2006, 21(3):169-171. DOI: 10.3871/j.1004-7220.2006.3.171.
Abstract:Objective To understand the necessity, feasibility and instancy of digitization of scientificparameters in medical biomechanical research; to elucidate the development process of digital humanand digital medicine research in China and abroad, and to prospect the foreground of digital medicine.Method The information of development of digital human and digital medicine was collected and analyzedin this research field. Results The development of digital human research in China and abroad weresummarized. The future development direction and the detail which should pay more attention were broughtforward. Conclusions Digitalization can improve the quality and efficiency of medical biomechanicalresearch. Digital medicine has the great bright future.
2006, 21(3):172-178. DOI: 10.3871/j.1004-7220.2006.3.178.
Abstract:Mechanical Virtual Human of China is a key research project supported by National Natural Science Foundation.A human musculoskeletal system will be built, and this system will be able to export transformed individualizedmusculoskeletal geometric model for specific human parameters. Motion capture system will be employed to measurehuman motion and results will be transformed into musculoskeletal model motion. Through kinematics, kinetics and forceanalysis, joint and muscle forces can be determined for whole process of a specific motion. The musculoskeletal systemis also a finite element model, and FE analysis can be performed for global or local skeletal components. A large scalesoftware system will be developed to support all these calculations and analyses, and this software system will findwide applications in such areas as medical engineering, medical instrument design, physical and art education, ergonomicsand traffic accident analysis.
2006, 21(3):179-182. DOI: 10.3871/j.1004-7220.2006.3.182.
Abstract:Objective To establish high resolution image dataset of Chinese digital human male with a 0.2 mm intervalsection. Methods A Chinese male cadaver was perfused with red glutin through carotid and fixing the shape by frozen,then embedded in a special mould with a erectly position. The embedding block was clamped only once and milledcontinually. The dataset was established by the images, which were all collected by the PhaseOne H25 digital camera.Results Totally we got 9 320 section images by RAW format with a resolution of 4 080×5 440 pixels and per sectionimage size is 27.5 M.The size of Chinses digital Human Male database with RAW format is 260 G. Conclusions The highresolution image dataset of Chinese digital human male is the first high resolution image dataset among all of the knowndatasets. Due to used the high resolution digital camera with 22 million pixes, the organic borderline and the tissue ,forexample vascular,adipose,cartilage and bone etc,are very definitude.It is very easy with the PheseOne software,to re-dispose the color and exposure of the section photo and the part of the image wich is interested in an analysis.
2006, 21(3):183-186. DOI: 10.3871/j.1004-7220.2006.3.186.
Abstract:Objective To design and implement a new algorithm to transform the images of Chinese visual humandataset to vector graphics. Methods A program was developed for the images transformation by using the designedalgorithm. The output file of the program is a vector graphics format of scalable vector graphics (SVG), and it couldcompare the original bitmap with the graphics after transformation according to its profile and color. Results Thedecisive quality image was achieved by adjusting the parameters of the algorithm. The more the color gradient becomes,the harder the calculation will be. Conclusion The implements of transforming the bitmap images could facilitate resolvingthe problem of the interactive format of kinds of platform data of three dimension construction system and to make it moreuniform and standardized.
2006, 21(3):187-191. DOI: 10.3871/j.1004-7220.2006.3.191.
Abstract:Objective To build digitized visible model of the liver and intrahepatic vessels of the visual Chinese man,providing morphological data for virtual surgery of liver. Methods The datum collected from the visual Chinese manliver were used with 3D-reconstruction to build digitized visual model of the liver, and to realize the virtual surgery.Results The quality of the computerized 3D-reconstructed model was distinct and perfect. Any diameter and angle ofthe structures reconstructed could be resected conveniently to acquire the object center, surface and volume of hepaticsegment. Conclusions The creation of visual liver model can be used for the digital anatomy teaching, and for thehepatic virtual surgery of hepatic cancer.
2006, 21(3):192-197. DOI: 10.3871/j.1004-7220.2006.3.197.
Abstract:Objective To display the three dimensional architecture of the white matter fibers in human brain by usingdiffusion tensor tractography, and to investigate the reliability of DTI by comparing with the Chinese visual human dataset.Methods Diffusion tensor imaging was performed with five volunteers, and the data were processed with DtiStudiosoftware to reconstruct the FA, 1-VR, RA, ADC and the color FA map. The reconstructed FA and color FA map werecompared with the sectional images of the Chinese visual human dataset, and the white matter fibers in brain werevisualized by using tractography software and 3D MRI software. Results The three dimensional architecture of whitematter fibers could be clearly visualized on diffusion tensor tractography, including association fibers as the arcuatefibers, the uncinate fascicules, the cingulum, the superior and inferior longitudinal fasciculi; the commissural fibers ascorpus callosum, anterior commissure and fornix; the projection fibers as the pyramidal tract, the visual radiation and themedial lemniscuses. The fibers displayed by diffusion tensor tractography were well consistent with the sectionalimages of the Chinese visual human dataset and the known anatomy. Conclusion The method is a reliable way forstudying the fiber connectivity in human brain.
2006, 21(3):198-202. DOI: 10.3871/j.1004-7220.2006.3.202.
Abstract:Objective Three-dimensional digital structure modeling of human perfused blood vessels for anatomyteaching and virtual clinic surgery. Methods High-resolution and color cryo-sections datasets were acquired withperfused arteries on the Visual Chinese Human Male-No.1. To make the images of datasets dimensional registered and theblood vessel was segmented and classified interactively. The segmented data was reconstructed with parallelismalgorithm. Result The three-dimension structure models of the arteries, veins and heart were established. The modelsof the whole cardiovascular system of Visual Chinese are integrity and real represented for blood vessels perfusion.Conclusion Based on the high-resolution images of VCH cryo-sections and perfusion of artery, the integrity andaccurate human blood vessel models has been constructed.
2006, 21(3):203-207. DOI: 10.3871/j.1004-7220.2006.3.207.
Abstract:Objective Using digital technology to revolve difficult problems of plastic surgery and to the managementand the working efficiency. Methods Computer image analysis technology, database management technology, motioncommunication technology and computer programming technology. Results Established the surgical department digitaldata management system management system, the facial features diagnosis and analysis system, the skin color diseaseevaluation system, psychological measurement system and the communication information system. Conclusions Usingdigital information technology, we can enhance the management and the working efficiency, and improve scientificresearch and the academic level, and it will bring the remarkable society and the economic efficiency, and it is worththoroughly studying.
2006, 21(3):208-211. DOI: 10.3871/j.1004-7220.2006.3.211.
Abstract:Objective To establish a three-dimensional finite element analysis model of the maxillary first molar andvalidate the availability of the model in order to provide the biomechanics basis for prosthesis. Methods With the datumfrom Chinese digital human male No.1, a 3-D structures of enamel, dentin and elements pulp were constructed by thecombination of software Mimics9.1 and Freeform. The meshed models were acquired and finished with Ansys 8.0. Thestresses of the model were analyzed during the perpendicularity loading and the oblique loading, respectively. ResultThe model consisted of enamel, dentin, elements pulp, simulated periodontal membrane and simulated alveolar bone. Themesh division and the elements for each part of the model were: 8303 nodes and 5092 elements for ename; 104883 nodesand 77357 elements for dentin; 19818 nodes and 12116 elements for elements pulp; 2321 nodes and 2278 elements forperiodontal membrane; 31869 nodes and 25264 elements for alveolar bone. The effect of the perpendicularity loading andthe oblique loading indicated that the maximum force was at the 1/3 neck of root. Conclusions Combined usage ofMimics and Freeform, the finite element model constructed has the advantages of intact structure and precise elementswhich can simulate the natural condition and facilitate the further biomechanical research.
2006, 21(3):212-216. DOI: 10.3871/j.1004-7220.2006.3.216.
Abstract:Objective With cryosectional images sequence as data source, bone structure curve and surface modelsare reconstructed. Methods Registration is firstly applied to all the cryo-sectional images through translation, rotationand scaling transforms. Segmentation is then performed on every single image. Characteristic boundary points areselected and fitted into cubic Nurbs curves. B-spline local modification property is utilized to adjust the control polygon forthe fitted curve to better approximate the bone structure boundary. All the segmented curves are added to the curvedatabase with bone name, orientation and cryo-sectional image number combined into an index. Results A comprehensivetechnical solution to bone structure curve and surface modeling from cryo-sectional images is presented, and surfacemodels database is established. Conhclusion The technical solution to reconstruct curve and surface models fromcryo-sectional images is feasible and effective.
2006, 21(3):217-221. DOI: 10.3871/j.1004-7220.2006.3.221.
Abstract:Objective In order to meet the quantitative soft tissues balance measurement requirement in the TKR, a newsoft tissues balance measurement method and system have been developed to help surgeons measure and adjust thesoft tissue in the total knee replacement. Methods Six precise load sensors have been embedded in the measuredevice front, which will be inserted into the cutting gap of the knee joint, to measure the force of the surrounding softtissue. The pressures of these sensors represent the force of the posterior, middle, and anterior positions in the medial/lateral part of the knee joint gap. Furthermore, the device has the function that can change the distance between its upperand lower plate by the mechanical structure for adjusting the space in the knee joint. Results The preliminary testshows that the measurement system can accomplish the force measurement and the distance adjustment in the kneejoint, and display the data of the force distribution in three-dimensional manner in real-time. Conclusion It will be morehelpful for knee dynamics research to combine the data of soft tissue force with the data of distance between the knee joint.
2006, 21(3):222-226. DOI: 10.3871/j.1004-7220.2006.3.226.
Abstract:Objective To investigate the stress distribution in the mandibula with oblique and vertical forces imposedrespectively in different positions of the occlusion surface of the posterior single tooth replacement. Method Thethree-dimensional(3-D) finite element method (FEM) was used to reconstruct the 3-D models of the mandibula, the firstinferior molar and the implant. The max EQV of the mandibula were calculated when oblique and vertical forces wereapplied to different positions of the occlusion surface of the implant. Result The max EQV of the mandibula were foundat the neck of the mandibula around the implant under both oblique andvertical load; The max EQV were significantlydifferent at different points with the same vertical load or with the same load at the different directions. Conclusion Themax EQV of the mandibula are at the neck of the mandibula around the implant and decrease progressively from the neckto the bottom under the oblique and vertical load; The largest max EQV was found at the neck of the mandibula around theimplant when the same load was applied to the distal locations; the various loading conditions play the important role thatcan influence the stress distribution at the neck of the mandibula around the implant.
2006, 21(3):227-230. DOI: 10.3871/j.1004-7220.2006.3.230.
Abstract:Objective To explore the influence of ultimate activity on the stabilization of Scaphotrapeziotrapezoid (STT)arthrodesis. Method 6 fresh cadaver fore-arm were used to make scapholunatum dissociation (SLD) and STTarthrodesis before ultimate activity (50,000 times/per 5°) simulation. Anterior-posterior view and lateral view were takeneach time before and after the motion. Radialoscaphoid angle(RSA)、radialoscaphoid interval (RSI) and length ofscaphoid were measured and the cinch、bent of the Kirschner Wire were recorded as well. All of the wrists werecompared by self-control in the test. Result Comparing with the control groups, the difference of RSA、RSI、lengthof scaphoid and Bent positive ratio of Kirschner Wire showed statistical significance withthe flexion、extenion、radialand deviation beyond 55°, 40° and 10°, respectively (P<0.05). But, the index mentioned above showed no statisticalsignificance (P>0.05) during whole process of the ulnar deviation. Conclusion It is safe for the wrist within the rangeof motion not beyond flexion 55°、extenion 40°、radial deviation 10°, but circumduction should be avoided.
2006, 21(3):231-234. DOI: 10.3871/j.1004-7220.2006.3.234.
Abstract:Objective To measure the biomechanics of memory alloy wire netting ball and investigate the application ofthe kyphoplasty instrument for osteoporosis vertebra compression fracture. Methods Super elasticity netting ball wasmade of memory alloy nickel-titanium wire with different diameter. The loading and unloading strength were measuredafter making the netting ball bipolar and two sides fixed. An instrument was made to extend and compress netting ball toinvestigate its kyphoplasty effect for osteoporosis vertebral compression fracture. Results The maximal loadingstrength increased along with the diameter of memory alloy wire and it could be 162.39 N when using 0.38 mm diameterwire to make netting ball. The kyphoplasty instrument of netting ball could work through pedicle of vertebral arch.Conclusion The kyphoplasty instrument of memory alloy wire netting ball could be a new method to treat osteoporosisvertebra compression fracture, and the clinical effect still need further study.
2006, 21(3):235-240. DOI: 10.3871/j.1004-7220.2006.3.240.
Abstract:Objective To provide the biomechanical basis for ZH transpedicular internal fixator used in thoracolumbarfracture treatment. Methods Trauma models were made from 9 fresh cadavers by Panjabi method and divided into 3 groupswith ZH transpedicular internal fixator, Dick screw and Steffee plate, respectively. To test their biomechanical capability inload-responsive change、centrum intensity、displacement、torsion intensity、stability, rigidity and ultimate strength.Results The results of the test showed that ZH transpedicular internal fixator was much better than the other two oneswith: load-responsive change was much less than that of Dick screw and Steffee plate by 7.2% and 14% at Point A andby 17% and 28% at Point B; Centrum intensity: stress decreased by 7% and 14% at Point A, while at Point B by 17% and29%; The displacement decreased by 24% and 33% vertically, and 40% and 55% horizontally. Conclusions The ZHtranspedicular internal fixator is suitable to popularized in clinic application with its better biomechanical capability.
2006, 21(3):241-245. DOI: 10.3871/j.1004-7220.2006.3.245.
Abstract:The virtual operation is a available training measure, the process of operation will be learned in virtualenvironment by vision, sound and haptic feedback. The haptic feedback is an important and difficult technology, thesignificance and situation over the world is analysed, the algorithm of tissue deformation and haptic feedback devicedevelopment is discussed. The development of the virtual operation will improve the level of digital medicine studying.
2006, 21(3):246-250. DOI: 10.3871/j.1004-7220.2006.3.250.
Abstract:As one of the research methods used in spine biomechanics, the analysis software of three-dimensional finiteelement has got unceasing development with the deeply further understanding for spinal mechanics characteristic bothin China and the world. It has not only promoted the development of finite element technic itself, but also impulse furtherresearch on spinal biomechanics. This paper has reviewed some recently advances, focusing on the concept andprinciple of finite element method, construction of spinal finite element model, application of finite element method incervical spine, lumbar spine and internal fixation device and so on.