Patent ID: 7892207

Claim:
A surgical instrument set comprising: a cannula having a distal end, a proximal end, a passage therethrough, and a mid-longitudinal axis, said passage at said distal end having a reduced dimension transverse to the mid-longitudinal axis less than the maximum dimension of said passage transverse to the mid-longitudinal axis, said distal end having an outer perimeter converging at an angle toward the mid-longitudinal axis of said cannula, said distal end having an opening in communication with said reduced dimension of said passage, said distal end being sufficiently rigid to penetrate and displace bone during advancement of said distal end of said cannula into the bone, said outer perimeter of said distal end including a plurality of serrations that are adapted to cut into bone; and a stylet having a distal portion, a proximal portion, and a tapered transition portion proximate said distal portion, said tapered transition portion having an angle approximating the converging angle of said outer perimeter of said distal end of said cannula, said tapered transition portion having a length, said stylet being sized and configured to be inserted into said passage of said cannula, said distal portion of said stylet and at least a portion of said tapered transition portion both being configured to pass through said reduced dimension of said passage of said cannula and extend beyond said opening in said distal end of said cannula, said distal portion of said stylet having a tip and a length as measured from said tip to said tapered transition portion, said length being greater than the length of said transition portion.