Synovitis-acne-pustulosis-hyperostosis-osteomyelitis syndrome, also known as SAPHO syndrome, is an abbreviation of the following five English words: synovitis, acne, pustulosis, hyperostosis, and osteomyelitis. SAPHO syndrome is a chronic disease that mainly affects the skin, bones, and joints. The disease mainly includes bone lesions and palmoplantar pustulosis. Sasaki first described a case of aseptic hypertrophic osteitis of the clavicle with palmoplantar pustulosis in 1967, and more than 250 cases have been reported since then. In 1987, Charnot et al. summarized the symptoms and took the first letter of each lesion to propose the name of SAPHO syndrome. They divided the bone and joint lesions of this syndrome into four groups: rheumatic manifestations associated with acne (masses, eruptions, hidradenitis, suppuration), palmoplantar pustulosis, sterno-clavicular hypertrophy, and chronic recurrent osteomyelitis. All patients had sterno-clavicular joint involvement and caused aseptic hypertrophic osteitis. In 1987, French physician Charmot et al. proposed that palmoplantar pustulosis, suppurative hidradenitis or severe acne accompanied by sterno-costoclavicular hypertrophy, chronic recurrent multifocal arthritis, sacroiliitis and other lesions be collectively referred to as SAPHO syndrome. The common feature is that skin lesions have aseptic pustules at a certain period, and bone lesions include aseptic osteitis, aseptic osteomyelitis and arthritis. Kawdi et al. noticed that there were similar inflammatory cell infiltrations in the skin, bone and synovial tissues, and believed that these three lesions had a common cause. Although there have been more and more clinical reports in the past decade, there are almost no reports on the etiology and pathogenesis of the disease. Currently, there are less than 300 cases reported worldwide, more than 80% of which are concentrated in Europe, and the rest are in North America, Japan, Australia and other countries and regions. There are no official reports in my country.