METHOD FOR DETERMINING AN ACETABULAR COMPONENT IMPLANTATION SITE WHEN PLANNING ENDOPROSTHESIS REPLACEMENT IN PATIENTS WITH HIP DYSPLASIA

摘要

FIELD: medicine.;SUBSTANCE: invention refers to medicine, namely to radiation diagnostics, traumatology and orthopedics, and can be used for determining the acetabular component implantation site when planning hip replacement in patients with hip dysplasia. Ancillary lines are used through anatomical landmarks on the anteroposterior radiograph of the hip joint, and points of their intersection. Lower medial point of the cotyloid cavity, the lateral point of the terminal line of the pelvis and the lateral point of the roof of the cotyloid cavity are used as anatomical landmarks. Thereafter, a medial limiting line is drawn through a lower medial point of the cotyloid cavity and a lateral point of the terminal line of the pelvis, to which a lower limiting line is drawn perpendicularly through the lower medial point. Ascending diagonal line is made upward and laterally in the form of a bisector from the angle formed by the intersection of these two lines. With participation of ascending diagonal line there is an upper restricting line oriented parallel to lower limiting line. Across the lateral point of the roof of the cotyloid cavity, a lateral limiting line is made parallel to the medial limiting line. Upper limiting line is drawn through the point of intersection of the ascending diagonal and lateral limiting lines, thereby forming a geometric figure in the form of a square. Place for implantation of acetabular component of a hip joint is determined as a cotyloid cavity area bounded by a square. At that, acetabular component inclination is defined parallel to ascending diagonal line. Center of the square is determined by the corresponding rotation center of the planned cotyloid component. If it is possible to identify the "tear" figure behind the lower medial point of the cotyloid cavity, a lower contour of the "tear" figure may be taken. If it is impossible to identify the figure of "tear" beyond the lower medial point of the cotyloid cavity, an upperlateral point of the pelvic opening can be taken.;EFFECT: more accurate determination of an area of the acetabular spherical component implantation by determining the optimal region on the x-ray image of the cotyloid cavity, in which it is possible to inscribe a maximum semicircular contour of a certainly oriented cotyloid component taking into account features of anatomy of the acetabulum in patients with hip dysplasia.;3 cl, 9 dwg, 1 ex