Non-contact Anterior Cruciate Ligament Injury Epidemiology in Team-Ball Sports: A Systematic Review with Meta-analysis by Sex, Age, Sport, Participation Level, and Exposure Type.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational cohort studies
PubMed 35622227 · doi:10.1007/s40279-022-01697-w
What was done
Six databases (MEDLINE, EMBASE, Web of Science, CINAHL, Scopus, and SPORTDiscus) were searched through July 2021. The authors conducted a systematic review and meta-analysis of cohort studies in team ball-sports that reported knee injury counts as a function of exposure and injury mechanism (contact vs. non-contact). Pooled estimates were stratified by sex, age, sport, participation level, and exposure type (competition vs. training).
What was found
Forty-five studies covering 13 sports were included. Non-contact injuries accounted for 55% of total ACL injuries (95% CI 48–62%, I² = 82%), with higher proportions in females (63%, 95% CI 53–71%, I² = 84%) than males (50%, 95% CI 42–58%, I² = 86%). Overall non-contact ACL incidence was 0.07 per 1,000 player-hours (95% CI 0.05–0.10, I² = 77%) and 0.05 per 1,000 player-exposures (95% CI 0.03–0.07, I² = 97%). Injury incidence per 1,000 player-hours was significantly higher in females (0.14, 95% CI 0.10–0.19) than males (0.05, 95% CI 0.03–0.07), and substantially higher during competition (0.48, 95% CI 0.32–0.72) than training (0.04, 95% CI 0.02–0.07).
Why it matters
Because more than half of team-sport ACL injuries occur without direct contact, targeted neuromuscular and biomechanical risk-reduction programs address the predominant injury mechanism, especially for female athletes and match play.
Limits
Statistical heterogeneity was high across most pooled analyses (I² up to 97%). The abstract does not report the total athlete count, individual athlete characteristics, or specific breakdown by age and participation level. Included observational studies may vary in how exposure hours and non-contact mechanisms were classified.
Cited by
- supports Women are more susceptible to ACL injuries than men.