Comparison Of Image Analysis And Three-dimensional Motion Analysis Method For The Quantifyingof The Pivot Shitf Test

Objective：The purpose of this study was to compared image analysis withtheree-dimensional motion analysis(3-D motion analysis) method for the quantifyingthe pivot shift test.Methods：12patients from the Hospital of National Sports Medicine Institutionwere involved in the test. All tests were taken before the operation, the pivot shift testwas done for bilateral knees to analyze the difference between the image analysis and3-D motion analysis method.The point perpendicular cast to he line connect theGerdy’s tubercle and the fibula head from lateral epicondyle t was noted, the distancefrom the noted point to the Gerdy’s tubercle was calculated as “b”. The numericaldifferential form the maximum b to the beginning b in the whole pivot shift wascalculated as “maximum amplitude of b”. If the result was positive, the numericaldifferential form the beginning to the end of the glide or clunk in the pivot shift testwas calculated as “positive amplitude of b”. The numerical differential form thebeginning of the glide or clunk to the beginning of pivot shift test was calculated as“positive beginning of b”.Results：In the3-D motion analysis method, the curve of b in whole pivot shifttest form the anterior cruciate ligament(ACL) injured knee and intact knee could besummarized as “Double-peak” and “Single-peak” curve respectively; Positiveamplitude of b shows good correlation with time of ACL hurt and pivot shift grad (r=0.65and r=0.61, respectively; both P＜0.05)；There was significantly larger lateraltranslation in the contra-lateral knees than those in the ACL deficient knees (n=12, p＜0.01), good correlation(r=0.65, p＜0.05) were shown at the same time. In theimage analysis method, the curve of b could not show the typic peak as the3-Dmotion analysis method in all tests; The positive amplitude of b and positivebeginning of b showed good correlation(r=0.77, p＜0.01). Quantify the pivot shifttest in grad showed(Mean±SD): Grad-Ⅰ(1.05±0.23mm), Grad-Ⅱ(1.44±0.41mm),Grad-Ⅲ(1.90±0.77mm) by positive amplitude of b use3-D motion analysis method;Grad-Ⅰ(9.12±3.85mm), Grad-Ⅱ(11.16±1.89mm), Grad-Ⅲ级(13.59±2.40mm) bymaximum amplitude of b of b use3-D motion analysis method; Grad-Ⅰ(4.80±4.26mm), Grad-Ⅱ (8.01±4.55mm), Grad-Ⅲ (4.03±2.91mm) by positiveamplitude of b use image analysis method.Conclusions：3-D motion analysis method could quantify the pivot shift test well,the positive amplitude of b is sensitive and exact as a indicator; Image analysismethod could show the trend of the curve during the pivot shift test roughly, but showless accurate result than3-D motion analysis method.