Non-embolic complications of gluteal fat transfer: A systematic review of the literature.

BACKGROUND: Gluteal fat grafting is a key component of aesthetic body contour surgery and ranks among the most frequently performed cosmetic procedures worldwide. While thromboembolic complications, such as fat embolism, dominate the literature due to their severe and often fatal outcomes, non-embolic complications have received less attention and standardization. These include infections, fat cysts, sciatic nerve injuries, and fat necrosis, which, despite being less severe, can significantly impact patient outcomes. OBJECTIVES: To determine the prevalence of non-embolic complications in gluteal fat transfer and explore strategies for diagnosis, treatment, and prevention. This systematic review aim to fill the knowledge gap in this domain. METHODS: This study adheres to PRISMA guidelines and registered in PROSPERO (CRD420250641715), utilizing databases such as PubMed, Scopus, Scielo, Google Scholar, the Ibero Latin-American Journal of Plastic Surgery and the Mexican Journal of Plastic Surgery. Keywords included "lipoinjection", "fat graft", "fat transfer", "Brazilian butt lift", "buttock", "gluteal augmentation", "complications", "infection", "sciatic nerve injury", "fat necrosis", "gluteal region". RESULTS: A total of 18 studies involving 12,032 patients were analyzed. The mean patient age was 34 years, and the majority were women (97.83%). The overall non-embolic complication rate was 2.67%, with the most common complications being irregularities (32.40%), asymmetries (25.55%), fat necrosis (14.33%), infection (13.08%), cyst formation (10.59%), and abscesses (2.18%). Factors such as the injection plane, methods of fat preparation, and postoperative care were critically assessed. Additionally, a systematic review of the literature regarding mycobacterial infections and sciatic nerve injury was done. CONCLUSIONS: Non-embolic complications in gluteal fat grafting are underreported and require a better understanding to improve patient outcomes and develop effective prevention protocols.