Physiotherapists' Experiences and Perceived Acceptability of Delivering a Knee Bracing Intervention for People With Symptomatic Knee Osteoarthritis in a Randomised Trial (PROP OA): A Qualitative Study.

Objectives: To explore physiotherapists' experiences and perceived acceptability of delivering a bracing intervention for knee osteoarthritis (OA) in the 'PROvision of braces for Patients with knee OA' (PROP OA) randomised controlled trial.

Method: Semi-structured telephone interviews with consenting physiotherapists who received the PROP OA training programme and delivered the knee bracing intervention (advice, information and exercise instruction plus knee brace matched to patients' clinical and radiographic presentation and with adherence support). Interviews were recorded and transcribed verbatim. Two-stage analytic framework: inductive thematic analysis preceded mapping to constructs of the Theoretical Framework of Acceptability.

Results: Eight physiotherapists were interviewed and six key themes were developed. Perceptions of the training programme were generally positive, but additional formal training and experiential learning consolidated confidence and skills in novel intervention components. Advice, information, and exercise instruction reflected usual physiotherapy care for knee OA. Physiotherapists were confident in delivering the knee brace, but determining the pattern of knee OA to inform brace type selection was challenging. Physiotherapists valued brace adherence enhancing strategies and the follow-up appointment to facilitate adherence. Perceived impact of the bracing intervention for people with OA was positive. The bracing intervention was perceived as acceptable, although improving self-efficacy to deliver novel intervention components (e.g., reading x-rays) would enhance acceptability.

Conclusion: The complex knee bracing intervention was broadly perceived as acceptable by physiotherapists. If implemented within clinical practice beyond the trial, physiotherapists might benefit from not only initial training in brace selection but also ongoing support and mentoring to increase self-efficacy in delivery.