Understanding dual plane means you have to understand some basic concepts about the muscle anatomy of the chest wall.
The chest wall muscle important in breast augmentation is called the
pectoralis major muscle….otherwise known as the pec muscle. This muscle extends
from the arm bone, called the humerus, near the shoulder, and attaches to the
chest wall near the midline.
How the implant is placed in relation
to this muscle is important in determining the final long term result.
The implant can be placed in front of
However, most surgeons choose to place
the implants under the muscle which is often referred to as a subpectoral
placement or “unders”.
However, an implant placed under the muscle is never completely covered
by muscle, with the lower part of the implant extending below the lower border
of the muscle.
Dual plane refers to implants that are partially covered by muscle and partially
covered by breast tissue. Therefore, effectively ALL under the muscle implants
are "dual plane".
A standard subpectoral implant pocket is often referred to as a dual
plane type 1 placement.
The placement of the implant in a dual plane type 1 follows several steps:
- The lower end of the pec muscle is identified
and then detached from the chest wall at the lower end to make room for the
implant. However, as the muscle remains attached to the overlying breast tissue
it doesn’t retract, or move too far.
- A space, or pocket, is then created under the
pec muscle large enough to accommodate the chosen implant.
- Once the pocket is created, the implant is then
inserted and positioned.
- In this situation the outer/lower aspect of the
implant is not covered by muscle - "dual plane".
as the muscle remains attached to the breast tissue and close to the lower
curve of the breast, then as this muscle contracts it often pulls the skin in
causing a groove along the lower breast curve. This is referred to as a dynamic
double bubble and is quite common.
Another form of under the muscle implant placement is the dual plane
In this situation, many of the
surgical steps are the same as the dual plane type 1.
- The lower end of the pec muscle is identified.
- However, unlike the dual plane type 1, the
breast tissue is detached from the pec muscle approximately up to the level of
- The space under the muscle is then opened and
the lower end of the pec muscle is detached from the chest wall.
- With the muscle now detached from the both chest
wall and the breast tissue, this segment of the pec muscle retracts upwards.
- With the under muscle pocket created, the
implant is inserted and positioned and the wound is closed.
The dual plane type 2 implant placement results in less of the implant
covered by muscle along the lower half of the implant ….and this can have the
benefit of a fuller more curvaceous underboob.
It also significantly reduces the
potential for a dynamic double bubble as this muscle is no longer close to the
skin along the lower curve of the breast.
One of the negative issues of a dual
plane type 2 approach is that the detached segment of pec muscle is no longer
functional…. so you can expect a slight reduction in pec muscle strength.
However for the majority of people this is not noticeable.
Pros and cons exist for each technique so speak to your plastic surgeon to find out what will give you the best outcome.