FLIPPING THE SCRIPT ON WOMEN’S ACL INJURY PREVENTION & MANAGEMENT

FEATURE / DR JOANNE L PARSONS, DR SHEREE BEKKER, DR STEPHANIE E COEN

Introduction

Despite 30 years and tens of thousands of research studies, there are still significant differences in sports injury rates between women and men. Concussion and ankle sprain rates remain twice as high in girls/ women1,2, and ruptures of the anterior cruciate ligament (ACL) – which have occurred with alarming frequency in the last year– occur up to six times more frequently than in boys/ men.3,4 Severe injuries like ACL rupture can remove athletes from play for months, result in early development of osteoarthritis5, early knee replacement6, and negatively impact lifelong physical activity participation.7 To start making tangible change, we need to steer away from the overwhelming focus on biological and sex-based explanations (e.g. anatomical characteristics, hormone levels) that are part of current sports injury approaches (Table 1), and instead seriously consider the role of the social and material environments that shape the athlete in highly gendered ways (Figure 1).8

Where are we now?

Since the first recognition of higher ACL injury rates in women in the 1990s, the search for risk factors has focused largely on sex-based explanations such as anatomy (e.g., femoral notch and ligament size; ligament laxity) and physiology (e.g., muscle strength and activation patterns; hormones/menstruation) (Table 1). These factors are largely thought of as intrinsic or internal to the athletes – in other words, they are the athlete’s responsibility to ‘fix’ (if indeed they can be ‘fixed’ at all). However, despite all the work that has occurred over the last 30 years, ACL injury rates for women at all levels of play have either increased or stayed the same4,16 Injury rates are anywhere from 2-6 times higher in women compared to men17-19

Once an ACL injury has occurred, there is some evidence that women are not offered a surgical option as often as men20. If they do have reconstructive surgery, women demonstrate greater knee laxity, lower patient reported knee function, a lower chance of returning to sport, and a more frequent need for revision surgery after their surgery, compared to men21. Again, investigations into the reasons for these disparities continue to take a sex-based biological approach.

How can we look at things differently?

Our research8 suggests that sport practitioners need to move beyond biology to consider ACL (and other sport injuries) from both social and biological viewpoints. By looking at the list of risk factors for ACL injury (Table 1) we can provide plausible explanations for how sport environments may influence risk. For example, resistance training is key to increasing strength and optimising strength ratios, but we know that girls and women often do not view resistance training and increasing muscle mass

Q angle

‘Intrinsic’ risk factors

Navicular drop

Knee valgus (static and dynamic)

Notch size

Ligament size

Tibial slope angle

Foot pronation

Body Mass Index

Body composition

Menstrual phase

Muscle strength

Hormone concentrations

Muscle strength ratios

Muscle stiffness

Physical fitness

Previous ACL injury

Skill level

Neuromuscular control

Proprioception

Personality

Sports played

Stress response

Race

Sex

Family history of ACL injury

‘Extrinsic ‘ risk factors

Meteorological conditions

Playing situation

Playing surface

Opponent behaviour

Rules

Unanticipated events during play

Referee behaviour

Coaching behaviour

Footwear

Knee braces

Women are injury prone

(e.g. women as menstrual cycles or Q-angles)

Women are made injury prone Focus largely on women’s bodies Consider social and environmental factors

(e.g. stereotypes that disadvantage women)

Marginal gains

(e.g. menstrual cycle monitoring)

Meaningful gains

(e.g. gender equitable environments) as socially acceptable due to societal norms about ‘desirable’ femininity22-25

They also experience resistance training environments as highly gendered and unwelcoming to women25. How can we say, then, that muscle strength, strength ratios, activation patterns, and physical fitness are all intrinsic risk factors when the programs and environments (i.e., gyms) required to address those factors are heavily gendered in ways that disadvantage women’s participation?

It is plausible that even anatomical characteristics (size of the ACL, shape of the femoral notch), which are recognized risk factors for ACL injury, could be influenced by external environments. The foundation of the rehabilitation and strength and conditioning professions is the principle of tissue adaptability – soft tissue and bone will adapt and remodel according to the forces placed upon them. This means that bone and ligament size and shape could conceivably be influenced by gendered environments that do not encourage women to train and compete as intensely or as often or from as early an age as men.

In the treatment environment, comparing the poorer post-surgical outcomes of women (e.g., more laxity, lower function, lower chance of returning to sport) to that of men assumes that their rehabilitation and training environments were equivalent, which we have suggested is not true. Also, it is widely known that in most parts of the world women still carry the bulk of childcare and domestic responsibilities. That means women and men very likely have different constraints on their time and ability to complete their rehabilitation programs, which will heavily influence their surgical outcomes and ability to return to play. There are numerous recent examples of how women’s resources, support, and environments are inferior to those of men. From not getting paid while on maternity leave, to relying on inadequately staffed medical teams at a professional level, to playing on sub-standard field conditions, there are constant reminders of how gendered beliefs and expectations influence the way people are treated, the opportunities they have, the activities they participate in, and ultimately their health.

How can you use these ideas to improve things in your practice now?

First – understand how sex and gender relate to each other:

> Sex refers to a complex blend of physical and physiological characteristics (e.g., hormones, genes, anatomy), while gender refers to identities, roles, and structures that are formed by society which may or may not align with sex. Neither sex nor gender is binary.26

> Sex/gender is increasingly being used as a term to recognize the ‘entanglement’ of biological and social factors in expressions of sex and gender.27 It acknowledges the dynamic processes and interactions through which “body-based characteristics…are shaped by gendered social interactions”.28

Now you can reflect on where in the following four sport environments you can intervene:

Pre-sport environment

Gendered play develops different physical skill sets, and the ability to demonstrate and control particular movement patterns are key to injury prevention. Early experiences set the stage for what girls understand as acceptable behaviors and roles.

> Encourage all children to participate in a wide range of activities, and especially encourage girls towards more active play

> Do not use phrases such as “you throw like a girl”

Training environment

Strength training environments are often not welcoming to girls and women. Girls and women are inundated with messages from society about body norms and what they ‘should’ look like.

> Evaluate whether there are gendered messages or imagery in weight-training or clinic spaces. What kind of posters or pictures do you have up, and what message are they sending, either implicitly or explicitly?

> Have a knowledgeable woman coach in weight-training spaces who can be a positive role model

> Focus on an athlete’s goals, performance gains, physical and mental health, not appearance, which is often gendered in nature when commented on

Competition environment

By its very nature, sport places girls/ women and boys/men in different playing situations. The nature and type of sports thought appropriate for women and men are often different.

> Work towards ensuring girls/women and boys/men have equal opportunity to participate in all sports at all ages

> Challenge different rules for girls/ women and boys/men that imply gendered expectations and abilities that disadvantage women (e.g., tennis matches for women are 3 sets; men are 5 sets)

Treatment environment

Gendered assumptions permeate healthcare, and sports medicine is no different. Post-ACL injury outcomes are different for women and men.

> Reflect on how you manage and treat women and men who have ruptured their ACL. Is there a difference, and can you justify it based on observations and assessments and not just assumptions?

> Ask your athlete patients about their nonsport gendered roles like childcare and unpaid work at home. How does it affect their ability to play and rehabilitate?

Conclusion

ACL injury rates have not changed in 30 years despite tens of thousands of studies. The overwhelming focus on biological explanations may be a reason for this failure. Considering gender an external environmental influence will encourage us to ask new questions and move towards improving outcomes for girls and women.

For more information on this topic, see the following resources:

1. Our open access paper

2. Podcast where we discuss our paper

3. Blog where we discuss our paper

4. Interview with Flo Lloyd-Hughes on the Counter Pressed podcast

5. Interview with Kathleen McNamee, Emma Byrne, and Karen Duggan on the COYGIG Pod

Associate Professor and Physiotherapist, University of Manitoba

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