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Background context Periosteum, endosteum, and bone are innervated by sensory nerves expressing calcitonin gene-related peptide (CGRP), which is a known osteoanabolic peptide and plays an important role in fracture healing and spinal fusion. Synthesis and release of CGRP are found in sensory neurons located in the dorsal root ganglions (DRGs) and can be upregulated by electrical stimulation (ES) at DRG. Purpose To prove our study hypothesis on the potential of precise ES at DRG through implantable microelectrical stimulation system (IMESS) for its effect on promoting spinal fusion in a rat model without decortications and bone grafting . Study design An experimental animal study. Methods A novel IMESS was developed for stimulating L4–L6 DRG in rats. Sixteen rats were used and divided equally into the control group without ES and the ES group, with a daily 20 minutes ES to DRG for 6 weeks. At the end of 6 weeks, radiography and microcomputed tomography were conducted to evaluate new bone formation and spinal fusion. Bilateral L4–L6 DRGs were harvested for immunohistochemistry and quantification of neurons with upregulated CGRP expression. Results In the ES group, rate of radiographic fusion with complete and uninterrupted bony bridging was 100% (8/8) at the right L4/L5 transverse processes and 75% (6/8) at the right L5/L6 transverse processes. Bony callus formation was absent at the left L4–L6 transverse processes in the ES group and in bilateral L4–L6 transverse processes in the control group. Conclusions We proved for the first time that precise ES at DRG through IMESS effectively promoted intertransverse process fusion in rat model without decortications and bone grafting . Electrical stimulation at DRG might be an attractive minimal invasive bioengineering approach and an alternative therapy for intertransverse process fusion that is increasingly being used for the treatment of degenerative spine disorders. [ABSTRACT FROM AUTHOR]

Summary: Clinical imaging plays an integral role in disease diagnosis and patient care. It is good for healthcare professionals such as nurses to acquire skills and knowledge in radiological examination requests and image interpretation, since this kind of role extension provides more personalized patient care and streamlines the service. This study described the development of a clinical imaging portal to facilitate independent learning in image interpretation and explored factors affecting intentions to use the portal based on the technology acceptance model (TAM), with the computer self-efficacy construct as an external variable. One hundred and twenty-eight nursing students participated in this survey study and the results indicated that the portal was perceived as easy to use, useful and satisfying. Structural equation modeling (SEM) showed that attitude toward using the portal exhibited the strongest total effect on behavioral intention to use, followed by perceived ease of use and computer self-efficacy. Although some TAM researchers have suggested that the inclusion of attitude is not meaningful, we argue that attitude should continue to be used in subsequent research. [Copyright &y& Elsevier]

Abstract: Computed radiography (CR) and a combined ultrasound (US) approach involving two-dimensional (2-D) and three-dimensional (3-D) ultrasonography with ultrasonometry were employed to evaluate their respective efficacies in monitoring bone regeneration during rabbit tibial distraction osteogenesis (DO). Results demonstrated that 2-D and 3-D ultrasonography depicted bone callus growth changes during distraction while CR could not. Evaluation of callus speed of sound, acoustic reflection and attenuation showed significant linear changes over time during early DO stage (p < 0.05). However, surrogate measure of callus density by CR only showed such significant linear changes during consolidation (p < 0.05). Also, callus speed of sound and acoustic reflection during early DO stage showed strong predictions to the bone mineral density and microstructural properties (adjusted-R2 = 0.43–0.67) of consolidated bone callus measured at the treatment end-point by microcomputed tomography. Findings of the present study indicated a preferred use of the combined US approach over CR in the early monitoring of bone regeneration during DO treatment. [Copyright &y& Elsevier]

Abstract: This study investigated regional volumetric trabecular bone mineral density (tBMD) and bone area at the ultradistal tibia in Chinese women using peripheral quantitative computed tomography. Fifty-six postmenopausal women aged 47–62 yr participated in BMD measurements at baseline and 22 of them were followed at both 1-yr and 3-yr follow-up scans. Regional baseline tBMD, rate of annual bone loss, and trabecular bone area were determined. Baseline measurements showed that the tBMD of both the posterior (252.9±63.4 mg/cm3) and medial (226.6±68.9 mg/cm3) regions was significantly higher than that of the anterior (126.3±61.9 mg/cm3) and lateral regions (149.8±50.6 mg/cm3), respectively (p <0.001). Both the 1-yr and 3-yr follow-up measurements showed that there was significant physiological annual tBMD loss on an average of 1.61%, at the four regions. Inter-slice regional tBMD and trabecular bone area measurements demonstrated a significant linear decrease from the distal to proximal aspects (p <0.001). Findings suggest that dynamic compressive loading during the heel strike and the body weight vector shifting toward the medial aspect during the stance phase in a normal gait might account for the regional tBMD differences. Increased tBMD and bone area toward the distal tibial endplate may adapt to withstand the axial impact loading. However, the low-impact weight-bearing nature of a normal gait may not be osteogenic to prevent regional bone loss. An exercise program specific to the women at risk should be contemplated. [Copyright &y& Elsevier]