The pectoralis minor is the smaller chest muscle. It lies beneath the pectoralis major and connects several ribs to a projection of the shoulder blade. Its functions include moving and stabilising the shoulder blade.
When an implant is described as being placed behind the pectoralis major, this does not automatically mean it is also behind the pectoralis minor. The term dual plane does not mean placement beneath both muscles either.
The precise implant position and the tissue layers involved should be clearly described during the consultation and in the operation report. This also helps with interpreting later examinations or planning revisions.