A method and system for femoral condylar resection arthroplasty of the knee, which preserves the undamaged meniscus, whether by arthroscopy or arthrotomy, and only replaces the damaged area of the femoral condyle. In one embodiment, only the distal femoral condyle is replaced and the posterior femoral condyle remains intact. In another embodiment, both the distal and posterior femoral condyle are replaced. The method and system include placing an intercondylar insert between articular surfaces of a distal femoral condyle and a tibial plateau with the knee in extension. The method and system also includes a box retractor having four right angle blades, two for medial structures and two for lateral structures. The blades are at two depths, shallow and deep. The components of the system are preferably of plastic material. The method and system preserve the meniscus on top of the tibial plateau.