The Sternum-Nipple Distance is Double the Nipple-Inframammary Fold Distance in Macromastia.

[BACKGROUND] Reduction mammaplasty is one of the most commonly performed plastic surgery operations. For a majority of techniques, the most common long-term complication is pseudoptosis. It has previously been proposed that upper breast suspensory ligaments (SL) are weaker than lower breast SL. We tested this hypothesis through anthropometry of the proxies for upper and lower SL strength: the sternal notch-nipple (SN-N) distance and the nipple-inframammary fold (N-IMF) distance, respectively.

[METHODS] An institutional review board-approved retrospective review of patients undergoing reduction mammoplasty in an academic faculty practice between 2008 and 2015 was conducted. Patient demographics included age, race, and body mass index (BMI); patient comorbidities included smoking status, diabetes, and hypertension. Breast anthropometric measurements included SN-N and N-IMF. Sternal notch-nipple was used as the primary metric of the upper SL strength, whereas N-IMF was used as the primary metric of the lower SL strength. Intraoperative details included reduction technique and resection mass. Postoperative complications were recorded, including nipple areola complex necrosis and hematoma. Linear regression analysis was performed with the primary endpoint of the relationship between SN-N and N-IMF distance in macromastia.

[RESULTS] Data from 208 patients, totaling 400 individual breast measurements, were collected. The mean SN-N length was 35.1 cm, mean N-IMF length was 16.0 cm, and mean resection weight was 1094 g. Linear regression found that N-IMF distance could be predicted as 45% of the SN-N distance (N-IMF = 0.454 * SN-N). This was a strong relationship, demonstrated by univariate analysis of SN-N and N-IMF (R, 0.624; P < 0.001). A Wise pattern was used in 89.9% of cases; an inferior pedicle was used in 83.7% of cases. Nipple areola complex necrosis occurred in 15 breasts (3.75%). Sternal notch-nipple (R, 0.127; P = 0.011) and N-IMF (R, 0.119; P = 0.017) were both predictive of nipple areola complex necrosis (Table 4).

[CONCLUSIONS] In our series, the N-IMF distance increased 0.45 cm for every 1 cm increase in the SN-N distance. This relationship strengthens our primary hypothesis that the lower pole ligaments stretch at a significantly slower rate than the upper pole ligaments. Taking this into consideration, we suggest that surgeons seeking to minimize pseudoptosis rates should favor techniques that minimally disrupt the lower SL.