Humana HealthBeat Transcript Archive

Sports injuries affect 100s of thousands of Americans each year. Perhaps because of the popularity of women's pro teams, more young girls are playing soccer and basketball, so the injury rate is up-and girls are at more risk than the guys when it comes to ACL injuries.

ACL stands for anterior cruciate ligament. It's a strong band of tissue that runs diagonally from the front of the shinbone to the back of the thighbone. It makes the knee more stable by limiting the rotation and forward movement of the shinbone.

The ACL can get injured by being stretched, torn, or twisted. Women seem to be at greatest risk, with a rate of injury four to eight times that of men. A number of factors may contribute to this problem.

Women have a much smaller knee joint surface than men, which may make us more susceptible to injury. Our wider hips may place greater pressure on the inside of the knee.

Hormonal influences may also be at work. Studies have shown that women may suffer more injuries during the time of the cycle that coincides with ovulation and higher estrogen levels. One study showed that when estrogen was added to fibroblasts, the cells that produce collagen, which forms the ligament tissue, the fibroblasts grew at a lower rate in the first three days of the experiment and that growth slowed in the presence of more estrogen. This effect declined as the experiment continued.

Female athletes also tend to use their muscles differently than men. Women tend to rely on their quadricep muscles at the front of the thigh, rather than their hamstring muscles at the back of the thigh, which men are more likely to use. During a jump, women tend to land in a straighter position, which exposes the knee joint to more force, and makes the ACL more prone to tearing.

Knee injuries can be prevented by warming up the muscles prior to exercising, strengthening leg muscles, and wearing shoes that fit properly and are in good condition. A study presented at last year's annual meeting of the American Academy of Orthopaedic Surgeons suggested that bending and crouching while running may reduce the risk of knee injury. I would also suggest talking to athletic coaches to make sure that training is appropriate for girls.

February 16
ACL and Women
	Sports injuries affect 100s of thousands of Americans each year. Perhaps because of the popularity of women's pro teams, more young girls are playing soccer and basketball, so the injury rate is up-and girls are at more risk than the guys when it comes to ACL injuries. ACL stands for anterior cruciate ligament. It's a strong band of tissue that runs diagonally from the front of the shinbone to the back of the thighbone. It makes the knee more stable by limiting the rotation and forward movement of the shinbone. The ACL can get injured by being stretched, torn, or twisted. Women seem to be at greatest risk, with a rate of injury four to eight times that of men. A number of factors may contribute to this problem. Women have a much smaller knee joint surface than men, which may make us more susceptible to injury. Our wider hips may place greater pressure on the inside of the knee. Hormonal influences may also be at work. Studies have shown that women may suffer more injuries during the time of the cycle that coincides with ovulation and higher estrogen levels. One study showed that when estrogen was added to fibroblasts, the cells that produce collagen, which forms the ligament tissue, the fibroblasts grew at a lower rate in the first three days of the experiment and that growth slowed in the presence of more estrogen. This effect declined as the experiment continued. Female athletes also tend to use their muscles differently than men. Women tend to rely on their quadricep muscles at the front of the thigh, rather than their hamstring muscles at the back of the thigh, which men are more likely to use. During a jump, women tend to land in a straighter position, which exposes the knee joint to more force, and makes the ACL more prone to tearing. Knee injuries can be prevented by warming up the muscles prior to exercising, strengthening leg muscles, and wearing shoes that fit properly and are in good condition. A study presented at last year's annual meeting of the American Academy of Orthopaedic Surgeons suggested that bending and crouching while running may reduce the risk of knee injury. I would also suggest talking to athletic coaches to make sure that training is appropriate for girls.

	If a girl does have an ACL injury, are there any differences in treatment? No, and there doesn't appear to be any difference in results of surgical reconstruction, for example. It is important to note that exercise and rehabilitation are key factors for successful recovery, in addition to surgery. References and Resources: American Academy of Orthopaedic Surgeons www.aaos.org Knees and Tendons The National Women's Health Information Center www.4woman.gov/faq/knees.htm Questions and Answers about Knee Problems National Institute of Arthritis and Musculoskeletal Skin Diseases www.nih.gov/niams/healthinfo/kneeprobs/kneeqa.htm