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Anterior cruciate ligament injury

Anterior cruciate ligament injury

Anterior cruciate ligament injury

An anterior cruciate ligament (ACL) injury is a tear in one of the knee ligaments that joins the upper and lower leg bones and keeps the knee in place. When the knee is forced into an unusual position, the ACL and other ligaments can tear, partially or all the way.  Injuries can range from mild to severe and without treatment, the ACL may not be able to control knee movement and the bones may rub against each other. ACL tears occur when children stop or change direction suddenly, twist their knees or bend their knees sideways.

Signs of an ACL injury:

  • Feeling or hearing a pop in the knee at the time of injury
  • Pain on the outside and back of the knee
  • Knee swelling within the first few hours of the injury – swelling that occurs suddenly is usually a sign of a serious knee injury
  • Limited knee movement
  • The knee feeling unstable or giving out

Diagnosing an ACL injury

The doctor will check all the structures of your injured knee and compare them to your noninjured knee. Most ligament injuries can be diagnosed with a thorough physical exam.

Tests that may help your doctor confirm your diagnosis

X-rays – Although they will not show any injury to your anterior cruciate ligament, X-rays can show whether the injury is associated with a broken bone.

Magnetic resonance imaging (MRI) scan – This study creates better images of soft tissues, like the anterior cruciate ligament; however, an MRI is usually not required to make the diagnosis of a torn ACL.

Evaluation and treatment of an ACL injury

If your child’s injury is mild they may be able to recover with the help of physical therapy alone.

The goal of surgery in young patients is to make their knees stable with the least possible risk of affecting growth. During the operation, orthopaedic surgeons insert a tool called an arthroscope into your child’s knee. After surgery, your child will have regular physical therapy to help strengthen muscles and stabilize the knee.