Shoulder dislocations among high school-aged and college-aged athletes in the United States: an epidemiologic analysis.

Hypothesis/Background:
Shoulder dislocations are common orthopedic injuries due to the mobile nature of the glenohumeral joint. High school and collegiate athletes are at particularly high risk for sustaining a dislocation event. Despite the prevalence of these injuries, there is a paucity in the literature regarding incidence of sports-related shoulder dislocations and mechanism of injury within these populations. Therefore, the aim of the present study was to (1) determine the incidence rate of shoulder dislocations in high school-aged and collegiate-aged athletes presenting to emergency departments (EDs) in the United States; (2) to determine the most common sports associated with shoulder dislocations; and (3) to compare the current rates and risk factors for shoulder dislocation with previous trends.

Methods:
The National Electronic Injury Surveillance System is a statistically validated injury surveillance system that collects data from ED visits as a representative probability sample of hospitals in the United States. We queried the National Electronic Injury Surveillance System for the years 2015-2019 to examine the following variables for sports-related shoulder dislocations: patient age (high school = 13-17 years of age; collegiate = 18-23 years of age), sex, year of admission, and sport type. Using a weighted multiplier, annual incidence rates were estimated based on the US Census estimates and injury rates were compared by sex and age group across the study period.

Results:
From 2015 to 2019, there were a total of 1329 athletic-related shoulder dislocations that presented to participating EDs. Of these, 698 (52.5%) shoulder dislocations occurred in collegiate athletes, while 631 (47.5%) occurred in high school athletes. Using weighted and adjusted estimates automatically generated by the National Electronic Injury Surveillance System database, this translates to 89,511 total athletic-related shoulder dislocations across the United States (95% confidence interval lower bound 68,224; 95% confidence interval upper bound 110,798). Male athletes demonstrated a higher proportion of shoulder dislocations (87%) than female athletes (13%). The most common sport-specific mechanisms of traumatic shoulder dislocation were basketball (24.1%), football (21%), soccer (7.1%), baseball (7.1%), and weightlifting (3.3%).

Conclusion:
Sports-related shoulder dislocations are frequent in high school-aged and college-aged athletes presenting to the ED. Interventions to reduce incidence of injury should be sport-specific and focus on those participating in contact and noncontact sports. Male athletes have disproportionately higher rates of dislocation. These findings are consistent with the previous epidemiologic trends in the literature that have examined the incidence of shoulder dislocations in this population.