A validated, practical classification procedure for many persistent low back pain patients.

We have developed a simple procedure for assigning persistent low back pain patients to one of four mutually exclusive, hierarchically organized classes. The procedure relies on the spatial distribution of a patient's pain and the results of straight leg raise tests to make the assignment. We have applied the procedure to a large group of patients who sought treatment for persistent LBP at several university affiliated tertiary care clinics, and found that the resulting four classes of patients were significantly different from one another in their presentation, and in the way they were evaluated and treated by physicians. We concluded that the procedure may have practical research and clinical applications.