Chronic non-bacterial osteomyelitis is a multifocal inflammatory bone disorder. The pathogenesis is unknown. The disease is mainly diagnosed in childhood. There is a strong association with inflammatory disorders of the skin, mainly psoriasis. The disease is characterized by recurrent episodes of pain and disability. It is unclear if SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, osteitis) might be the adult version of chronic non-bacterial osteomyelitis. The disease can persist in adulthood and course chronic bone deformations.