Spatial distribution of pain: a descriptive characteristic of chronic pain.

Self-report of spatial distribution of pain has been employed to assess anatomic accuracy of pain description. To date, there is little information on behavioral or psychological characteristics of chronic pain patients as a function of spatial distribution of pain sites. In the present study, 92 patients presenting to a multidisciplinary pain clinic with chronic facial, back, or extremity pain enumerated total sites of pain throughout the body. Responses were categorized into low (1-2), moderate (3-5) and high (6-18) discrete sites of pain. Patients completed self-report scales assessing various activity abilities and health behaviors, a measure of pain description (McGill Pain Language Questionnaire, MPQ), and health related measures of personality (Illness Behavior Questionnaire, IBQ) and cognitive style (Multifactorial Health Locus of Control, MHLC). One-way ANOVAs revealed significant differences as a function of spatial distribution on a number of behavioral (down-time, walking, recreational, vocational and social abilities; total drug use, number of health professionals consulted), pain description (Total Words Chosen-MPQ, Sum of Ranks-MPQ, and Sensory-MPQ) and psychological variables (Disease Conviction-IBQ and Affective Disturbance-IBQ). Results suggest spatial distribution of pain site to be a useful clinical diagnostic indicator of psychological disturbance in chronic pain patients.