Risk analysis for subsequent fracture of osteoporotic fractures in Chinese women over age 60: a nationwide cross-sectional study.

Prevention of subsequent fracture is a major public health challenge in the field of osteoporosis prevention and treatment, and older women are at high risk for osteoporotic fractures. This study aimed to examine factors associated with subsequent fracture in older Chinese women with osteoporosis. We collected data on 9212 older female patients with osteoporotic fractures from 580 medical institutions in 31 provinces of China. Higher odds of subsequent fractures were associated with age of 70-79 years (OR 1.218, 95% CI 1.049-1.414), age ≥ 80 (OR 1.455, 95% CI 1.222-1.732), index fracture site was vertebrae (OR 1.472, 95% CI 1.194-1.815) and hip (OR 1.286, 95% CI 1.041-1.590), index fracture caused by fall (OR 1.822, 95% CI 1.281-2.591), strain (OR 1.587, 95% CI 1.178-2.139), no inducement (OR 1.541, 95% CI 1.043-2.277), and assessed as high risk of fracture (OR 1.865, 95% CI 1.439-2.416), BMD T-score ≤ -2.5 (OR 1.725, 95% CI 1.440-2.067), history of surgery (OR 3.941, 95% CI 3.475-4.471) and trauma (OR 8.075, 95% CI 6.941-9.395). Low risk of fall (OR 0.681, 95% CI 0.513-0.904), use of anti-osteoporosis medication (AOM, OR 0.801, 95% CI 0.693-0.926), and women who had received fall prevention health education (OR 0.583, 95% CI 0.465-0.730) associated with lower risk. The areas under the curve of the prediction model was 0.818. The sensitivity was 67.0% and the specificity was 82.0%. The prediction model showed a good ability to predict the risk of subsequent fracture in older women with osteoporotic fractures and are suitable for early self-measurement which may benefit post-fracture management.

Synchronized 3D Printing and Corona Charging for One-Step Prototyping of Polarized Polylactic Acid Electrets.

Three-dimensional (3D) printing technology is advantageous in the fast prototyping of complex structures, but its utilization in functional material fabrication is still limited due to a lack of activation capability. To fabricate and activate the functional material of electrets, a synchronized 3D printing and corona charging method is presented to prototype and polarize polylactic acid electrets in one step. By upgrading the 3D printer nozzle and incorporating a needle electrode to apply high voltage, parameters such as needle tip distance and applied voltage level were compared and optimized. Under different experimental conditions, the average surface distribution in the center of the samples was -1498.87 V, -1115.73 V, and -814.51 V. Scanning electron microscopy results showed that the electric field contributes to keeping the printed fiber structure straight. The polylactic acid electrets exhibited relatively uniform surface potential distribution on a sufficiently large sample surface. In addition, the average surface potential retention rate was improved by 12.021-fold compared to ordinary corona-charged samples. The above advantages are unique to the 3D-printed and polarized polylactic acid electrets, proving that the proposed method is suitable for quickly prototyping and effectively polarizing the polylactic acid electrets simultaneously.

Efficacy of 'breath holding at ease' during CT pulmonary angiography in the improvement of contrast enhancement in pulmonary arteries.

INTRODUCTION: The aim of this study is to assess whether breath-hold at ease by patients during the CT pulmonary angiography (CTPA) will improve contrast enhancement in pulmonary arteries. METHODS: Retrospective review was conducted on 51 consecutive CTPA studies undertaken in the traditional method of patients taking deep inspiration and breath-hold immediately prior to scanning, and subsequently 75 consecutive CTPA studies with patients breathing-holding at ease immediately prior to and during the scanning. Attenuation values in pulmonary arteries of different anatomical levels in both groups were measured in Hounsfield unit (HU). Results were compared between the two groups. RESULTS: The mean attenuation value in pulmonary arteries including pulmonary trunk, main and proximal pulmonary arteries calculated in HU in the 'deep inspiration and breath-hold' group was 327 HU (95% confidence interval: 315 to 339 HU). The mean attenuation value in pulmonary arteries in the 'breath hold at ease' group was calculated to be 390 HU (95% confidence interval: 381 to 399 HU); that is, an overall 17.95% increase (P-value < 0.0001) in attenuation value in this group. CONCLUSIONS: By asking patients to breath-hold at ease instead of taking deep inspiration and breath hold prior to CTPA scan can effectively improve contrast enhancement in pulmonary arteries, therefore producing a higher-quality CT pulmonary angiography scan.