IKDC or KOOS? Which measures symptoms and disabilities most important to postoperative articular cartilage repair patients?

Background: The relevance of knee-specific subjective measures of outcome to patients has not been evaluated for cartilage repair procedures. Purpose: The aim of this study was to identify which instrument out of the Knee injury Osteoarthritis Outcome Score and the International Knee Documentation Committee Subjective Knee Form measures symptoms and disabilities most important to postoperative articular cartilage repair patients. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Data were collected from 58 participants of an Internet knee forum via a self-reported online questionnaire consisting of demographic and surgical data, the Tegner activity scale, and 49 consolidated items from the Knee injury Osteoarthritis Outcome Score and the International Knee Documentation Committee Subjective Knee Form. Item importance, frequency, and frequency-importance product were calculated. Results: Overall, the International Knee Documentation Committee Subjective Knee Form was the highest scoring instrument in all categories. However, 2 of the Knee injury Osteoarthritis Outcome Score subscales (function in sport and recreation and knee-related quality of life) scored higher on mean importance and frequency-importance product than the overall International Knee Documentation Committee Subjective Knee Form score. Conclusion: The International Knee Documentation Committee Subjective Knee Form provided the best overall measure of symptoms and disabilities that are most important to this population of postoperative articular cartilage repair patients. This brings into question the validity of using the Knee injury Osteoarthritis Outcome Score in shorter-term - less than 10 years - studies. Issues related to sports activity appear to be highly valued and very pertinent to evaluation of outcomes for this patient group.