Techniques and Applications of Lower Extremity Feminization and Masculinization.

Background: Significant differences exist between feminine and masculine lower extremities, and this region contributes to gender dysphoria in transgender and nonbinary individuals. Methods: A systematic review was conducted for primary literature on lower extremity (LE) gender affirmation techniques as well as anthropometric differences between male and female lower extremities, which could guide surgical planning. Multiple databases were searched for articles before June 2, 2021 using Medical Subject Headings. Data on techniques, outcomes, complications, and anthropometrics were collected. Results: A total of 852 unique articles were identified: 17 met criteria for male and female anthropometrics and 1 met criteria for LE surgical techniques potentially applicable to gender affirmation. None met criteria for LE gender affirmation techniques specifically. Therefore, this review was expanded to discuss surgical techniques for the LE, targeting masculine and feminine anthropometric ideals. LE masculinization can target feminine qualities, such as mid-lateral gluteal fullness and excess subcutaneous fat in the thigh and hips. Feminization can target masculine qualities like a low waist-to-hip ratio, mid-lateral gluteal concavity, calf hypertrophy, and body hair. Cultural differences and patient body habitus, which influence what is considered "ideal" for both sexes, should be discussed. Applicable techniques include hormone therapy, lipo-contouring, fat grafting, implant placement, and botulinum toxin injection, among others. Conclusions: Due to lack of existing outcomes-based literature, gender affirmation of the lower extremities will rely on application of an array of existing plastic surgery techniques. However, quality outcomes data for these procedures is required to determine best practices.