(A) Preoperative CT scan showing lateral depression of the tibial plateau and medial joint arthritic changes. (B) Intra-articular photo after proximal tibial cut. Lateral depressed articular surface with remaining cartilage covering. (C) Peripheral bone defect after removal of the depressed articular cartilage. (D) Postoperative X-ray with a stem added to the tibial tray and cement filling of the lateral defect.