Background <p>TRAK MSK is a co-designed digital physiotherapy supported self-management programme. It enables people to develop the knowledge, confidence and skills to self-manage their condition and pain, to improve everyday function and physical activity levels. We explored the feasibility of conducting a definitive trial of the TRAK MSK intervention.</p> Methods <p>We conducted a two-arm multi-site randomised external feasibility trial with an embedded process evaluation. We recruited adults aged 18 and over with self-reported activity related joint pain for at least 3&#xa0;months, attending physiotherapy clinics. Participants were randomised to either the TRAK MSK intervention or usual NHS physiotherapy care. The TRAK MSK intervention was delivered over 16&#xa0;weeks and included up to five online coaching consultations with a physiotherapist trained in self-management support, and access to a website designed to support these consultations. Primary feasibility outcomes were recruitment, randomisation and retention at 16&#xa0;weeks post-randomisation, all of which were pre-defined. Secondary outcomes were feasibility of collecting health services resource use and intervention costs and reported variability of participant rated questionnaires at baseline and follow up. We evaluated acceptability of intervention receipt and trial processes and intervention fidelity with an embedded process evaluation.</p> Results <p>We consented 87 (59%) eligible participants from 147 that expressed an interest in taking part. Participants needed to complete baseline outcome measures to progress to randomisation. Seventy-five individuals (86% of those consented and 51% of those who expressed interest), were randomised and received TRAK MSK intervention (<i>n</i> = 37) or usual care (<i>n</i> = 38); 12 consented participants did not complete their baseline outcome measures and were not randomised. After 16&#xa0;weeks, 23 participants from TRAK MSK and 22 participants from usual care completed the participant rated questionnaires (60%). Interviews with participants and physiotherapists suggested the intervention was acceptable and had a place in future ways of working. Outcomes reflecting self-rated pain, physical activity, confidence in managing pain and health related quality of life were in the anticipated direction and aligned to the TRAK MSK programme theory.</p> Conclusion <p>Progression to a full trial is recommended based on feasibility and acceptability with modifications, such as using multiple recruitment strategies and initial in person visit. The definitive trial design will be informed by the findings of this study and stakeholder engagement. Physiotherapist training for self-management support should include components that build the skills to integrate patient digital health literacy coaching into TRAK MSK.</p> Trial registration <p>ISRCTN82011326. Registration date: 15/07/2022. Date of first participant enrolment 01/07/2022. This trial was retrospectively registered.</p>