Expanding the Concept of Hip Expansion By Fat Grafting to Recreate the Female Silhouette in a Series of 2,669 Patients.

Goals/Purpose: Hip expansion through fat grafting is an important method to enhance the female silhouette. Fat transfer is a versatile technique commonly utilized in both aesthetic and reconstructive surgery to improve areas of deficiency and create a more harmonious result. The differences in hip shape and the factors that can influence the results need careful evaluation of the surface anatomy of the hip aesthetic unit. This unit has clear boundaries, contours, and zones that should be managed effectively to achieve a balanced, feminine profile. The hip aesthetic unit, particularly its anterior subunit, has yet to be fully explored. The authors present their experience with hip expansion via fat transfer and its use as an adjunct in various aesthetic procedures, including, but not limited to, abdominoplasty. The concepts of hip expansion by fat grafting and the role of the anterior subunit in improving the anterior female profile and achieving more contoured hips are explained.

Methods/Technique: A retrospective review of 2,669 consecutive cases of hip expansion was conducted between January 2014 and October 2023. Photographic documentation was obtained before the procedure, and during follow-up appointments at one, three, six, and eight months, and, when feasible, after one year. We included patients who underwent hip expansion as an adjunct to abdominoplasty, buttock augmentation with fat, buttock augmentation with implants, or liposuction alone combined with hip expansion. Patient demographics, preoperative planning, operative details, and outcomes were obtained from medical records, CosmetAssure billing claims, and photographic documentation.

Results/Complications: Hip expansion was successfully achieved as a part of 2,669 cases, including abdominoplasty (1,171), buttock augmentation with fat (946), buttock augmentation with implants (335), and liposuction alone combined with hip expansion (217). The fat grafted to the hip ranged from 80 milliliters (mL) to 750 mL on each side, averaging 300 mL. The average extracted fat was 3500 mL, ranging from 2500 to 6000 mL. Complications related to fat grafting of the hips included local surgical site infection requiring oral antibiotics (2, 0.07%) and liquefactive necrosis (2, 0.03%). Fifty (1.9%) patients required a second round of fat transfer due to a desire for wider hips, fat reabsorption, or dissatisfaction. There were 10 (0.3%) cases of asymptomatic fat necrosis with one patient requiring direct excision. No cases of fat embolism occurred.

Conclusion: Hip expansion offers a safe and reliable technique that enhances aesthetic outcomes when used as an adjunct to trunk and torso body contouring procedures. A thoughtful preoperative assessment based on specific zones is necessary to achieve satisfactory outcomes. For better results, particularly in the anterior view, the anterior subunit needs to be enhanced as far as the anterior inferior iliac spine is concerned. For a more balanced female silhouette, the hip aesthetic unit should be an integral part of the body contouring procedure, particularly for patients seeking an improved waist-to-hip ratio.