Anterior Cruciate Ligament Tears  (ACL Tears)

What is an ACL tear?

An ACL tear is an injury to the anterior cruciate ligament (ACL). The tear can be partial or complete. The ACL is one of the four main ligaments in the knee. It runs through the center of the knee and connects the thigh bone (femur) to the shin bone (tibia). It works with the posterior cruciate ligament (PCL) to prevent the shin bone from sliding in front of or behind the thigh bone.

When too much stress is put on the ACL, it can tear. This mostly occurs during athletic activity when abruptly stopping or slowing down, turning rapidly, twisting, landing incorrectly or getting hit in the side of the knee. ACL tears in children and teens are most common in contact sports such as basketball, football and soccer. ACL tears often occur with other injuries to the knee.

What are the signs and symptoms of an ACL tear?

Symptoms of an ACL tear include:

• A popping noise when the injury occurs
• Immediate, severe knee pain
• Swelling around the knee, usually within 24 hours
• Feeling unstable or like the knee is giving out
• Bruising
• Loss of range of motion in the knee

A physical exam is used to diagnose an ACL tear, often in combination with an MRI. Your child may also have an x-ray to check for bone fractures.

What causes an ACL tear?

An ACL tear is caused by stress put on the knee as a result of incorrect movement or accident. This most often occurs during sports when abruptly stopping or slowing down, turning rapidly, twisting, landing incorrectly or getting hit in the side of the knee. ACL tears are more common in contact sports such as football, basketball and soccer. ACL tears are also more common in girls than boys due to skeletal and muscular differences.

How is an ACL tear treated?

Mild ACL injuries may be treated with ice, pain medication and physical therapy. However, in many cases, you child will need surgery to reconstruct the ACL. The surgery usually takes place a few weeks after the injury to allow the swelling to come down. The type of surgery your child needs will depend on their age and developmental stage. Your care team at Arkansas Children’s is experienced in treating all types of ACL injuries in children and teens and will work with you to create the best treatment plan for your child.

• In teens who are done growing, your child’s doctor may recommend standard ACL reconstruction surgery. In this operation, the surgeon uses a piece of tissue (graft) from another part of the body to rebuild the ACL by attaching it to the femur and tibia through drilled holes in the growth plate.
• If your child is still growing, standard ACL reconstruction surgery could damage the growth plates. In these cases, the ACL is reconstructed without drilling through the open growth plates.
• Physical therapy is a crucial part of recovery and usually begins about two weeks after surgery.
• Most children can return to their activities within nine months to a year after surgery. Before returning to their sport, your child's doctor will utilize return to sport testing to better understand  if their knee is healthy and strong enough to return to sport. Your child's doctor may recommend they wear a special knee brace during athletic activities for up to two years after surgery.