The 15- to 45-year-old age group is at highest risk. Injuries occur primarily among active people, especially in sport involving cutting, pivoting, and decelerating (e.g., soccer, basketball, skiing) or contact (e.g., rugby). In children, falling off of a bike while trying to plant the ipsilateral foot is a common mechanism of ACL avulsion from the tibial eminence.[8]Accousti WK, Willis RB. Tibial eminence fractures. Orthop Clin North Am. 2003;34:365-75.
http://www.ncbi.nlm.nih.gov/pubmed/12974486?tool=bestpractice.com
The estimated US incidence is 100,000 to 200,000 ACL tears per year, with 100,000 ACL reconstructions per year.[9]Weitzel PP, Richmond JC, Altman GH, et al. Future direction of the treatment of ACL ruptures. Orthop Clin North Am. 2002;33:653-61.
http://www.ncbi.nlm.nih.gov/pubmed/12528907?tool=bestpractice.com
About 70% of ACL tears occur during sports activities. Based on US National Collegiate Athletic Association date from 2004 to 2013, the highest average annual rate of injury was 0.17 per 1000 athlete-exposures for men and 0.23 for women.[10]Agel J, Rockwood T, Klossner D. Collegiate ACL Injury Rates Across 15 Sports: National Collegiate Athletic Association Injury Surveillance System Data Update (2004-2005 Through 2012-2013). Clin J Sport Med. 2016 Nov;26(6):518-23.
https://www.doi.org/10.1097/JSM.0000000000000290
http://www.ncbi.nlm.nih.gov/pubmed/27315457?tool=bestpractice.com
The female-to-male ratio has generally ranged from 2:1 to 8:1, and varies across sports.[11]Hootman JM, Dick R, Agel J. Epidemiology of collegiate injuries for 15 sports: summary and recommendations for injury prevention initiatives. J Athl Train. 2007 Apr-Jun;42(2):311-9.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1941297
http://www.ncbi.nlm.nih.gov/pubmed/17710181?tool=bestpractice.com
[12]Mihata LC, Beutler AI, Boden BP. Comparing the incidence of anterior cruciate ligament injury in collegiate lacrosse, soccer, and basketball players. Am J Sports Med. 2006;34:899-904.
http://www.ncbi.nlm.nih.gov/pubmed/16567461?tool=bestpractice.com
[13]Agel J, Arendt EA, Bershadsky B. Anterior cruciate ligament injury in National Collegiate Athletic Association basketball and soccer: a 13 year review. Am J Sports Med. 2005;33:524-30.
http://www.ncbi.nlm.nih.gov/pubmed/15722283?tool=bestpractice.com
[14]Myer GD, Ford KR, Hewett TE. Methodological approaches and rationale for training to prevent anterior cruciate ligament injuries in female athletes. Scand J Med Sci Sports. 2004;14:275-85.
http://www.ncbi.nlm.nih.gov/pubmed/15387801?tool=bestpractice.com
[15]Giugliano DN, Solomon JL. ACL tears in female athletes. Phys Med Rehabil Clin N Am. 2007;18:417-38.
http://www.ncbi.nlm.nih.gov/pubmed/17678760?tool=bestpractice.com
Non- or minimal-contact injuries account for majority of ACL injuries (up to 70%), especially in females.[1]Boden BP, Dean GS, Feagin JA, et al. Mechanisms of anterior cruciate ligament injury. Orthopedics. 2000;23:573-78.
http://www.ncbi.nlm.nih.gov/pubmed/10875418?tool=bestpractice.com
[10]Agel J, Rockwood T, Klossner D. Collegiate ACL Injury Rates Across 15 Sports: National Collegiate Athletic Association Injury Surveillance System Data Update (2004-2005 Through 2012-2013). Clin J Sport Med. 2016 Nov;26(6):518-23.
https://www.doi.org/10.1097/JSM.0000000000000290
http://www.ncbi.nlm.nih.gov/pubmed/27315457?tool=bestpractice.com
[16]Ireland ML, Ott SM. Special concerns of the female athlete. Clin Sports Med. 2004;23:281-98.
http://www.ncbi.nlm.nih.gov/pubmed/15183572?tool=bestpractice.com
[17]Krosshaug T, Nakamae A, Boden BP, et al. Mechanisms of anterior cruciate ligament injury in basketball: video analysis of 39 cases. Am J Sports Med. 2007;35:359-67.
http://www.ncbi.nlm.nih.gov/pubmed/17092928?tool=bestpractice.com
One study suggests a higher rate for white European American basketball players than for non-white players.[18]Trojian TH, Collins S. The anterior cruciate ligament tear rate varies by race in professional women's basketball. Am J Sports Med. 2006;34:895-8.
http://www.ncbi.nlm.nih.gov/pubmed/16476911?tool=bestpractice.com