|MadSci Network: Anatomy|
Women do appear to tear their ACLs more than men. An incidence report from several seasons ago from the ACC listed 20 ACL tears in female basketball players compared to 4 for men. A few possible reasons are: 1. The intracondylar notch of the femur in women is more narrow than in men. A women's notch is more "A" shaped while men have more "U" shaped notches. The premise here is that friction or "catching" of the ACL may contribute an additional mechanical load. 2. Dr. Frank Noyes has postulated that women have weaker hamstrings. He believes a 60-70% hamstring to quadriceps strength ratio is needed for twist/turn sports. The 60% number is often sited by physical therapists and athletic trainers. In female athletes, the ratio is reportedly 45-55%, too weak to protect the ACL. 3. Another idea is that hormonal changes throughout a woman's menstrual cycle increase ligament laxity, thereby making her more vulnerable to injury at different points in the cycle. Check out the New York Times article at: "http://search.nytimes.com/search/daily/bin/fastweb? getdoc+site+site+28425+2+wAAA+hamstrings" (All one line) The real answer, I guess, is we don't know. There are several ideas out there, but none sufficiently substantiated by the research yet. You can see by my topic search that I am biased toward the strength theory. They may all play a roll, however.
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