Assessing the knee flexion range of motion after total knee arthroplasty: Technology versus senses

Following total knee arthroplasty surgery, attention should be paid to post-operative knee range of motion to achieve daily activities. Goniometer assessment is widely used to assess the range of motion in the post-operative period. This study aimed to determine the inter-rater ability of a smartphone application and visual estimation of the knee joint after total knee arthroplasty among different professions that commonly work together and compare whether any method is superior to another. Range of motion measurements was performed by four clinicians as two physiotherapists and two orthopedic fellows. They utilized the Goniometer Reports application for smartphones, universal goniometer, and visual estimation to measure angles of knees which was operated. A two-way mixed model of intra-class correlation coefficient (ICC) with a 95% confidence level was used to assess inter-rater reliability. Thirteen patients (11 female) and 20 knees (10 right) were assessed. The ICCs were found excellent both for between methods and between raters. Our results show that technology seems a more accurate way to determine the knee range of motion after knee arthroplasty compared to senses. However, in lack of technological resources or time, or to avoid possible infection, visual estimation also could provide useful information.