ACL injuries

An anterior cruciate ligament (ACL) injury in a child or adolescent is one of the most serious sports-related injuries. Because a child’s leg is still growing, injury to the ACL can interrupt growth if it is not treated properly. It’s important that your child be treated by someone with extensive experience in treating ACL tears in young people. Our doctors specialize in state-of-the-art technology and cutting edge treatments for ACL injuries in children and adolescents.

The ACL is one of the four main ligaments in the knee that give the knee and leg flexibility and allow it to move easily. Tears of the ACL are among the most common injuries encountered by athletes and leave the knee less stable. A person with an ACL tear experiences reduced mobility and difficulty rotating the knee. Without proper treatment other parts of the knee can become injured as well, causing further problems.

The majority of people who experience ACL tears tend to be athletes because of the pressure put on the ACL during athletic training, such as fast turns when running, or being tackled from behind in football or hockey. Females are more susceptible to ACL injuries than males. There are many causes of ACL injuries, including:

• Intense impacts or collisions – This happens when a person is impacted from behind, causing the knee to move in an abnormal direction.
• A rapid change in direction – When a person is running and quickly makes a turn, causing the ligaments to be jolted in an abnormal direction.
• Suddenly stopping – This puts an unusual type of strain on the ligament.
• Landing wrong from a jump – This is similar to the experience of suddenly stopping. If a person lands at an awkward angle, it can cause damage to the ligament.

Depending on the severity of the ACL tear, symptoms can vary. Most people report hearing a loud pop when the rip occurs. They also feel the sensation of the knee giving out from underneath them. Other ACL tear symptoms include:

• Swelling in the knee
• Pain on the outside or back of the knee
• Restricted mobility in the knee
• The feeling of instability when standing on the leg in question

ACL tear symptoms may be confused with those of other sports injuries, including tears of the meniscus. Generally, people with an ACL tear are in so much pain they must stop all activity. If this happens, it is important to see a doctor immediately. 

Your doctor will conduct a physical exam, checking your knee for swelling and tenderness. He or she will also manually move your knee around to assess range of motion and overall function of the joint.

Other tests that may be done to properly diagnose an ACL tear include:

• X-rays to rule out a bone fracture
• Magnetic resonance imaging (MRI) to show the extent of an ACL injury and signs of damage to other tissues in the knee
• Ultrasound to check for injuries in the ligaments, tendons and muscles of the knee

There are different levels of severity in ACL tears, and some require surgery to treat. Without proper treatment from a trained doctor, other parts of the knee can become injured as well, causing further problems down the road.

ACL tears can be divided into three gradation levels depending on their severity:

• Grade 1 – This is the mildest form of an ACL tear. A person who has a grade 1 tear is still able to walk and maintain some stability from the knee. While the ligament is stretched, it does not tear enough for severe impediment.
• Grade 2 – This is usually referred to as a partial tear. When a grade 2 ACL tear occurs, the ligament is stretched to a point where it becomes loose, making it more difficult to fully support the knee as it should.
• Grade 3 – This is the most severe form of tear and results in a complete rip in the ligament. When this happens, the knee is unstable. Unfortunately, this is the most common of all ACL tears.