MRI-controlled analysis of 104 patients with painful bone marrow edema in different joint localizations treated with the prostacyclin analogue iloprost

Background: Bone marrow edema (BME) is a common cause of pain of the musculoskeletal system. The aim of the study was to assess the efficacy of iloprost in the treatment of BME of different localizations and etiologies. Patients and methods: We reviewed 104 patients (54 male, 50 female) with BME, Their mean age was 52.8 +/- 14.7 years. BME was located 50 times in the knee, 19 times in the talus, 18 times in the femoral head and 17 times in other bones, Patients were allocated to three distinct etiological groups: 27 cases were estimated to have idiopathic BME, 16 post-traumatic BME and the other 61 BME secondary to activated osteoarthritis or mechanical stress. Therapy consisted of a series of five iloprost infusions with either 20, 25 or 50 mu g of iloprost given over 6 hours on 5 consecutive days each. Results: At the clinical follow-up four months after therapy, the pain level of the 104 patients at rest had diminished by a mean of 73% (p < 0.0001): 64% of patients reported a reduction, 34% no change and 2% an increase in pain at rest. Pain under stress decreased by a mean of 59%, (p < 0.0001): 76% of patients had less pain during activity, 22% no change from baseline and 2% an increased pain level. On MRI, 65% had significant reduction of BME size or complete normalization and 20% showed no change. Worsening of the MRI pattern was found in 2%. 13% were lost to MRI follow-up. Side effects were significantly reduced by lowering the daily dose from 50 to 20 mu g, without impairment of therapeutic effect. Conclusion: The authors conclude that the use of parenteral iloprost might be a viable method in the treatment of BME of different etiologies.