One of the main causes of sinus drainage is simply being alive. Every day the human body produces several liters of sinus fluid and mucus, and all of that natural liquid must go somewhere.
It is a area of tenderness of the scalp in which people also sometimes feel stabbing headaches. Others just feel very sore and tender to the touch. It is felt to be caused by irritation of the connective tissue which attaches the muscles of the scalp to the skull (cranium).
Some of the factors that cause sores on the scalp include: 1  Bacterial infections, which include impetigo. 2  Climatic conditions such as cold weather or dry environments. 3  Contamination of the hair follicle.  Deficiency of certain vitamins and nutrients in the 1  body. Excessive stress.  Fungal infections like 1  ringworm. Head  lice.