refers to positioning of breast implants under the chest (pectoralis major) muscles. This is not exactly correct because the lower edge of the muscle lies at or above the nipple level. Therefore at most only half of a breast implant can be truly submuscular or under the muscle. The advantages of this placement are less visible rippling or upper implant edge. The disadvantage is the muscle can pull the implant upward or distort the implant when flexed.