Device for osteosysnthesis

A bone plate system, comprising:

• a bone plate having a bottom surface for contacting bone, an upper surface and at least one through hole extending from the bottom surface to the upper surface, the through hole having a central axis and a cross section that extends orthogonally to the central axis and is one of at least partially polygonal, at least partially prismatic, and at least partially elliptical;
• a bushing within the through hole, the bushing including a central bore designed to receive a bone fixation element, wherein a cross section of the bushing orthogonal to the longitudinal axis of the bushing is shaped substantially the same as the cross section of the through hole so that the bushing is secured against rotation about its longitudinal axis;
• and
• at least one bone fixation element having a portion for anchoring within the bone, the at least one bone fixation element being configured and dimensioned for insertion into the central bore of the bushing.

A bone plate system, comprising:

• a bone plate having a lower surface for contacting bone, an upper surface and at least one through hole extending from the lower surface to the upper surface, the through hole having a central axis defining a vertical centerline and a cross-section extending orthogonally to the vertical centerline defined by two incomplete semicircles connected to each other by at least two non-circular cut outs forming grooves in the bone plate;
• at least one bushing insertable in the through hole, the bushing comprising:
• a top surface;
• a bottom surface;
• a longitudinal axis substantially perpendicular to the top and bottom surfaces of the bushing;
• a central bore designed to receive a bone screw;
• and
• a peripheral outside face having at least two outwardly extending protrusions defining an axis of rotation of the bushing extending through the protrusions;
• and
• at least one bone screw having a threaded shaft for anchoring within the bone, a longitudinal screw axis, and a screw head configured and dimensioned for insertion into the central bore of the bushing,
• wherein the bushing is configured and dimensioned to be radially compressible and radially expansible;
• and
• wherein a cross section of the bushing orthogonal to the longitudinal axis of the bushing is shaped substantially the same as the cross section of the through hole such that when the bushing is inserted into the through hole, the bushing is pivotable about the axis of rotation defined by the protrusions.