Pilates combined with Cognitive Functional Therapy in women with chronic nonspecific low back pain: A three-arm randomized controlled trial on physical and psychological outcomes

Design Chronic nonspecific low back pain (CNLBP) is a leading cause of functional disability in adults. This randomized controlled trial evaluated the effectiveness of combining Cognitive Functional Therapy (CFT) with Pilates compared to Pilates alone and a control group. The primary outcome was pain intensity. Secondary outcomes included disability, fear of movement, trunk muscle endurance, and postural sway. Setting This single‑blind, three‑arm trial enrolled 120 women aged 20-50 years with mild to moderate CNLBP. Participants were randomly assigned to CFT+Pilates, Pilates, or control groups. Interventions were delivered over 8 weeks. Trained assessors assessed outcomes pre‑ and post‑intervention. Statistical analyses were performed using repeated‑measures ANOVA to examine group × time interactions, followed by Bonferroni post‑hoc tests for pairwise comparisons. Effect sizes were calculated using partial eta‑squared, and clinical relevance was assessed using the MCID. Results Significant group×time interactions were observed for pain intensity (F = 165.85, p ≤ 0.001), disability (F = 89.04, p ≤ 0.001), kinesiophobia (F = 196.48, p ≤ 0.001), and all trunk endurance and postural sway outcomes (p ≤ 0.001). Both intervention groups improved significantly compared with the control group for pain, disability, kinesiophobia, trunk endurance, and postural sway measures (p ≤ 0.001), except for total movement of the COP in the anterior-posterior direction in the Pilates group (p ≥ 0.05). However, Pilates+CFT did not differ significantly from Pilates alone for pain intensity (p = 0.871), disability (p = 1.000), or postural sway parameters (p ≥ 0.05). Significant between-group differences favoring Pilates+CFT were observed for kinesiophobia (p = 0.001), trunk flexion endurance (p = 0.003), and lateral-flexion endurance (p = 0.001). Conclusion Both Pilates-based interventions improved pain, disability, kinesiophobia, trunk endurance, and postural control compared with the control condition. Adding Cognitive Functional Therapy to Pilates provided additional benefits for kinesiophobia and selected trunk endurance outcomes, but not for pain, disability, or most postural sway measures. These findings should be interpreted cautiously given the mild to moderate baseline symptoms and inclusion of women aged 20-50 years.