The spine, ribs and breast bone are very important and serve as the foundation or 'platform' that the breasts sit on. So if they are curved differently or asymmetric, then the breasts are likely to be pointing in different directions. When a breast implant is put in, the resultant breast mound may be dramatically affected by this 'platform'.

If the spine is curved, then a person's posture may be affected. This is usually noticed because one hip or shoulder will be higher than the other. If a shoulder or collarbone is higher than the other, then the breasts will be at different heights or asymmetric.

The ribs and breast bone (sternum) usually come together to make a barrel that is slightly flat on the front side. Sometimes the ribs form different shapes. One half or side of the ribs may protrude out further than the breast bone or the other side. The breast bone may not be flat but may actually protrude out further than the ribs. The breast bone may also be sunken in, and the ribs protrude further out than normal.

Breasts will usually sit on the ribs next to the breast bone. So if the foundation varies for any of these reasons then the breasts may appear different on the chest. It is very interesting that the great majority of these irregularites or anomalies are mild and have not been noticed by the woman until her breast exam. These anomalies may be magnified after a breast implant is placed, so it is important to realize that they exist before plastic surgery for breast augmentation.