Responsiveness of Impairment-based Outcome Measures in Individuals With Anterior Cruciate Ligament Reconstruction Following Physiotherapy

 The primary purpose of physiotherapy in patients with Anterior Cruciate Ligament (ACL) reconstruction is to reduce pain, improve Range of Motion (ROM), muscle strength, and balance after surgery. Thus, therapists need outcome measurement tools with acceptable validity, reproducibility, and responsiveness to assess these changes after the intervention. This study investigates the responsiveness of the tools used to measure pain, ROM, knee muscle strength, and dynamic balance. We also want to determine minimal clinically significant change for these outcomes in patients with ACL reconstruction after physiotherapy.

The study participants were 54 young patients with ACL reconstruction evaluated using impairment-based outcome measures of visual analog scale, goniometer, hand-held dynamometer, and Star Excursion Balance Test (SEBT) at baseline (2 weeks after ACL reconstruction ) and 4 weeks after physiotherapy. At the second phase of evaluation, the participants also completed the 7-point global change rating scale. For assessing the responsiveness of the tools, we used the Receiver Operating Characteristics (ROC) curve and correlation analysis

 Analyzing the ROC curve showed that the knee extension ROM, quadriceps and hamstring strength, and medial and posteromedial directions under SEBT had acceptable responsiveness (>0.70). The Spearman correlation coefficient between the scores obtained for these outcomes and the score of 7-point global change rating scale were significant in the range of 0.36-0.51. For all the study outcome measurement tools, minimal significant clinical changes were reported.

 The results of this study support the responsiveness of goniometer for knee extension ROM, hand-held dynamometer for quadriceps and hamstring strength, and SEBT for dynamic balance at medial and posteromedial directions in the assessment of clinical changes in patients with ACL reconstruction. The reported minimal significant clinical changes for each tool can help the clinicians and researchers to decide on determining the actual significant change in the ACL patient’s clinical conditions after physiotherapy.