The centralization phenomenon. Its usefulness as a predictor or outcome in conservative treatment of chronic law back pain (a pilot study).

Abstract

Two-hundred-forty-three patients with chronic low back pain were studied in a prospective comparative survey to determine whether the "centralization phenomenon" was associated with outcome after an interdisciplinary work-hardening program. The hypothesis was that patients who demonstrated centralization during initial mechanical assessment would have better outcomes than noncentralizers. Overall, subjects had decreased pain intensity ratings (mean 20%), increased lifting ability (6-8 kg), and a 59.2% return-to-work rate at a mean of 9.7 months follow-up. Patients were classified as either centralizers or noncentralizers, based on results of their initial assessment. Changes in pain ratings, one-time maximal weights lifted, Oswestry scores, and return-to-work status were compared between groups. The centralizers reported significant decreases in their maximum pain ratings (centralizers, 16%; noncentralizers, 6%) and had a higher return-to-work rate (centralizers, 68%; noncentralizers, 52%) than the noncentralizers. Centralization can help identify sub-groups within the population with chronic low back pain and could be a useful goal setting and case management tool in the rehabilitation of low back pain.