Overview
Patellar tendinitis is an injury to the tendon that joins the kneecap, also called the patella, to the shinbone. The patellar tendon works with the muscles at the front of the thigh to straighten the knee.
Patellar tendinitis also is called jumper's knee. It's most common in athletes whose sports involve a lot of jumping. Examples are basketball and volleyball. But people who don't play jumping sports also can get patellar tendinitis.
For most people, treatment of patellar tendinitis begins with physical therapy to strengthen the muscles that straighten the knee called the quadriceps muscles.
Symptoms
Pain is the first symptom of patellar tendinitis. The pain most often is between the kneecap and where the tendon joins the shinbone, also called the tibia.
At first, you may feel pain in your knee with jumping, as you start an activity or just after a hard workout. Over time, the pain can worsen. It can get in the way of playing your sport. In time, the pain affects daily movements such as climbing stairs or rising from a chair.
Patellar tendinitis
Patellar tendinitis causes pain in the patellar tendon. The tendon runs from the kneecap, also called the patella, to the shinbone, also called the tibia.
When to see a doctor
For knee pain, try self-care measures first. These include icing the area and reducing or not doing the activities that cause your symptoms for a time.
Call your doctor if your pain:
- Continues or gets worse.
- Keeps you from doing your daily activities.
- Is linked to swelling or redness about the knee joint.
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Causes
Patellar tendinitis is a common injury caused by too much use. The repeated stress on the patellar tendon results in tiny tears in the tendon.
Repeated stress on the tendon without enough time to recover can lead to a weakened tendon. The body tries to heal the damage, which thickens the tendon.
Risk factors
A mix of factors may be part of getting patellar tendinitis. They include:
- Male sex. People assigned male at birth are more likely to get patellar tendinitis.
- Physical activity. Running and jumping most often are linked with patellar tendinitis. Training more than 20 hours a week for this type of impact exercises is a risk factor. Sudden increases in how hard or how often you do the activity also add stress to the tendon.
- Tight thigh muscles. Tight front-of-the-thigh muscles, called quadriceps, and tight back-of-the-thigh muscles, called hamstrings, can increase strain on your patellar tendon.
- Muscular that aren't balanced. If some muscles in your legs are much stronger than others, the imbalance could put strain on your patellar tendon. This uneven pull could cause tendinitis.
- Chronic illness. Some illnesses disrupt blood flow to the knee, which weakens the tendon. Examples include kidney failure, autoimmune diseases such as lupus or rheumatoid arthritis, and diseases such as diabetes that affect how the body uses food to make energy, called metabolic.
Complications
Working through the pain can cause more and larger tears in the patellar tendon. Rarely, the tendon can rupture.
Patellar tendinitis can keep athletes from returning to their sports.
Prevention
To reduce your risk of developing patellar tendinitis, take these steps:
- Don't play through pain. As soon as you feel knee pain while exercising, rest and ice the area. Until your knee is pain-free, don't do activities that put stress on your patellar tendon.
- Strengthen your muscles. Strong front-of-the-thigh muscles can better handle the stresses that can cause patellar tendinitis. A type of exercise called eccentric involves lowering muscles slowly as you return to your start position. An example for the quadriceps muscles is slowly lowering a straight leg to a bent knee position while seated.
- Improve your form. Be sure to use the right form when doing an exercise or sport. You might take lessons or get help from a professional when you start a new sport or use exercise equipment.
