Centralization of symptoms and lumbar range of motion in patients with low back pain

This quasi-experimental repeated measures study examined the relationship between centralization of symptoms and lumbar flexion and extension range of motion (ROM) in patients with low back pain. Rapid and lasting changes in lumbar ROM have been noted with centralization of symptoms. However, no study has objectively measured the changes in lumbar ROM occurring with centralization. Forty-two adult subjects (mean age, 45.68 years; SD=15.76 years) with low back pain and associated lower extremity symptoms were followed by McKenzie trained physical therapists. Subjects' lumbar ROM was measured at the beginning and end of each patient visit by using double inclinometers, and pain location was documented. Subjects were grouped as 1) centralized, 2) centralizing, or 3) noncentralized for comparisons of symptom and ROM changes. Data were analyzed by using multivariate analysis of variance and one-way analysis of variance. Significance was set at 0.05. A significant difference was found between initial and final mean extension ROM in the centralized and centralizing groups (p=0.003). No significant difference was found in the noncentralized group (p<0.05). Subjects (n=23) who demonstrated a change in pain location during the initial visit also showed a significant (p<0.001) change in extension ROM, whereas patients with no change in pain location (n=19) did not (p=0.848). Lumbar extension ROM increased as centralization occurred.