| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a screw for bone fixation which can be driven in easily by a low push load without breakage or deformation of a tip portion of a shaft part. <P>SOLUTION: This screw 10 for bone fixation includes a head part 20 wherein a tool can be fitted and the shaft part 30 which projects from the center of the back of the head part 20. The tip 31 of the shaft part 30 is sharp and a helical thread 35 is formed toward the base 32 side of the shaft part 30 from the tip 31 thereof. The helical thread 35 has a first thread 37 which is formed axially in a prescribed length toward the base 32 side from the tip 31 of the shaft part 30, and a second thread 39 which is formed axially in a shorter length than that of the first thread 37 toward the base 32 side from the tip 31 of the shaft part 30 and in such a manner that it is disposed between the pitches of the first thread 37 at least in the tip portion 33. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
