Centralization phenomenon. Its usefulness in evaluating and treating referred pain.

In patients with low-back and radiating leg pain, a clinical phenomenon has been described known as "centralization," which occurs during a mechanical evaluation protocol described by McKenzie. Relocation of the most distal pain in a proximal or central direction characterizes the pain behavior when patients are assessed in this fashion. Centralization typically occurs rapidly and can be maintained. In a review of 87 such patients, centralization occurred in 76 (87%). Its occurrence during initial mechanical evaluation is a very accurate predictor of successful treatment outcome and reliably determines the appropriate direction of treatment exercise. Nonoccurrence of centralization accurately predicts poor treatment outcome and was a helpful early predictor of the need for surgical treatment.