ABSTRACT
In the research of artificial joint biomechanics, it is a common method in the world to evaluate the biomechanical properties of the implanted fixtures through experiments . The domestic research started late, and the corresponding testing methods were lacking. There is still no unified standard. In this paper, a complete hardware test system was designed and built around the existing mechanical testing machine, including:binocular vision catcher, torque bearing clamp, film pressure sensor and so on. The system can accurately measure the relative motion angle value, external torque value, and inter pressure value of each joint. It has some reference significance for the forming and standardization of the artificial joints' evaluation system.
Subject(s)
Biomechanical Phenomena , Joint Prosthesis , Motion , Pressure , TorqueABSTRACT
In the research of artificial joint biomechanics, it is a common method in the world to evaluate the biomechanical properties of the implanted fixtures through experiments . The domestic research started late, and the corresponding testing software were lacking. There is still no special software. In this paper, an integrated software test system was designed and built based on the existing hardware system, including:hardware control, data collection, data save, data processing and display. It can directly show the 3D motion trajectory and the angle curve of joints. The system can accurately measure the relative motion angle value, external torque value, and inter pressure value of each joint. It has some reference significance for the development of the artificial joints' evaluation system.
ABSTRACT
Cervical spondylosis is due to degenerative cervical disc and its stimulation or oppression of the adjacent nerves, spinal cord, spinal artery and other tissue caused by clinical symptoms. The cervical spine is an anatomical structure with activity, while the pillow has a certain plastic fixation effect on the cervical spine anatomy. Therefore, the pillow not only plays a health role in the cervical spine, but also plays an important role in restoring the normal physiological curvature of the cervical spine. Based on this, a multi-functional cervical vertebra treatment pillow is designed, which not only has the functions of traction, maintaining different positions of the cervical spine, correcting the cervical curvature and equipment exercises, but also has the functions of voice broadcast and network data terminal.
ABSTRACT
BACKGROUND:Clinical practice verified that percutaneous vertebroplasty in the treatment of osteoporotic vertebral compression fractures obtained obvious curative effects. OBJECTIVE:To compare the therapeutic effect of percutaneous vertebroplasty for treatment for osteoporotic vertebral compression fractures with or without intravertebral cleft, in order to evaluate the efficacy and safety of percutaneous vertebroplasty for treatment of osteoporotic vertebral compression fractures. METHODS:A total of 76 patients with osteoporotic vertebral compression fractures were selected and divided into two groups. Experimental group consisted of 27 patients with intravertebral cleft. Control group comprised 49 patients without intravertebral cleft. After vertebroplasty, visual analogue scale and Oswestry disability index, changes of anterior vertebral height, and types and characteristics of bone cement leakage were compared between the two groups. RESULTS AND CONCLUSION:Visual analogue scale and Oswestry disability index were significantly decreased after treatment in the two groups (P0.05). No significant difference in the height of injured vertebra was detectable between pretreatment and posttreatment in the two groups (P>0.05). These results suggested that vertebroplasty is an effective method for lessening the pain in osteoporotic vertebral compression fractures in patients with or without intravertebral cleft, improving spinal activity function and elevating social activities. However, percutaneous vertebroplasty cannot effectively recover the height of the vertebra.
ABSTRACT
BACKGROUND:Operation is an important measure to improve the function of spinal cord and to stop the pathological progress of multilevel cervical spondylotic myelopathy. There are controversies how to select the optimum operation mode, to reduce postoperative complications and to elevate clinical curative effects. OBJECTIVE:To systematical y review patients’ profiles of multilevel cervical spondylotic myelopathy, and to evaluate the effects of simple anterior approach, simple posterior approach and one stage posterior anterior combined approach on cervical spinal curvature index and functional recovery in patients. METHOD148 sample profiles of patients, who received multilevel cervical spondylotic myelopathy operation in The Affiliated Hospital of Qingdao University and Qingdao Municipal Hospital from February 2000 to February 2008, and met the inclusion and exclusion criteria, were selected. They were divided into simple anterior approach group, simple posterior approach group and one stage posterior anterior combined approach group. The differences in the functional recovery were assessed after treatment using different therapeutic methods. RESULTS AND CONCLUSION:Cervical spinal curvature index was highest in the simple posterior approach group before treatment (P0.05). Significant differences in improvement rate of Japanese Orthopaedic Association Scores were detectable after treatment between the one stage posterior anterior combined approach group and simple anterior approach and simple posterior approach groups (P<0.001). Significant differences in cervical dysfunction index and SF-36 scores were detectable among the three groups before and after treatment (P<0.05). Results indicated that compared with the simple anterior approach and simple posterior approach, decompression through one stage posterior anterior combined approach is a reliable and effective operative procedure for treatment of multilevel cervical spondylotic myelopathy.
ABSTRACT
This paper constructs numerical models of bioprosthetic heart valve and blood. The fluid solid interaction is carried out using penalty function method. The mechanical property of the bioprosthetic heart valve during cardiac cycle is simulated with ANSYS software. Results show that the Von Mises stress concentrates at the junction of attachment edge and coaptation edge. The open time of bioprosthetic heart valve is consistent with that of actural measurement. The peak velocity of blood is in the range of physiology. This model provides more realistic mechanical property of bioprosthetic heart valve during cardiac cycle compared to pure solid model, and facilitates design and optimization of bioprosthetic heart valve.
Subject(s)
Humans , Bioprosthesis , Heart Valve Prosthesis , Heart Valves , Models, Cardiovascular , Prosthesis DesignABSTRACT
<p><b>BACKGROUND</b>Due to racial differences in the morphology of the knee joint and due to most prostheses available in the market being designed using measurements from Caucasians, the objective of this study was to provide the morphometric data of the patella for the southern Chinese population for total knee arthroplasty (TKA), patellar resurfacing, and prostheses design.</p><p><b>METHODS</b>The CT slices of the knee joint were obtained from both knees of 40 Chinese volunteers (20 females, 20 males, and age from 20-25 years) by performing a computer tomographic scan. A 3D model was reconstructed by Mimics software based on the computed tomography images. Six metrical characteristics were measured by digital ruler. Statistical analysis was performed with the SPSS statistical program.</p><p><b>RESULTS</b>The mean, standard deviation and P values of measurements and ratios were calculated using SPSS. All dimensions showed a significant gender difference with P < 0.05, but the six variables of the left and right knees had no statistical significance with P > 0.05. In addition, we studied the relationship between six couples (H-W, H-T, H-HAF, W-T, W-HAF, T-HAF) of the four variables (H: height, W: width, T: thickness and HAF: height of articulating facet) that were measured, which showed a significant correlation.</p><p><b>CONCLUSIONS</b>Examination of the southern Chinese population revealed that males have larger patellae than women. In both genders, comparing data between left and right knees shows no statistically significant difference. Compared with Westerners in previous studies, the patella in our study was thin and small. There was a good linear regression correlation between measurements of the patella. The indirect measurement method on 3D models makes it easy to obtain anatomical data, and the results can provide a region and gender specific database for morphometric measurements of the patella, and can be helpful for designing implants suited for southern Chinese patients.</p>