Study Of The Spinal Motor Ability In Patients With Ankyloing Spondylitis

Background:Ankylosing spondylitis,axial involvement as the principal,is seronegative spondyloarthropathy,as a kind of systemic autoimmune disease that characterized by chronic inflammation of the spine and the sacroiliac joints.In severe cases,it can cause deformity of spine and ankylosis of joint,with long course of disease,high misdiagnosis rate,high disability rate and low cure rate.In china, the prevalence of Ankylosing Spondylitis was about0.3%. This disease incidence in male majority,involve the young men under thirty those whose mind and body at their best.Meanwhile,it’s one of the mian reason to cripple the young.In the diagnosis of Ankylosing Spondylitis,clinical symptoms and signs play an great important role.The major clinical manifestations of AS are muscles pain,lower back stiff and activity limitation,spinal deformity,peripheral arthritis or extra articular symptoms.Clinically physical examination shows straight leg raising test(SLRT),Faber-Patrick test, percussion pain on sacroiliac joint are positive along with the abnormal indexes of from finger to ground,chest expansion,distances from jaw to presternum and so on. This disease features in fibrosis and bony ankylosis of all the spine joints as well as the sacroiliac joints,which are emerging little by little.In the later period, all the bones turn stiffly and nothing can reverse the state of the illness. As one of the characteristics of the disease progression, rigid spine can generally result in decline of spinal mobility,which is significant in estimating the disease progression and the quality of those patients’life.In recent years, literatures mostly probe the AS in terms of the spine movement ability on the basis of the following indexes,such as from occipital bone to wall,from finger to ground, distances from jaw to presternum,chest expansion, Schober test and so on,which is regarded as the guideline of rehabilitation principle for the AS sufferers by moving your body to keep away from disability.And all these statistics are a measurement of the range of stretching and flexing as well as the forward and backward displacement of the spine in a lateral position.Although those can to some extent reflect the motion pattern of the spine,the motion of the spine comes down to a three-dimensional movement.The normal spine contour contains lordosis of the neck and lumbar,kyphosis of the thoracic and sacrum,the soft tissue of the spine and its surrounding ligaments associated jointly maintain the spine’s natural bent and balance.Any changes on the spine of the normal curve spine may be a anomalous signal,as the method of measurement of spinal contour,there is an great significance in the clinical diagnosis of spinal disorder or ergonomic research. The movement of the spinal segments is a composite of the six movements as up/down,front/rear,left/right shift,flexion/extension,left/right bending,left/right axial rotation angle,having a large degree of freedom,and is a three-dimensional motion,to ensure the accuracy of its measurements need to adopt a three-dimensional measurement system technology.However,the method which applied with messure of the ability of spinal movement carried out as a foreign application the spine measuring instrument (Spinal mouse) to the greatest degree reflects the spine movement ability.From the actual effect of our previous applications,Spinalmouse exists the instrument limitations of high cost.It requires we must achieve Spinalmouse’s function that measurement of spinal motor by a more economical and practical method. In recent years, the deepening of the computer image processing and computer vision research,reverse engineering,modern manufacturing technology,the rapid development of multimedia technology,make it possible that the use of three-dimensional measurement techniques to determine the spatial location of the object. The maturity of the technology to make three-dimensional measurement system plays an increasingly important role in the field such as engineering,quality control,robotics, high-speed line detection,medical diagnostics,computer semiautomatic design, computer-aided manufacturing and the Criminal Investigation.Literature introduces all aspects of the three-dimensional measurement system. The system not only can quickly obtain a large number of three-dimensional data,but obtained large measurement range with minimal footprint, measurement accuracy and measurement speed,therefore can fully meet the corresponding requirements and greatly increase the range of applications of the testing equipment.In a word,the three-dimensional measurement system will become the future mainstream of development in the near future with visual technology continues to mature and develop.Objective:This study was designed to study the evaluation of Spinal mobility of patients with ankylosing spondylitis using Spinalmouse and explore a effective and economically viable method to measurement exercise capacity of patients with ankylosing spondylitis.Methods:1.Use Spinalmouse that has been widely recognized in the international,to measure the motor abitity of spine on the patients with ankylosing spondylitis,to understand how to achieve and the methods of capacity assessment using Spinalmouse to evaluate the motor abitity of spinal on ankylosing spondylitis patients.2.The computer vision system is an important part in the three-dimensional measurement system and the camera calibration is used to determine the camera geometric and optical characteristics (internal parameters) or it to be a improtant way that the three-dimensional position and orientation of one of the world coordinate system (external parameters) an important way to the camera structure. Camera calibration computer vision technology is the base of camera calibration,in many cases,it is closely related to the overall performance of the computer vision system with camera calibration accuracy. The parameters of cameras is calibrated accurately inside and outside can not only directly improve the measurement accuracy,and lay a good foundation for subsequent stereo matching and3D reconstruction.Therefore, we need to design a set of accurate camera calibration methods to reconstruction three-dimensional processand and high measurement accuracy of the system to achieve the accurate measurement of the three-dimensional measurement.3.we have to understand the curvature of the spine as a whole,and activities at the same time,but also needs to be refined to the curvature of each vertebral body and activity,which requires that each vertebral is refined the entire spine on the whole spine to guide further single the research of vertebral curvature and activity. We will review randomly50full spine X-rays of healthy normal,which collected by two seniority diagnostic radiology physicians who work in Nanfang Hospital,the affiliated hospital of Southern Medical university,and they did not participate in the research, which were took from March2010to December2012,and then the whole spine DR pieces collected are saved by dicom format and opened in eFilm Workstation image processing workstation environment,measurement in turn center distance from the chest1vertebral body center to chest2vertebral body center,followed by of the lateral view distance,chest2vertebral Center to thoracic vertebral center......until the L4vertebral body center to the L5vertebral center distance,and is derived by adding the total length from the chest1center to L5center,and ultimately obtained for the percentage of the total length of each of the segments occupied from the center of the chest1to the center of the lumbar5,refining the percentage of each vertebral segment by in the form of a single vertebral segments to the proportion of the total length.4.Normal spine contour contains lordosis of the neck and waist,kyphosis of the chest and sacral,the entire spine and its surrounding ligaments associated soft tissue to maintain the spine’s natural bent and balanced,the curve change of normal spine may be the performance of spine abnormal signal,it has,as the way to measure the contour of spine,an important significanceas in the clinical diagnosis of spineal disorder and human body engineering ergonomic research and so on.Spinal segment movement is up/down, front/rear and left/right shift, and flexion/extension, the six movements composite of the left/right bending and left/right axial rotation angle,larger DOF,belonging to the three-dimensional motion,to ensure the precision of the measurements,it’s necessary to adopt a three-dimensional measurement system technology.For the study of high-precision three-dimensional measurement of human spine morphology is also less, this paper take means using markers to solve feature extraction accuracy problems,and the reconstruction of the three-dimensional coordinates of marker points,according to the actual point of the three-dimensional coordinates to ahieve curve fitting of spine morphology.In order to further improve the accuracy,our group carry out a detailed discussion and research on template size scaling,the scaling parameter selection,the camera placed to,through appropriate selection of the world coordinate system,to solve the binocular stereo vision depth reconstruction error centralized situation.Finally,the system parameter optimization of the final experimental measurements.Curve fitting by the reconstruction of the three-dimensional coordinates of points in three body postures, and validation.Results:l.Spinalmouse can achieve measuring angle of each segment of the spine in upright,flexion,extension postures,thoracic and lumbar curvature,back length,spine overall outline information and calculate the thoracic, lumbar, sacral and the range of bending and stretching of the entire spine.2.Three-dimensional measurement after calibration of the length of the checkerboard obtained value.The measured value and the relative error after normality test P value less than0.001,and the length of each grid error is about0.157mm.The relative error is of±0.394%.Be able to meet a large part of the geometric measurement accuracy requirements of less than0.5mm.Known now generally recognized internationally as a spine morphometric tools Spinalmouse, which measurement accuracy in the back of the repeated measurements for the same patient at the same posture resulting length is<lcm,and the length measurement accuracy is±0.5%.The measurement accuracy of the device is more accurate compared to it.3.The standard back length can be represented the contour by scaling.Each segment’s percentage proportion can be expressed as standard back length. The percentage of the total length in the form of single vertebral segments,which refine each of the vertebral segments occupied proportion of perspective.From this point of view,the data of50healthy people is tested with Shapiro-Wilk normality.Draw a single T1-L5spinal segments accounted for this overall length percentage data are in line with the normal distribution. Whereby available T1vertebral to L5vertebral mean values instead of the ratio of the length of each segment of the total length of each group.4.R2values were greater than0.8in three postures,fit better.We can consider we design three-dimensional measurement system can achieve the reconstruction of the human spine morphology and combined with a single T1-L5spinal segments accounted for this overall length percentage data we discussed before,We can consider according to our design of3d measurement system can better realize the human body in the form of spinal reconstruction combined with the above discussion can serve as a kind of implementation of the whole spine curvature and the curvature of a single segment and the positioning of the feasible measurement method.Conclusions:1.Spinalmouse can achieve non-invasive radiation-free exercise capacity of patients with ankylosing spondylitis spine evaluation and high measurement accuracy, the result is simple and clear, easy to understand,but there are higher costs and other issues,so we hope to design their ownout a low cost alternative to Spinalmouse.2.The three-dimensional measurement system has the advantage of faster and more accurate,and anthropometric intelligent automation is the future development trend.Advanced body measurement technology is the key to solve this problem.3.Three-dimensional measurement system measurement accuracy is slightly improved compared with the generally recognized international Spinalmouse.On the basis of this,its cost is greatly reduced. So it is a necessary condition for an advanced technology to promote our real national circumstances.4.Three-dimensional measurement system can try to rebuild the curve of the spine through the space marked point,the next step will be the artificial segmentation of the curve,and explore possible methods of measuring the angle between the vertebrae.This is the need for further study in the future direction.