Risk stratification in subpectoral to prepectoral pocket conversion to reduce post-reconstruction animation deformity

Animation deformity is a morbid complication that impacts women undergoing subpectoral implant-based breast reconstruction. Transferring implants from the subpectoral to prepectoral space, pocket conversion, can be performed to minimize this issue. While prior literature has evaluated outcomes associated with this procedure, we investigated the risk factors most commonly associated with post-conversion complications.

We performed a retrospective cohort investigation of women undergoing prepectoral pocket conversion. Pre-conversion clinical characteristics and surgical complications (major and minor) were collected. Predictors for postoperative complications were identified using univariate and multivariate logistic regression models. Odds ratios (OR) and adjusted odds ratios (aOR) are presented with 95% confidence intervals, and p-values were assessed at α = 0.05.

A total of 34 patients (63 breasts) were included. Pocket conversion relieved animation deformity in all breasts. The overall rates of major and minor complications were 14.3% (n = 9/63) and 34.9% (n = 22/63), respectively, by mean follow-up of 11.1 months. After adjusting for confounders, pre-conversion implant rupture (OR= 6.00, CI= 0.99-34.58; aOR= 12.8, CI= 1.15-170.32) and duration of implant placement (OR=1.35, CI= 1.07-1.78; aOR= 1.1, CI= 1.00-1.21) were found to be significant predictors of major postoperative complications.

With a fairly inclusive patient population, this series provides data for improved risk stratification of patients considering conversion to relieve animation deformity. Interestingly, traditional risk factors (namely, body mass index and smoking status) were not significant predictors for postoperative complications, suggesting that conversion may be safe in high-risk patients. Such data support more informed preoperative counseling and wider application of this procedure.