Chondromalacia Patellae

(Patellofemoral Syndrome)

Reviewed/Revised Sep 2023
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What is chondromalacia patellae?

Chondromalacia patellae is softening of the cartilage under the kneecap (also called the patella). Cartilage is the smooth, firm tissue that protects bones where they meet, such as the kneecap and other bones in the knee joint.

  • Chondromalacia patellae happens most often in teenagers, especially teen runners and joggers

  • The main symptom is dull, aching pain in the knee

  • It's caused by a kneecap that's a little out of line

  • Doctors treat it with exercises, ice, pain medicine, and sometimes surgery

Inside the Knee (Side View)

What causes chondromalacia patellae?

Chondromalacia patellae is often caused by a kneecap that is out of line so it doesn't slide smoothly over your knee joint. Running or other activities that involve a lot of knee bending make the bottom of the kneecap scrape on the knee bones. This can damage the cartilage on the bottom of the kneecap.

What are the symptoms of chondromalacia patellae?

Chondromalacia patellae causes:

  • Dull, aching pain behind and around the knee

It doesn't cause swelling in the knee.

Pain from chondromalacia patellae often comes when your child:

  • Climbs stairs

  • Plays certain sports

  • Sits for a long time

  • Runs

How can doctors tell if my child has chondromalacia patellae?

Doctors usually tell based on your child's symptoms. X-rays don't help make the diagnosis, but the doctor may do them to look for other problems in the knee.

How do doctors treat chondromalacia patellae?

Doctors treat chondromalacia patellae by having your child:

  • Do exercises to strengthen the quad muscles (those in the thigh) and increase flexibility

  • Ice the knees

Sometimes, doctors do surgery to smooth the underside of the kneecap.

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