First of all, you have to find an old Chinese medicine practitioner in the traumatology department to see if there are any important acupoints. If there is, he will use Chinese herbal medicine for external application and oral administration to open acupoints. If it is an ordinary old wound, you need specially brewed medicinal liquor to wipe the wound every day to cooperate with the internal medicine of old Chinese medicine. The position of the old wound will get more and more painful before, because the drug reaction is removing blood stasis. When the medicated wine is rubbed by hand, the wound will not hurt and the congestion will be almost cleared. Congratulations, your old wound will heal.
Anyone who says that quick treatment of old injuries is a lie. No one can't be cured in a month. I have personally experienced many places and it still hurts after a few days, and I was cured by the old folk Chinese medicine.