What Causes Knee Pain—and How To Find Relief

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Medically reviewed by Forest Miller, OTR/L

Knee pain affects people of all ages and can stem from various causes, such as injury, arthritis, or overuse. The pain can significantly impede daily activities, limiting mobility and reducing overall quality of life. Promptly addressing knee pain is crucial not only to stop the hurt, but also to prevent long-term complications.

Sources of Knee Pain

The knee is a complex hinge joint. Knowing the parts of the knee and what the parts do can help you better understand what part of your knee is actually causing you pain.

The knee is supported by ligaments that attach the upper leg bone (femur) to the lower leg bone (tibia). Two of the ligaments are the anterior and posterior cruciate ligaments (ACL and PCL), which criss-cross each other within the joint and stabilize movement.

The kneecap (patella) sits on the front of the knee joint to protect it.

The meniscus is a C-shaped cartilage that cushions and protects joint stability. There are two in each knee.

Synovium is a membrane that surrounds the knee joint and is filled with synovial fluid. This fluid facilitates smooth motion while surrounding muscles provide strength and coordination for proper knee function.

Any of these parts can be the source of your knee pain. That means you can feel pain in different areas of the knee, depending on which part of your knee is affected:

• Anterior knee pain: This dull, aching discomfort is localized at the front and center of the knee. It can often be felt behind, below, or on either side of the kneecap.
• Posterior knee pain: This is pain at the back of the knee. It is less common.
• Pain on the side of the knee: Pain can be felt on the inside or outside areas.
• Diffuse: The pain isn’t concentrated to any one area; it is spread throughout the knee.

Symptoms of Knee Pain

How severe your pain is and what it feels like can vary depending on the underlying cause. Besides pain itself, other symptoms that can accompany knee pain include:

• Swelling or redness around the knee joint
• A grating or grinding feeling
• Weakness or instability in the knee
• Popping or clicking
• Limited ability to flex or extend your knee, known as locking
• Warmth or redness of the knee
• Difficulty bearing weight

Potential Causes of Knee Pain

Knee pain can arise from a multitude of causes, including acute injuries and chronic conditions.

1.Injury

Traumatic incidents like a car or sporting accident can lead to immediate knee injury and pain. Sprains and tears of soft tissues like ligaments and the meniscus are some of the most common acute knee injuries. Other common knee injuries are fractures and dislocation.

Some types of knee injuries are more common among athletes. This includes ACL and PCL injuries. ACL tears happen when you change direction quickly or land a jump incorrectly. PCL tears can happen when your knee is hit from the front while bent.

Where you feel the pain can help identify what type of injury you have. For instance, if you feel pain at the back of your knee right after an injury, it might mean there’s something wrong with the ligaments, meniscus, tendons, or nerves in that area. Keep in mind, though, that more than one part of the knee is often impacted when you have a knee injury.

2.Overuse

Over time, repetitive strain or excessive use of the knee joint can cause pain. Overuse can actually be considered a type of injury. But unlike an acute injury that is sudden and causes immediate pain, overuse is an injury that happens over time and with which pain comes on slowly.

Overuse pain tends to be in the front of the knee or deep in the knee behind the kneecap. The pain can worsen with going down stairs or sitting for a long time.

One common overuse injury is runner’s knee, medically known as chondromalacia, which causes pain at the front of the knee.

3.Bursitis

A bursa is a fluid-filled sac that cushions the knee muscles, tendons, and bones. Your knee has six of these sacs. When these bursa sacs become irritated and inflamed, it is known as bursitis. Bursitis might occur due to injury, overuse, or excessive pressure.

You might feel bursitis pain when you press around or move your knee. You might also feel pain during rest. Pain may also spread to surrounding areas. Besides pain, you could also experience swelling, warmth, and redness of the knee.

4.Tendinitis

Tendinitis is inflammation of tendons, which connect muscles to bone. your knee may develop tendinitis after an injury or from overuse. You might also get tendinitis as you age since the tendon loses elasticity.

One type of tendinitis is patellar tendonitis, or jumper’s knee. This is when the patellar tendon that runs from the quadriceps in your thigh to the shinbone becomes weak. You’d feel the pain during any activity that requires you to quickly straighten your knee, such as jumping.

The tendinitis pain you feel in your knee may come at night or worsen when you move. Your knee might also feel stiff in the morning.

5.Arthritis

Arthritis is a broad term encompassing inflammatory conditions affecting the joints leading to pain, swelling, and reduced joint mobility. Two types that commonly affect the knee are osteoarthritis and rheumatoid arthritis (RA).

Osteoarthritis is caused by a gradual wear and tear of joint cartilage over time that causes pain and reduce movement. It’s the most common type of arthritis and the most common reason for joint pain among people 50 or over. Osteoarthritis pain is typically bad in the morning and improves as you get the joints moving. But the pain can return as your activity increases throughout the day.

Osteoarthritis pain is diffuse, meaning you can feel it throughout different areas of your knee.

RA is an autoimmune disorder that can trigger inflammation at the joints, leading to chronic pain and swelling. It usually affects both sides of the body. Your knees are some the most common joints RA affects.

6.Baker’s Cyst

A Baker’s cyst is a fluid-filled lump that develops at the back of the knee. The lump forms because of a buildup of synovial fluid.

Often there are no symptoms other than the lump itself. If it’s particularly big, the cyst may cause some stiffness or discomfort. The swelling it causes may be painful, too. A Baker’s cyst may also cause pain if it ruptures.

A Baker’s cyst often arises as a result of an underlying condition, such as certain injuries or arthritis.

7.Iliotibial Band Syndrome

Iliotibial band syndrome is a condition that affects runners, cyclists, or other people who do a lot of repetitive knee movements. The iliotibial band runs from your hip to your knee. When it gets irritated from the repeated motions, you can experience pain on the outside of your knee.

8.Infection

An infection in the knee can cause severe pain. Known as septic arthritis, the infection can begin due to a bacterial or fungal infection and cause inflammation of the knee. Besides pain, you may have restricted movement of the joint as well as redness or warmth of the affected area and fever.

Risk Factors for Knee Pain

Several risk factors can contribute to the development of knee pain. These include:

• Age: The risk of knee pain often increases with age due to natural wear and tear on the joints.
• Excess weight: Having obesity puts additional stress on the knee joints, increasing the likelihood of pain and arthritis.
• Sex: Women are generally more prone to knee pain and certain conditions like osteoarthritis.
• Previous injuries: Past injuries, especially to the knee, can elevate the risk of chronic pain or arthritis.
• Lack of physical activity: Inactivity or insufficient exercise can weaken the muscles supporting the knee and contribute to pain.
• Participation in certain sports: Sports with high impact or repetitive knee movements, such as running or soccer, can contribute to knee injuries.
• Genetics: Family history may play a role in knee pain, with a predisposition to certain knee conditions being passed down through generations.
• Occupational factors: Jobs that involve repetitive stress on the knees or require heavy lifting, standing, frequent climbing, and squatting may increase the risk of knee pain.

When To See a Healthcare Provider

It’s crucial to reach out to your healthcare provider if you experience any of the following:

• Inability to bear weight on your knee
• Severe pain, even when not putting weight on your knee
• Difficulty flexing your knee or trouble fully straightening it
• Buckling, clicking, or locking of your knee
• Redness or warmth around the knee, especially when accompanied by a fever
• Significant swelling around the knee
• Deformation or misshaping of your knee
• Pain, swelling, numbness, tingling, or bluish discoloration in the calf below the affected knee
• Persistent pain that continues after three days of trying home remedies

How Is Knee Pain Diagnosed?

During an appointment, a healthcare provider will likely conduct a physical assessment of your knees, hips, legs, and various joints.

Diagnostic tests may include imaging tests like an X-ray or computed tomography (CT) scan. They may order a magnetic resonance imaging (MRI) scan if a ligament or meniscus tear is suspected.

They might also perform a joint fluid culture to examine synovial fluid under a microscope.

Treatments for Knee Pain

How to address knee pain depends on what’s causing the pain. Treatment may include at-home interventions, complementary methods, medical intervention, or a combination. Treatment avenues include the following:

• RICE: This stands for rest, ice, compression, and elevation. RICE is a commonly recommended approach for managing knee pain. It’s particularly effective for acute knee injuries.
• Pain pedication: From over-the-counter options like Tylenol (acetaminophen) and nonsteroidal anti-inflammatory drugs (NSAIDs) to more potent prescribed drugs such as opioids, medications can help manage pain.
• Exercise and physical therapy: Certain exercises can strengthen muscles, restore flexibility, and target muscle groups to help alleviate pain. It’s essential to identify exercises that help without causing further knee damage. A healthcare provider can tell you how long you need the exercise program, possibly four to six weeks. Afterward, the exercises can be continued as maintenance.
• Lifestyle changes: Maintaining an optimal weight and avoiding high-impact activities like running can significantly reduce knee stress.
• Complementary therapies: Massage, relaxation techniques, meditation, acupuncture, and yoga may offer knee pain relief.
• Genicular nerve blocks: When your knee hurts, nerves send pain signals to your brain. A genicular nerve block is an injection of numbing medication that pauses those signals to temporarily stop pain. If it works well, there’s a follow-up procedure called radiofrequency ablation that uses heat to stop those pain signals for a more long-lasting relief without surgery.
• Surgery: Primarily reserved for structural damage, surgery should be considered after exploring other options. Surgery is often a resort when your knee pain has not responded to other methods of pain relief.

How To Prevent Knee Pain

To prevent knee pain and maintain overall joint health, consider the following tips:

• Stay physically active: Regular exercise strengthens the muscles around the knee, providing better support and stability. Focus on low-impact activities like swimming or walking.
• Warm-up before exercise: Always warm-up before engaging in physical activities to prepare your muscles and joints. Gentle stretches and light exercises can help prevent injuries.
• Use proper footwear: Wear supportive and well-fitted shoes, especially when engaging in activities that involve impact on the knees.
• Avoid overtraining: Give your body time to recover between workouts to prevent overuse injuries.
• Listen to your body: Pay attention to any signs of discomfort or pain.

Living With Knee Pain

Living with chronic knee pain can be challenging, but adopting effective coping strategies may improve your quality of life. To help cope, you can:

• Manage stress: Get plenty of sleep, engage in recommended activity, and eat a well-balanced diet.
• Practice mind-body practices: Explore mind-body practices like yoga or tai chi, which can enhance overall well-being and contribute to pain management.
• Use assistive devices: Consider using assistive devices like canes or braces to provide additional support and reduce the strain on the knees during daily activities.

A Quick Review

Knee pain can majorly affect your quality of life. The pain could be at the front, back, or side of your knee or even or all over. Injury, overuse, and arthritis are some of the reasons your knee could be hurting. Knowing what’s causing your knee pain can help you treat the pain and avoid pain in the future.

Read the original article on Health.com.