There are a lot of differences between men and women. Besides the obvious ones – anatomical, biological, physiological – there are some differences that may not be as apparent.
Take women’s legs, for example. The fact that women can get pregnant, carry a growing baby in their belly for nine months, and then give birth is one reason women’s legs are different than men’s. That’s because a woman’s pelvic bone is wider than a man’s – all the better to carry out these physically demanding reproductive tasks. But therein lies the reason why women suffer knee problems with greater frequency than men do.
The larger width of a woman’s hips, while permitting the bearing of children, also causes a misalignment of the knees that is not present in men.
This evolutionary adaptation that allows easier childbearing means the ring of bones that make up the pelvis – the pelvic ring – is wider in women than in men. Due to that extra width, the top of the thigh bone (femoral head) that fits into the pelvis does so at a distinctly greater angle. It’s why women may appear to be slightly knock-kneed, with the thighs curving inward from hip to knee.
This angle also causes more force to be borne by a woman’s knee joint, especially when running, jumping or landing.
Hormones like estrogen play a role in ligament health. Studies have shown that estrogen appears to weaken ligaments such as the anterior cruciate ligament (ACL) of the knee. And because women have higher levels of estrogen than men, it may be why they are more prone to ACL injuries.
In fact, research shows that women injured the ACL of their knee even more often during their menstrual cycle, when estrogen levels are at their peak. Younger women going through puberty have higher levels of estrogen, which also corresponds to more ACL knee injuries among young female athletes.
When jumping, men tend to begin a jump by using the hamstring or muscles at the back of the leg, while women tend to do the opposite – use the quadriceps or muscles at the front of the leg. Using the quads tend to stiffen the knee joint, making it less flexible and able to absorb the shock of a jump and landing.
When landing, injuries happen more often when a person lands with their knees closer together rather than spread further apart. Because of a woman’s wider hips, and greater angle of thigh to knee, they may be more likely to land from a jump with their knees closer together – and thus be more susceptible to knee injury.
Knee Injury Prevention
While men may seem to become injured far more often than women, that is primarily due to the larger percentage of men who take part in sports. If as large a percentage of women played sports, the number of injuries suffered by women would be more apparent.
Women can train to alter their gait and jump cycles to be as effective or better than men at jumping – and to do so safely, without injury. It may be as simple as a matter of conditioning.
At the end of the day, knee injuries can happen to anyone, at any time. All it takes is the wrong move at the wrong time. Women – and men – should be careful when it comes to their knees, especially during any strenuous activity.
If you have a knee issue and it has been troubling you, or if you hear and feel a “pop” on landing after a jump, it may be a problem with your anterior cruciate ligament (ACL). Contact orthopedic surgeon Dr. Brett Gilbert by calling (919) 788-8797 or request an appointment online. Whether you’re a man or woman – you don’t want to risk worsening a knee injury. Seek professional medical help.