Cross-sectional differences of physical and psychosocial measures in low back pain according to pain chronification risk groups.

Objective: To investigate whether low-back-pain patients classified based on the risk of pain chronification (low, medium, high) differ in psychosocial and physical function measures, and whether these subgroup differences are moderated by age, gender, and body mass index.

Methods: In this cross-sectional study, 595 Austrian patients with chronic low back pain (68% female; mean age: 53 ± 6.7 years) completed the STarT Back screening tool, visual analogue scale, Roland Morris Disability Questionnaire, Pain Disability Index, 5-level European Quality of Life Questionnaire, Hospital Anxiety and Depression Scale, and Avoidance-Endurance fast screen. Physical function tests assessed maximum trunk strength, trunk range of motion, and hand grip strength, while multivariate analyses of variance evaluated differences among the risk groups.

Results: The intensity of physical and psychosocial problems differed significantly among the pain chronification risk groups. Physical function also varied across subgroups, with the high-risk group exhibiting the weakest muscle strength and the greatest stiffness. Gender significantly moderated the association between pain risk group and trunk strength.

Conclusion: In people of working age with chronic low back pain, the STarT risk of pain chronification was correlated with physical and psychosocial variables. Moreover, this screening tool can be used irrespective of personal factors such as age, gender, and BMI.