Clinical and psychological classification of non-specific low-back pain. A new study in primary care practice

This study aimed to explore the clinical and psychological features of non-specific low-back pain (LBP), and to evaluate a classification of patients based on the relationship between psychological disturbances and LBP clinical presentation. An unselected population of consecutive patients (n = 262) complaining of low-back pain to primary care physicians of the Epidemiology Team of the French Rheumatology Society, in October and November 1991, was studied. Measures included a standardized clinical evaluation of the back and a psychological assessment using the General Health Questionnaire. Ninety nine patients (38%) were classified as having a psychological disorder. The following symptoms: psychological precipitating event, permanent pain at night, diffuse spinal pain, pain increased by changing climate, pain increased by psychological factors, dysesthesias in the back, non-anatomical tenderness, were found to be closely associated with the existence of psychological disorder. Correspondence and cluster analyses provided support for the four-group classification of low-back pain previously devised. This classification may be interpreted through the relationships between psychological disturbances and the back clinical features. Although the study was mainly descriptive and used a cross sectional design, its results underline the importance of psychological influence on low-back pain presentation, and suggest the interest of a psychiatric assessment in low-back pain patients. Psychological disorders appear to be frequent in these patients and specific management of these disorders may prove useful.