Epidemiology of lateral ankle sprain focusing on indirect contact mechanism in male and female soccer players: An 18.5-month cohort study.

Background: Epidemiological research highlights the need to understand sports injuries for effective prevention. Yet, detailed knowledge about lateral ankle sprain (LAS) in soccer, especially related to indirect contact mechanisms and specific sports movements, remains scarce. This study aimed to determine the prevalence of LAS by examining injury mechanisms, focusing on indirect contact, and analyzing sports-related movements.

Study Design: Prospective study.

Methods: In this prospective study, 304 high-school and college soccer players (age: 19.0 ± 2.2 years, height: 168.3 ± 10.6 cm, weight: 64.2 ± 11.1 kg) were monitored for 18.5 months. Attendance and LAS incidents were recorded daily. Injury details, including movement at the time of injury, contact presence, and direction, were collected through interviews conducted on the injury day. LAS were categorized into direct contact, indirect contact, and non-contact mechanisms. Direct contact injuries were due to external forces on the lower leg or foot. Indirect contact injuries resulted from impacts on areas other than the lower leg or foot, and non-contact injuries involved no interaction with the ball or opponent. Incidence rates per 1,000 athlete exposures and 95 % confidence intervals (CIs) were calculated, along with rate ratios (RR) to assess sex differences.

Results: The study recorded 59 LAS injuries. Indirect injuries were predominant, accounting for 47.5 % (n = 28) of the cases. Men experienced a higher incidence of indirect injuries, with an RR of 2.29 (95 % CI: 1.06-4.96). Outward contact was the most common (77.8 %; n = 21), while inward contact occurred in 22.2 % of the cases (n = 6).

Conclusion: High school and college soccer players primarily sustained injuries through indirect contact mechanisms, with a significant number of injuries occurring during lateral contact. Men were more prone to indirect contact injuries. Furthermore, 47.5 % of LAS incidents involved reactive movements, and injuries frequently occurred during specific sports actions, such as ball interception.