Knee injuries, especially tears of the anterior cruciate ligament, are becoming more common in female athletes. Interest in women’s athletics at the college and professional level has changed the face of sports.
Greater participation has heightened appreciation of health and medical issues specific to the female athlete. Studies comparing male to female susceptibility to injury of the anterior cruciate ligament have shown women to have considerably higher rate of injury.
The National Collegiate Athletic Association (NCAA) has gathered statistics over a three year period in the early 90s showing that women suffered anterior cruciate ligament injuries more often than men, nearly 4 times as often in basketball, 3 times as often in gymnastics, and nearly 2 and a half times as often in soccer. Orthopedic doctors, physical therapists and athletic trainers are concerned and have suggested many reasons so many more women tear their ACL.
The anterior and posterior cruciate ligaments cross each other and are the primary stabilizers of the knee (Fig. A).
Together they maintain the rotary stability of the knee and prevent the lower leg (tibia) from moving either too far forward or backward on the upper portion (femur) of the leg at the knee.
The posterior cruciate ligament (PCL) is the larger of the two ligaments which may be part of the reason why the anterior cruciate ligament (ACL) in general, is torn more often.
Many factors have been discussed as the source of women’s tendency to tear their ACL more often. Some are based on anatomical realities such as a narrower femoral notch, increased Q angle, increased ligamentous laxity, inadequate strength, and impaired neuromuscular coordination.
Extrinsic factors such as techniques and skill of the player, improper shoe wear, and the playing surface may also contribute to injury rates.
A narrower femoral notch (the space at the bottom of the femur through which the ACL runs) in women is being suggested as a culprit in ACL injuries (Fig. A).
The tight fit may cause a “shearing” effect on the ACL by the femur.
The Q angle is a measure of the angle between the quadriceps muscle on the front of the thigh and the patellar tendon at the knee (Fig. B).
This angle is greater in the female due to her wider pelvis. Therefore, a women’s knee is made with a naturally greater angle (Fig. C) between the femur and the tibia predisposing it to greater stress. And further, aggravating the tendency to injure the knee is the more pronated or flattened foot that is created by the increased Q angle.
Strength training for women is critical with an emphasis on being in shape before they play their sport. Women tend to be generally more flexible than men, but a program that consists of strengthening and stretching is essential for all athletes involved in sports.
Non-competitive balance and agility training may enhance proprioceptive function and help to reduce the rate of injury as well.
Boys have historically been trained from an early age to use their body in sports activities. Their training includes footwork drills, eye-hand coordination skills, catching and throwing balls which develop their neuromuscular systems. Girls are not exposed to this early motor learning at a young age, putting them at a distinct disadvantage when they decide to get involved in sports in high school.
Especially if they want to play competitively where there is a higher level of play and greater stress on their body. More and more colleges have developed new teams for women, but this brings players with less experience into athletics. It is essential for girls to receive training early, to play competitively later.
Studies have shown that intensity is a factor in injury of the ACL. Injuries were seven times more likely to occur during games than practices. However, physical contact with other players appears to be unrelated in the occurrence of injury.
The ACL is most often injured with an abrupt change of direction or a jump and usually with an activity they have done many times before. The athlete will describe having “felt a pop”, swelling within a couple of hours and knowing there is something wrong with their knee. If the injury is less severe, the athlete may not know they have been injured. Over time they may describe their knee as being unpredictable, giving way sometimes or a having an unsafe feeling with rotational movements.
Years ago an ACL injury could have been an end to the career of a professional or collegiate player. In recent years, doctors have learned more about surgical techniques, while coaches and physical therapists are learning more about rehabilitation. Furthermore, rehabilitation methods have become more aggressive thus shortening the length of recovery periods.
It’s an exciting time in women’s sports! Participation in physical education for girls is essential for their development. Women should be encouraged to play, but play smart and listen to their bodies.
- A Rigorous Comparison Between the Sexes of Results and Complications After Anterior Cruciate Ligament Reconstruction. Sue Barber-Westin, Frank Noyes, MD, Michelle Andrews, MD. American Journal of Sports Medicine, Vol. 25, No. 4, 1997
- Noncontact ACL Injuries in Females. Mary Lloyd Ireland, MD. Proceedings of AOSSM Annual Meeting, 1996.
- Out of Joint. Jack McCallum. Sports Illustrated Magazine.
- Knee Injury Patterns Among Men and Women in Collegiate Basketball and Soccer. Elizabeth Arendt, MD, and Randall Dick, MS. American Journal of Sports Medicine, Vol. 23, No. 6, 1995.