The number of girls and women participating in all levels of sports has risen greatly in recent years, and the way they play has changed too. Women’s sports used to be played by a slow defensive style. Today, the sports are played with speed, precision, and power. With these changes have come increased injuries, and female athletes have higher injury rates than men in many sports. Knee injuries have been rising in female sports. Anterior crutiate ligament (ACL) injuries have become the most common injury in the knee to female athletes. Females are four times more susceptible to injury then men.
The ACL is a dynamic structure whose main function is to provide primary restraint to anterior tibial subluxation. It provides secondary restraint limiting internal rotation and restraint with the knee in full extension. Along with the posterior crutiate ligament, it provides the axis for knee rotation and links rotation with flexion and extension.
The ligament is primarily made up of two bands, the anteromedial and posterolateral, and an intermediate band sometimes present. The ACL runs from the posteromedial portion of the lateral femoral condyle in an inferior, anterior, and medial orientation to an area just lateral to the medial tibial eminence. The posterolateral band is tightest when the knee is in extension, and the anteromedial band is tightest with the knee in flexion.
The majority of ACL injuries suffered during athletic participation are of the noncontact variety. Three main noncontact mechanisms have been identified planting and cutting, straight-knee landing and one-step stop landing with the knee hyperextended. Pivoting and sudden deceleration are also common mechanisms of noncontact ACL injury. Basketball, soccer, and volleyball consistently produce some of the highest ACL injury rates across various age groups. Other activities with a high rate of injury are gymnastics, martial arts, and running. In most sports, injuries occur more often in games than in practice. Many injuries have occurred during the first 30 minutes of play. One-reason physicians are seeing more ACL injuries in female patients that more women play sports, and they play more intensely. But as they continued to do more studies, they are finding that women’s higher rate of ACL is probably due to a combination of intrinsic and extrinsic factors more than to sheer increase in the number of athletes and intensity of play.
Intrinsic factors originate in the knee joint and are related to its anatomy. The intercondylar notch configuration has received a great deal of attention as a potential factor in ACL injury. Some studies have shown that athletes with smaller intercondylar notch dimensions are at greater risk for ACL injury. Reports show that notch-width indexes were less in women than in men. Another intrinsic factor is loose jointedness. Some studies have suggested that athletes who are loose jointed are at greater risk of injury than those with normal or tight joints.
Anatomic alignment differences, especially the quadriceps angle (Q-angle), have been studied as the cause of gender discrepancies in injury rate. The Q-angle is the angle formed by the intersection of a line from the anterior superior iliac spine to the center of the patella and a line from the center of the patella to the tibial tuberle. Angles up to 17 degrees are considered normal in females. Differences in pelvic structure and lower extremity alignment between men and women have been blamed for much of the ACL problem. A woman’s pelvis is wider than a man’s, creating sharper angle between the calf and thigh and putting stress on the knee. This increases the tendency of the kneecap to pull out of line and rub, causing pain.
A final intrinsic factor is an area of current study is the effect of hormones on ligamentous relaxation, which allows for pelvic changes that accommodate fetal passage through the birth canal. Studies also show that relaxin has systemic effects on ligamentous tissue and increase the risk of ligamentous injuries in pregnant women. The role of estrogen and estrogen receptors may shed light on ACL injuries in female athletes. ACL injuries occur during the ovulatory phase of the athlete’s menstrual cycle. The ovulatory phase typically occurs during days 10-14 of the cycle and is marked by a significant rise in estrogen levels as well as high levels of a hormone called relaxin. Researchers suspect that estrogen and relaxin have profound effects on women’s neuro-muscular systems and the mechanics of soft tissue such as ligaments and tendons. There is a big question if a hormone supplement would protect women.
Extrinsic factors contributing to ACL injury are those originating outside the knee joint. They include specific movement performed during sporting activity, muscle imbalances, playing surfaces, and the use of braces.
To help explain women’s ACL injury rate is the imbalance between hamstring and quadriceps muscle strength. Men tend to have more developed thigh musculature than women, and stability of the knee is thought to be more muscle-dominant in men and ligament-dominant in women. For female athletes, the quadriceps, an ACL antagonist is the dominant muscle group contributing to knee joint stability, while the hamstring dominates in male athletes. Research indicates that women have decreases hamstring-to-quadriceps strength ratios relative to men.
Studies indicate that women athletes have more knee laxity, lower levels of muscle strength and endurance, and different muscle reaction time than male athletes do. Dynamic stress tests revealed that female athletes rely on more on their quadriceps for knee stabilization during sports, compared to male athletes and nonathletic men and women, who first use the hamstring for stabilization. Female athletes took longer to generate maximum hamstring muscle with less endurance and less stability. The muscles around the knee are critical to keeping it in place. The faster the muscles tighten, the more protective they are. Studies show that women often spend more time doing bench presses and leg extensions, which strengthen the quadriceps, and pay little attention to working the hamstrings. Female athletes tend to work on their quadriceps more because they strengthen quickly. Females think their legs are getting stronger, but they are really not. They need to do activities that increase the quickness of the hamstring response, in addition to exercises that build up the quadriceps.
After the injury occurs some athletes are able to stand up and walk, while others are in such great pain that they cannot move. Swelling often begins in the first few hours after injury. Pain progressively worsens, and muscle spasms may develop. The position of the knee maybe abnormal. There might be gross deformity, pulses, and sensations. A swollen knee is held in a flexed position, and active range of motion may be limited by many factors. All acute knee injuries require x-rays with anteriorposterior, lateral, tunnel, and Hughston views.
The female knee may be more cruciate-dependent than the male knee. Sometimes, nonsurgical treatment of a female athlete with an ACL tear is less likely to succeed, and a trial of conservative treatment should be considered only in an athlete with mild signs and symptoms and a realistic possibility of returning to full activity. Arthroscopic surgical repair of an ACL injury is the best treatment for a female athlete. Surgical reconstruction can usually improve stability and performance enough for the athlete to resume a high level of activity. Still, a fair number of people get along well without ACL’s, including guys on every NFL team and some NBA players.
With advances in surgery, athletes have a better then 90 percent success rate to return to the same level as before the injury. In the past, a torn ACL would often end a career. Studies have shown that people who have torn one ACL is more apt to tearing the other one than the average person is to injure one. Many people use braces on their knee after surgery and healing to help stabilize the knee. Yet, the knee is not a simple hinge. It flexes rolls and rotates. That makes it very difficult to design a brace that can simulate knee motion and protect those ligaments as it goes through that range of motion. Braces are costly; even the cheapest braces are expensive.
After the surgery is completed it can take six months to a year for the knee to completely heal. Depending on the doctor and the effort you put to strengthen yourself determines when you are able to do what you always did before the injury. Constant icing of the knee is required to help the swelling. Physical therapy is required to help get the motion back in the knee.
Tips are given out to help prevent ACL injury that can occur. A good coach is believed to help with proper training to reduce your risk of an injury. It is a good idea to play with people at your level. If you play with klutzes below your level, they may make up for their lack of skills with brute force. If they cannot move as fast as you can’t, you may end up tripping over them. On the other hand if you are the klutz, you may twist your knee to keep up. A good coach would be able to see this problem.
For many women, the default posture, how you stand when you are not thinking about it is with the knee hyperextended or arched slightly backward. If you have a bad habit of standing this way, you more likely to land wrong on jump, too. With your landings on jumps, your knees should be bent, with feet under the hips. Landing on bent knees gives the hamstrings a chance to stabilize the knee.
When having to decelerate and change direction fast, take three small stutter steps instead of one big one. Building your leg muscles, especially your hamstrings can help prevent ACL injury. Be thoroughly warmed up before jumping and pivoting hard. It is a good idea to be actually sweating when you are warming up.
When you are exhausted, you shouldn’t be playing. Never play in pain and if the pain continues to return when you begin to play again after resting. Some shoes are too good for playing. If there is too much traction, your foot won’t give way on fast stops, and the resulting torque on your knee can rip the ligament. Lastly, stick to a sport you love. If you think you are insecure about the sport you are in, and feel that it is too risky, then go into something that makes you feel comfortable.
Females have taken great strides to be able to accomplish as much as males in a male dominant world. Women are more competitive and are able to play at great intensity that was thought impossible several decades ago. It is sad that women have many factors against them, making them more susceptible to injuries. Injuries occur all the time. Although there are many suggestions as to how to prevent ACL injuries, we cannot control everything.