Medial deviation of the ureters secondary to psoas muscle hypertrophy.

Bilateral medial deviation of mid and distal portions of the ureters can occur as a normal finding in patients with psoas muscle hypertrophy. Two groups of patients are presented, both composed of young, healthy males. In 13 patients, the distance between the ureters at the narrowest point averaged 3.7 cm. Psoas muscle hypertrophy was evident radiographically and confirmed by ultrasound. In 20 patients with normal psoas muscles, the average minimum distance between the ureters was 7.1 cm. The importance of this observation is to avoid overdiagnosis of retroperitoneal disease in this group of young, muscular men. The differential diagnosis and severe examples of this normal variant are presented.