Design and development of a mobile health intervention for rehabilitation support after knee arthroplasty: TeleRehabilitation after knee ArThroplasty (TReAT) project.

Background: The steep increase in knee arthroplasties in lower- and middle-income countries has increased demand for personalised rehabilitation care. Technology-based rehabilitation programs offer potential to replace or augment conventional face-to-face rehabilitation for providing continuum of care. We aimed to systematically develop a theory, evidence-driven, contextualised, and user-centred mobile health platform for people undergoing knee arthroplasty to facilitate monitoring progress during rehabilitation.

Methods: We followed the UK Medical Research Council's framework and adopted a behaviour design thinking approach, consisting of five steps; (1) conduct multiple literature reviews and cross-sectional surveys to determine the needs and problems experienced during the rehabilitation phase by healthcare professionals and individuals with replaced knees, (2) identify target behaviours along with barriers and facilitators, integrated within the Capability, Opportunity, Motivation-Behaviour (COM-B) framework, (3) identify intervention functions and components, behaviour change techniques, and features for the mobile application, selected after discussions with orthopaedic surgeons, physiotherapists and behavioural experts, (4) develop a prototype application for end-users, and a web-based platform for healthcare professionals, and (5) pilot test the intervention for end-users' feedback on usability of the application and to identify possible strategies for implementing the intervention package.

Results: Using the COM-B model, education, training, persuasion, enablement, and modelling were chosen as intervention functions for improving adherence to exercise protocol during early-phase of rehabilitation. The application featured five interlinked components; education, training, goal setting and self-management, communication, and a personalized therapy plan utilising 13 behaviour change techniques. An education booklet, exercise videos, text messaging, video consultation, and a digital tool for measuring range of motion were incorporated into the application. Feedback on the interactive prototype and education material was sought from ten patient volunteers and a physiotherapist. Pilot testing in a convenient sample with broad eligibility criteria (n = 30) indicated importance of digital literacy and dedicated time for remote consultation by healthcare provider within the existing clinical work. Overall, the intervention was well received and valued by the end users.

Conclusion: This paper demonstrates the development of a contextualised digital behavioural intervention grounded in behavioural theory and evidence from literature to improve end-user's engagement with rehabilitation protocols after knee arthroplasty in lower- and middle-income country context.

Trial registration: Study registered prospectively (on 16 February 2023) at Clinical Trials Registry of India (CTRI/2023/02/049792).