The Alcock syndrome: temporary penile insensitivity due to compression of the pudendal nerve within the Alcock canal.

Penile insensitivity is a symptom commonly observed after traumatic or iatrogenic nerve lesions, or in association with neurological or vascular diseases. In contrast, we report 2 cases of intermittent genital hypesthesia that occurred in cyclists after long-term bicycle riding. Anatomical studies show that this condition was probably caused by an irritation of the pudendal nerve during its course through the Alcock canal as reported in the literature. No pathological findings were demonstrated on extensive physical examinations, medical history and all medical imagings (sonography of abdomen, prostate and testes, and magnetic resonance imaging of the pelvis and lumbar spine) as well as radiodiagnostics and Doppler sonography, nor was there evidence of other neurological disturbances. The symptoms in the 2 patients spontaneously resolved after 4 and 7 weeks, respectively, without specific medical therapy.