A miller assembly for creating a cavity in a bone. The cavity has a cross section which has a generally triangular profile having a first side generally parallel with an axis of the bone and a second side forming an acute angle with the first side, and is contiguous with a pre-existing conical cavity in the bone. The miller assembly includes a cutter and a frame for carrying the cutter. The frame includes a connection portion having a longitudinal axis and a cutter mount for mounting the cutter at a first angle approximating the acute angle with respect to the longitudinal axis of the connection portion. The cutter mount extends at the first angle from the longitudinal axis of the connection portion and is configured to receive a portion of the cutter and maintain the received cutter oriented at the first angle during rotation. The frame further includes a handle configured to form a portion of a drive joint for coupling the frame to a drill, the handle having a longitudinal axis. The longitudinal axis of the handle is coincident with the longitudinal axis of the frame.