Knee Injuries in Kids and Teens

Knee Injuries in Kids and Teens | Causes, Symptoms, and Treatment

Knee injuries in Kids and Teens is a topic that cannot be over-emphasized and we would be addressing the four most common ones, including their Causes, Symptoms, and Treatment. I’m sure you know this, but children are bursting with energy. Unfortunately, accidents happen and, sometimes, they lead to some of the most common knee injuries in kids and teens.

From one adult to another, it’s important to be aware of these injuries, know how they happen and what to do in case your child gets injured. I’ll cover all of that today, so take a sip out of that coffee you’re holding and let’s get to it!

1) Osgood-Schlatter disease

Osgood-Schlatter disease (OSD) is common in kids and teens who enjoy jumping and running sports. It’s mostly seen in both boys and girls aged 8-15.

It is during this time that children experience growth spurts and their growth plates harden from cartilage to bone. The repetitive knee movements involved in running and jumping stress this delicate cartilage. This ultimately leads to inflammation and pain. You might also notice a bump just below your child’s knee.

In some severe cases of Osgood Schlatter disease, a piece of the cartilage (or bone) could also detach.

Recovery time for Osgood-Schlatter disease:

I recommend resting for at least 6 weeks but it won’t fully resolve until after the growth spurt of children and teens.

2) Ligament injuries (sprains)

Our knees have 4 major ligaments,

  • Anterior cruciate ligament (ACL),
  • Posterior cruciate ligament (PCL), 
  • Medial collateral ligament (MCL), and
  • Lateral collateral ligament (LCL)

The ACL and PCL provide our knees with front-to-back stability while the MCL and LCL stabilize our knees from side to side. Of these ligaments, the most commonly injured are the ACL and the MCL.

Kids and teens who play basketball, football, track, and other sports that involve sudden stops and accelerations, lateral movement, and pivoting are at a higher risk of this injury. 

An ACL injury as well as injuries to these other ligaments will come with inflammation, pain, and instability. How severe these symptoms are will also depend on the severity of the sprain. 

Recovery time for knee sprains:

Minor knee sprains can heal after about 6 weeks. More severe cases, particularly those that need surgery, can take up to a year before your children and teens’ medical team clears them to fully return to their sport. 

3) Patellofemoral pain syndrome (PFPS)

PFPS, otherwise known as runner’s knee, is a broad term for pain around the kneecap and anterior knee pain. 

The most common causes of PFPS include overuse, improper alignment of the knee, or weakness in the muscles and ligaments that support the patella. 

Symptoms include pain in front of the knee that gets worse with activity and pain when sitting down for too long. 

Recovery time for runner’s knee:

Symptoms of PFPS take roughly 4-6 weeks to go away when treated conservatively. Rest, knee braces, and physical therapy help make sure that your child’s knee recovers optimally. 

4) Tendonitis

2 types of tendonitis are common in children and teens: 

  • Quadriceps tendonitis, and
  • Patellar tendonitis

The quadriceps tendon connects the thigh bone to the kneecap while the patellar tendon connects the kneecap to the shin bone. Together, they make knee straightening possible while using the patella as a fulcrum. 

In highly active children (especially those who regularly participate in sports), the repetitive knee bending and straightening stresses these tendons. This causes micro tears at a rate that their bodies can’t adequately heal, leading to pain and inflammation. 

Pain from patellar tendon tears is localized under your child’s kneecap whereas the pain from a quadriceps tendon injury is localized above the patella. 

Recovery time for knee tendonitis: 

Luckily, pain from knee tendonitis doesn’t take too long to disappear. Your child should be pain-free in as fast as 3 weeks. However, to be sure, I highly recommend rest and lighter activities for 6 weeks so the tendons can optimally heal. 

How you (parents) can help your child recover from knee injuries:


RICE is an acronym for Rest, Ice, Compression, and Elevation. 

This combination makes recovery more comfortable and timely because it helps regulate inflammation, relieve pain, and optimize blood supply to the injured knee. 

Take note that ice should only be applied for 10-15 minutes at a time. Also, ice should only be used to regulate inflammation which should only take about 2-3 days. Afterward, switch to using heat. 

2) Bracing

There are different braces for different conditions. For instance: 

  • Sprains can benefit from hinged knee braces because they add more stability. 
  • Tendonitis and Osgood Schlatter disease can benefit from knee straps because they relieve pressure directly on the painful tendons and cartilage. 
  • PFPS and any other mild knee injury can benefit from compression sleeves because they minimize pain and inflammation while promoting recovery. 

Disclaimer! Knee bracing does not and should not be used as an alternative to physical therapy, rest, and medication (when necessary). These products are only meant to assist in recovery and/or prevent knee injuries.

3) Physical therapy

Last but not the least, please bring your child to an accredited physical therapy clinic. 

There, they will get a proper physical exam and get their knee injuries diagnosed. Your kids can also get their knee injuries treated by actual health care providers, so they are in capable hands. 


And there you have it: the most common knee injuries in kids and teens, with their causes, symptoms and treatments. 

Just a recap, this includes Osgood-Schlatter’s disease, sprains, tendonitis, and PFPS. In most cases, these knee injuries are caused by overuse. So, make sure to give your child a good balance of rest and exercise.

About the author

Kris Ceniza

I wear many hats for I mainly manage the website’s content but am also one of its editors and writers. I am a physical therapist who focuses on sports injuries but I am also a passionate trainer with a fiery focus on sustainable fitness. To me, that means helping people of all ages – whether that be kids, teens, moms, dads, or even grandparents – achieve their physical and health goals in a way that maintains, if not enhances, their life’s balance. When I see my clients become physically fit and happy without compromising their social life, mental health, and other interests, I know I’ve fulfilled my purpose.

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