Redefining the Genital Abnormality in the Robinow Syndrome

Abstract

Purpose We defined the anatomical structure of the male genital abnormality in the Robinow syndrome. Features of this syndrome include mesomelic brachymelia of the arms, bifid terminal phalanges of the hands and feet, characteristic facies, skeletal anomalies and hypoplastic external genitalia. Materials and Methods Penile anatomy of 3 patients with the Robinow syndrome was assessed using computerized tomography and magnetic resonance imaging. Results were compared to those of 4 controls who underwent imaging for pelvic malignancies. Results Cross-sectional imaging showed that normal penile crura were inserted onto the anteromedial aspect of the pubic bone. In contrast, in the Robinow syndrome they were inserted inferiorly and posteriorly onto the medial aspect of the ischial tuberosity. In addition, the crura in the Robinow syndrome extended posterior to a line intersecting both femoral shafts. Compared to controls, there was a significant gap between the symphysis pubis and dorsal aspect of the penis. Conclusions The penile anomaly in the Robinow syndrome is due to abnormal insertion of the penile crura, resulting in a penis that appears shorter and more inferiorly placed between the legs.