In general, the normal pinching of the chest will not feel pain, but if the pinching force is relatively large, more than the body’s pain threshold will feel pain. Therefore, if the slightest pinch will also feel pain, mainly in the following cases: first, the local tissue of the chest due to external forces damaged tissue congestion, edema, acute inflammatory changes, at this time, the skin tension, sensitivity is reduced, the slightest pinch will also feel pain; second, acute mastitis, common in lactating women, mostly Staphylococcus aureus through the cracked nipple infection of the breast tissue, causing acute mammary gland The pain may not be intense with light touch at the beginning of the infection, but after the formation of a breast abscess at the end of the infection, even with light touch, the pain can be intense; third, cystic hyperplasia of the breast, due to an imbalance in the ratio of estrogen and progesterone, resulting in breast hyperplasia and incomplete replenishment, the interstitial tissue of the breast is congested and edematous, which can be painful with light touch.