Endo-distractor

Abstract

The invention relates to a device for the distraction of bones or bone segments. The device comprises an anchoring screw having a longitudinal axis, a screw tip, a screw end for rotatably driving the anchoring screw, a threaded shank which adjoins the screw tip and has a screw thread, and a screw shank adjoining the screw end; and a distraction sleeve axially displaceable on the screw shank including a rear end, a front end, a through-bore extending coaxially therebetween, an external thread adjoining the front end, and a coupler portion formed in the rear end for receiving a driving tool. The anchoring screw comprises a collar positioned between the threaded shank and the screw shank that radially projects at least from the screw shank and which serves as an axial stop for the front end of the distraction sleeve when the distraction sleeve is positioned over the screw shank. The through-bore has a boring section with an enlarged cross-section which adjoins the rear end provided with a lateral surface and a seal ring coaxially arranged between the lateral surface and the screw shank.

1 - 62 . (canceled) 
   
   
       63 . A method for the distraction of a second bone segment with respect to a first bone segment through the use of a distraction device, comprising:
 forming a rotatable threaded connection between an anchoring screw of the distraction device and the second bone segment for distraction travel of the second bone segment along the threaded connection during a distraction procedure;   mounting a distraction sleeve of the distraction device in the first bone segment such that a shank of the anchoring screw extends through a throughbore of the distraction sleeve with a collar of the distraction sleeve bearing against a front end of the distraction sleeve; and   rotating the anchoring screw to cause the second bone segment to perform a screw-like displacement away from the first bone segment along a longitudinal axis of the of the anchoring screw.   
   
   
       64 . The method of  claim 63  wherein the step of mounting the distraction sleeve includes the forming of a connection between the distraction sleeve and the first bone segment that is non-rotatable while the anchoring screw is rotated for second bone segment distraction. 
   
   
       65 . The method of  claim 64  wherein the forming of the connection includes threading the distraction sleeve into the first bone segment. 
   
   
       66 . The method of  claim 65  wherein the threading of the distraction sleeve is performed by a driving tool. 
   
   
       67 . The method of  claim 63  wherein the step of rotating the anchoring screw to cause the displacement of the second bone segment is performed as a spaced series of incremental rotations over a period of time causing stepwise displacement to result in a total desired degree of displacement. 
   
   
       68 . The method of  claim 67  further comprising the step of maintaining a cover on a second end of the distraction sleeve between the incremental rotations. 
   
   
       69 . A method for effecting distraction of a second bone segment with respect to a first bone segment, comprising:
 forming a threaded bore in the second bone segment;   engaging a threaded anchoring screw with the threaded bore to form a rotatable threaded connection therebetween;   providing a bearing surface for the anchoring screw in the first bone segment; and   rotating the anchoring screw to cause distraction travel of the second bone segment along the anchoring screw and away from the first bone segment.   
   
   
       70 . The method of  claim 69  wherein the step of providing a bearing surface includes the step of mounting a distraction sleeve in the first bone segment. 
   
   
       71 . The method of  claim 70  wherein the step of providing a bearing surface comprises forming a conical surface at an intermediate location along a length of the anchoring screw and an engaging front end of the distraction sleeve. 
   
   
       72 . The method of  claim 70  wherein the mounting of the distraction sleeve is performed by threaded engagement between the distraction sleeve and first bone segment. 
   
   
       73 . A method for effecting distraction of a second bone segment with respect to a first bone segment comprising:
 forming aligned passageways through the first and second bone segments along a line of intended distraction;   passing a threaded anchoring screw through the passageway in the first bone segment and engaging a forward portion of the threaded anchoring screw with the passageway in the second bone segment to form a rotatable threaded connection between the anchoring screw and second bone segment;   providing a bearing surface for the anchoring screw in the first bone segment; and   rotating the anchoring screw to cause distraction travel of the second bone segment along the anchoring screw and away from the first bone segment.   
   
   
       74 . The method of  claim 73  wherein the passageway in the first bone segment is of a greater diameter than the passageway in the second bone segment, and the step of providing a bearing surface for the anchoring screw comprises the insertion of a distraction sleeve in the passageway in the first bone segment. 
   
   
       75 . The method of  claim 73  wherein the step of inserting the distraction sleeve includes forming a connection between the distraction sleeve and first bone segment that is non-movable during distraction travel of the second bone segment. 
   
   
       76 . The method of  claim 75  wherein the connection is a threaded connection.