A large and painful sack on the back is considered to be the result of local soft tissue infection or an infection secondary to a sebaceous cyst, and the patient may also have significant fever, local redness, congestion, tenderness, and even skin edema. The patient should promptly choose surgery for incision and drainage, and should be carefully separated and segregated during the operation to avoid the residual pus cavity and the recurrence after the surgery, and after the operation, attention should be paid to regular drug changes and anti-infection treatment. In addition, it is best not to drink alcohol during the treatment period to avoid stimulating scar tissue proliferation and affecting wound healing, while soft tissue infection is mainly related to poor local hygiene. Soft tissue infections are mainly related to poor local hygiene and are caused by sebaceous gland obstruction and secondary infection, and in severe cases, abscesses may form with significant fever and chills.