| 摘要 |
A bone compression plate is provided with several sliding slits for countersunk bone screws having ball heads in the longitudinal dimension of the plate. Each sliding slit is countersunk in its end area opposite the fracture, the depth of which countersinking in the plate determines the final axial position of the screwhead. That depth is greater than that of the rest of the sliding slit. The bearing surface of the countersinking for the screwhead extends over an area which is included within an angle of more than 180 DEG . It is thus possible, on the one hand, to move the plate with respect to the pieces of fractured bone to obtain a pressing together of the two pieces of bone when the bone screw has not been screwed tight. On the other hand, it is possible to fasten the plate immovably to one piece of the fractured bone by inserting a bone screw into the countersink slit. Pressing of the pieces of bone fragment together can be accomplished automatically by means of chamfering provided on the ball head of the countersunk bone screw in the area at the opposite end of the sliding slit. Deeper countersinking provided in the end area containing the original countersunk depression makes possible the positioning of the countersunk bone screw at an oblique angle.
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