This invention relates to a method and grading system for diagnosing the extent of degeneration of a knee joint, and determining a suitable surgical procedure for use in knee arthroplasty as indicated by the extent of joint degeneration. The method of determining a corrective surgical procedure for the treatment of degeneration of a joint includes the steps of comparing a set of radiological images, and in particular a set of x-ray images of the joint, to a set of degenerative joint conditions to determine a diagnosis； and correlating the diagnosis with a grading system which prescribes a corrective surgical procedure. The prescribed procedure may be a total knee arthroplasty, a partial knee arthroplasty, a patellofemoral arthroplasty or an anterior cruciate ligament reconstruction.
