Replacing Sedentary Time using an Innovative mHealth Intervention among Total Knee Replacement Patients

The number of individuals undergoing total knee replacement (TKR) each year continues to rise. While TKR is effective for improving pain and function, subsequent improvements in physical activity are not common. As a result, patients spend most of their day engaged in sedentary behavior, which may put them at higher risk of experiencing poor function and disability, as well as lower the overall success of the surgical treatment. Intervening on sedentary time may be a more feasible first-step approach for modifying activity-related behaviors in this population. Therefore, the purpose of this innovative clinical trial is to use TKR as a teachable moment for implementing a sedentary reduction intervention. We propose to use a remotely delivered mobile health (mHealth) intervention to reduce sedentary time among TKR patients. Patients (n=80) scheduled for TKR will be recruited to participate prior to surgery and then randomized at 4 weeks after surgery to either (1) NEAT!2 or (2) Control. NEAT!2 participants will use the NEAT!2 (Non-Exercise Activity Thermogenesis version 2) app until 3 months after surgery. The NEAT!2 app is designed to interrupt prolonged bouts of sitting by providing discrete reminders on the smartphone lock screen based on objectively measured activity. Further, NEAT!2 has been adapted based on TKA patient input and program preference. NEAT!2 participants will receive monthly coaching calls. Control participants will receive an education control app and receive non-intervention calls to assess general recovery. Data collection will occur pre-operatively, as well as at 3- and 6 months after surgery. The primary aim is to examine the acceptability and safety of the 8-week NEAT!2 intervention. Secondary aims include examining the preliminary effectiveness of NEAT!2 to reduce sedentary time, and influence physical function, physical activity, pain and stiffness. The proposed study will establish the acceptability of the innovative approach of decreasing sedentary time prior to targeting physical activity in adults undergoing TKR and examine the preliminary effectiveness of a remotely-delivered, mHealth sedentary reduction intervention to decrease sedentary time and improve physical function. is innovative for integrating a technology-based approach to reduce sedentary time during a “teachable moment” for TKR patients. The results of this study will build on our previous and current work to improve health behaviors after TKA and help to identify potentially effective and scalable strategies to improve long-term physical activity behaviors and physical function in patients after TKR.