By Abby Spellings
If you are relatively familiar with sports, there is a high probability that you have encountered an ACL tear at some point in your life, whether it was your favorite athlete, your teammate, or even yourself. The anterior cruciate ligament (ACL) is located within your knee with the purpose of stabilizing the joint and aids in changing direction. ACL tears have grown into an epidemic in the athletic community, notorious for their severity and lengthy recovery time. A notable factor of this injury, though, is that it is predominantly more common in women than it is men, especially in sports like soccer, basketball, and volleyball. This essay investigates and determines the specific factors that explain why women are more likely to sustain this injury than their male counterparts using two studies from the Orthopaedic Journal of Sports Medicine. These studies offer insight into the anatomical layout of a man’s knee versus a women’s as well as how the different sexes recover after an ACL reconstruction.
The significant difference between the rate of which women tear their ACL compared to men is a major motivator for researchers to analyze this specific ligament. When investigating the difference between the ACL of a man versus a woman, the first thing that is analyzed is the anatomical structure of the joint and the way that both sexes support the weight of their bodies. In a 2021 study published by the Orthopaedic Journal of Sports Medicine (Barnett, 2021), researchers aimed to investigate the sex-based differences in the ACL tissue quality and the association between ACL size and anatomy. They hypothesized that women have smaller ACL’s and a greater ACL signal intensity in comparison to men. The study included 108 participants across two clinical trials. They used MRI (magnetic resonance imaging) scans as well as independent t tests to compare the ACL parameters between sexes. They also investigated if age, activity levels, body size, knee size, and knee anatomy had a dramatic impact on the prevalence of this injury. BMI, bicondylar width, intercondylar notch width, and posterior slope of the lateral tibial plateau were also taken into consideration to determine the individual factors that went into the functionality of the ACL and its protection against injury. The primary conclusion of this study was that there is a heavy association between the intercondylar notch size and overall ACL size, which often alludes to the higher risk for a secondary injury for smaller ACL’s due to the lack of resistance. Women had a smaller ACL cross-sectional area but that there was no significant difference between ACL volume or normalized signal intensity between men and women. These sex-based differences, however, remained significant even after adjusting for BMI and knee size based on the different sexes. The secondary finding was the relationship between the lateral tibial slope and ACL size. When a steeper lateral tibial slope is paired with a shorter ACL, a higher probability of injury is recorded, and this pairing is found predominantly in women. Overall, this study focused heavily on the size of ACL in men versus women and offers an anatomical explanation for the heightened popularity of this injury in women versus men.
Many studies have focused on investigating the recovery methods of an ACL surgery and how the different sexes respond to it. Another 2021 article published by the Orthopaedic Journal of Sports Medicine (Maguire, 2021) compares the recovery between adolescent female and male athletes. All the athletes in this study were between the ages of twelve and nineteen with closed or closing growth plates and underwent an ACL reconstruction with a hamstring autograft. Researchers hypothesized significant differences between men and women in strength, balance, and function based on the recovery patterns. The methods of this experiment evaluated the difference between the strength and functional testing between five- and eight-months post-surgery and compared the results between the two groups. They noted any of the athletes who recorded previous surgeries or any other lower body injury. They also compared limb symmetry as well as incorporating functional hop test performance and was adjusted to accommodate for the differences in physical characteristics between the two sexes. Both groups of participants demonstrated significant hamstring deficits due to the hamstring autograft that was used in the surgical reconstruction but recorded drastically different levels of quadricep strength. The female participants demonstrated a much higher deficit in the quadricep due to the way that they carry weight differently than the males. This study was performed in a hospital and used adolescent athletes that all underwent ACL reconstruction with hamstring autograft between May 2014 and May 2018. They analyzed the strength and functional testing of the patients at various points in their recovery process. Some of the limitations that they encountered was the fact that all the patients had their surgeries done by different surgeons nonconsecutively. Another limitation was the different interpretations of rehabilitation methods used by the various physical therapy each patient received. They also were unable to compare preoperative strength between the different patient groups to the post-recovery strength deficits that were recorded. These limitations were all listed by the researchers in this study. If this study had been done differently, I would suggest that they collected records from patients from the same surgeon with no earlier knee related surgeries. I also would suggest that they use similar rehabilitation methods to ensure an identical recovery process. Its limitations take away from the overall validity of the study, but it is still a useful source that works to support the overall claim that women are more likely to sustain an ACL tear than men on an anatomical level, similar to the earlier study.
ACL tears are continuously on the rise in the athletic community, specifically in females. The number of athletes who are being sidelined or forced into retirement because of this injury is rising at alarming rates, prompting researchers to investigate the reasoning for this. These two studies are vital to understanding the sex-based differences concerning the rate of ACL tears between men and women, as well as working towards developing new prevention methods for both youth and adult sports. By conducting these studies, we are able develop prevention methods to protect athletes from sustaining this dramatic injury and prevent further damage to the knee joint.
BIBLIOGRAPHY
– Barnett, Samuel C., Martha M. Murray, Sean W. Flannery, Danilo Menghini, Braden C. Fleming, Ata M. Kiapour, Benedikt Proffen, et al. ACL Size, but Not Signal Intensity, Is Influenced by Sex, Body Size, and Knee Anatomy. Orthopaedic Journal of Sports Medicine. 9(12) (2021): 232596712110638. https://doi.org/10.1177/23259671211063836
– Maguire, K., Sugimoto, D., J. Micheli, L., S. Kocher, M., and E. Heyworth, B., 2021. Recovery after ACL Reconstruction in Male versus Female Adolescents: A Matched, Sex-Based Cohort Analysis of 543 Patients. Orthopaedic Journal of Sports Medicine. 9.(11) (2021): 232596712110548. https://doi.org/10.1177/23259671211054804
Featured Image Citation:
Photograph. n.d.Asian woman patient with bandage compression knee brace support injury on the bed in nursing hospital.healthcare and medical support..