Drill guide for installing a bone plate

An apparatus for guiding medical instruments used in attaching an occipital bone plate, the apparatus comprising:

• a handle assembly including an actuation member, a first elongate member, and a second elongate member, the actuation member operatively coupled with the first elongate member and configured to control movement of the first elongate member relative to the second elongate member;
• a guide member extending from the handle assembly, wherein the guide member has a first end, a second end, and a lumen extending therethrough from the first end to the second end;
• a spacer operatively coupled with the second elongate member of the handle assembly and adjustably positionable at the first end of the guide member, wherein the spacer is pivotable between a first position and a second position;
• and
• a locking mechanism configured to lock the spacer in either the first position or the second position;
• wherein actuation of the actuation member actuates the spacer between the first position and the second position.

A method of adjusting a drill depth, the method comprising:

• positioning a guide member with a handle assembly extending therefrom adjacent a bone, wherein the guide member has a lumen extending therethrough from a first end of the guide member to second end of the guide member;
• positioning a spacer operatively coupled to the guide member in a first position adjacent the first end of the guide member, the spacer including a hole therethrough in alignment with the lumen through the guide member;
• and
• actuating the spacer to a second position while the spacer remains operatively coupled to the guide member, wherein the opening of the spacer is not aligned with the lumen through the guide member in the second position.