The main symptom of subcutaneous nodules is the appearance of a round hard lump deep in the skin, which may be accompanied by pain and pressure. Subcutaneous nodule refers to the substantial damage that occurs in the subcutaneous tissue, often caused by metabolite accumulation, inflammatory stimulation or local tissue proliferation, which may cause the patient to have a swelling under the skin, which may be elevated above the plane, or may not be elevated above the surface of the skin, which can only be touched, and which may move. When the subcutaneous nodule increases in size and squeezes the local blood vessels and nerves, it can lead to pain or squeezing pain, and in severe cases, it can damage the normal function of the joints and bones and lead to disability. Most subcutaneous nodules are completely absorbed and disappear, while some may break down and form a scar. When subcutaneous nodules are detected, patients can be treated under the guidance of a doctor to avoid delays.