Knee pain can make a workout miserable. Even walking on a sore knee can be uncomfortable, as anyone who’s ever had it knows! Almost 25% of adults suffer from knee pain and the incidence is increasing. Two reasons are the aging of the population and an increase in the number of people who are overweight or obese. The more you weigh, the more force your knees have to contend with.
People can develop knee pain for a variety of reasons, from injuries, arthritis, or overuse injuries and the pain can come from degeneration of the cartilage in the joint or from inflammation of the tendons or ligaments. Not surprisingly, osteoarthritis, a condition marked by degeneration of cartilage in the knee, is more common in people who are obese and losing weight can ease the symptoms. But arthritis isn’t the only cause of knee pain. Another common reason for a sore knee is jumper’s knee.
What is Jumper’s Knee?
Jumper’s knee is another term for patellar tendonitis or tendonosis. As the name suggests, this cause of knee pain is more common in athletes who jump and do repetitive high impact activities. Runners can develop it too. If you do plyometrics or play a sport that requires jumping, like basketball or volleyball, you may have experienced a bout of patellar tendonitis yourself.
Jumper’s knee comes from overuse of the patellar tendon, the tendon that connects the knee cap to the shin. The patellar tendon works with the quadriceps muscles to extend, or straighten, the knee. Ordinarily, that occurs without pain, unless the tendon becomes irritated.
When you overuse your patellar tendon through activities such as jumping, the tendon sustains small tears that, ultimately, lead to the knee discomfort that goes with jumper’s knee. Patellar tendonitis, as it’s sometimes called, is more appropriately called tendinopathy since it mostly involves degeneration of the tendon rather than inflammation. The tendon sustains repeated trauma over time and can’t recover quickly enough.
Are You at Risk of Jumper’s Knee?
As mentioned, high-impact exercise, especially if you’re jumping on a hard surface increases the risk of developing a painful case of jumper’s knee. Obesity is a risk as more weight places more pressure on your knees when you jump. Weak quadriceps muscles are another risk factor as the quads are the primary muscle that supports the knees in the front. Tight leg muscles and anatomical abnormalities, including being knock-kneed, bow-legged, or having a discrepancy in leg length are other possible contributors. Jumping, running or sprinting on hard surfaces, especially if you don’t wear shoes that provide enough cushioning can be a factor.
How Do You Know if You Have Jumper’s Knee?
Patellar tendonitis usually comes on gradually. You might first notice the symptoms after beginning a plyometrics program, especially if you don’t give your muscles and tendons enough recovery time between sessions or you increase the intensity too quickly. The cardinal symptom is a pain in the knee, usually around the bottom of the knee cap. Climbing stairs, kneeling, or doing squats may aggravate the discomfort. The symptoms usually come on gradually but, if you don’t heed their warning, they can worsen over time. In some cases, you might experience slight swelling along the tendon. The symptoms are often intermittent at first and are more pronounced after physical activity.
So, what’s going on at the tissue level with jumper’s knee? As mentioned, the tendon has small tears, often referred to as microtears. These tears are usually associated with degenerative changes that lead to knee pain. Pain in the knees is something you shouldn’t ignore. If you have severe or worsening knee pain or a knee injury, schedule an appointment with a sports medicine physician. Repeated jumping or sudden trauma to the knee during jumping or running can lead to a partial or complete tear of the patellar tendon. They may recommend MRI imaging study to rule this possibility out.
What to Do about Jumper’s Knee
The best treatment for jumper’s knee is to stop jumping and doing high-impact exercise until your knees recover. However, complete rest isn’t advisable either as it can take months for jumper’s knee to heal. Studies show that quadriceps strengthening, particularly eccentric loading of the quads, protects against patellar tendonitis. If your symptoms are mild, focus on quad strengthening and eliminate high-impact exercise until you no longer have the pain. One study found that decline eccentric squats using a 25-degree decline board is more effective than squats on a flat surface for rehabbing jumper’s knee. Shift the focus to the eccentric portion of the movement and slow the tempo down.
Also, work on stretching the muscles that oppose your quads, the hip flexors. Tight hip flexors are the norm these days with so many people working desk jobs. Make sure you’re doing a balanced stretching program that includes stretching of both the hip and knee flexors and extensors. You can also wear a knee brace to stabilize the affected knee when you train. Doing this may help relieve some of the discomforts.
Cryotherapy, applying an ice pack to your knees after a workout, helps reduce some of the pain and inflammation associated with jumper’s knee but it won’t necessarily speed up healing. It provides temporary symptom relief. Most physical therapists recommend applying ice for 15 to 20 minutes several times per day, especially after a training session.
Physical therapists offer more advanced treatments for jumper’s knee. Some of these include corticosteroid injections (shouldn’t be taken lightly as repeated injections can damage the tissues), dry needling, platelet-rich plasma therapy, and extracorporeal shockwave treatment. Hopefully, you won’t need these treatments, but it’s nice to know other treatment options are available.
The Bottom Line
Jumper’s knee is a relatively common cause of knee pain and can be slow to heal. To lower your risk, wear shoes that cushion your feet when you work out, avoid hard surfaces, don’t do high-impact exercise every day, strengthen your quads, watch your body weight, and do what you can do correct any anatomical problems that might place you at risk, such as a leg length discrepancy.
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WebMD.com. “Jumper’s Knee”