The diagnostic criteria for osteomyelitis are based on clinical manifestations, auxiliary examinations. Chronic osteomyelitis combines clinical manifestations, auxiliary examination and biopsy. 1. Acute osteomyelitis: manifested as localized pain without obvious cause in the limb, localized redness, swelling, heat and pain, which cannot be relieved by general pain-relieving drugs. Body temperature mostly shows high fever, body temperature is above 39 degrees and continuously elevated. Auxiliary examination laboratory tests of white blood cells, blood sedimentation and c-reactive protein are obviously elevated. Blood culture can clarify the pathogenic bacteria. there is no obvious change in the radiographs taken within 2 weeks. 2. Chronic osteomyelitis: local symptoms, repeated ulceration and pus flow, accompanied by fatigue, radiography can be early detection of bone sclerosis with the prolongation of time there will be bone localized resorption area or cavity, bone destruction, dead bone formation or disappearance of bone marrow cavity. Localized pathology and bacterial culture can be used to make a definitive diagnosis. Osteomyelitis patients need to go to the hospital, early treatment, standardized treatment.