The Microvascular Anatomy of Superior and Inferior Gluteal Artery Perforator (SGAP and IGAP) Flaps: A Fresh Cadaveric Study and Clinical Implications

Background Our study aimed to highlight anatomical similarities, differences, and variations in the microvascular anatomy between superior and inferior gluteal artery perforator (SGAP and IGAP) flaps. Method Thirty gluteal flaps (15 SGAP and 15 IGAP) were studied on 22 adult fresh cadavers. We recorded the number and location of perforators, the characteristics of the main perforator (course, length, and diameter at the level of division at the greater sciatic foramen), and the anatomical variations of the submuscular venous plexus. Results The mean number of perforators was similar in both flaps (n = 7). We found a statistically significant difference in the total length of the vascular pedicle between SGAP (mean = 9.80 cm) and IGAP (mean = 13.36 cm) flaps, which correlated strongly with the difference in the intramuscular length (mean difference = 3.40 cm) of the perforator. There was no statistically significant difference in the diameter of the superior and inferior gluteal vessels at the point of pedicle division. The complex submuscular venous plexus, which is typically found on SGAP flaps deep to the sacral fascia, was never encountered on IGAP flaps. Perforators originating from the inferior gluteal artery were found on the lower half of five superior gluteal flaps. These were dominant perforators in two cases. We also report a rare anatomical communication between superior and inferior gluteal vessels deep to the piriformis muscle and a case of atheromatous disease of the inferior gluteal artery. Conclusion Our findings are highly relevant to clinical practice and contribute to the understanding of the vascular anatomy of SGAP and IGAP flaps and the successful use of these challenging flaps.