Calculation Of Contact Area Of Artificial Joints Prosthesis And Cancellous Bone

Artificial joint replacement is an important surgery, the greater the contact areabetween the prosthesis and the host bone is, the more evenly the stress of the artificialjoint is, the less likely the artificial joint sends stress shelter, and the survival rate ofprostheses is higher, therefore, the size of the contact area between the prosthesis andthe host bone is an important symbol of whether the surgery success or not. In thispaper, the data sources come from CT images with high precision of artificial jointprostheses. Based on the image processing to calculate the contact area between theprosthesis and the bone. Then help the doctor observe the gaps between the prosthesisand the bone tissue after the operation, and determine the stability of the prosthesis,diagnose artificial joint loosening condition early, provide reliable basis forrehabilitation. The main research content includes the following four parts:Medical image pre-processing:because the medical image has somecharacteristics, such as: uneven fuzzy boundaries, large range of grey level, vulnerableto strong noise pollution and so on. The stand of image pre-processing influence thefollow-up operation include image segmentation,image3D reconstruction andcalculation of the contact area,so image pre-processing can not be ignored. This articlestart from the image pre-processing, first through a variety of filtering methods formedical image pre-processing,such as:image filtering,image enhancement and soon,select method with better effect depend on analysis and comparison, effectivelyfilter the noise in medical image.Medical image segmentation: The traditional model of multiphase Chan-Vese iseasy to cause empty phase problem during the multi-region segmentation, to solve thisproblem,it proposes an improved medical image segmentation algorithm,the algorithmintegrates Chan-Vese model, mathematical morphology, complex multiphase level setssegmentation algorithm, first,through iterative etching operation to extract the outlineof the medical image, and then the medical image is segmented by the Chan-Vese model based on the complex multiphase level sets, finally the medical image is dilatediteratively by using morphological dilation to restore the image.using this algorithmcan solves the multi-regional medical image segmentation problem well, and reducesreduce the empty phase, and has a very good segmentation effect on the edge of theimage.Medical image3D reconstruction: Marching Cubes is a classical algorithm in theface paint, this algorithm has some problem, during3D reconstruction there willappear ambiguity,and low efficiency problem and so on, in response to this issue, thispaper proposes a rapid reconstruction methods to eliminate ambiguity, effectivelyimprove the accuracy and speed of the reconstruction.The calculation of contact area: Based on Marching cubes algorithm, this paperproposes an improved algorithm to estimate3D object surface area, using theMATLAB function gin put() for interactions, to obtain the input data(boundary contactpixels),the pixels obtained will be introduced to the MC algorithm to building thecontour surfaces. connect all the contour surfaces to form the surface of the objectcontour surface. Count the number of occurrences of each voxel and weights, multiplythem and accumulate them, then the contact surface between the artificial joints andprosthesis can be estimated. Judging the artificial joint loosening condition by thecontact area, it has strong clinical significance and value.