Extracorporeal Shock Wave Therapy is effective in the treatment of bone marrow edema of the medial compartment of the knee: a comparative study

Objective: To test the hypothesis that shock wave therapy can produce a statistically significant improvement in symp- toms and imaging features of the knee bone marrow edema syndrome (BMES) within 6 months of treatment. Subjects and Methods: Eighty-six consecutive patients suffering from BMES of the medial compartment of the knee were pre- scribed a course of high-energy extracorporeal shock wave therapy (ESWT) and clinically followed up at 3 and 6 months and finally from 14 to approximately 18 months after treat- ment. Thirty-one patients were unable to undergo ESWT but returned for the 6-month and final follow-up; these were re- ferred to as the conservative (control) group, while the other 55 patients constituted the ESWT group. The Western On- tario and McMaster Universities Arthritis Index (WOMAC) and Visual Analog Scale (VAS) score of each patient were cal- culated at every follow-up. The BME area was assessed using magnetic resonance imaging before treatment and at the 6-month follow-up. Results: Statistically significant improve- ments were observed in clinical scores and in the BME area for both the ESWT and the control group (p < 0.05). The im- provements in the ESWT group were statistically better in all parameters compared with the control group: the ESWT group had a reduction in the BME area of 86% versus 41% in the control group, the VAS pain score improved by 88% in the ESWT group versus 42% in the control group, and the WOMAC score improved by 65% in the ESWT group versus 22% in the control group. Clinical scores were significantly better for patients with medial tibial lesions in the ESWT group. Conclusion: In this study, ESWT reduced pain and the BME area in the knee, with significant clinical improvement noticed 3 months after treatment.