Abstract: A burr guide assembly is described for guiding a burr tool during a procedure wherein the burr tool is used to cut a bone. The guide assembly includes a housing which is configured to be attached to the bone, a guide sleeve attached to the housing such that the guide sleeve can freely pivot about a pivot axis within a defined range, and a burr tool. The guide sleeve has a bore that extends along its length, which is located eccentrically within the guide sleeve. The burr tool has a cutting portion that is configured to be at least partially disposed within the bore. The guide sleeve is mounted within the housing such that the cutting portion is substantially restricted to movement in a plane that is perpendicular to the pivot axis.