BONE SCREW
A bone screw includes a tubular body including a wall having a bone thread in at least a portion of an outer portion of the wall, an open first end and an open second end. A plurality of cutting teeth is provided at the open first end. An engagement structure is provided at the second end for engagement with a screwing-in tool. The wall in the vicinity of the plurality of cutting teeth is thicker in a radial direction than the wall adjacent to the plurality of cutting teeth.
1 . A bone screw comprising a tubular body comprising:
a wall having a bone thread in at least a portion of an outer portion of the wall, an open first end and an open second end;
a plurality of cutting teeth at the open first end; and
an engagement structure at the second end for engagement with a screwing-in tool.
2 . The bone screw according to claim 1 , wherein the plurality of cutting teeth extend coaxially to the central axis of the tubular body.
3 . The bone screw according to claim 1 , wherein the plurality of cutting teeth are configured to cut a hole when the tubular body is screwed into the bone.
4 . The bone screw according to claim 1 , wherein the plurality of cutting teeth have a substantially saw tooth shape.
5 . The bone screw according to claim 1 , wherein the plurality of cutting teeth form an edge of the open first end.
6 . The bone screw according to claim 1 , wherein the wall thickness of the tubular body is smaller than about 15% of the outer diameter of the tubular body.
7 . The bone screw according to claim 1 , wherein the engagement structure comprises a plurality of recesses extending from the open second end through the wall of the tubular body substantially coaxially to a central longitudinal axis of the tubular body.
8 . The bone screw according to claim 1 , wherein the engagement structure comprises a polygon or star-like recess extending from the open second end into the inner wall of the tubular body.
9 . The bone screw according to claim 1 , wherein the wall of the tubular body comprises a plurality of openings.
10 . The bone screw according to claim 1 , wherein the tubular body comprises a non threaded section.
11 . The bone screw according to claim 1 , wherein a guide wire is provided that is insertable into the tubular body for guiding the insertion of the bone screw.
12 . The bone screw according to claim 1 , wherein the tubular body is cylindrical.
13 . A bone screw comprising a tubular body comprising:
a wall having a bone thread in at least a portion of an outer portion of the wall, an open first end and an open second end;
a plurality of cutting teeth at the open first end; and
an engagement structure at the second end for engagement with a screwing-in tool, wherein the wall in the vicinity of the plurality of cutting teeth is thicker in a radial direction than the wall adjacent to the plurality of cutting teeth.
14 . The bone screw according to claim 13 , wherein the plurality of cutting teeth extend coaxially to the central axis of the tubular body.
15 . The bone screw according to claim 13 , wherein the plurality of cutting teeth are configured to cut a hole when the tubular body is screwed into the bone.
16 . The bone screw according to claim 13 , wherein the plurality of cutting teeth have a substantially saw tooth shape.
17 . The bone screw according to claim 13 , wherein the plurality of cutting teeth form an edge of the open first end.
18 . The bone screw according to claim 13 , wherein the wall thickness of the tubular body is smaller than about 15% of the outer diameter of the tubular body.
19 . The bone screw according to claim 13 , wherein the engagement structure comprises a plurality of recesses extending from the open second end through the wall of the tubular body substantially coaxially to a central longitudinal axis of the tubular body.
20 . The bone screw according to claim 13 , wherein the engagement structure comprises a polygon or star-like recess extending from the open second end into the inner wall of the tubular body.
21 . The bone screw according to claim 13 , wherein the wall of the tubular body comprises a plurality of openings.
22 . The bone screw according to claim 13 , wherein the tubular body comprises a non threaded section.
23 . The bone screw according to claim 13 , wherein a guide wire is provided that is insertable into the tubular body for guiding the insertion of the bone screw.
24 . The bone screw according to claim 13 , wherein the tubular body is cylindrical.
25 . The bone screw according to claim 13 , wherein the inner radius of the wall in the vicinity of the plurality of cutting teeth is smaller than the inner radius of the wall adjacent to the plurality of cutting teeth to form an enlarged space within the tubular body adjacent to the plurality of cutting teeth.
26 . A tool for inserting a bone screw, the bone screw comprising:
a tubular body having a bone thread in at least a portion of an outer wall, the tubular body having an open first end and an open second end;
wherein at the open first end a plurality of cutting teeth is provided,
wherein at the second end a structure for engagement with a screwing-in tool is provided, and
wherein each of the plurality of cutting teeth is thicker in a radial direction than to the wall of the tubular body;
wherein the tool comprises an engagement structure which engages the engagement structure of the bone screw and which is configured to guide a guide wire.
27 . The tool according to claim 26 , wherein the tool comprises a guide hole for guiding the guide wire therethrough.
28 . A method of screwing a bone screw into a bone, the bone screw comprising:
a wall having a bone thread in at least a portion of an outer portion of the wall, an open first end and an open second end;
a plurality of cutting teeth at the open first end; and
an engagement structure at the second end for engagement with a screwing-in tool,
wherein the wall in the vicinity of the plurality of cutting teeth is thicker in a radial direction than the wall adjacent to the plurality of cutting teeth,
the method comprising:
introducing the cutting teeth of the bone screw to a surface of the bone;
engaging the engagement structure with the screwing-in tool;
rotating the screwing-in tool to rotate the bone screw such that the plurality of cutting teeth cut into the bone to create a hole, and such that bone material separated from the bone enters the bone screw;
rotating the screwing-in tool to rotate the bone screw such that the bone thread engages edges of the hole to advance the bone screw into the bone.