Device for distracting or compressing bones on bone fragments

A system for applying axial forces on at least two bone fragments or vertebrae to which the system can be connected, comprising

• A) a first connecting element, with a first longitudinal axis, that can be connected to a bone fragment or a vertebral body, and
• B) a second longitudinal connecting element, with a second longitudinal axis, that can be connected to another bone fragment or vertebra, with the first and second longitudinal axes defining a plane while the second connecting element is movable relative to the first connecting element in a manner whereby the second longitudinal axis travels within the plane;
• wherein the system
• C) also includes, coaxially with the first longitudinal axis, a longitudinal support with a third longitudinal axis, a back end and a front end that can be connected to the first connecting element, with the third longitudinal axis extending parallel to the plane;
• D) includes a tubular sleeve that extends coaxially with the third longitudinal axis and is provided with a coaxial end-to-end bore within which the longitudinal support, featuring a forward end piece that faces the first connecting element as well as a rearward end piece, is movable parallel to the third longitudinal axis;
• E) comprises a first lever that connects the forward end piece to the second connecting element, that has a fourth longitudinal axis that extends essentially parallel to the plane and which is attached to the end piece in rotatable fashion, whereby the fourth longitudinal axis can be swiveled in a direction essentially parallel to the plane;
• also
• F) includes at least one second lever having a fifth longitudinal axis extending essentially parallel to the plane and which is pivotably attached to the first connecting element and to the second connecting element in a manner whereby the fifth longitudinal axis can be swiveled essentially parallel to the plane, so that
• G) a relative movement between the forward end piece and the first connecting element parallel to the third longitudinal axis produces a relative movement between the first and the second connecting element along a line that extends parallel to the plane and essentially in a transverse direction relative to the third longitudinal axis.