Interference screw and cannulated sheath for endosteal fixation of ligaments
AssigneeArthrex, Inc.
InventorReinhold Schmieding
Life of this patent
Estimating the term…
Abstract
An interference screw and a cannulated sheath for fixating ligaments. A graft, attached between previously cut bone blocks, is placed under tension in a graft tunnel. The sheath has a cutout at one end such that during screw insertion, the graft is covered by the sheath and protected from the threads of the screw, while the bone to which the graft is being fixed is exposed to the threads of the screw. The screw is driven between the bone to which the graft is being fixed and a corresponding one of the bone blocks. The screw may be cannulated for insertion over a pre-positioned guide pin.
Claims18
An apparatus for endosteal fixation of a substitute ligament by screw insertion, comprising:
- an interference screw;
- and
- a removable cylindrical cannulated sheath for receiving said interference screw, said sheath having a proximal end and a distal end, said distal end of said sheath having a cutout portion and a covered portion, said covered portion preventing said interference screw from damaging the substitute ligament during screw insertion, and said cutout portion exposing a portion of said interference screw to permit said interference screw to cut into a bone tunnel wall during screw insertion.
A method of endosteal fixation of a graft by screw insertion, comprising the steps of:
- drilling a graft tunnel through adjacent first and second bone masses;
- extending a graft attached between previously cut bone blocks under tension in said graft tunnel between said adjacent bone masses;
- positioning a cannulated sheath between said graft and said first bone mass, said cannulated sheath having a cutout at one end, said sheath being positioned such that said graft is covered by said sheath and said first bone mass is exposed by said cutout;
- inserting said interference screw in the cannula of said cannulated sheath;
- driving said interference screw between said first bone mass exposed by said cutout and a corresponding one of said bone blocks;
- and
- removing said cannulated sheath.
A method of endosteal fixation of a graft by screw insertion, comprising the steps of:
- drilling a graft tunnel through adjacent first and second bone masses;
- extending a graft attached between previously cut bone blocks under tension in said graft tunnel between said adjacent bone masses;
- positioning a guide pin between said graft tunnel at said first bone mass and a corresponding one of said bone blocks;
- placing a cannulated sheath over said guide pin, said guide pin guiding said sheath to a position between said graft and said first bone mass, said sheath having a cutout at one end, said sheath being positioned such that said graft is covered by said sheath and said first bone mass is exposed by said cutout;
- placing a cannulated interference screw over said guide pin, said guide pin guiding said screw as it is inserted through the cannula of said cannulated sheath to a position where said first bone mass is exposed by said cutout;
- driving said cannulated interference screw between said first bone mass exposed by said cutout and said corresponding bone block;
- and
- removing said cannulated sheath.
Dependencies are inferred from the claim text.