Placing breast implants under the chest muscle, a procedure called post-pectoralis or sub-muscular placement, has been the standard approach to implant breast reconstruction for decades. But now some surgeons are placing the implants on top of the muscle, in an effort to reduce complications like pain, weakness and breast deformities that can occur with sub-muscular implants when the chest muscles are flexed.

The alternative approach is made possible in large part by the use of biological mesh products — called acellular dermal matrices — that can substitute for muscle to cover, protect and support breast implants.