Neurovascular Mapping of the Labial Fat Pad: Implications for Optimal Martius Flap Harvest

The Martius flap technique includes the cultivation of a well-vascularized labial fat pad from the labium majus for the interposition between a surgical site and the vaginal wall. Our objective was to determine the optimal location for incision and dissection of a Martius flap based on nerve and vascular density in cadaveric dissections.

The labium majus from ten lightly embalmed or fresh frozen cadavers were excised in their entirety. Each specimen was divided into a total of 18 sections per specimen, with nerve and vascular densities subsequently assessed.

The highest nerve density was found within the anterior aspects of the right and left labia. An increased nerve density was observed in the right labium (9% increase vs left, 95% CI 5-12%, p < 0.001) and the medial column (5% increase vs lateral, 95% CI 1-10%, p = 0.019), but no difference was observed in the anterior versus the posterior position (p = 0.88). The highest vascular density was seen in the right lateral labium. There was significantly greater vascular density on the right vs left labium (8% increase, 95% CI 5-12%, p < 0.001), but no significant difference in medial vs lateral (p = 0.55) or in anterior versus posterior (p = 0.86).

These data may provide evidence that utilizing the right labia majus may yield a safer Martius flap. The highest vascularity was in the lateral aspects of the right labial fat pad, and the highest nerve density was in the anterior and medial aspects of the fat pad bilaterally.