Why Do My Knees Hurt?

Written by Michael Dreis, MD | Reviewed by Sophie Vergnaud, MD Updated on May 20, 2022

Key takeaways:

• A common cause of knee pain is overuse. Gentle exercise, stretching, and over-the-counter medications can help relieve this type of pain.
• Some types of knee pain may not be related to overuse, such as gout or bursitis.
• Rarely, knee pain can be a sign of a serious underlying illness.

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There are a lot of causes of knee pain. If you suffered a traumatic injury such as a fall, it might be pretty clear what’s causing your pain. If you haven’t had a specific injury, though, it can be a bit more challenging to figure out what’s causing your pain and how to treat it. Most causes of knee pain aren’t serious, though in some cases knee pain can be a sign of other medical conditions.

Here’s a look at different types of knee pain and how to deal with them.

Strain, wear, and other types of knee pain associated with overuse

Some types of knee pain are caused by long-term wear and tear on the knee. Over time, tiny injuries start to add up until you start having significant knee pain. Here are some examples.

Osteoarthritis

Osteoarthritis is a condition where parts of the knee joint start to break down over time. First, the cartilage in the joint, which provides cushioning, begins to wear out. After this, changes to the bone, ligaments, and tendons occur. 

Overuse of the knee is one factor that leads to arthritis. But other factors such as previous knee injuries or surgeries can also contribute. Symptoms of osteoarthritis are swelling, pain with activity, and joint stiffness that slowly worsen over time.

Patellofemoral pain syndrome

Patellofemoral pain syndrome causes pain in the front part of the knee with activity. It’s caused by overuse and misalignment of the patella (knee cap) and the tract it moves in when you move your knee joint. It’s more common in women and young adults.

Soft tissue overuse injuries

Soft tissue overuse injuries involve parts of the knee that aren’t bone, such as the ligaments, tendons, or bursa. These can become injured over time with overuse or repetitive motions. Symptoms can include pain with movement, pain with weight bearing, or localized swelling.

How to relieve knee pain from overuse

Although the causes might be different, there are some basic steps you can take if you have knee pain from overuse:

• NSAIDs (non-steroidal anti-inflammatory drugs), such as ibuprofen or naproxen, are over-the-counter medications you can take for knee pain. They are very effective for this type of pain. They should only be used for short periods of time, though, because they might slow down the healing of some injuries. Also, you should avoid NSAIDs if you have kidney problems or stomach problems such as ulcers.
• Icing the knee can lower pain and swelling.
• Resting or reducing activity for short periods of time may be helpful. You don’t want to stop exercising completely for long periods of time because this can make things worse.
• If your pain lasts a long time, such as more than 1 week, it’s a good idea to see a healthcare provider to get a better idea of what is going on with your knee. Sometimes, X-rays can help with the diagnosis. Additionally, a referral to physical therapy can be helpful. They can show you which exercises to do and how to do them safely.

Best exercises for knee pain

You can improve your knee pain by exercising and stretching to improve strength and flexibility. In fact, exercise is an important part of treating knee pain. Check out this guide for easy-to-do exercises and stretches that can help with knee pain, such as:

• Straight-leg lifts
• Single-leg dips
• Hamstring curls
• Wall squats
• Step-ups
• Quad and hamstring stretches

How to protect your knees while walking, running, or cycling

It’s a good idea to protect your knees during exercise to prevent pain and injuries in the first place. Here are some general tips:

• Start slow. It takes time for your knees to get strong enough for more intense exercise, so give it some time.
• Warm up with gentle exercises. Do these before more intense or sustained activity.
• Don’t ignore pain. Pain is a sign that you are overdoing it, which can lead to overuse injuries.
• Stretch after your workouts. This can help lower tightness and soreness and help prevent injury.

How underuse and lack of use can cause knee pain

Sometimes, lack of activity can lead to knee pain. If you live a sedentary lifestyle, or if you have a period of decreased activity, several changes can happen that put you at risk for knee pain:

• Decreased flexibility develops over time, which can lead to knee pain. Less flexible muscles and joints are more likely to get injured, which can lead to misalignment of joints.
• Decreased strength can lead to misalignment of joints as well.
• Weight gain, which often happens during less active periods, can put more stress on the knees.

Other causes of knee pain that may not be related to activity

Some other causes of knee pain may not be due to activity. Here are some examples.

Bursitis

A bursa is a small sac of fluid in a joint that helps it move smoothly. Sometimes, these sacs can get inflamed and irritated, causing pain. This is called bursitis. 

Bursitis can happen for a lot of reasons, such as kneeling for too long, overuse of the knee, or for no clear reason. Pain can be in different parts of the knee, because there are a few different bursae in the knee. In rare cases, bursitis can be caused by infections. 

Usually, treatment with rest and NSAIDs such as ibuprofen improves pain.

Gout

Gout is a condition where tiny crystals develop in the knee, causing swelling and pain that can be severe. The crystals are made of a substance called uric acid, which builds up in the joints. 

A gout attack can be treated with medications such as NSAIDs, colchicine (Colcrys), or prednisone (Deltasone, Sterapred), which are all anti-inflammatory medications. If you have multiple gout attacks, medications that lower uric acid in the body such as allopurinol (Zyloprim) can help prevent attacks.

Signs that your knee pain is serious

While most causes of knee pain are not life or limb threatening, knee pain can be a sign of more serious illnesses that need prompt medical attention.

Joint infections

Joint infections are a medical emergency. Infected joints are:

• Extremely painful
• Red
• Swollen
• Warm to the touch

You might also have a fever. If you are concerned about a joint infection, see a healthcare provider right away. If you wait too long, the infection can damage your joint, so immediate treatment is important.

Inflammatory conditions

Knee pain could also be a sign of rheumatoid arthritis or other inflammatory conditions. Usually, more joints are involved than just the knee. Joints can be red, swollen, and painful. If you have pain in multiple joints that isn’t improving with simple measures, it’s a good idea to see a healthcare provider.

The bottom line

Knee pain is common, and it can result from either overuse or decreased activity. You can often improve your knee pain with some simple measures. 

In rare cases, knee pain can be a sign of a more serious medical illness, so seeing a healthcare provider for severe pain or symptoms that aren’t improving can be helpful. Sometimes more advanced treatments like physical therapy or even surgery may be needed if symptoms aren’t improving with simple measures.