Pain and swelling that occurs under the local skin. There are always different opinions about the explanation of gangrene. In Neijing, carbuncle is the general name of all sores. Surgeons of past dynasties named many diseases with different properties and different treatment methods according to their own experiences. For example, "fierce gangrene" in Neijing refers to carbuncle of larynx (chin cellulitis). "Poultry gangrene" mentioned in Medical Zong Jin Jian refers to erysipelas on the back.
The "gangrene adjustment", "gangrene stagnation" and "carbuncle" mentioned in "Surgical Masterpiece" refer to the furuncle of the hand. Another example is axillary gangrene (axillary lymph node tuberculosis), femoral gangrene (inguinal lymph node tuberculosis) and rib gangrene (chest wall tuberculosis, rib tuberculosis), which are now classified as scrofula and phlegm respectively according to their nature.
Lymphadenitis is a chronic infectious disease, which mainly occurs in the neck. Tuberculosis is like a bead, which is characterized by slow onset. At first, tuberculosis was like beans, with the same skin color and no pain. Later, it gradually increased its growth and turned dark red when it became pus. After the pus is broken, it is thin and flocculent, which is equivalent to lymph node tuberculosis in western medicine. Phlegm flow is a disease that occurs in bones and joints. It is characterized by slow onset, late suppuration, and pus as thin as phlegm after festering, which is equivalent to bone and joint tuberculosis in western medicine.