Anatomical and hormonal differences may be to blame, but there are ways
to help reduce the risk.
More recent research has indicated what we orthopedic surgeons have often
seen in our practice: women are 2 to 9 times more likely than men to have
certain kinds of knee problems. Generally, knee injuries are very common,
especially for anyone who plays sports, and they can affect any of the
ligaments, tendons, cartilage, menisci, or bones surrounding the knee
joint. The complexity of the knee joint and the fact that it is a weight-bearing
joint add to its fragility and tendency for injury. Female athletes specifically
hold an average of 3.5 times the risk of injuring their ACL, a strong
elastic band that stabilizes the knee and one of the most formidable injuries
in the sports world. ACL tears can have serious consequences and are often
seen as “season-ending” injuries as full rehabilitation can
take as long as 6-9 months and may result in the athlete being unable
to play at the prior skill and intensity levels, which can be psychologically
tough on the player. Alongside developing gold standards for treating
these injuries, our focus is also aimed at
preventing them before they happen. To do this, we have to understand WHY female
knees are getting injured at higher rates than those of their male counterparts.
In studying what makes women more susceptible, researchers have surmised
that anatomy, hormones, and technique may be to blame. For one, women
have a proportionally wider pelvis than men, which causes their thigh
bones to attach at more of an angle from the hip to the knee, as compared
to men with a narrower pelvis that allows the thigh bones to attach more
vertically. This slight angle of attachment, though minimal, can cause
greater stress and instability of the knee. And then there’s estrogen,
the female reproductive hormone that is responsible for many changes in
the female body. Monthly fluctuations of estrogen have shown to influence
knee injuries, and studies indicate that female athletes are more likely
to sustain an ACL tear just before they ovulate when estrogen levels are
rising. A University of Texas case-control study found that teenage girls
from 15-19 on oral contraceptives (which lower and maintain estrogen levels)
had fewer ACL reconstructions than non-users, leading to a further belief
that estrogen does, in fact, play a role. In addition, testosterone, the
male reproductive hormone, was suggested to contribute to the ACL’s
ability to withstand greater loads, and can also help explain the different
injury rates between males and females.
As far as technique goes, females generally have different neuromuscular
control and tend to land on their feet differently than men when running
or jumping. Seeing as most ACL injuries occur during landing from a jump,
this can serve as one of the biggest risk factors. Simply put, females
tend to land from jumps in a more erect position than men, keeping their
legs straighter and requiring the knee to absorb a shock level it is not
designed to hold. Landing with the knees too straight skyrockets the stress
load of the knee and its surrounding soft tissues up to four times that
of the athlete’s weight, and by simply bending the knees an appropriate
amount, that stress can be reduced by 25%. Female athletes also characteristically
develop stronger quadriceps muscles relative to their hamstrings, an imbalance
of power that can strain the ACL. The causes of these habits could be
genetic, a result of the training they are receiving, or a combination of both.
While females can’t change their anatomy or choose their hormones,
the good news is that they CAN train to alter their body mechanics with
specialized programs. The Prevent Injury and Enhance Performance Program
(PEP) is a training program for athletes that have been able to effectively
reduce the ACL injury rate and also improve dangerous neuromuscular movement
patterns in female athletes. The program focuses on strengthening the
hip and leg muscles, particularly the weaker hamstrings muscles, practicing
proper jumping techniques, learning to land with knees more bent, as well
as overall balance, agility, and plyometrics. Ideally, the PEP program
should be started at the onset of puberty to prevent the maladaptive neuromuscular
habits from developing in the first place, but can still be just as effective
in later years. The PEP program is so effective in reducing the occurrence
of ACL injury because the training is designed to target the specifics
in female anatomy and body mechanics that directly lead to injury.
I encourage every female athlete to educate herself on best practices for
body mechanics and most importantly, to dedicate the time to participate
in a training program like PEP that can enhance and safeguard body movements
while simultaneously enhancing sports performance, so that knee injuries
won’t sideline you from the active lifestyle you love.
Sources:
https://www.webmd.com/pain-management/knee-pain/women-avoid-knee-injury
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3702781/
https://medicalxpress.com/news/2018-03-scientifically-proven-decrease-acl-injury.html