International Orthopaedics | 2021
Comment on article: The effect of immediate post-operative knee range of motion photographs on post-operative range of motion after total knee arthroplasty: An assessor-blinded randomized controlled clinical trial in sixty patients
Abstract
We read with deep interest the article “The effect of immediate post-operative knee range of motion photographs on post-operative range of motion after total knee arthroplasty: An assessor-blinded randomized controlled clinical trial in sixty patients” by Pinsornsak et al. The authors performed a randomized clinical trial on 60 patients who underwent primary total knee arthroplasty (TKA). The authors concluded that “Showing knee range of motion photographs seemed to result in significant improvement of knee flexion and clinical KSS in the first 6 weeks post-TKA and may be recommended as part of post-TKA rehabilitation.” The authors should be congratulated for performing this well-designed study. Although the study of Pinsornsak et al. was well conducted, there are some questions regarding the study that need to be clarified [1]. In the “Outcomemeasures” section, the authors stated that “The primary outcome was post-operative knee ROM measured in full passive flexion and extension using the long goniometer by two outcome assessors at day three, six weeks, three months, six months, one year, and two years post-TKA.” Although this was an assessor-blinded study, the authors did not mention whether the two evaluators of primary outcome were blinded to assessment. In the second paragraph of “Outcome measures” section, the authors stated that “The outcome assessors conducting these measurements were nurses trained in the same measurement method by a senior surgeon.” The Knee Society Pain Scores obtained by clinical nurses have been shown to be biased for analgesic studies, and this may have contributed for additional biases in the study results. Nor is it clear whether the scores at these points were repeatedly measured by two independent reviewers. Furthermore, as for the rehabilitation protocols, it is not clear how the physiotherapy in Pinsornsak et al. study was performed (e.g., the number of daily attempts, the level of assistance required to complete each task). We respectfully appreciate that Pinsornsak et al. provided us with an important study which can provide a guide for clinical decision-making. We would welcome some comments from the authors as this would help to further support the findings of this important study.