At least 200,000 ACL reconstructions are performed each year in the United States. About half of those who suffer a tear of the ACL develop osteoarthritis.
ACL Injury Overview
The knee is a complex, hinge-like joint that connects three bones: your thigh bone (femur), your shin bone (tibia) and the knee cap (patella) at the front to protect the joint. Rope-like ligaments connect the bones to each other. Key among the four ligaments is the anterior cruciate ligament (ACL) in the front of the knee. The ACL may tear when you stop suddenly to change direction or pivot with your foot firmly planted—a common sequence of events in sports such as football, soccer, lacrosse and basketball. A fall while snow skiing may also twist the knee with enough force to tear the ACL. Surgery to repair a torn ACL is likely required to restore full function of the knee.
A physical rehabilitation program is an important part of recovery even when surgery isn’t part of treatment.
- A "popping" sound and sensation
- Severe knee pain
- Swelling that continues hours after the injury
- Feeling the knee is wobbly or unstable
- Limits in range of motion
Athletes, especially women, participating in intense sports such as soccer, football and lacrosse are more likely to tear their anterior cruciate ligaments.
Women are at greater risk for ACL tears than men playing the same sport because of differences in the alignment of the pelvis and leg and differences in muscular strength.
ACL Injury Prevention
- A regular weight training routine can strengthen the muscles around the knee.
- Exercises to increase balance, body awareness, agility and flexibility should also be part of the training routine.
- Women playing high-risk sports should pay special attention to strengthen and stretch their hamstring muscles at the back of the leg as well as their quadriceps at the front of the leg. Jump and landing training is particularly effective for female athletes.
- Pay attention to proper technique when participating in sports.
- Make sure bindings connecting the boot to the ski are properly set when snow skiing.
Tests and screenings for ACL Injury
- MRI (magnetic resonance imaging)
ACL Injury Diagnosis
The first step in diagnosing a torn ACL is establishing a medical history.
Your Wellstar physician will examine the injured knee, comparing it to the uninjured knee. The examination may include a Lachman’s test in which you lie flat on your back with the injured leg bent and your foot flat on the table. The physician moves the lower portion of the leg forward. If it moves too freely, the ACL may be torn. Your Wellstar physician may also check of instability by rotating your foot while bending the injured knee.
The physician may order imaging tests such as x-rays or an MRI to confirm the diagnosis. X-rays do not show ACL tears, but an X-ray may reveal other damage done at the time of the trauma.
ACL Injury Treatment
Treatment of a torn ACL depends on the needs and lifestyle of the patient. A young athlete will need surgery to return safely to the playing field. An older person with a more sedentary lifestyle that doesn’t include intense athletic activities may return to normal activity following a comprehensive physical therapy program.
Surgery may also be an option when your knee is unstable and buckles during daily activities or other parts of your knee, such as the meniscus, were also injured.
An ACL tear can’t be repaired; a new one must be built.
The torn ACL is rebuilt by using a piece of tendon from another part of your leg. This is called an autograft. Another option is to use a tendon from a cadaver that been carefully screened for diseases. This is called an allograft.
Knee arthroscopy is one of the most commonly performed surgical procedures. A miniature camera is inserted through a small incision and miniature surgical instruments are inserted through other small incisions to trim or repair the tear.
Surgery to repair a torn ACL is typically done several days, even weeks, after the injury to allow for swelling to fade and range of motion to return.
Which Approach is Right for You?
We understand the thought of surgery can be overwhelming. That’s why your Wellstar physician will help you decide the course of treatment that’s right for you. The physician will help you weigh the benefits of each treatment approach. You can feel confident your decision will be based on both your input and the expertise and recommendations of your experienced physician.
Ongoing Care for ACL Injuries
Surgery to repair a torn ACL is followed by weeks of physical therapy to restore range of motion and to strengthen the leg muscles. It may be necessary to wear a knee brace for a few weeks. Most people can return to playing sports in six to nine months.
About 90% of patients who have ACL reconstruction surgery report good to excellent results and satisfactory knee stability, according to the American Academy of Orthopedic Surgeons.
Aquatic therapy is an option if you have medication conditions that might limit traditional exercise. Your Wellstar physician may refer you to one of the aquatic therapy programs at one of our physical therapy locations.