Distal biceps tendon ruptures: incidence, demographics, and the effect of smoking.

The purpose of the current study was to determine the incidence of distal biceps tendon ruptures within a defined population, to describe the demographics of affected individuals, and to identify potential risk factors. The healthcare system in this study provides care to a known number of members in an area defined by zip codes and proximity to the medical center. Medical records for all members who presented with injuries about the elbow during a 5-year period were reviewed. Thirteen men and one woman with an average age of 47 years comprised the study population. The dominant extremity was involved in 86% of patients. All patients described a mechanism involving excessive eccentric tension as the arm was forced from a flexed position. The incidence of injury in the membership population averaged 1.2 ruptures per 100,000 patients per year. Forty-three percent reported regular tobacco use, whereas only 9% of all members were smokers. A Poisson regression analysis revealed a 7.5 times greater risk of distal biceps tendon rupture in patients who smoke. The incidence of distal biceps tendon ruptures is 1.2 per 100,000 patients, with the majority in the dominant elbow of men who smoke and who are in their fourth decade of life.