UROGENITAL TRAUMA

Erectile dysfunction after a long-distance cycling event: associations with bicycle characteristics
Dettori JR, Koepsell TD, Cummings P, Corman JM
Department of Epidemiology, School of Public Health and Community Medicine, University of Washington and Department of Urology, Virginia Mason Medical Center, Seattle, USA
J Urol. 2004; 172: 637-41

• Purpose: We conducted a prospective cohort study to examine the relationship between bicycle characteristics and the occurrence of erectile dysfunction.
• Materials and Methods: Subjects consisted of 463 cyclists completing a cycling event of at least 320 km who were free of erectile dysfunction before their event.
• Results: The cumulative incidence of erectile dysfunction after the ride was 4.2% (95% confidence interval [CI] 2.4%-6.8%) and 1.8% (95% CI 0.7%-3.8%) 1 week and 1 month after the event, respectively. Bicycle characteristics associated with an increased risk of erectile dysfunction included a mountain bicycle compared with a road bicycle (risk ratio [RR] 4.1, 95% CI 1.6-12.5), and the relative height of the handlebars parallel with or higher than the saddle compared with the relative handlebar height lower than the saddle (RR 3.0, 95% CI 1.1-9.3). Perineal numbness during the ride was experienced by 31% of the cyclists and was associated with erectile dysfunction (RR 4.4, 95% CI 1.6-12.7). Saddle cutouts were associated with an increased risk of erectile dysfunction among those who experienced numbness (RR 6.0, 95% CI 1.3-27.1), but the association was reversed among those who did not report numbness (RR 0.3, 95% CI 0.0-2.5).
• Conclusions: If the associations described are causal, then cyclists on a long-distance ride may be able to decrease the risk of erectile dysfunction by riding a road bicycle instead of a mountain bicycle, keeping handlebar height lower than saddle height and using a saddle without a cutout if perineal numbness is experienced.
  
  
• Editorial Comment
  Although bicycle seats are now commonly sold with labels that purport preserving sexual function and “Urologist approved”, the data is inconsistent as if different shaped seats (grooved, cut-out) can prevent urethral stricture or erectile dysfunction. In fact, contrary to other studies, Dettori et al. found no association with saddle tilt, width or padding and impotence. Overall, the above study is nicely designed and executed, yet is weakened by a small cohort size of impotent bicyclists and a high non-responder rate (> 20%). Regardless they found a strong association between transient impotence and perineal numbness, riding with an “upright” posture and impotence. Such complications seem to be logical consequences of pudendal nerve and arterial compression as the course through Alcock’s canal and medial to the inferior pubic ramus. Further evidence of arterial compromise is penile transcutaneous oxygen pressure studies in long distance bicyclists, which have shown decreased penis glans perfusion while seated on a saddle.
  Although bicycling is an excellent non-impact aerobic exercise, aside from impotence, there are numerous other potential GU complications. In a recent review article, Leibovitch & Mor (1), reviewed the published literature on the common side effects of bicycling as pudendal nerve entrapment syndrome, erectile dysfunction, priapism, hematuria, prostatitis, elevated PSA, perineal folliculitis, and subcutaneous perineal nodules/ induration. Repetitive trauma complications differ from straddle injuries to the bicycle bar, where the bulbar urethra can be damaged by a crush injury against the pubic bone. In such cases, a mid bulbar, short and single stricture typically develops.

Reference
1. Leibovitch I, Mor Y: The vicious cycling: bicycling related urogenital disorders, Eur Urol. 2005; 47:277-86.

Dr. Steven B. Brandes
Associate Professor, Division of Urologic Surgery
Washington University in St. Louis
St. Louis, Missouri, USA