Background: Low back pain (LBP) is one of the main causes of disability in adults. Approximately 80% of LBPs lead to chronic nonspecific low back pain (CNSLBP). Damages to back region may be due to weak musculoskeletal structure, impaired muscle or joint flexibility, changes in muscle tone, and reduced strength and endurance. A set of exercises by small ball was designed by the corresponding and first authors to improve the balance of muscular activity.

Objective: The current study aimed at evaluating the efficacy of small ball exercise program compared to that of Williams flexion exercises, in patients with CNSLBP.

Methods: Among the patients referred to the physical therapy clinics in Tehran, Iran, 30 subjects (16 males and 14 females) were selected through convenience sampling method, considering the inclusion and exclusion criteria, in 2014-2015. Demographic information was recorded. The patients were randomly allocated into one of the intervention groups. For both intervention groups, a 10-session routine electrotherapy was applied (TENS, Hot pack, and ultrasound). Additionally, patients in the intervention group 1 received small ball exercises, but the intervention group 2, they received Williams exercises (as the control). Treatment was conducted by a physiotherapist and a research fellow assessed pain intensity based on visual analogue scale [P1] (VAS) and disability index (Oswestry). Assessments were performed before starting the intervention, after treatment, and then 2 weeks later. Paired and independent samples t tests were employed to conduct the statistical analysis by SPSS version18.

Results: There was no significant difference between the groups based on the baseline characteristics. In both groups, pain and disability showed significant improvement (P <0.05). But in small ball exercise group, reduction in pain (P=0.004) and disability (P=0.03) were more noticeable even after 2 weeks follow-up. The applied treatment program was reported more acceptable and effective by patients.

Conclusion: The current study, while proving beneficial effects of Williams exercise with routine physiotherapy in patients with CNSLBP, showed that substitution of these exercises by small balls exercises could enhance the effect of treatment on pain and disability. Small ball exercise program also showed better outcome in the follow-up, and was ranked higher regarding its impact, ease of implementation, and desirability by the patients.