It’s no surprise that men and women have different health issues, but it might surprise you that the need for knee replacement surgery falls heavily in the women’s column. In fact, women undergo this procedure at a rate of 45.6% higher than men.
Dr. Bryan King and Dr. Jeffrey Cuomo, our experienced surgeons at Tuscaloosa Orthopedic & Joint Institute in Tuscaloosa, Alabama, explain why.
The science behind women’s high rate of knee replacement
Knee pain is common and unsurprising given this weight-bearing joint's constant use, overuse, and abuse. It often stems from injuries due to falls, sports, or auto accidents, but the most common culprit is arthritis — osteoarthritis specifically.
Our team offers many conservative treatments to address knee pain, including total knee replacement surgery, but only as a last resort. When surgical intervention becomes necessary, we find that women need it more often than men, and here’s why.
Female Knee Anatomy and biomechanics
- The knee is a complex joint formed by the end of the femur (thigh bone), the top of the tibia (shin bone), and the patella (kneecap). These bones are cushioned by cartilage, a firm, rubbery substance that reduces friction and allows smooth motion.
- Ligaments and tendons connect the bones and muscles, providing stability and flexibility.
- Women and men share the same basic knee anatomy, but gender-specific differences in knee biomechanics can influence the likelihood of injury and joint degeneration.
- Women, for instance, have a wider pelvis, which results in a greater angle between the thigh and shin bones (known as the Q-angle). This anatomical difference places additional stress on a woman's knee, making it more prone to injury and wear and tear.
More prone to osteoarthritis
Osteoarthritis — the breakdown of cartilage in the joints — can affect anyone, but women experience this debilitating condition 40% more often than men. Since osteoarthritis is the main driver for knee replacement surgery, this stat explains why more women than men come in for this procedure.
However, osteoarthritis isn’t the only culprit. Here are several other factors that exacerbate the problem for women.
Previous knee trauma
- Women are more susceptible to certain knee injuries, particularly those involving the anterior cruciate ligament (ACL). Tears of the ACL are often the result of sudden stops or changes in direction, common in sports like soccer or basketball.
- Once damaged, your knee joint may never fully recover, and over time, repeated trauma can lead to osteoarthritis and the need for a knee replacement.
- Joint laxity refers to the looseness or flexibility of the ligaments surrounding your knee. Women tend to have greater joint laxity than men. More laxity makes you more flexible, which can come in handy during some activities but can also lead to joint instability.
- This instability places extra stress on your knee's cartilage, accelerating the wear and tear and increasing your risk of osteoarthritis and subsequent knee replacement.
Hormonal and menopausal factors
- Women's hormones play a significant role in joint health. Estrogen, for example, has a protective effect on cartilage. However, during menopause, estrogen levels drop sharply, reducing this protective influence and leading to increased cartilage breakdown.
- The onset of menopause often coincides with a period of rapid joint degeneration, further contributing to the higher prevalence of knee replacements among women.
If you have chronic knee pain, contact Tuscaloosa Orthopedic & Joint Institute to find out what’s causing it and how to avoid knee replacement surgery.