Iliac artery aneurysm causing isolated superior gluteal nerve lesion.

Lesions of the superior gluteal nerve (SGN) lead to weakness of hip abduction, manifesting itself as a gait abnormality, with contralateral tilting of the pelvis with each step. Causes are numerous and may occur at different anatomical locations before the nerve enters the suprapiriform foramen, in the foramen itself, or after the nerve has exited the foramen. This case report describes an SGN lesion by a large iliac artery aneurysm in a patient presenting with a gait disorder.