Abstract: The present disclosure relates to a rotation prevention member of a leg screw for fixing a bone that is configured to prevent rotation of a leg crew that is coupled to a nail in a medullary cavity such as a femur and fixes a fracture portion. The rotation prevention member of a leg screw for fixing a bone, in which a femoral nail is fitted in an end of a femoral marrow, a leg screw combined with a cap is laterally inserted in a transverse hole formed at an angle with respect to a longitudinal axis of the nail, and the leg screw is fixed to be longitudinally movable without rotating in the transverse hole, includes: pin guide grooves formed symmetric to each other in a longitudinal direction of the leg screw; a superelastic member inserted in the pin guide grooves; and a cap thread-fastened to a rear surface of the leg screw to prevent separation of the superelastic member in order to prevent rotation between a threaded portion of the leg screw and a bone due to rotation after a fracture part is occupied.

Abstract: The present disclosure relates to a surgical aiming device 1 that prevents a sleeve from being pushed backward or shaken when a drill or a leg screw is implanted after a guide sleeve is mounted on an aiming device. The surgical aiming device includes: a body 20 having an aiming arm 21 and a barrel 22; a guide sleeve 30 disposed at an end of the aiming arm 21 and guiding a nail 10 and a leg screw 12; and a knob 40 for detachably attaching the guide sleeve 30, in which the guide sleeve 30 can be detachably attached in a one-touch type by a guide sleeve attachment/detachment unit 100 installed at an end of the aiming arm. The guide sleeve attachment/detachment unit 100 includes: an operation unit 21a installed at an end of the aiming arm 21; a button 110 installed at the operation unit 21a and partially exposed to the outside; an operation lever 120 being rotated on a rotary shaft by operation of the button 110; and a threaded portion 30a controlled by the operation lever 120 and formed on the guide sleeve 30a.

Abstract: A bone plate system for fracture surgery is provided. The bone plate system includes a bone plate and a locking screw. The bone plate includes an upper surface, a lower surface facing a bone, and a locking hole in which an even-number-ridge internal thread is formed. The locking screw is coupled to the locking hole. The locking screw includes a head tapered so that a diameter thereof decreases along a center axis, a shank extending from the head, a double-ridge external thread formed on the head and configured to be tightened to the even-number-ridge internal thread, and an external thread formed on the shank and configured to be fastened to the bone.

Abstract: A bone plate system for fracture surgery is provided. The bone plate system includes a bone plate and a locking screw. The bone plate includes an upper surface, a lower surface facing a bone, and a locking hole in which an even-number-ridge internal thread is formed. The locking screw is coupled to the locking hole. The locking screw includes a head tapered so that a diameter thereof decreases along a center axis, a shank extending from the head, a double-ridge external thread formed on the head and configured to be tightened to the even-number-ridge internal thread, and an external thread formed on the shank and configured to be fastened to the bone.