TABLE 2.

First-Time Noncontact ACL Injury Rates and Relative Risks Associated With Sex, Level of Play, and Sport^a

	Person-Days of Exposure	No. of ACL Injuries	Injury Rate per 1000 Person-Days	95% CI	Relative Risk (Adjusted)	95% CI
Sex
Males	668,780	42	0.063	0.045–0.085	1.00
Females	524,996	59	0.112	0.086–0.145	2.10	1.34–3.27
Level of play
High school	873,057	53	0.061	0.045–0.079	1.00
College	320,719	48	0.150	0.110–0.198	2.38	1.55–3.64
Sport
Soccer	289,573	35	0.121	0.084–0.168	1.77	1.04–3.01
Basketball	280,727	17	0.061	0.035–0.097	0.84	0.45–1.57
Lacrosse	317,041	23	0.073	0.046–0.109	1.00
Field hockey	108,939	5	0.046	0.015–0.107	0.47	0.18–1.27
Football	162,650	11	0.068	0.034–0.121	1.68	0.78–3.63
Rugby	32,609	9	0.276	0.126–0.524	2.23	1.01–4.94
Volleyball	2237	1	0.447	0.011–2.491	2.57	0.34–19.38

^aACL, anterior cruciate ligament.