, Radiologic; X-Ray Intensifying Screens

The concept of tenolysis has been in existence for at least 50 years. Its function is to free tendon from posttraumatic scar tissue. To retard the recurrence of rescarring, membrane interposition between tendon and bone has been recommended. In the setting of postfracture extensor tenolysis, I prospectively employed a 3-mm section of passive Hunter rod as an interpositional material in eight consecutive patients. After an average follow-up of 23 months, the patients maintained 92 percent of operatively attained motion; only 56 percent was maintained in six patients without membrane interposition. There was no instance of rod dislocation, rod removal, or adverse silicone reaction. Extensor tenolysis with silicone membrane (Hunter rod) interposition is more predictable and enduring than tenolysis alone.

Topics: Adult; Finger Injuries; Follow-Up Studies; Fractures, Bone; Humans; Male; Prospective Studies; Prostheses and Implants; Range of Motion, Articular; Retrospective Studies; Silicon; Tendons; Tissue Adhesions

Topics: Bony Callus; Fractures, Bone; Humans; Silicon

Topics: Bone Diseases; Calcification, Physiologic; Calcium; Calcium, Dietary; Fractures, Bone; Humans; Potassium; Silicon