RESULTS OF SACROILIAC JOINT DOUBLE BLOCK AND VALUE OF SACROILIAC PAINPROVOCATION TESTS IN 54 PATIENTS WITH LOW-BACK-PAIN

Study Design. This prospective study consisted of the evaluation of a double sacroiliac block in patients with low back pain. Objectives. To determine the prevalence of sacroiliac pain in a selected population of patients suffering from low back pain, and to assess certain pain p rovocation tests. Summary of Background Data. Previous studies have im plicated the sacroiliac joint as a potential etiology of back and leg pain, but none has tested double anesthetic blocks in a prospective fa shion. Methods. Fifty-four patients with unilateral low back pain, pai n, mapping compatible with a sacroiliac origin, tenderness over the sa croiliac joint, and no obvious source of pain in the lumbar spine were selected for a double anesthetic block. The procedure consisted of a thorough clinical examination with a visual analog scale, testing of s acroiliac pain provocation tests followed by a first screening block w ith a short-acting anesthetic. A second examination consisting of the same tests assessed the efficacy of the first block. If results were p ositive, a confirmatory block was performed. All blocks were performed under fluoroscopic guidance. Results. Nineteen patients had a positiv e response to the first block. Among them, 10 (18.5%) were temporarily relieved by the confirmatory block. No pain provocation test reached statistical significance. Conclusion. The present study suggests the s acroiliac joint is an uncommon but real source of low back pain. The a ccuracy of some of the presumed ''sacroiliac pain provocation tests'' is questioned.