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Runner's Knee

Mark decided to try out for the varsity cross country team. Over the summer he bought a pair of running shoes and took up jogging. He started with short distances, but soon started increasing his mileage in an effort to get up to race distance in time for tryouts.

After a few weeks, though, Mark began noticing swelling and pain in his right knee. He went to see a doctor and was told he had runner's knee.

What Is Runner's Knee?

Runner's knee is the term doctors use for a number of specific conditions affecting the knee, such as patellofemoral pain syndrome and , to name just two. It's the most common overuse injury among runners, but it can also strike other athletes who do activities that require a lot of knee bending, such as biking, jumping, or skiing.

Runner's knee happens when the kneecap (patella) tracks incorrectly over a groove in the thighbone (femur) known as the femoral groove when you bend and straighten your knee. In healthy knees, the patella rests in the femoral groove and slides easily up and down when you use your knee. But when the patella is out of place, it can irritate the femoral groove and wear away the cartilage beneath the patella, leading to knee pain.

Symptoms of Runner's Knee

The most common symptom of runner's knee is tenderness or pain behind or on the sides of the patella, usually toward the center or back of the knee where the thighbone and kneecap meet. In addition, the knee might be swollen.

The pain will generally feel worse when bending the knee — when walking, kneeling, squatting, or running, for example. Walking or running downhill or even down a flight of steps also can lead to pain if someone has runner's knee. So can sitting for a long period of time with your knee bent, such as in a movie theater.

In some cases, someone with runner's knee may notice a popping or cracking sensation in the knee, as well as a feeling that the knee may be giving out.

If it goes untreated for a long period of time, runner's knee can damage the cartilage of the knee and hasten the development of arthritis.

How Is Runner's Knee Diagnosed?

If you see a doctor about pain in your knee, he or she will review your medical history and ask you questions about your symptoms and the activities you are involved in. Be sure to tell your doctor if you've increased how much time you spend at a certain activity or how often you do it.

The doctor will probably check the alignment of your kneecap, thigh, and lower leg, as well as look at your range of motion. Your doc will also check your kneecap for signs of tenderness or dislocation. You may be asked to squat, jump, or lie down so your doctor can assess your knee's strength and mobility.

In some cases, your doctor may order imaging tests like an X-ray or MRI to see if there is any damage to the structure of your knee or the tissues connected to it.

What Causes Runner's Knee?

Runner's knee can happen for a variety of reasons, many of them having to do with the muscles and bones of the leg. Some of the more common causes are:

  • Direct trauma to the knee. Falling on your knee or taking a blow to the knee can dislocate the patella or move it out of place, causing it to track incorrectly along the femoral groove.
  • Excessive training or overuse. Repeatedly bending and flexing the knee can irritate the nerves around your kneecap and strain your tendons to the point of discomfort.
  • Misalignment of the patella. If your kneecap is out of alignment, activities like running or biking can wear down the cartilage of the kneecap (chondromalacia of the patella), which can lead to pain and irritation in the underlying bone and joint lining.
  • Tight or weak leg muscles. Tight hamstrings and calf muscles can put excessive pressure on the knee when you run, and weak quadriceps muscles can result in misalignment of the kneecap.
  • Foot problems. Flat feet, also called fallen arches or overpronation, can stretch the muscles and tendons of your leg and lead to pain in the knee.

Preventing Runner's Knee

The good news about runner's knee is that you can take precautions to protect yourself against it. If you're going to be doing an activity that puts a lot of stress on your knees, follow these tips:

  • Warm up and stretch before running or doing any other knee-intensive activity, and be sure to stretch again after you're done. Keeping your leg muscles strong and flexible will allow them to support the knee better and make it less likely to be irritated during exercise.
  • Keep yourself in good shape. The heavier you are, the more weight your knees will have to bear with every step you take. By keeping your weight in check, you can minimize the stress on your knees and decrease the likelihood of pain.
  • Use proper running gear. Buy a good pair of running shoes that fit your feet and offer plenty of support, and replace them with a new pair when they show signs of wear or the soles start to lose their shape. If you have flat feet, consider getting shoe inserts or custom-made orthotics.
  • Try to run on soft, flat surfaces. Concrete and asphalt surfaces create extra stress on your knees. If possible, try to run on grass, dirt, or a synthetic track with a softer surface. Running downhill in a straight line can also cause pain in your knees. Walk down hills or run down them in a zigzag pattern.
  • Increase the intensity of your workouts slowly. Build up to the distance you want to run over a period of time. If you're used to only running a mile or so, don't try to go out and suddenly run 5 miles. Work up to it with a series of intermediate steps.
  • If you've had runner's knee before, wearing a knee brace may help.

How Should I Treat Runner's Knee?

Treatment for runner's knee depends on the specific problem that is causing the pain. Fortunately, runner's knee rarely requires surgery, and most cases heal in time. Regardless of the cause of your particular case of runner's knee, here are some things you should do at the first sign of pain:

  • Stop doing activities that hurt your knee. This means no running, cycling, or skiing until the pain goes away and you can resume your activities without pain.
  • Use the RICE formula as soon as you can:
    • Rest: Try to avoid putting weight on your knee as much as you can.

    • Ice: Use a bag of ice wrapped in a towel or cold compress to help reduce swelling.

    • Compress: Wear an elastic bandage or snug-fitting knee sleeve with the kneecap cut out.

    • Elevate: Lie down and keep your knee raised higher than your heart.

  • Take anti-inflammatory medications. Painkillers such as ibuprofen can help relieve pain and reduce swelling in the knee.
  • Do stretching and strengthening exercises. Once the pain and swelling subside, talk with your doctor about an exercise program to improve your knee's strength and flexibility.
  • Get arch supports for your shoes. If flat feet are the cause of your runner's knee, your doctor may recommend orthotics or special inserts to help alleviate the pain.

On rare occasions, someone might need surgery for runner's knee. If your doctor decides this is your best option, he or she may recommend one of two surgeries:

  1. Arthroscopy allows surgeons to remove fragments of damaged kneecap through a small incision.
  2. Realignment is when the surgeon opens the knee to manually realign the kneecap and reduce pressure on the cartilage and other supporting structures.

Surgery is only used as a last resort, though. Most cases of runner's knee get better through routine care and rest.

Reviewed by: Kathleen B. O'Brien, MD
Date reviewed: June 2013