VARIABLE ANGLE CANNULATED BONE SCREW AND METHODS FOR USE THEREOF

1 . A bone screw comprising:

An elongated shaft including a proximal end, a distal end, a leading portion, and a trailing portion;

a cannula bored completely through said elongated shaft extending from said distal end to said proximal end, the cannula aligned with said shaft;

the leading portion having at least one thread; and

the trailing portion comprising an externally threaded head adapted to engage a threaded hole.

2 . The bone screw of claim 1 wherein said externally threaded head is tapered.

3 . The bone screw of claim 1 wherein said cannula is adapted to receive a K-wire therethrough.

4 . The bone screw of claim 1 wherein said externally threaded head is adapted to engage said threaded hole at a range of angles selectable at the time of engagement.

5 . A method for attaching a bone plate having a threaded hole and a hole axis to a bone, using a bone screw having a cannulated shaft and an externally threaded head, the method comprising the steps of:

inserting a K-wire through the threaded hole and into the bone along an insertion axis not collinear with said hole axis;

drilling a cavity in the bone in alignment with the inserted K-wire by using a cannulated drill over the K-wire;

inserting the bone screw over the k-Wire and through the threaded hole by engaging the cannulated shaft of the bone screw with the K-wire;

advancing the bone screw over the K-wire until the leading end of the screw enters the drilled bone cavity;

driving the bone screw into the bone until the externally threaded head of the screw bone engages the threaded hole of the bone plate;

driving the threaded head of the bone screw into the threaded hole of the bone plate until it lockingly cross-threads; and

removing the k-Wire.

6 . The method of claim 5 wherein said insertion axis is selected at the time of insertion of the K-wire.