Acute bone infections can be distinguished from chronic ones, with different symptoms. 1. Acute bone infections: they are usually characterized by localized symptoms, with a more acute onset, followed by generalized fatigue, generalized aches and pains, lack of appetite, coldness, chills, high fever, vomiting, body temperature up to 39°C or higher, rapid pulse, dry mouth, headache, vomiting and other symptoms of meningeal irritation. The patient is irritable and restless, and in severe cases, coma can occur. Newborns and lactating children are prone to excitement, refusal to drink milk, and crying during diaper changes. Bone infection can be localized with severe pain, throbbing pain, and limited pressure pain in the epiphysis, which are the earliest and most important local manifestations. The whole body fever is more frequent, but bone infection will be characterized by a more pronounced pressure pain at the bone end, proving that the infection originates from bone infection. There can be localized skin redness and warmth, and early swelling is not obvious. If a subperiosteal abscess forms, there will be periosteum on the surface of the bone and an abscess will form between the periosteum and the bone, at which point there will be significant local swelling and pressure pain. When the pus penetrates the periosteum to the surrounding soft tissues, the local fluctuating sensation is palpable, at which time the pain is instead reduced because the pressure in the bone is reduced, but the local redness, heat and pressure pain are more pronounced. 2. Chronic bone infection: local symptoms are more and systemic symptoms are less, local symptoms include thickening and deformation of the affected limb, irregular shape of the bone, thin skin on the surface, dark skin color, with hyperpigmentation, hyperpigmentation means local blackness, multiple scarring, sinus tracts will be formed, and there will be inflammatory granulation tissue around the sinus tracts. The sinus tracts are surrounded by inflammatory granulation tissue, which usually rises above the skin surface. The sinus tracts are often discharged with pus or small pieces of dead bone, after which the sinus tracts can be closed and the inflammation gradually subsides. After a period of time, the resistance decreases and the inflammation will flare up again, sometimes for better and sometimes for worse, repeatedly. However, when the resistance decreases, chronic bone infection can come on acutely, and the symptoms are similar to those of acute bone infection.