A distal cut guide assembly including an intramedullary rod, an alignment guide extending from the rod at an angle and having a slot, a cut guide body having a rail defining a rail axis, a coupling member slidably coupled to rail, and a handle slidably and pivotally joining coupling member to slot and defining a handle axis. The position of the guide body being adjustable relative to the bone along rail axis and slot and about handle axis. A tibial cut guide assembly including a cut guide support member and a cut guide pivotally attached to the support member. An arthroplastic spacer including a spacer block having an axis of symmetry. The spacer includes a handle having a linear portion aligned with and longitudinally bisected by the axis of symmetry and a curved portion coupling linear portion to block. The curved portion is spaced from the axis of symmetry.