Introduction: An Anterior Cruciate Ligament (ACL) Injury will end a season at a minimum and can end a soccer career in some cases. The ACL is deep in the knee and attaches the upper leg bone (Femur) to the primary lower leg bone (Tibia), and runs at an angle from front to back. It prevents the Tibia from moving too far forward with respect to the Femur. There is also a Posterior Cruciate Ligament, but since these are seldom injured, it will not be discussed here.
How it occurs: Injury to this ligament is most commonly a non-contact injury occurring when a player makes a cut, steps on uneven ground, or jumps and lands on one leg with the knee locked straight. It can occur through contact, but is less common in soccer.
Girls are more at risk: Depending on what statistics you read, Girls are far more likely to have these injuries than Boys by a wide margin. Some studies have the ratio 1:4 or more for girls over boys. I coached boys up to U-16 and followed those boys until they finished high school and to my knowledge, none had an ACL injury. I also coached girls up to U-18 and know of at least five of those girls who tore their ACL, four had surgery, one of them twice on the same knee. The age range most common for ACL injuries is around 15 to 25, although they can occur earlier and later.
Contributing factors are many, especially with girls. It has been suggested that any or all of the following can contribute to an ACL injury in girls:
- Muscular imbalances
- Lack of flexibility
- Mechanical issues like being “knock kneed”, having extra wide hips or knee “hyper-extension” (where knees bend backward from a normal straight position).
- Hormonal changes
- Fatigue
- Lack of conditioning
- Lack of good soccer skills
- Poor balance and agility
- A smaller than usually ACL ligament
Prevention: There is much a coach and player can do to help prevent such injuries. Strength training, especially plyometric type drills build the leg muscles up to where they can absorb the forces of ground impact and lessen the forces on the ACL. Flexibility exercises along with good agility and balance training all will help. General fitness conditioning to prevent early fatigue is good too. Players and coaches should be informed about how the ligment works and how to protect it. There are good programs for ACL injury prevention, among them are noted below:
Santa Monica PEP Project website
Repair and Recovery: Most complete tears are surgically repaired by using a tendon or ligament from another part of the body to replace the ligament. These surgeries have progressed signficantly over the years, and are now quite effective and many players return to sport after about one year. Some may return sooner, but full recovery usually takes a little longer. A custom brace is often recommended by some surgeons for the first 1-2 years. Tears that are left to heal take almost as long to recover as those who have surgery. In either case, players must go through weeks and months of rehabilitation exercises and eventual progressive drills before they can effectively play soccer. There is always some risk of re-injury, and this is something that players must weight against the long term use of the leg.
It should be noted that each individual physician has their own protocol for type of surgical repairs they use, schedule of rehabilitation, and projected return to sport. There are great variations depending on physician experience and preference.
It’s an old “cliche” but it certainly applies here. Prevention is much better than any other option. An ACL injury will most certainly end a soccer season, and can end a soccer career as well. While some player come back very well from surgery and eventually re-discover their “game”, many do not.
In all cases, ACL injuries, or any significant knee injuries for that matter, must be assessed and managed by a physician, preferably an orthopedic MD.
