Background: The aim of this study is to validate the Knee Osteoarthritis Grading System (KOGS) of progressive osteoarthritic degeneration for the tri-compartmental knee. This system defines the site and severity of osteoarthritis to determine a specific knee arthroplasty.
Methods: The radiographic sequence for KOGS includes standing coronal (anteroposterior), lateral, 30° skyline patella, 15° and 45° Rosenberg and stress views in 20° of flexion.