Shoulder Dislocations Among High School-Aged and College-Aged Athletes in the United States: Epidemiologic Analysis

Shoulder Dislocations Among High School-Aged and College-Aged Athletes in the United States: Epidemiologic Analysis

Authors: John Twomey-Kozak, BS; Keith G. Whitlock, MD; Jeff A. O’Donnell, MD; Oke A. Anakwenze, MD, MBA; Christopher S. Klifto, MD
Institution: Department of Orthopaedic Surgery, Duke University Medical Center, Durham, NC, USA
Keywords: Shoulder dislocations, Glenohumeral instability, Sports medicine, High school athletes, Collegiate athletes
Level of Evidence: Level IV; Case Series Using Large Database; Epidemiology Study

Hypothesis/Background

  • Shoulder dislocations are frequent orthopedic injuries, particularly due to the mobile nature of the glenohumeral joint.

  • High school and collegiate athletes face a heightened risk for these injuries.

  • There is limited literature examining the incidence of sports-related shoulder dislocations specifically in these populations.

  • Objective of the Study:

    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. Identify the most common sports linked with shoulder dislocations.

    3. Compare current rates and risk factors for shoulder dislocation with previous trends in literature.

Methods

  • Data Source: National Electronic Injury Surveillance System (NEISS) - a statistically validated system collecting data from ED visits representing hospitals in the United States.

  • Data Collection Period: 2015-2019.

  • Variables Analyzed: Age, sex, year of admission, and sport type for shoulder dislocations.

  • Age Definitions:

    • High school: 13-17 years

    • Collegiate: 18-23 years

  • Estimation Process: National incidence rates estimated using weighted multipliers based on U.S. Census estimates and injury rates compared by sex and age group across the study period.

Results

  • Total Cases: 1329 athletic-related shoulder dislocations from 2015 to 2019.

    • Collegiate Athletes: 698 dislocations (52.5%)

    • High School Athletes: 631 dislocations (47.5%)

  • Estimated National Dislocation Rate: 89,511 total athletic-related shoulder dislocations in the U.S. during the study period, with 95% confidence intervals ranging from 68,224 to 110,798.

  • Sex Distribution:

    • Male athletes: 87% of shoulder dislocations

    • Female athletes: 13%

  • Common Sports for Shoulder Dislocations:

    1. Basketball (24.1%)

    2. Football (21%)

    3. Soccer (7.1%)

    4. Baseball (7.1%)

    5. Weightlifting (3.3%)

Conclusion

  • High incidence rates of sports-related shoulder dislocations observed among high school-aged and college-aged athletes.

  • Proposed interventions to reduce injury incidence should be sport-specific, focusing on high-contact and non-contact sports.

  • Notable differences exist in dislocation rates between male and female athletes, consistent with prior trends.

Discussion

  • Participation in youth athletics continues to rise in the U.S., increasing the expected incidence of upper extremity sports-related injuries.

  • Shoulder dislocations account for 50% of all large joint dislocations in the United States.

  • Epidemiological Mention: Past studies highlight the prevalence of shoulder dislocations among athletes, yet the current study represents a significant contribution to understanding sport-specific mechanisms of dislocation.

  • Methodology: The retrospective analysis through NEISS offers a standardized approach to understanding injury patterns and demographics.

  • Statistical Analysis:

    • 95% confidence intervals calculated for incidence rates, with comparisons made between sexes and age groups.

    • Odds ratios computed for risk estimations between groups.

  • Trends Observed:

    • No significant difference in dislocation rates between age groups, but a notable male predominance in incidence across the board.

Limitations

  • NEISS database provides estimates based on sampled ED visits and may not reflect true population injury rates due to potential sampling bias.

  • Data only includes injuries treated in EDs, potentially missing cases managed elsewhere or those not seeking medical care.

  • Lack of comprehensive variables, such as specific mechanisms of injury, surgical interventions, or long-term outcomes, limits deeper analysis.

References

  1. National Federation of State High School Associations. 2018-19 high school athletics participation survey.

  2. Burra G, Andrews JR. Acute shoulder and elbow dislocations in the athlete. Orthop Clin North Am 2002;33:479-95.

  3. Carr JB 2nd, et al. Management of shoulder and elbow injuries in baseball athletes. Curr Rev Musculoskelet Med 2019;12:67-71.

  4. De Martino I, Rodeo SA. The Swimmer's shoulder: multi-directional instability. Curr Rev Musculoskelet Med 2018;11: 167-71.

  5. DeFroda SF, et al. Shoulder instability in women compared with men. JBJS Rev 2019;7:e10.

  6. Owens BD, et al. Incidence of glenohumeral instability in collegiate athletics. Am J Sports Med 2009;37:1750-4.

  7. Zacchilli MA, Owens BD. Epidemiology of shoulder dislocations presenting to emergency departments in the United States. J Bone Joint Surg Am 2010;92:542.