This complicated joint is vulnerable to ligament tears, especially among women.
by Linda Melone, CSCS
Active and fit, yoga teacher Barbara Spies Blair, 59, looked forward to hiking in the White Mountains of New Hampshire. Wearing a heavy backpack, she didn’t hesitate to follow her friend, who easily hopped from boulder to boulder to cross a stream. Only Blair didn’t make the leap as successfully.
“I followed him, made a jump and immediately tore my ACL,” says Blair, referring to the anterior cruciate ligament, a knee stabilizer. Today, more than three years after surgery to repair her knee, the Babson Park, Massachusetts, resident is back to a lifestyle of hiking, biking and other sports. She credits her recovery to physical therapy combined with yoga.
Blair isn’t alone. The knee may be the body’s largest joint, but it’s also one of the most vulnerable. Unlike the shoulder joint, which moves in circles, the knee moves only forward and back with little side-to-side motion, thanks to strong stabilizers including the ACL. One wrong step (such as Blair made when she jumped from the rock) or a sudden hit on the side of the knee can easily tear these stabilizing elements.
Female Knees at Risk
Woman are prone to knee injuries for “several reasons, including the structure of a woman’s pelvis,” says Carlos Prietto, MD, CEO of Hoag Orthopedic Institute in Irvine, California. A woman’s wider hips increase the angle of the hip to the knee, known as the Q-angle (for quadriceps, the main muscle in the front of the thigh), which makes the knee less stable.
“ACL tears generally occur with jumping and landing,” says Prietto. “Volleyball, basketball and jumping, or stopping and twisting suddenly, can do it. On the other hand, you won’t normally tear your ACL walking or running straight ahead, swimming or biking.”
Women tend to be more “quad dominant,” says C. David Geier, Jr., MD, assistant professor of orthopedic surgery at the Medical University of South Carolina, “while men tend to have more equal strength in both their quadriceps and hamstrings.” Strength imbalances between these muscles can increase injury risk. Other common knee injuries include tears of the medial collateral ligament (MCL) from a direct blow to the knee and torn cartilage, which refers to the shock-absorbing material that helps protect the joint.
Trying to keep up with their active children can lead to female knee injuries. “I see a spike in ACL tears in women in their 40s, when they start skiing with their kids,” says Robert G. Marx, MD, orthopedic surgeon for the Hospital for Special Surgery in New York City and author of The ACL Solution (demosHealth). “Every part of the body gets weaker with age, and the ACL is no exception.” In addition, a partial tear earlier in life predisposes you to a complete tear later in life. The earlier tear may not have required surgery at that time, but it creates instability and could lead to arthritis as you age, says Marx.
Hormones that fluctuate with the menstrual cycle, including estrogen, progesterone and relaxin, may also play a role in female knee injuries by increasing the laxity of the ligaments, says Sara Gottfried, MD, OB/GYN, of Berkley, California, and author of The Hormone Cure (Simon & Schuster). “This fluctuation stretches out the ligaments so they’re not as tight as a man’s, making the joint less stable.”
The specific phases of the menstrual cycle and the effect on knee laxity varies with the individual, according to studies in the British Journal of Sports Medicine and The American Journal of Sports Medicine. While some study participants showed greatest laxity during the ovulation phase, others showed greater laxity at other phases.
Research has shown that women are two to eight times more likely to become injured than men.
A proactive approach to avoiding knee injuries includes exercises designed to support the core and hips. “Exercises that strengthen the muscles around the knee can help,” suggests Marx. “Women involved in jumping sports should practice jumping and landing properly to avoid twisting the knee; balance exercises can also help.” Marx also recommends warming up thoroughly prior to an exercise session, especially before playing a sport that involves sprinting or jumping.
Marx suggests performing core exercises such as the plank and side plank several times a week. To do the plank, position yourself on your hands and knees, shoulders directly over the wrists, and extend your legs behind you until your body is parallel to the floor. Engage your core by drawing your stomach back and up towards your spine, and hold. Start with 20 seconds and work up to 60 seconds.
Blair, a yoga instructor, credits doing 30 minutes of standing yoga poses every day for helping to strengthen her knee after surgery. “All standing yoga poses are good, including the triangle and warrior I and II, the side angle pose and seated squats.” She also believes taking calcium, vitamin D, magnesium and flax seed oil helped speed her recovery.
To help keep hormones in balance, particularly among premenopausal women at risk for ACL tears, Gottfried suggests avoiding coffee and all caffeine, including that found in regular tea and chocolate. She observes that both coffee and caffeine lower estradiol (a hormone in the the estrogen family) levels in premenopausal women. Choose herbal tea instead. Gottfried also recommends eating more whole soy, which is shown to reduce symptoms of low estrogen, and flaxseeds, which contain estrogen-like substances and those that act as antioxidants.
The benefits of regular exercise far outweigh the drawbacks, including the possibility of knee injuries. Taking some simple precautions can help keep athletes, especially female ones, up and active.
Doing a Side Plank
According to the American Council on Exercise (www.acefitness.org), this is how you perform the side plank mentioned in the story.
Step 1: Lie on your right side on an exercise mat with your legs straight and the left leg directly on top of the right. Bend the right elbow and place directly under your shoulder.
Align your head with your spine and keep your hips and right knee in contact with the mat.
Step 2: Exhale, keeping your abdominal muscles engaged to brace your spine, and lift your hips and knees off the mat (the side of your right foot stays in contact). Keep your head aligned with your spine and your right elbow directly under your shoulder.
Step 3: Inhale and gently return to your starting position. After doing the number of reps you want, repeat on the other side.
You can increase the intensity increasing the length of time you are in the raised position, raising the upper leg off the lower leg (parallel with the floor) or raising the lower leg off the floor and maintaining contact with your elbow and the foot of the upper leg only.