Copyright 983 by The Journal of Bone and Joint Surgery. Iniorporateil 560 THE JOURNAL OF BONE AND JOINT SURGERY Current Concepts Review The Use of Psychological Tests in the Evaluation of Low-Back Pain*

Low-back pain is an enormous medical problem, as two of every three people will suffer from back pain at some point in their lives 10.13,14,24 It has been reported that on any given day, more than seven million Americans re-ceive some kind of treatment for their back problems. Unfortunately, this treatment is often unsuccessful. Of the 1.25 million Americans who injure their backs annually, more than 65,000 are so resistent to treatment that they qualify for permanent disability ’. Even surgery provides no guarantee of pain relief. In fact, the number of back pa-tients who are helped by surgery may be as low as 10 per cent at the end of five years2’9. One reason for the low success rate is the failure of clinicians to understand the complexities of pain. Pain is more than just a physiological phenomenon. It is also