Association among pain, disability, and functional capacity in patients with chronic non-specific low back pain: A cross-sectional study

BACKGROUND: Patients with chronic non-specific low back pain (CNSLBP) have pain, disability, and decreased functional capacity, however, the association is still unknown. OBJECTIVE: This study aimed to examine the association between pain, disability, and functional capacity in patients with CNSLBP. METHODS: Thirty participants with CNSLBP were interviewed for demographic data and assessed for pain intensity by visual analog scale (VAS), disability level by Oswestry Disability Index (ODI), and functional capacity comprising functional reach (FR), five times sit-to-stand (5STS), and two-minute step (2MS). The association and linear regression were analyzed using the Spearman correlation coefficient, point-biserial correlation, and multiple linear regression, respectively. RESULTS: A significant association was found between VAS and ODI, VAS and 5STS, 5STS, and 2MS. For demographic data, some variables were significantly correlated to VAS and functional capacity. VAS was also correlated with sex and age, FR was correlated with height, 5STS was correlated with age, and 2MS was correlated with age, body mass index, and physical activity level. CONCLUSIONS: The association among pain intensity, disability level, functional capacity, and demographic data suggests that apart from pain and disability level, functional capacity is associated with pain, which can be recommended for objective assessment regarding some demographic variables that can contribute to clinical outcome measures.