The KOMPACT-P study: Knee Osteoarthritis Management with Physiotherapy informed by Acceptance and Commitment Therapy—Pilot study protocol

Introduction: Incidence of total knee arthroplasty (TKA) is projected to rise 276% in 2030, and psychological distress affects up to 42% of people with knee osteoarthritis undergoing TKA, with demonstrated detrimental effects on postoperative outcomes. Few studies have assessed psychological treatment in people awaiting TKA, and these have been psychologist-delivered treatments. No evidence exists regarding psychologically-informed interventions delivered by health professionals currently embedded in TKA clinical pathways. The primary aim of this pilot study is to explore the safety, acceptability and feasibility of the Knee Osteoarthritis Management with Physiotherapy informed by Acceptance and Commitment Therapy (KOMPACT) approach in people awaiting TKA. Methods and analysis: 51 community-dwelling adults scheduled for a primary TKA at two hospitals will be recruited to this pilot, mixed-methods, prospective randomised controlled trial with assessor blinding. Participants will be randomised in a 1:2 ratio to either usual care (education class) or usual care plus KOMPACT (2 hours 20 min of preoperative physiotherapy informed by Acceptance and Commitment Therapy). Our primary outcome measures are safety (length of stay, complications and psychological health after KOMPACT), acceptability (treatment credibility and qualitative data) and feasibility (recruitment, retention and intervention fidelity) of the KOMPACT approach. Secondary outcomes include health service outcomes, patient-reported physical and psychological outcomes, and physical performance measures. Quantitative data collection was conducted at baseline, 1–2 weeks before TKA, 6 weeks after TKA and 6 months after TKA. Qualitative data collection is 1–2 weeks before TKA. Data analysis will take a quantitative-led approach with triangulation after thematic analysis of the qualitative data. Ethics and dissemination: This study has full ethics approval (HREC/18/WMEAD/440). Results from this study will be published in peer-reviewed journals and presented at local and international conferences. Trial registration number: Australia New Zealand Clinical Trials Registry (ACTRN12618001867280p)