The protrusion at the back of the neck is a normal physiological phenomenon, that is, the position of the 7th cervical spinous process and the 1st thoracic spinous process in the lower part of the neck is a bony protrusion, so when you touch it with your hand, you will feel the protrusion at the back of the neck, if there are no symptoms, you do not need to deal with it. 2, because the cervical vertebrae have a reverse arch, for example, in the usual low head ambulation The cervical vertebrae will be in a reverse-arch state after a long period of time due to long working hours, long time spent looking at cell phones and computers, or too high pillows during night sleep, which will lead to a protrusion at the back of the neck. 3, due to the formation of sebaceous cysts in the skin or lipomas in the subcutaneous fat layer. The formation of myofibromas in the surrounding muscle tissue may form a bulge at the back of the neck.