Girls and Sports. Title IX. You Go Girl! : Female Athlete Hot Topics. Women in Sports

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1 You Go Girl! : Female Athlete Hot Topics Rebecca A. Demorest, MD Associate Director, Pediatric and Young Adult Sports Medicine Children s Hospital & Research Center Oakland rdemorest@mail.cho.org Girls and Sports Review a brief history of women and sports Discuss general neurodevelopment as it pertains to sports participation Discuss the physiological differences between females and males that may affect sports participation Review ACL injuries in the female athlete Review the current literature regarding a possible increased risk of concussion in female athletes Women in Sports Olympics o 1896: women banned o 1900: golf and lawn tennis (1.7%) o 1912: diving and swimming (0.9%) Official women s Olympic events o 2006 Winter Games: US women 42.2% / Paralympics 19.6% WWII o All American Girls Baseball League 1970 s o 1972: Title IX of the Educational Amendment Act Mandated equal facilities for women and men at any federally assisted college o Today 904% increase in collegiate female athletes 456% increase in high school female athletes Title IX

2 Women in Sports Neurodevelopment and Sports 1980 s o 700% increase in female participation in sports o Girls US high school teams increased from 15,000 to 70, s o 50% increase in intercollegiate female athletes o 1998: 1/3 females involved in high school athletics vs. 1/27 in s o : Girls make up 42% of all high school and collegiate athletes Pre-pubertal Children and Sports Girls vs. Boys o Comparable physical condition o Similar height, weight, percent body fat, motor skills, strength, endurance o Similar Hb, thermoregulation o Same or slightly less aerobic and anaerobic capacity o Similar injury risk o Can play together until 10 or 11 years old if of similar physical size Girls may exhibit more joint flexibility Adolescent Females and Sports Increased body fat o Adult women 23-27% vs. Men 13-15% o Elite female sprinters 8-10%, female distance 12-16%, elite male gymnasts 4-8% Physiologic Changes o Smaller heart size, stroke volume, lung volume, aerobic capacity, Hb levels o Smaller body mass, less overall articular surface, narrower shoulders, greater varus at the hips, greater valgus at the knees o Similar thermoregulatory capacity

3 Adolescent Females and Sports Less strength, smaller muscle fiber size Minimal increases in muscle strength after menarche o Boys increase strength through puberty Strength o Upper body 30-50% of similarly trained males o Lower Body 70% of similarly trained males Females more flexible and better at balance tasks Why are females at higher risk for anterior cruciate ligament (ACL) injuries? Anterior Cruciate Ligament Major intrarticular knee ligament Prevents anterior translation of tibia on femur ACL deficient knees have a high risk of developing osteoarthritis at a young age 250,000 ACL tears per year in US Average US cost exceeds $ 2 billion / year Surgical Repair with 6-9 month rehabilitation Females with 2-10x increased risk for ACL injury F:M o 4.5:1 High School o 3.6:1 Collegiate o 3.5:1 Basketball o 2.8:1 Soccer ACL Injuries

4 Renstrom P et al. Br J Sports Med 2008;42: NCAA data: Occurrence of anterior cruciate ligament injuries expressed as the rate per 1000 exposures (games and practices combined, through ). Mechanism of ACL Injuries Noncontact (70%) vs. contact injury o Plant and cut o Landing on a straight leg o One-step deceleration Pop Effusion, limited ROM Lachman s test 2008 by BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine Mechanism of ACL Injuries Noncontact (70%) vs. contact injury o Plant and cut o Landing on a straight leg o One-step deceleration Pop Effusion, limited ROM Lachman s test Risk Factor: Anatomy Increased femoral anteversion Excessive tibial torsion Increased Q angle Excessive subtalar pronation Smaller intracondylar notch Smaller ACL diameter

5 Risk Factor: Anatomy Increased femoral anteversion Excessive tibial torsion Increased Q angle Excessive subtalar pronation Smaller intracondylar notch Smaller ACL diameter Risk Factor: Anatomy Increased femoral anteversion Excessive tibial torsion Increased Q angle Excessive subtalar pronation Smaller intracondylar notch Smaller ACL diameter Risk Factor: Anatomy Increased femoral anteversion Excessive tibial torsion Increased Q angle Excessive subtalar pronation Smaller intracondylar notch Smaller ACL diameter Risk Factor: Hormones No conclusive studies correlating menstrual cycle with ACL injury risk ACL has estrogen, progesterone and relaxin receptor sites Increases in estrogen and relaxin decrease rate of collagen synthesis o? effect on ligaments

6 Risk Factor: Environment Prophylactic and Functional Knee Bracing o Not supported Footwear choice o? increased friction coefficient may enhance performance but increase risk for injury Playing Surface o? Increased risk with higher friction, uneven or dry surfaces Risk Factor: Biomechanical Proprioception Neuromuscular Control Muscular strength Recruitment Patterns o Quadriceps vs. hamstring Landing Positions Increase Risk for ACL injury Anterior pelvic rotation Straight back Momentum forward Hip adduction/ir Less hip and knee flexion Excessive valgus at the knee

7 When landing a jump or cutting, women tend to have: Less knee flexion Greater valgus at knee Greater quadriceps and less hamstring activation Malinzak RACS, Kirkendall DT, Yu B, et al. A comparison of knee joint motion patterns between men and women in selected athletic tasks. Clin Biomech 2001;16: ACL Prevention Programs Skiing, basketball, soccer 60-89% reduction in severe ACL injuries Accelerated round turn Multi-step stop for deceleration Emphasize flexed hip over knee over ankle landings Hamstrings Recruitment Increase hip abductor and gluteus medius strength ACL Prevention Programs PEP program- Santa Monica o Prevent Injury and Enhance Performance o 15 min 2-3x/wk o Cincinnati Sportsmetrics o Are Females at Increased Risk for Concussion?

8 Game concussion rate by gender. Baseline Data and Gender 1209 volunteer NCAA Division I athletes Females o Better baseline verbal memory scores o Endorsed more baseline symptoms (1-2/6) Headache, nausea, fatigue, sleeping more, drowsiness, sensitive to light and noise, sadness, nervousness, more emotional, difficulty concentrating Males o Better baseline visual memory scores? Girls more likely to validate symptoms or is there a difference Dick R W Br J Sports Med 2009;43:i46-i by BMJ Publishing Group Ltd and British Association of Sport and Exercise Medicine Covassin T, et al. Sex differences in baseline neuropsychological function and concussion symptoms of collegiate athletes. Br J Sports Med 2006;40: Baseline Data and Gender High School athletes o Gender differences in baseline scores on processing speed and executive function Barr WB. Neuropsychological testing of high school athletes: preliminary norms and test retest indices. Arch Clin Neuropsych 2003;18: Cognitive Impairment and Gender 2 year collegiate study; 79 concussed athletes (41 men, 38 women) o 52% with previous concussion o Neuropsychological testing: preseason, 2 and 8 days post injury o Females with lower visual memory scores o Males more likely to report vomiting and sadness Covassin T, Swanik CB, Schatz P. Sex differences in neuropsychological function and post-concussion symptoms of concussed collegiate athletes. Neurosurgery 2007;61:

9 Cognitive Impairment and Gender Females may be more frequently cognitively impaired than males following concussions o 155 concussed HS athletes o Females with greater declines in reaction times relative to baseline o Reported more post concussion symptoms o Females cognitively impaired 1.7x more frequently than males following concussion Broskek DK, Kaushik T, Freeman JR, et al. Sex differences in outcome following sports-related concussion. J Neurosurg 2005;102: Females with : Greater likelihood of post concussion syndrome Greater incidence of depression following mtbi Greater number of symptoms or persistent symptoms 1 year after concussion Trends? Possible Reasons for Gender Differences Biomechanical Cultural Hormonal Females with smaller head to ball ratio Females with weaker neck muscles Society more protective of? estrogen playing a female athletes protective role in males with increased mortality in females Do we encourage males to play while injured?? Greater angular? Reporting Bias: acceleration of head and -Encourage males not to neck in females report symptoms -Male reluctance to report -Females more honest about symptoms for fear of long term results R W Dick Is there a gender difference in concussion incidence and outcomes? : i46-i50 Br J Sports Med Conclusions Post pubertal physiologic differences between males and females may affect sports participation. Female athletes are at a higher risk for ACL injuries likely secondary to neuromuscular and proprioceptive differences between males and females in muscle recruitment, landing and cutting mechanics, deceleration and strength. ACL prevention programs may be effective at decreasing the risk of ACL injuries. Females may be at increased risk for sustaining concussions; however further research is necessary in this field.

10 Selected References Patel DR, Pratt HD, Greydanus DE: Pediatric neurodevelopment and sports participation: when are children ready to play sports? Pediatr Clin North Am 2002, 49: Silvers HJ, Mandelbaum BR. Prevention of anterior cruciate ligament injury in the female athlete. Br J Sports Med ;2007 (41): i52-i59. P Renstrom P, Ljungqvist, E Arendt E, et al. Noncontact ACL injuries in female athletes: an International Olympic Committee current concepts statement. Br J Sports Med :