Knee Pain: Causes, Symptoms, and Treatment Options

What is knee pain?

Knee pain is one of the most common joint problems, affecting 25% of adults in the U.S.¹ Your knee is a hinge joint that allows your leg to bend, straighten, and bear weight. It’s made up of bones (femur, tibia, patella), cartilage, ligaments, and tendons. When any of these structures are injured or inflamed, pain can occur.¹

Knee pain can range from mild discomfort to severe pain that limits daily activities like walking, climbing stairs, or exercising. It may develop suddenly after an injury (acute) or gradually over time due to wear and tear (chronic).¹

Common Symptoms of Knee Pain

Symptoms vary depending on the cause but often include:²

• Swelling and stiffness
• Redness and warmth around the joint
• Weakness or instability
• Popping or crunching sounds
• Difficulty straightening the knee
• Pain during movement or after prolonged sitting

Causes and Risk Factors for Knee Pain

Knee pain can result from several issues:

• Ligament tears: Injuries to the ACL/PCL (anterior cruciate ligament/posterior cruciate ligament) or MCL/LCL (medial collateral ligament/lateral collateral ligament).¹
• Other injuries: Can include sprains, tendon ruptures, or a dislocated kneecap.^1,2
• Overuse: Activities like running or jumping can lead to patellar tendinitis or “runner’s knee.”²
• Chronic conditions: Can include arthritis (osteoarthritis or rheumatoid arthritis), bursitis, and gout.^1,2

You're more likely to experience knee pain if you're older, obese, have a history of injuries, participate (or used to participate) in high-impact sports, or have poor muscle strength.

How is knee pain diagnosed?

Doctors use a combination of physical exams and imaging tests to diagnose knee pain.¹

Medical history

Your doctor will ask you questions about what your pain feels like, how long it's lasted, and other lifestyle factors.

Physical exam

Your doctor will feel and move your knee to check for swelling, tenderness, and range of motion.

Imaging

X-rays may be done to look for any issues with your bones. MRIs can help diagnose soft tissue injuries. Your doctor may also choose to perform an ultrasound to assess joints in real time.

Lab tests

Blood tests or joint fluid analysis may be done to look for underlying infections or inflammatory conditions.

Treatment Options for Knee Pain

Treating knee pain depends on the cause and severity. Your doctor will choose the right treatment plan for your particular pain or injury. Here are some common ways to treat and manage knee pain:

• Home care: PRICE method (Protection, Rest, Ice, Compression, Elevation).¹
• Medications: NSAIDs (nonsteroidal anti-inflammatory drugs, such as ibuprofen or naproxen) or topical gels.¹
• Physical therapy: May include strengthening exercises for quadriceps and hamstrings.¹
• Braces and supports: Help to stabilize the knee.²
• Injections: Corticosteroids or hyaluronic acid for inflammation.¹
• Surgery: For severe injuries or advanced arthritis; can include knee replacements or repairing damaged ligaments.^1,2

Lifestyle Tips for Managing Knee Pain

Managing knee pain often involves lifestyle changes:¹

• Maintain a healthy weight to reduce stress on knees.
• Choose low-impact exercises like swimming or cycling.
• Practice flexibility and strengthening exercises regularly.

Understanding knee pain and its causes is the first step toward relief. With proper care and lifestyle changes, you can protect your knees and maintain an active, healthy life.