A short large-calibre intrapelvic arterial bridge between the superior and inferior gluteal arteries: an in vivo CT angiographic observation.

PURPOSE: To describe a short, large-calibre intrapelvic arterial bridge between independently established superior and inferior gluteal arteries (SGA and IGA) and to distinguish it from a common gluteal trunk.

METHODS

A pelvic computed tomography angiography (CTA) examination from a 40-year-old man was retrospectively analysed from an anonymised archive using multiplanar reformations, maximum-intensity projections, and three-dimensional vascular reconstructions. Linear and calibre measurements were obtained with workstation callipers and verified by independent review.

RESULTS

On the right, the internal iliac artery divided after 34 mm into anterior and posterior trunks. The anterior trunk gave the obturator and internal pudendal arteries and continued as the IGA (2.6 mm); the posterior trunk gave sacral arteries and continued as the SGA (4.0 mm). The SGA and IGA were connected 44.2 mm distal to the internal iliac bifurcation by a 1.8-mm-long, 3.5-mm-calibre intrapelvic bridge. The SGA exited suprapiriformly and the IGA infrapiriformly. No corresponding bridge was present on the left.

CONCLUSION

The configuration differs from an Adachi Type II common SGA-IGA trunk because the two gluteal arteries are already anatomically separate before the communicating segment. Strict assignment to an Adachi type is not possible from this CTA alone because the umbilical continuation of the hypogastric axis is not demonstrated. Previous cadaveric studies documented SGA-IGA communications, whereas the present observation provides individual in vivo CTA topography and morphometry of a very short, large-calibre bridge.