Knee pain is one of the most frequent complaints affecting people of all ages. Whether from sports, aging, or a sudden injury, knee pain can range from mild discomfort to a debilitating condition that affects day-to-day life. Understanding the causes of knee pain can help you better manage your symptoms and take steps toward relief. In this article, we’ll cover the basics of what knee pain is, highlight 10 common knee pain causes, go over treatment options, and discuss when it might be time to see an orthopedic physician.
What Is Knee Pain?
Knee pain refers to any discomfort or ache in the knee joint. This pain can be acute if related to a specific incident or chronic if it lasts for months at a time. Knee pain can also vary in intensity. The knee is a complex joint that supports much of the body’s weight, which is why it’s prone to injury and wear. Because so many structures make up the knee — bones, ligaments, cartilage, and tendons — knee pain can be challenging to diagnose and manage without understanding the underlying cause.
Common symptoms of knee pain include:
- Swelling or stiffness
- Weakness or instability
- Popping or crunching noises
- Difficulty straightening the knee
- Redness and warmth to the touch
While some knee pain symptoms may be related to minor issues that can improve in a short period of time, there are definitely knee pain signs that require treatment and should not be ignored. Each of these symptoms can be linked to specific knee pain causes, which we’ll break down below.
10 Common Causes of Knee Pain
Knee pain can arise from a variety of underlying issues, each affecting the knee joint in unique ways. From common conditions like arthritis to injuries from overuse, here are 10 of the most frequent knee pain causes and how they impact daily movement.
1. Arthritis
Arthritis is one of the primary knee pain causes, affecting millions of people worldwide. The most common types impacting the knee are osteoarthritis and rheumatoid arthritis, which cause joint pain and stiffness as the cartilage deteriorates over time.
- Why It Causes Knee Pain: In arthritis, the cartilage that cushions the knee joints wears down, leading to pain, swelling, and limited range of motion.
2. Tendinitis
Tendinitis is a frequent issue for athletes and people with active lifestyles, particularly those who perform repetitive movements. It involves inflammation of the tendons around the knee, leading to sharp pain and tenderness, especially with movement.
- Why It Causes Knee Pain: Overuse of the knee, especially from repetitive jumping or running, causes the tendons to become irritated, leading to sharp pain during movement.
3. Meniscus Tears
A meniscus tear often occurs from a sudden twist or turn, especially when the foot is planted. This injury affects the rubbery cartilage in the knee, leading to swelling, stiffness, and difficulty moving the joint.
- Why It Causes Knee Pain: This tear can cause the knee to catch, lock, or become stiff, causing pain, especially when twisting or rotating the knee.
4. Ligament Injuries
Ligament injuries, such as a torn ACL (anterior cruciate ligament), are typical in sports that involve rapid changes in direction. These injuries compromise the knee’s stability and can lead to significant pain, swelling, and movement limitations.
- Why It Causes Knee Pain: A torn ligament affects knee stability, resulting in pain, swelling, and difficulty moving or putting weight on the knee.
5. Bursitis
Bursitis is inflammation of the small fluid-filled sacs (bursae) that cushion the knee joint, commonly occurring from prolonged kneeling. This condition results in pain and swelling, especially around the kneecap.
- Why It Causes Knee Pain: When bursae are inflamed, they cause swelling and pain, especially with activities that involve kneeling.
6. Patellar Tendonitis (Jumper’s Knee)
Patellar tendonitis, also known as jumper’s knee, impacts the patellar tendon that connects the kneecap to the shinbone. This condition is particularly common in athletes and causes pain below the kneecap.
- Why It Causes Knee Pain: Overuse from jumping or running can lead to irritation in the patellar tendon, causing pain below the kneecap.
7. Osgood-Schlatter Disease
Osgood-Schlatter disease is common in adolescents undergoing growth spurts and is caused by inflammation where the patellar tendon attaches to the shinbone. This condition results in pain and swelling just below the kneecap, often triggered by physical activity.
- Why It Causes Knee Pain: It leads to swelling, pain, and tenderness below the kneecap, often triggered by physical activity.
8. Gout
Gout is a form of arthritis caused by a buildup of uric acid in the bloodstream, leading to painful crystal deposits in joints, including the knee. It typically causes sudden, intense knee pain, swelling, and redness.
- Why It Causes Knee Pain: These crystal deposits accumulate in the knee joint, causing intense pain, redness, and swelling, often with sudden onset.
9. Dislocation
A dislocated kneecap occurs when the kneecap slips out of its usual position, typically due to a sudden blow or twist. This injury is very painful, causing immediate swelling and a visible change in knee shape.
- Why It Causes Knee Pain: A dislocated kneecap is extremely painful and causes visible swelling and instability, making it hard to move the knee.
10. Iliotibial Band Syndrome (ITBS)
Iliotibial band syndrome, or ITBS, affects the iliotibial band, a ligament that runs along the outside of the thigh to the knee. Common among runners and cyclists, this is one of the most common knee pain causes and results in sharp pain on the outer knee.
- Why It Causes Knee Pain: This repetitive friction causes inflammation on the outer side of the knee, leading to sharp, persistent pain that worsens with activity.
Treatments for Knee Pain
The right treatment for knee pain depends on its cause, severity, and how it affects your daily activities. Here are some common approaches:
- Rest and Ice: Resting and applying ice can reduce inflammation, especially for knee pain from acute injuries or overuse.
- Physical Therapy: Physical therapy can strengthen the muscles around the knee, which reduces stress on the joint. Targeted exercises can improve flexibility, mobility, and support.
- Medications: Over-the-counter pain relievers like ibuprofen or acetaminophen can help manage pain and inflammation. In more severe cases, a physician may prescribe anti-inflammatory medications.
- Knee Braces or Supports: Knee braces help stabilize the joint, particularly for conditions like ligament injuries or arthritis.
- Injections: Corticosteroid pain management injections may reduce pain and inflammation, particularly for arthritis-related knee pain.
- Surgical Intervention: In cases of severe damage, such as a torn ligament or meniscus tear, knee surgery may be necessary. Arthroscopy or knee replacement are common procedures for chronic knee pain causes that don’t respond to other treatments.
When to See an Orthopedic Physician
While mild knee pain can often be treated at home, certain symptoms indicate it’s time to see an orthopedic physician for many knee pain causes:
- Persistent Pain: If knee pain persists despite rest and treatment, a specialist should assess it.
- Severe Swelling: Swelling that doesn’t reduce with ice or worsens could indicate a serious injury.
- Instability: If the knee feels like it might give way or buckle, you could have a ligament injury or structural issue.
- Limited Range of Motion: Difficulty bending or straightening the knee may be caused by a meniscus tear or arthritis.
- Pain with Fever: Fever and knee pain can be a sign of infection and require immediate medical attention.
Overcoming Knee Pain and Living Your Best Life
With so many potential knee pain causes, understanding the source of your discomfort is key to effective treatment and management. From arthritis and tendinitis to ligament injuries and more, each cause requires a unique approach to relieve symptoms and prevent further issues. If you’re experiencing knee pain that affects your quality of life, it’s essential to seek guidance from an experienced orthopedic physician. Taking proactive steps toward diagnosis and treatment can help you return to daily activities without knee pain slowing you down.
At the Orthopedic Clinic, we believe that orthopedics is about treating individual patients, not just the condition. We’ll work closely with you to take your lifestyle and health goals into account before recommending a specific course of therapy. If you’re exploring all of your treatment options for knee pain, our highly skilled physicians and surgeons are here to help you live an active life. Contact us today to learn more.