Differential diagnosis of low-back pain patients: A simple quantification of the pain drawing

Abstract

This study presents and evaluates a simple quantification method for the Patient Pain Drawing (PPD). It is hypothesized that the resulting score can serve as an estimation of psychologic vulnerability and somatization proneness among patients with back pain. The subject sample consisted of 146 consecutive back-pain patients who had been referred to an outpatient physiotherapeutic rehabilitation clinic by general practitioners. They were tested once on three variables from the MMPI (Minnesota Multiphasic Personality Inventory): hypochondriasis (Hs), depression (D), and hysteria (Hy), and four times by means of a test battery including a pain questionnaire, the PPD, and a visual analog scale (VAS). Between the first and second test occasions the patients participated in a physiotherapeutic treatment program. Two follow-up testing sessions were conducted 6 and 18 months after the treatment. Positive relationships were found between Hs, D, Hy and four PPD scores, with the highest correlation coefficients (rho=0.64-0.79, Spearman rank correlation) for Hs and the four different testings with PPD. Forty-eight per cent of the patients with very low PPD scores were without pain after 18 months, compared with only 2% of the patients with high PPD scores. The PPD appears to be a good test for early screening of psychologic vulnerability in back pain patients. The test could easily be used in different primary health care settings and serve as a help in referring patients to more extensive psychologic investigation and adequate treatment.

Key Words:

• Back pain
• MMPI
• Patient Pain Drawing
• Psychologic vulnerability
• Screening