The side of the breast matters
The lateral chest wall is the area beside the breast, under the arm and along the side of the ribs. Fullness here, often called side boob or a bra roll, makes the breast look wider and can hide the shape you have worked to create. Surgery that ignores it can leave the silhouette looking unfinished.
The lateral border of the breast also defines where the breast ends and the body begins. A clean line helps the result look natural.
A note about the term thoracoplasty
In general surgery, thoracoplasty refers to a different operation involving the ribs. In aesthetic practice, patients sometimes use the word for contouring the chest wall. Here we mean liposuction and soft-tissue contouring of the lateral chest, not rib surgery.
How it is added
Liposuction removes excess fat from the sides of the chest and the bra roll through tiny incisions, usually in the same operation as the breast procedure. In some people with extra skin, excision is needed in addition.
Fat that is removed can sometimes be processed and used for fat grafting to the breasts, which turns an area of excess into a source of volume.
Why plan it together
Planning the breast and the lateral wall together lets the surgeon balance them. Breast size, base width and lateral fullness all affect each other. A lift or a reduction often looks better with the side contoured, and bras fit better.
Limits and risks
Liposuction does not treat loose skin and is not weight loss. Risks include contour irregularity, asymmetry, numbness, fluid collection and the need for more surgery. Total operating time is limited for safety, so combined plans are sized to suit you.