Effectiveness of a cognitive–behavioural group intervention for knee osteoarthritis pain: a randomized controlled trial

OBJECTIVE: To assess the effectiveness of a six week cognitive-behavioural group intervention in patients with knee osteoarthritis pain. DESIGN: Single-blinded randomized controlled trial. STUDY SETTING: Primary care providers in a medium-sized city in Finland. PATIENTS: A total of 111 participants aged from 35 to 75 with clinical symptoms and radiographic grading (Kellgren-Lawrence 2-4) of knee osteoarthritis were included. INTERVENTIONS: In the intervention group, 55 participants attended a cognitive-behavioural training programme for pain management with six weekly group sessions supervised by a psychologist and a physiotherapist. Concurrently, they and the 56 participants of the control group continued in ordinary GP care that was not altered by the study. MAIN MEASURES: The primary outcome on three-month and 12-month follow-up was the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis index pain subscale. Secondary outcome measures included self-reports of pain and physical function, health-related quality of life, and a comprehensive set of psychological questionnaires. RESULTS: Mixed model results showed no significant differences between the intervention and control group for any measures of pain or function. A significant difference between the groups was found in the Pain Self-Efficacy Questionnaire (Pr = 0.022) in favour of the control group, and in the RAND-36 emotional well-being subscale in favour of the intervention group (Pr = 0.038). Conventional group comparisons of mean follow-up values showed no significant differences in any of the outcome variables. CONCLUSION: This trial could not confirm the hypothesized advantage of a cognitive-behavioural training programme over ordinary GP care in knee osteoarthritis pain patients. TRIAL REGISTRATION: Current Controlled Trials ISRCTN64794760.