Effect of Passive Versus Active Aquatic Therapy Over Conventional Physiotherapy in Patients With Chronic Low Back Pain: A Randomized Crossover Trial — Study Protocol

Abstract

Background Chronic low back pain (CLBP) is a highly prevalent musculoskeletal disorder worldwide, often associated with long-term disability and reduced quality of life. 1,2 Conventional physiotherapy continues to be the cornerstone of management; however, alternative approaches such as aquatic therapy have gained increasing attention in recent years due to their surging therapeutic benefits. 3,4 Within aquatic rehabilitation, various methods including passive aquatic therapy (Watsu) and active aquatic therapy are being implemented. 5,6 Despite their growing use, comparative evidence evaluating the relative effectiveness of these two approaches especially against conventional land-based physiotherapy remains limited. 7,5 Objectives To compare the effectiveness of active aquatic therapy, passive aquatic therapy (Watsu), and conventional physiotherapy in reducing pain, improving lumbar range of motion (ROM), and enhancing functional ability in individuals with CLBP. Methods A single-center, randomized crossover trial will be conducted involving 12 participants diagnosed with CLBP. Each participant will undergo three interventions i.e active aquatic therapy, passive aquatic therapy (Watsu), and conventional physiotherapy in a randomized sequence. Each intervention will be administered for 4 weeks, with a one-week washout between interventions to minimize carryover effects. Clinical outcomes will be collected at baseline and after each intervention phase by a blinded assessor. Statistical analysis Data will be analyzed using repeated-measures ANOVA to compare within-subject differences across the three interventions for pain (VAS), functional disability (ODI), and lumbar ROM. Post-hoc pairwise comparisons with appropriate corrections (Bonferroni) will be performed when significant main effects are observed. A significance level of p < 0.05 will be considered statistically significant. Missing data procedures are pre-specified (see Statistical Methods section). 8 Discussion This randomized crossover trial is to be conducted in a single-center setting with 12 participants. Extending each intervention to 4 weeks allows for meaningful improvements in pain, lumbar ROM, and functional ability, while the crossover design minimizes between-subject variability. It is anticipated that active aquatic therapy will most improve ROM and function, passive aquatic therapy (Watsu) will be most effective for pain relief, and conventional physiotherapy will provide moderate benefits. 7,5 Access to an in-house hydrotherapy pool in Thumbay rehabilitation centre ensures consistent intervention delivery and enhances feasibility. A structured follow up and motivation sessions will be arranged to prevent any retention and facilitate active participation of patient without affecting the compliance.