Background Elbow ulnar collateral ligament (UCL) injuries are common injuries in adolescent athletes, particularly overhead athletes. Surgical UCL incidence and outcomes are well-researched, but non-surgical UCL injury patterns and management in developing athletes are not clear.

Objective To determine patterns of UCL injuries among competitive athletes aged 11–22 years. We hypothesized that non-surgical UCL injuries occurred more frequently in younger athletes during the time frame of 2000–2016.

Design Descriptive epidemiological study.

Setting Academic, tertiary medical center.

Patients (or Participants) Electronic medical records and key word searches were used to identify patients with UCL injuries sustained during competitive athletics (N=136).

Interventions (or Assessment of Risk Factors) Age, time of injury by year, sport classification, sex.

Main Outcome Measurements UCL injuries and severity; injury management (surgical, non-surgical).

Results There were 53 surgical and 83 non-surgical UCL injuries. Non-surgical cases increased nine-fold from 2009–2016 compared to 2000–2008. Injury distribution was as follows: 60 sprains, 39 partial tears, 36 ruptures, 1 re-rupture. 92% of sprains did not undergo surgical intervention, whereas 51% of partial tears and 78% of ruptures underwent UCL-Reconstruction (UCL-R). There are increasing numbers of UCL injuries with increasing age; X² (4,136)=14.209, p=0.007. Non-surgical UCL injuries occurred in highest frequency in the youngest athletes (100% of total injuries in 11–13 years; 71.4% of 14–16 years; 44.3% of 17–22 years). UCL injury volume was most commonly associated with the sports baseball (OR 1.55, p=0.32; 95% CI 0.69–3.51), softball (OR 0.76, P=0.76, 95% CI 0.22 to 2.68), American football (OR 0.50, p=0.48; 95% CI 0.10–2.59, and javelin (OR 6.69, p=0.07; 95% CI 0.72–61.62).

Conclusions Younger athletes are sustaining more frequent, less severe UCL injuries. Enforcement of appropriate rest, proper sport-related mechanics and diversifying sport participation are important to prevent a) UCL injury at a young age, and b) progression of a non-surgical injury to a potential UCL-R.