Reliability of the International Knee Documentation Committee Radiographic Grading System

BackgroundThe International Knee Documentation Committee (IKDC) forms are commonly used to measure outcomes after anterior cruciate ligament (ACL) reconstruction. The knee examination portion of the IKDC forms includes a radiographic grading system to grade degenerative changes. The interrater and intrarater reliability of this radiographic grading system remain unknown.HypothesisWe hypothesize that the IKDC radiographic grading system will have acceptable interrater and intrarater reliability.Study DesignCase series (diagnosis); Level of evidence, 4.MethodsRadiographs of 205 ACL-reconstructed knees were obtained at 5-year follow-up. Specifically, weightbearing posteroanterior radiographs of the operative knee in 35° to 45° of flexion and a lateral radiograph in 30° of flexion were used. The radiographs were independently graded by 2 sports medicine fellowship—trained orthopaedic surgeons using the IKDC 2000 standard instructions. One surgeon graded the same radiographs 6 months apart, blinded to patient ...