Abstract
Recently, a dynamic flat panel detector (FPD) system is appeared as a new digital X-ray modality, and makes it possible to provide dynamic X-ray images for a screening examination of knee function. Knee joint incongruity and osteoarthritis may be diagnosed as the screening examination. We developed a computer analysis method for knee joint movement with using the dynamic FPD. On lateral view of knee joint X-ray images, a movement of the lateral condyle of femur during flexion and extension movement is important in clinical practice, and a relationship between the movement of the lateral condyle of femur and knee joint angles during the movement is also important. We obtained 30 images of five healthy volunteers at 10 seconds during the knee-bending movement. An outline of the lateral condyle of femur were enhanced by the Sobel operator, which selected edge gradients within a limited range of orientations, and then detected by Binarization and the Template matching technique. The knee joint angles were automatically calculated by techniques such as the Sobel operator, and the Hough transform. It concludes that a possibility of computer analysis for a knee joint movement with the dynamic FPD as a new examination was indicated.
