Bone Marrow Edema Syndrome of the Foot Treated with Extracorporeal Shock Wave Therapy: A Retrospective Case Series.

To determine the validity and safety of extracorporeal shock wave therapy (ESWT) in the treatment of bone marrow edema syndrome (BMES) of the foot. Twenty patients diagnosed as foot BMES in our Center were followed and treated by ESWT for 1 to 2 courses. The target of the ESWT treatment was the most obvious foot tenderness, or the most obvious part of bone edema on magnetic resonance imaging (MRI). One course of ESWT was 1 time/week, 5 times in total, with the shock wave energy flow density 0.18 mJ/mm. The visual analog scale (VAS) and the American Orthopedic Foot and Ankle Society (AOFAS) scores of the foot were recorded before treatment, at 3 months after treatment and the last follow-up; the areas of BME before treatment and at the last follow-up were measured by the fat suppression MRI. Complications during treatment were also recorded. Twenty follow-up patients were obtained. Compared with the pretreatment, the patients had significant improvement in various indicators at 3 months after treatment (p < 0.01). The sagittal MRI at the last follow-up showed that the BME area decreased significantly (p < 0.01). Two patients developed transient erythema on their skin after treatment and alleviated after 2 days of rest. No serious complications were found during treatment. Our findings show that for patients with foot BMES, the use of ESWT treatment can effectively relieve local pain, improve the motor function of the foot and ankle. Two courses of treatment may be required for some patients.