Racial differences in tendon rupture incidence

Despite some anecdotal evidence, the racial differences in tendon injuries have received little attention in the literature. We sought to determine the effect of race on major tendon injuries. A search was performed according to the International Classification of Diseases, Ninth Revision, Clinical Modification code 727.65 (rupture of quadriceps tendon), 727.66 (rupture of patellar tendon), and 727.67 (rupture of Achilles tendon) using the U.S. Defense Medical Epidemiology Database (DMED). Multivariate poisson regression was used to estimate the rate of major tendon rupture per 1000 person-years, while controlling for differences in gender, service, rank, and age for each code. We computed rate ratios and 95% confidence intervals using whites as the referent category. The adjusted rate ratio for black service members when compared to white service members was 2.89 (95% Cl 2.42, 3.44) for quadriceps tendon tears, 4.52 (95% Cl 3.94, 5.19) for patellar tendon tears, and 3.58 (95% CI 3.31, 3.88) for Achilles tendon tears. There appears to be a significant relative predisposition toward lower-extremity major tendon rupture in black U.S. service members when compared to white service members. Investigation of the racial differences in risk factors is warranted.