By Dr. Cynthia Mangla, D.C.
As we are deep into ski and snowboarding season, we are seeing an increase in the number of knee-related injuries. Generally, anterior cruciate ligament (ACL) injuries are the most commonly seen knee injuries among athletes. In many cases these injuries can lead to long-term instability of the knee, early degenerative changes, and increased risk for re-injury. Typically, about 70% of ACL injuries are due to non-contact related causes including deceleration, landing with inadequate hip/ankle flexion, and sudden change in direction.
Interestingly, it is found that female athletes are 4-6 times more likely to endure an ACL injury. This is especially true for women who are involved in sports such as soccer, basketball volleyball and skiing. Recent studies have shown that there are a number of potential reasons why women are more susceptible to non-contact ACL injuries than their male counterparts.
ACL Size and Bone Shape
Some have hypothesized that women have a smaller ACL size, which in turn can be correlated to being weaker. In addition, the ACL runs through the femoral notch (found at the base of the femur), which tends to be narrower in females. This relationship between the ACL and femoral notch in females may lead to increased knee injuries when excessive load is placed on the femoral notch.
After females reach puberty, they tend to have increased laxity of their ligaments and other soft tissue structures. This laxity can lead to general hypermobility within the joints. It was also found that those who suffer from ACL injuries typically have more laxity in their hamstrings, which leads to a delay in hamstring activation and decrease in dynamic control.
Larger “Q” Angle
One of the most hypothesized reasons for why females are more prone to ACL injuries is due to an increased quadriceps femoris muscle angle (Q angle). The reason women tend to have a larger Q angle is due to having a wider pelvis in relation to their knees. This increased Q angle found in females is believed to create greater stress on the patella.
The most important reason for differences in ACL injury rates is due to neuromuscular differences. Female athletes typically have different movement patterns during sporting events compared to males. One major reason for this is high quadriceps activation to low hamstring activation. Weak hamstrings can lead to an improper ability for the hamstrings to balance the quadriceps when contracted. This can place a higher stress on the ACL making it more susceptible to injury.
ACL Injury Prevention
Fortunately, there are a number of different measures female athletes can take in order to lower the risk of non-contact ACL injuries:
- Participating in a regular strengthening protocol for the legs, gluteus and core muscles
- Neuromuscular training thorough proprioceptive and balancing exercises
- Focusing on correct footwear and insole support for the feet
- Proper alignment of spine, pelvis, feet and ankles to improve biomechanics
Reach out to your Sports Chiropractor for guidance on all of the above.