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Is it a Torn ACL? Knee Injuries: 101

Dec 01, 2020
Athlete holding their leg in pain

Knee injuries are common in athletics. However, those injuries can vary in severity and have a wide range of symptoms. How do you know when the injury is serious enough that you should take your child to see a specialist? Here are symptoms to watch for, especially injuries to the anterior cruciate ligament (ACL).

The ACL is the main stabilizer in the knee. It connects the bone in the upper leg, the femur, to the larger bone in the lower leg, the tibia. ACL tears generally require surgery to repair the ligament and then physical therapy to help the child regain range of motion and strength in their leg.

If your child has one or more of the symptoms listed below, they should be seen by a specialist to have their injury be properly diagnosed and treated.

Signs and Symptoms of an ACL Tear

  • Hearing a “pop” in the knee when the injury occurs
  • Inability to walk or bear weight on the knee
  • Feeling severe pain and rapid swelling of the joint
  • Inability to move knee in the entire range of motion

Along with ACL injuries, other common injuries to the knee include medial collateral ligament (MCL) sprains, meniscal tears, kneecap (patella) dislocations and patellofemoral pain syndrome (PFPS). Here is what to look for with these other knee injuries.

MCL Sprains

The MCL is a ligament on the inside of the knee that helps protect the knee against inward forces.

  • Hearing a “pop” in the knee when the injury first occurs
  • Pain on the inside of the knee
  • Swelling
  • Pain with walking or running

Meniscal Tears

Each knee has a medial and a lateral meniscus. These thin, c-shaped pieces of cartilage act as a shock absorber. They sit between the femur and tibia.

  • Hearing a “pop” in the knee when the injury first occurs
  • Feeling pain, especially when twisting the knee and walking up stairs
  • Possible swelling
  • Feeling as though the knee is “locked in place” while trying to bend it

Patella Dislocations

The patella is a thick bone that sits in the front of the knee, often called the kneecap. The purpose of the patella is to help protect the inside parts of the knee. The patella is part of a tendon that connects the upper and lower parts of the leg. A strong enough impact to the side of the leg can cause the bone to pop out of its resting spot and become dislocated.

  • Obvious deformity
  • Severe pain
  • Swelling once patella is relocated
  • Unwillingness to put full pressure on knee

Patellofemoral Pain Syndrome

  • Feeling pain at the front of the knee
  • Gradual increase in pain while exercising
  • Not experiencing a specific injury
  • Feeling with prolonged bending of the knee

It’s always possible for your child to injure themselves while participating in sports. Knowing what signs and symptoms to look for with knee injuries can help you make the best choices for care. All knee pain should be taken seriously but some injuries are more damaging to the knee’s structure than others. ACL tears, although devastating, do not have to be the end of your child’s athletic career.

With today’s advances in medicine, ACL tears can be treated, and your child can be back playing the sports they love. Proper diagnosis will give your child the best chance for a successful recovery.

A Parent's Guide to Knee Injuries
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Featured Expert

Allison Rowland
Allison Rowland, AT, ATC
Sports Medicine

Allison Rowland, AT, ATC is a board-certified and Ohio licensed athletic trainer for Nationwide Children’s Sports Medicine. She graduated from Defiance College in 2016 with a Bachelor of Science Degree in Athletic Training.

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Pediatric News You Can Use From America’s Largest Pediatric Hospital and Research Center

700 Children’s® features the most current pediatric health care information and research from our pediatric experts – physicians and specialists who have seen it all. Many of them are parents and bring a special understanding to what our patients and families experience. If you have a child – or care for a child – 700 Children’s was created especially for you.