The seasonal variation of Achilles tendon ruptures in Vancouver, Canada: a retrospective study

OBJECTIVE To examine the seasonal distribution of tendon ruptures in a large cohort of patients from Vancouver, Canada. DESIGN Retrospective chart review. SETTING Acute Achilles tendon rupture cases that occurred from 1987 to 2010 at an academic hospital in Vancouver, Canada. Information was extracted from an orthopaedic database. PARTICIPANTS No direct contact was made with the participants. The following information was extracted from the OrthoTrauma database: age, sex, date of injury and season (winter, spring, summer and autumn), date of surgery if date of injury was unknown and type of injury (sport related or non-sport related/unspecified). Only acute Achilles tendon rupture cases were included; chronic cases were excluded along with those that were conservatively managed. PRIMARY AND SECONDARY OUTCOMES The primary outcome was to determine the seasonal pattern of Achilles tendon rupture. Secondary outcomes, such as differences in gender and mechanism of sport (non-sport vs sport related), were also assessed. RESULTS There were 543 cases in total; 83% of the cases were men (average age 39.3) and 17% were women (average age 37.3). In total, 76% of cases were specified as sport related. The distribution of injuries varied significantly across seasons (χ(2), p<0.05), with significantly more cases occurring in spring. The increase in the number of cases in spring was due to sport-related injuries, whereas non-sport-related cases were distributed evenly throughout the year. CONCLUSIONS The seasonality of sport-related Achilles tendon ruptures should be considered when developing preventive strategies and when timing their delivery.