Chronic recurrent multifocal osteomyelitis (CRMO) causes abnormal inflammation to occur in and around the bones. Symptoms usually begin in childhood but can occur at any age. Symptoms may include episodes of pain and joint swelling, skin redness, and sometimes a fever. In some cases, CRMO leads to abnormal bone growth, bone deformity, and fractures. CRMO may occur alone or with other skin or bowel inflammation conditions. In rare cases, CRMO occurs as part of one of these genetic syndromes: Majeed syndrome, DIRA or PAPA syndrome. The cause of CRMO is unknown, but a genetic influence is thought to be involved. Diagnosis of CRMO is based on the symptoms, clinical exam, and imaging studies. Other more common conditions may need to be excluded before a diagnosis of CRMO can be made.