SYSTEM, INCLUDING A BENDING BAR AND A BENDING CAGE, FOR BENDING A PLATE IN A PLANE OF THE PLATE

摘要

A system and method for bending a bone fixation plate in the horizontal plane of the plate. The apparatus and method provide for optimization of applied bending moments by controlling the orientation of a bending tool to prevent deviation from an axis of bending. The system includes a bending bar or bars with an aperture or slot for engaging a plate or rod and a bending cage that can be in the shape of a rectangular box having a front surface separated from a rear surface by a distance. The front surface has a front elongate opening and the rear surface has a rear elongate opening. The front and rear openings are each formed by two parallel edges separated by a vertical distance and having a horizontal length. The relative dimensions of the respective bending bars and openings are such that the bending cage can be used to permit free movement of the bending bars in a direction parallel to the primary axis of the elongate openings but to prevent rotational movement of the bending bars about an axis substantially parallel to the length of the bending bars.

主权项

1. A system for bending a plate or rod, comprising
(a) at least a first elongate bending bar comprising first and second ends and a body portion between the first and second ends, the first elongate bending bar having a longitudinal axis, the body portion comprising an upper surface and a lower surface defining a thickness t, the first end comprising an aperture or slot for engaging the plate or rod such that, with the plate or rod engaged in the aperture or slot, a bending force can be applied to the plate or rod by application of force to the second end of the first elongate bending bar; and (b) a bending cage comprising a hollow interior and opposed front and rear surfaces separated by a distance d, each of the opposed front and rear surfaces defining an elongate opening formed with respective upper and lower parallel edges, each of the respective openings having a primary axis along a length thereof, respective dimensions of the respective openings, the distance d and the first elongate bending bar being such that (i) the first elongate bending bar is insertable through one of the respective openings in the front or rear surface to an operable position wherein the body portion of the first elongate bending bar is disposed within the bending cage with the first and second ends of the first elongate bending bar disposed outside of the bending cage at opposing sides of the bending cage, and (ii) with the first elongate bending bar in said operable position, the respective upper and lower parallel edges of the openings are disposed with respect to the upper and lower surfaces of the first bending bar so as to permit lateral movement of the first bending bar in a direction parallel to the primary axes of the respective openings but to restrict rotational movement of the bending bar about an axis substantially parallel to the longitudinal axis of the bending bar whereby, with the first bending bar in the operable position in the bending cage and the plate or rod engaged in the aperture or slot in the first end of the first bending bar, the bending cage restricts transfer of bending forces applied to the plate or rod by application of force to the second end of the first bending bar to an axis that is parallel to the primary axes of the respective openings.