[Lumbar facet joint syndrome. Significance of non-organic signs. A randomized placebo-controlled clinical study].

One hundred and nine patients with chronic (greater than 3 months) unilateral low back pain had less than or equal to 2/5 or greater than or equal to 3/5 inappropriate signs (IAS) in 65 and 44 cases, respectively. The patients were randomized in three therapy groups: cortison and local anaesthetic injected intra-articularly into two facet joints (28 patients), the same mixture injected pericapsularly around two facet joints as well (39 patients) and injection of physiologic sodium hydrochloride intra-articularly into two facet joints (42 patients). The effect of the treatment was evaluated within an hour, two and six weeks after the treatment with work status, pain scale, disability score and movements of the lumbar spine. In addition, the patients returned a questionnaire three months after the treatment. Although similar improvement was observed during the follow-up the pain scales and disability scores were, however, in the beginning and at the end of the study more pathological in the group scoring greater than or equal to 3/5 IAS. It is suggested that persistent high levels of IAS depend more on psychosocial factors than on anatomical disorders and therefore explain why the somatic treatment does not work. Identification of these patients may also prevent the doctor from a burn-out syndrome after many failed treatments. This study also shows that if a biological effect of a treatment is to be studied the patients with multiple IAS should be excluded from the material. There was no difference in the results when either intra-articular or pericapsular cortisone and local anaesthetic or saline intra-articularly was used.(ABSTRACT TRUNCATED AT 250 WORDS)