It’s involved in climbing, walking on an incline, and several other knee movements.
It’s also the joint affected by a common injury called “runner’s knee.”
The underside of your kneecap sits in a groove within your thigh bone called thepatellofemoral groove.

BruceBlaus / Wikimedia Commons /CC BY 3.0
When you contract thequadriceps musclesof your thigh, they pull on the quadriceps tendon that attaches to your kneecap.
This makes your knee straighten.
In addition, taking part in sports can lead to overuse and damage to the patellofemoral joint.
As the cartilage breaks down, it becomes frayed and can leave the bone exposed.
The surface of bones is rough, and it’s painful when they grind against each other.
In its most chronic form, this condition may require surgical repair.
This is a common injury in runners, soccer players, skiers, and cyclists.
Symptoms of chondromalacia include a dull pain under or around the kneecap.
This may be felt when going up or down stairs or getting out of a chair.
Patellar Dislocation
Knee dislocationshappen when the kneecap slips out of the patellofemoral groove.
This is very painful and can damage the joint cartilage.
Treatment Options
Treatment for an injury to the patellofemoral joint depends on the cause and severity.
The sooner you get a diagnosis and treatment, the sooner you’ll be functional again.
It is where your kneecap connects to the thigh and shin.
Commonly known as runners knee, its irritation and inflammation causes pain at the front of the knee.
In rare or more severe cases, surgery may be required.
If treatment is delayed, it will take longer to heal.
Knee arthritis is typically due toosteoarthritis, a progressive wearing away of the protective cartilage in the patellofemoral joint.
It is treated with physical therapy, exercise, heat or ice therapy, and pain medication.
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