LAUSR

BACKGROUND The anatomy and formation mechanism of the gluteal fold (GF) remain unclear. Given that understanding the anatomy of the superficial fascial system (SFS) may facilitate the improvement of liposuction techniques, this study aimed to clarify and define the anatomic components of the GF. METHODS A total of 20 fresh female buttocks and thighs were sagittally dissected to observe the changes of the SFS along the GF, and were horizontally dissected to observe the SFS on the upper, middle, and lower levels of the buttock. RESULTS Through these dissections, two patterns of SFS in the GF region were identified: retinaculum cutis (RC)-dominant SFS, named the fascial condensation zone, features extremely dense and tough RC, originating from the bony structures, such as the ischium, and radially anchored by the dermis. The fat-dominant SFS features a classical double-layered SFS structure. The RC-dominant SFS is mainly distributed at the medial GF, thus forming the depressed fold. It gradually disappears along the GF and the SFS becomes fat-dominant, making the fold increasingly less visible. At the lateral buttock, the SFS of the buttock and thigh reach an identical status in terms of morphological features, showing a smooth curve between the buttock and the thigh instead of a fold. Hence, based on these findings, different liposuction methods were formulated to manage GF contouring. CONCLUSIONS The SFS of GF region shows a regional variation pattern. Topographic anatomy of the SFS in the GF region helps us understand GF contour deformities and provide an anatomic basis for surgical correction.