Knee pain is very common, especially among people who are active or athletic. That’s no consolation, though, when pain limits your ability to participate in the activities you love. Sometimes it can even affect your ability to complete simple daily tasks at home or at work.
But how can you tell whether you’re experiencing a minor symptom or a bigger problem?
“The knee, although a seemingly simple structure, can actually be a very complex joint that has to hold up to a lot of stress and provide shock absorption for the sports and activities that we do,” says Michael Kolosky, DO, orthopaedic sports surgeon and medical director of the musculoskeletal program at Salem Hospital. “If you have certain types of knee pain, you should give your body time to heal. For other types of knee pain, you should talk to a doctor.”
Dr. Kolosky suggests asking yourself certain questions to determine what’s causing your knee pain. “A lot of people will push through and say, ‘No pain, no gain.’” he says. “But you have to listen to your body because you could be doing more damage by trying to work through it.”
The knee is a joint in the leg that contains four types of structures:
Bones: The thigh bone (femur) and shin bone (tibia) meet at the kneecap (patella).
Cartilage: Cartilage is a substance that helps bones glide against each other when you bend or straighten a joint. It also helps absorb impact when you walk, run and jump.
Ligaments: Ligaments are strong bands of tissue that hold bones together and stabilize joints.
Tendons: Tendons are cord-like bands that connect muscles to bones.
Knee pain can occur when any of those structures are injured, overused or inflamed.
Many things can cause knee pain. The most common culprits in active individuals are:
Arthritis: With osteoarthritis, knee cartilage gradually wears away. This common condition causes chronic inflammation and stiffness in one or more joints. It often starts in our 40s or 50s, but it can happen earlier.
Injury: Any part of the knee can get injured, especially if you’re active. Common examples of knee injuries include sprained or strained ligaments or muscles. You can also tear cartilage.
Overuse: Repeated stress on the joint over time, as happens with frequent running or jumping, can cause pain. A common overuse condition is tendonitis, when tendons swell up and become painful.
To begin to understand the cause of your knee pain, ask yourself: Is the pain sharp, and does it occur when you do certain things? Or is it dull and chronic?
“If you have a sharp pain that is reproducible with a particular movement or activity, that is likely to be an injury. It’s your body saying, ‘Stop doing that. You’re making this worse,’” Dr. Kolosky says. “But a dull, low-grade, aching pain after activity often indicates a more chronic condition such as osteoarthritis or an overuse condition.”
Next ask yourself, where is the pain?
“The location of the pain tells us quite a bit about what part of the anatomy could be potentially injured,” Dr. Kolosky says. For example, if the knee buckles or gives out when you change direction and it’s not stable, that could mean an injury to the anterior cruciate ligament, or ACL, a common issue in athletes.
“But if you have trouble twisting or moving side to side, feel the knee catching, and if the pain is along the joint line, that sounds like a possible injury to the meniscus, a C-shaped piece of cartilage in the knee,” Dr. Kolosky adds.
Another common knee diagnosis is patellofemoral syndrome, sometimes called runner’s knee. “Maybe you’re experiencing pain over the front of the knee. You might also feel some clicking, find that stairs are getting more difficult, or running downhill may be difficult,” Dr. Kolosky says. “This could indicate patellofemoral syndrome, involving tendons and cartilage in the front of the knee.”
Dr. Kolosky says you should consider seeing a doctor if you answer yes to any of the following questions:
Is the knee swollen?
Are you having trouble putting weight on that leg?
Is knee pain accompanied by a clicking or popping sound?
Does the knee “catch” or get stuck in certain positions?
Do you feel like your knee isn’t stable? For example, do you feel knee pain when walking, like your knee might give out on you when you step off a curb or change direction?
“Those sorts of things indicate there might be something more serious happening inside the knee, and you should see an orthopedist,” Dr. Kolosky says. “If those red flags are not there, then it’s okay to try home conservative treatments.”
The first strategy to try at home is the RICE approach:
In addition, you may consider taking over-the-counter nonsteroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen or naproxen, Dr. Kolosky says.
“But if you’ve been doing those things for a few weeks or more and you’re not noticing any improvement, it’s definitely time to be evaluated. Similarly, if you’re finding that it’s difficult to do your daily activities, then don’t wait,” Dr. Kolosky advises. “There are treatments that can help get you back as fast as possible to the activities you enjoy or the job you have—and prevent the risk of any further injury or disability of the knee joint.”
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