Responsiveness of a Persian version of Knee Injury and Osteoarthritis Outcome Score and Tegner activity scale in athletes with anterior cruciate ligament reconstruction following physiotherapy treatment.

To evaluate the responsiveness and determine the minimal clinically important changes (MCICs), anchored by the patient response to a 7-point global rating scale, for Knee Injury and Osteoarthritis Outcome Score (KOOS), and Tegner activity scale in athletes undergoing physiotherapy treatment after anterior cruciate ligament reconstruction (ACL-R). Methods: Fifty-four patients undergoing physiotherapy completed the Persian versions of KOOS and Tegner scales at weeks 6 and 10 post ACL-R. The 7-point global rating of change was also completed at week 10. Responsiveness was calculated via receiver operating characteristic curve and correlation analysis. Results: Acceptable responsiveness was reached by the KOOS sports and recreation subscale (Sport/Rec) (area under the curve (AUC) = 0.72; Gamma = 0.37) and Tegner scale (AUC = 0.75; Gamma = 0.59). The MCIC scores of KOOS subscales and Tegner scale were reported. Conclusion: Our findings demonstrated that the KOOS Sport/Rec subscale and Tegner scale have adequate responsiveness between weeks 6 and 10 of physiotherapy. Therefore, these scales should be used to evaluate the effects of physiotherapy treatment and the changes in activity levels in this population. The MCIC scores of the KOOS and Tegner scale can be used to detect changes significant to the patient while avoiding limitations of other methods.