Abstract
Introduction and Objective: Controversy continues to exist about the effect of circumcision on penile sensitivity and sexual satisfaction. This study was designed to evaluate penile sensitivity in both circumcised and uncircumcised males. We evaluated both large and small axon nerve fibers using vibration, pressure, spatial perception, and warm and cold thermal thresholds. Measurements both in functional men and men with erectile dysfunction (ED) were obtained to evaluate for differences in penile sensitivities.
Methods: Seventy-nine patients were evaluated. In the cohort evaluated, 54% (43/79) were uncircumcised, while 46% (36/79) were circumcised. All patients completed the erectile function domain of the International Index of Erectile Function (IIEF) questionnaire. Patients were subsequently tested on the dorsal midline glans of the penis. In uncircumcised males, the foreskin was retracted for testing. Vibration (Biothesiometer), pressure (Semmes-Weinstein monofilaments), spatial perception (Tactile Circumferential Discriminator), and warm and cold thermal thresholds (Physitemp NTE-2) were measured. Bivariate relationships were assessed using chi square, t test, and Pearson correlations. Composite null hypotheses were assessed with mixed models repeated measures analysis of variance allowing us to covary for age, diabetes, and hypertension.
Results: Functional group t test analysis only demonstrated a significant (p= 0.048) difference for warm thermal thresholds with a higher threshold (worse sensation) for uncircumcised men. However, significance was lost when we controlled for age, hypertension, and diabetes. For the dysfunctional groups t-test analysis only demonstrated a significant (p= 0.01) difference for vibration (biothesiometry) with a higher threshold (worse sensation) for uncircumcised men. Again, this also lost significance (p=0.08) when controlling for age, hypertension, and diabetes. We also found that overall race is related to circumcision status with Caucasian men 25 times and African American men 8 times more likely to be circumcised than Hispanics.
Conclusions: We present a comparative analysis between uncircumcised and circumcised men using a battery of quantitative somatosensory tests that evaluate the spectrum of small to large axon nerve fibers. We demonstrated that there are no significant differences in penile sensation between circumcised and uncircumcised men with respect to vibration, spatial perception, pressure, warm and cold thermal thresholds in both patients with and without erectile dysfunction.
Note:
The methodology in this study is flawed and displays a fundamental lack of undestanding of foreskin innervation and function. Blustein
et al. carefully retracted the foreskin for the purposes of this experiment. The contribution of the nerves of the foreskin and the
ridged band to sensitivity, pleasure, and satisfaction, therefore, were excluded from the testing. Moreover, this experiment was carried out under static conditions. The foreskin, however, moves dynamically during coitus through its
gliding action, thereby stimulating the nerve endings in the foreskin and providing pleasure and satisfaction to the individual. The evidence provided by this study, therefore, points to the foreskin, not the glans penis, as the major source of penile sensitivity, pleasure, and satisfaction.
