The study evaluated the manual treatment of dysfunction of the pelvic joints. This is one of many condition causing low back pain. In 1987-1988 a general practitioner with special knowledge of physical examination and manual treatment of lumbar and pelvic dysfunctions made a survey of patients with acute or subacute low back pain as the main cause of the patient-to-doctor contact. Patients with defined criteria of pelvic joint dysfunction (n = 46) were randomized. After dropouts and exclusions, 18 patients with defined criteria of pelvic joint dysfunction received manual treatment, while 21 patients with similar dysfunction served as controls and received placebo treatment in a form of massage. Both groups were seen only once to evaluate whether a single treatment might be sufficient. After a period of three weeks, evaluation was made by an independent observer. Subjective pain measurement and a mobility test showed no significant difference. Sick-leave and consumption of analgesics (both decided by patient) were significantly less in the treatment group.