Patent ID: 7850699
Filing Date: 2010-12-14
Classification: A61B

Abstract:
1. A combination of a fixation means for fixation of bone fragments at bone fractures and an extraction device for extracting the fixation means, the extraction device being removably connected to said fixation means, the fixation means comprising a sleeve and at least one pin provided in said sleeve, the extraction device comprising an inner extraction member removably connected to the pin of the fixation means, an outer extraction member removably connected to the sleeve of the fixation means, and an extraction handle that rotates relative to the outer and inner extraction members in order to extract the pin in a direction of extraction relative to the outer extraction member and the sleeve, the direction of extraction extending along a longitudinal axis of the outer extraction member, the inner extraction member being inserted into the outer extraction member and being axially movable relative to the outer extraction member, the outer extraction member being manually holdable in order to prevent the outer extraction member from rotating when the extraction handle is rotated, the outer and inner extraction members being respectively provided with rotary preventing members that directly engage one another in order to prevent the inner extraction member from rotating relative to the outer extraction member during extraction of the pin, the rotary preventing members of the outer extraction member being non-circular cross-sectional parts of a through hole in the outer extraction member, the rotary preventing members of the inner extraction member being non-circular cross-sectional parts, the rotary preventing members of the outer extraction member are provided in a rear end portion of the outer extraction member, the rotary preventing members of the inner extraction member are provided on a rear end portion of the inner extraction member, the lengths of the inner and outer extraction members and the location and shape of the rotary preventing members are chosen such that the extraction handle can cooperate with the inner extraction member in order to draw the inner extraction member backwards in the direction of extraction when the inner extraction member is inserted into the outer extraction member so that the rotary preventing members directly engage one another, and wherein a front end portion of the inner extraction member has a hole with inner threads which mesh with outer threads of the pin, and the hole of the inner extraction member has an inlet without threads, the inlet tapering conically in a direction inwards into the hole.