Knee Pain: Causes, Symptoms, and Treatment

Although knee pain is common as you age, it doesn’t have to be inevitable. There are ways to prevent it as you age. And if you already have knee pain, there are ways to manage and treat it.

What Causes Knee Pain?

Though lots of things can cause your knees to hurt, arthritis is often to blame. Osteoarthritis, which is when the protective tissue (also called cartilage) in your knee wears away, is common in older adults.

With every step you take, your knees absorb shock. You can expect your knees to absorb about 1½ times your body weight, which can quickly add up. With regular wear-and-tear damage and the pressure that your knees deal with, the pads of cartilage in your knees (called menisci) can weaken.

After the cartilage is worn away, your bones rub against each other. This can lead to swelling, stiffness, and pain.

Nicholas A. DiNubile, MD, a bestselling author and orthopedic surgeon with the American Academy of Orthopaedic Surgeons, says knee pain isn’t normal, but it’s not unusual as people get older.

“With age, it’s very common,” he says. “It’s hard to find somebody who’s been active as they age, who doesn’t have that little crunch under the kneecap when they bend and straighten their knee or when they go up and down stairs.”

Daniel Valaik, MD, an orthopedic surgeon and assistant professor at Johns Hopkins University, agrees.

“We mostly think of osteoarthritis as a kind of mechanical wearing away of the joint,” he says. “It’s just like treads on a car tire. At 40,000 to 50,000 miles, those treads are just going to wear out. Even if you get great tires, they’re going to wear out.”

You might be more likely to have knee pain if you:

Besides osteoarthritis, there could be other reasons for your knee pain. Your knee could hurt because of:

Ways to Prevent Knee Pain

There are also ways to stop knee pain before it happens. Things like building muscle, skipping out on sugary soda and energy drinks, quitting smoking, and losing weight can all help prevent knee pain. Some suggestions include:

Avoid inflammatory foods. DiNubile says it’s a good idea not to eat inflammatory foods.

“If you’re eating a lot of processed foods, you tend to get more systemic inflammation, and that can affect your joints,” he says. “Nutrition is a factor here.”

That’s one of the reasons that the Mediterranean diet is used to manage arthritis and joint pain, DiNubile says. The Mediterranean diet is an eating plan that focuses on fruits and veggies, whole grains, yogurt, red wine, some fish, and healthy fats, like nuts and olive oil. This diet encourages people to eat anti-inflammatory foods, like fish, berries, and olive oil, and limits inflammatory foods, such as sugar, red meat, and most dairy.

Build up muscle. One of the best ways to help your knees is to strengthen your muscles. This takes some of the pressure off your knees by having the muscles absorb the shock, and it also stabilizes your knee joint.

You should try to strengthen your hamstrings and quadriceps — muscles in your thighs — as well as your core and hip muscles.

Ditch the soda and energy drinks. About 80% of your body’s cartilage is made up of water. If you don’t drink enough water, your body has to use the water in your cartilage and other areas, which can harm joints like your knees.

By trading the soda and energy drinks for water, you can stay hydrated and protect your joints.

Don’t smoke. Smoking tobacco can affect your body in lots of ways. Not only does it boost your chances of conditions like cancer or cardiovascular issues, smoking can affect joints like your knees. Smoking encourages inflammation in your body, so it can be harder to heal if you hurt your knees.

Lose weight. If you’re overweight, losing weight can help take pressure off your knees, too. Every extra pound of weight adds about 4 pounds of pressure. For example, if you gain 10 pounds, you’re adding about 40 pounds of extra pressure to your knees.

“A 10-pound weight loss in people who are really heavy can really slow the progression of arthritis and make them feel better,” DiNubile says.

Valaik agrees and compares the extra weight to carrying a heavy bag.

“It’s like walking around with a 40- to 50-pound backpack all the time, and it’s just going to lead to faster arthritis,” he says. Losing weight or keeping a healthy weight is probably the best thing you can do.

What to Do When You Have Knee Pain

If you already have knee pain, some things can make it worse, including activities like:

• Squatting or standing on a hard surface for a long time
• High-impact activities, such as running or basketball

If you have a job where you squat or stand on a hard surface for a long time, try wearing gel shoe inserts or cushioned shoes.

Staying active is important, DiNubile says. Being active regularly helps keep up your joint function, like range of motion and how strong your knees are. Choosing the right activities for you can help, too. Repetitive squats, step-ups, and lunges can “set off fireworks in somebody with a kneecap issue,” he says.

“If you’re overweight and you want to get in shape, maybe you shouldn’t be running, because that puts a lot of extra pressure on the knees,” he says.

Valaik recommends swimming and bike riding. DiNubile suggests activities like walking, using an elliptical machine, yoga, and stretching exercises. If you have a fitness program you like but it is starting to cause pain, check to see if there are changes you can make to continue, he says.

When to See a Doctor

You should see a doctor whenever you have knee pain that’s constant, nagging, or severe. If there’s swelling and you can’t bend or put weight on your knee, it’s probably time to make an appointment, DiNubile says.

“If you have knee pain — real knee pain that doesn’t go away in a couple of days or a week or two — you should probably see your doctor and figure out if there’s something going on,” Valaik says.

Not all knee pain is the same. That’s why it’s so important to see a doctor to diagnose it, DiNubile says.

“You need to have a specific diagnosis, and then, depending on that diagnosis, you’ll have different treatments,” he says. “The number-one thing is to get it checked by somebody who is knowledgeable with knees. Usually, that’s going to be an orthopedic surgeon or sports medicine specialist.”