An Anatomic Appraisal of Biplanar Muscle-Splitting Breast Augmentation

Biplanar muscle-splitting (BMS) breast augmentation is a relatively new technique for which the safe regions of dissection have not been delineated.

The authors performed cadaver dissections to elucidate the surgical anatomy of the BMS pocket and to infer the safety of this method.

The breasts and chest regions of 5 female cadavers were dissected to identify anatomic landmarks and to ascertain the optimal split site in the pectoralis major. CS was defined as the lateral junction of the middle and caudal one-third of the sternum, and the sternal index was defined as the ratio of the length of the sternum to the distance from CS to the most medial major nerve branch.

Initiating the muscle split at CS is likely to avoid nerve injury. The mean distance from CS to the most medial nerve branch was 15.36 cm. The sternal index is a reproducible marker of the extension of the nerve branches in relation to chest size. The sternal length and the cranio-caudal length of the pectoralis major were similar, enabling reliable planning of the muscle split site.

If dissection is limited to the safe regions delineated herein, BMS breast augmentation is likely to be a safe procedure for most patients. By maintaining the connections between the pectoralis major and its origins, a breast deformity associated with muscle contraction may be avoidable.