A SPINAL SCREW FOR THE OSTEOPOROTIC

摘要

PURPOSE: A pedicle screw is provided to be fixed to a backbone of an osteoporosis patient by increasing a contact dimension between a screw thread and a cancellous bone. CONSTITUTION: A head part(110) has a receiving groove and a female screw part. The receiving groove is formed into U shape in order to receive a rod. The female screw part is formed according to an inner circumference of the receiving groove. A screw part(120) includes a first core part(121), a second core part(123), a third core part(125), and a screw thread(127). The second core part is formed into a cylinder type. The first core part and the third core part are formed into a cone type. The screw thread is formed into a cylinder type according to outer diameters of the first core part and the second core part.