Ultrasound-Guided Gluteal Fat Grafting: What is the Evidence? A Systematic Review and Meta-Analysis

Buttock augmentation has become one of the most sought-after cosmetic procedures, but concerns over fat embolism-related fatalities have raised significant safety issues. Guidelines emphasize that fat grafting should remain in the subcutaneous layer, avoiding intramuscular injection. This systematic review and meta-analysis assess the efficacy and safety of ultrasound-guided gluteal fat grafting. A systematic search of PubMed, Cochrane Central Register of Controlled Trials, and Embase was conducted until July 2024, analyzing patient satisfaction, complication rates, mortality, fat embolism, fat necrosis, infection, and seroma. Statistical analyses, including the Freeman-Tukey Double Arcsine Transformation, were performed using R version 4.1.2. Four studies with a total of 6235 female patients (mean age 34 years, BMI 30.1 kg/m2) met the inclusion criteria. The pooled analysis showed no reported mortality (0.00 per 100, 95% CI, 0.00-0.00) or fat embolism (0.00 per 100, 95% CI, 0.00-0.00). Minor complications occurred at a rate of 6.32 per 100 (95% CI, 3.23-10.27), with seroma at 2.94 per 100 (95% CI, 0.97-5.75), infection at 0.23 per 100 (95% CI, 0.00-0.96), and fat necrosis at 0.09 per 100 (95% CI, 0.01-0.23; I2 = 0). The findings indicate that ultrasound-guided gluteal fat grafting is associated with low complication rates and no reported serious adverse events, such as death or fat embolism, reinforcing its role as a safer technique for buttock augmentation. Level of Evidence: 3 (Therapeutic).