What is the biggest risk of breast implant surgery The most common complication of breast implant surgery is periosteal contracture, which is manifested by a hard feel of the breast and in severe cases leads to breast deformation and even pain. The envelope is a membrane tissue that forms around the implant after it is implanted in the human body, which appears as a natural response to the foreign body and plays an important role in limiting the displacement of the implant and isolating the implant from the surrounding tissue. The thickness and elasticity of the envelope is crucial to the feel of breast augmentation surgery. In most people, the envelope itself is thin and does not compress the implant significantly, so the breast feels better, but some people overreact to the implant, and the envelope is thicker and shrinks severely, compressing the implant and hardening it to form a contracture of the envelope. Some studies have concluded that personal constitution, foreign body, bleeding, infection, and inadequate peeling cavity are all causative factors of periosteal contracture, but they are not necessarily related. The determining factor for the occurrence of periosteal contracture is still the difference in the body’s reaction to the implant, and the exact cause and mechanism of its occurrence are not yet clear, so it is not yet possible to predict and prevent the occurrence of periosteal contracture, and no surgeon can master and control the appearance of periosteal contracture. Strictly speaking, contracture is not a complication, but a risk that every patient receiving breast implants must face. Fortunately, the incidence of contracture is not high, around 5% according to the literature, and the only potentially effective solution in the event of a momentary contracture is reoperation. However, for some patients, even after eliminating all the causative factors, contracture is still inevitable and the implant must be surgically removed.