Abstract The authors present a 45-year-old man with bone marrow edema syndrome (BMES) of the medial condyle of the knee. Early diagnosis of BMES was based upon clinical, bone scintigraphy and magnetic resonance (MRI) findings. After failure of the conservative treatment, core decompression was performed. Histological examination showed no evidence of osteoporosis or osteonecrosis. Within 2 months after the operation, the patient was pain-free and he resumed his previous activities. At 1-year follow-up examination, MRI showed complete resolution of all signal abnormalities; at 3-year follow-up the patient remained symptom-free and with no functional limitations.