Osteotomy plate, plate driver and method for their use
An orthopedic plate is specifically configured for use in osteotomies, in which part of the plate extends into a portion of a first bone segment and part is external to the cortical surface of an adjacent bone segment to fix the segments to allow them to fuse. The plate has a first end and a second end where the end which is inserted into the bone has a chamfer and a through hole having a hole axis optionally at an oblique angle to the longitudinal axis of the plate, and which can receive a screw, peg or pin. The second end of the plate includes a locking screw hole and optionally including a compression slot extending in a direction toward a screw hole in the opposing end. Optionally, the non-locking hole has a shroud that forms an arc or portion of a cylinder over the hole. A plate driver having a recess that holds the plate is used to insert the plate into the bone.
1. A plate for bone fixation comprising:
a first end;
a second end with a deep chamfer which tapers from a lateral edge of the plate;
a bottom surface configured for contact with a bone;
a top surface spaced-apart from the bottom surface, wherein an open-ended passageway communicates between the top surface and the bottom surface, the open-ended passageway being defined in offset relation to at least one of the top surface and the bottom surface, with a portion of the top surface circumferentially adjacent a top open-end of the passageway that is configured to receive a head of a screw within an angle of rotation of up to 20°; and
a shroud extending outward from the top surface at an oblique angle and covering at least a portion of the top open-end, the shroud adapted to be interposed between a tissue and the head of the screw so as to prevent tissue irritation and provide compression to the bone.
2. The plate of claim 1 , wherein the plate has a distal edge having a larger thickness to provide a broader shoulder so as to allow for the proximal portion of the plate to be driven into a bone.
3. The plate of claim 1 , further comprising a compression slot passageway communicating between the top surface to the bottom surface.
4. The plate of claim 1 , wherein an axis of the passageway forms an angle of between 10° and 45° with the top surface.
5. The plate of claim 1 , wherein an axis of the passageway forms an angle of between 15° and 40° with the top surface.
6. The plate of claim 1 , wherein an axis of the passageway forms an angle of between 25° and 35° with the top surface.
7. The plate of claim 1 , wherein a cutting edge is formed at the first end.
8. A plate for bone fixation comprising:
a bottom surface configured for contact with a bone;
a top surface arranged in spaced-relation to the bottom surface, wherein an open-ended passageway is defined between the top surface and the bottom surface sized to permit a screw to be inserted therethrough with a less than 90° angle between a screw axis and a passageway axis to allow for a conical rotation of the screw, the passageway configured to receive a head of the screw wherein the passageway axis forms an angle with respect to the bottom surface between 10° and 45°; and
an arcuate shroud projecting outwardly from the top surface at an oblique angle and covering at least a portion of an open-end of the passageway, the shroud adapted to be interposed between a tissue and the head of the screw.
9. The plate of claim 8 , wherein the angle of the passageway axis with respect to the bottom surface is between 15° and 40°.
10. The plate of claim 8 , the angle of the passageway axis with respect to the bottom surface is between 25° and 35°.
11. The plate of claim 8 , further comprising a second open-ended passageway is defined through the plate that communicates between the top surface and the bottom surface.
12. The plate of claim 8 , further comprising a tapered crescent-shaped cutting edge.
13. A plate system for use in associated bone comprising:
a non-locking screw having distal threads and a head having a rounded surface without external threads; and
a plate having:
a first end and a second end with a longitudinal axis defined between the first end and the second end;
a bottom surface configured for contact with a bone;
a top surface spaced-apart from the bottom surface, wherein an open-ended passageway communicates between the top surface and the bottom surface, the open-ended passageway being defined in offset relation to at least one of the top surface and the bottom surface, with a portion of the top surface circumferentially adjacent a top open-end that is configured to receive the head of non-locking screw within an angle of rotation of up to 20°; and
a shroud projecting outwardly from the top surface at an oblique angle and covering at least a portion of the top open-end, the shroud adapted to minimize interaction between a tissue and the head of a non-locking screw.
14. The plate of claim 13 , wherein the plate has a distal edge having a larger thickness to provide a broader shoulder so as to allow for the proximal portion of the plate to be driven into a bone.
15. The plate of claim 13 , wherein the passageway is shaped so as to permit the screw to be inserted therethrough with an angle between a screw axis and a passageway axis of up to 20° of conical rotation.
16. The plate of claim 13 , wherein an axis of the passageway forms an angle of between 10° and 45° with the top surface.
17. The plate of claim 13 , wherein an axis of the passageway forms an angle of between 25° and 35° with the top surface.
18. The plate of claim 13 , wherein a straight taper cutting edge is formed at the first end.