Functionality and Scar Evaluation of the Donor Site in Extended Radial Forearm Flap Phalloplasty: How Affected Is the Arm in Day-to-Day Life?

Background: The radial forearm flap remains the gold standard in phalloplasty in gender-affirming surgery due to its versatility and functional outcome, but the significant donor site morbidity and its impact on daily functioning and aesthetic perception remains understudied. This study provides valuable insights into the mid-term functional and aesthetic outcomes of the forearm in transgender individuals following radial forearm flap phalloplasty using widespread instruments for assessment scoring systems and for the evaluation of postoperative wound healing of surgical interventions in general. Methods: Between January 2013 and March 2018, a total of 47 patients underwent radial phalloplasty at AGAPLESION Markus Hospital, and 20 consented to participate in this cross-sectional, retrospective study evaluating functional and aesthetic outcomes post-radial forearm flap phalloplasty using standardized questionnaires (DASH, POSAS, and SBSES). A univariate median regression of each score was performed to determine the associations with selected variables, and correlation analyses between scores was performed using a nonparametric Spearman rank correlation. Results: Among the 20 participants, the median Quick DASH, DASH functionality, DASH sport and music, and DASH work scores indicated minimal to no functional impairment. Scar evaluations using the PSAS, OSAS, and SBSES scales showed overall patient satisfaction with minimal concerns regarding pigmentation and scar texture. Notably, an increase of 0.27 cm2 in wound surface area added one point to the DASH sport and music score (p = 0.037). Statistical analysis also demonstrated a significant correlation between functional and aesthetic assessment scores. Conclusions: The radial forearm phalloplasty donor site, evaluated by the PSAS, OSAS, and SBSES scales, leads to minimal or no functional impairment; however, the worsening of the DASH sport and music score with increasing wound surface reflects a direct relation between wound size and functional impairment.