Relationships between muscular impairments, pain, and disability in patients with chronic nonspecific low back pain: a cross sectional study.

To clarify the significance of mechanical impairments, pain, and functional limitations as predictors of chronic low back pain (LBP). Ninety patients with chronic nonspecific low back pain (CNSLBP) were prospectively studied with clinical tests and questionnaires. Changes in muscle extensibility and endurance tests were evaluated and changes assessed in LBP intensity on numeric rating scale 0-10 and severity with Oswestry Disability Index (ODI) 0-100. In the present study we found significant associations between the 4 muscle extensibility and 2 endurance tests and pain at nonspecific patients with chronic LBP (P<0.005). The 2 muscle extensibility and 1 endurance tests were in complete equilibrium with ODI disability and hence showed similar results (P<0.005). The associations between the muscle extensibility and endurance tests and pain were significantly elevated in patients with nonspecific chronic LBP.