Knee pain can make everyday movements such as walking, climbing stairs, or standing up feel like a challenging task. It may develop suddenly after an injury or gradually due to strain, arthritis, or other underlying conditions. While in some cases, knee pain improves with rest, if someone has persistent pain, swelling, or stiffness, it could be due to an underlying cause that may demand medical intervention. In this blog, we cover 12 most common causes of knee pain, symptoms that may appear along with it, and when it’s advisable to consult a doctor.
Common Causes of Knee Pain
1. Ligament Injuries
The knee has four main ligaments that provide stability, and injuries to these ligaments can cause pain, swelling, and difficulty walking. Ligament tears often happen due to sudden twisting movements, direct blows, or awkward landings, making them common in sports like football, basketball, and skiing.
- Anterior Cruciate Ligament (ACL) Tear: Often caused by sudden stops, direction changes, or high-impact sports. It leads to severe pain, swelling, and knee instability, sometimes accompanied by a popping sound at the time of injury.
- Medial Collateral Ligament (MCL) Tear: Usually results from a direct hit to the outer knee, causing pain and swelling on the inner side. MCL injuries often occur in contact sports or activities that involve side-to-side movement.
- Posterior Cruciate Ligament (PCL) Tear: Typically occurs due to a fall or impact to the front of the knee, leading to stiffness and swelling. PCL injuries are less common but can happen in car accidents when the knee hits the dashboard.
- Lateral Collateral Ligament (LCL) Tear: Less common but can happen due to direct force on the inner knee, causing instability and pain on the outer side. LCL injuries may cause the knee to feel wobbly or give out.
2. Meniscus Tear
The meniscus is a piece of cartilage that cushions the knee joint, acting as a shock absorber. A sudden twist, deep squat, or heavy lifting can cause it to tear, leading to pain, swelling, and difficulty bending or straightening the knee. Some people may experience a sensation of their knee locking or catching, making movement uncomfortable. Meniscus tears are common in athletes and older adults with degenerative knee conditions.
3. Tendonitis
Tendons connect muscles to bones, and excessive strain can lead to inflammation, known as tendonitis. This condition is often seen in people who engage in repetitive knee movements, such as runners, cyclists, and those who frequently jump.
- Patellar Tendonitis (Jumper’s Knee): Common in athletes who do repetitive jumping or running, causing pain below the kneecap. This can make simple activities like climbing stairs or kneeling painful.
- Quadriceps Tendonitis: Affects the tendon above the kneecap, often due to overuse, improper stretching, or muscle imbalances. Pain usually worsens with activity and improves with rest.
4. Bursitis
Bursae are small, fluid-filled sacs that cushion the knee joint and reduce friction between bones, tendons, and muscles. Frequent kneeling, prolonged pressure, or direct trauma can inflame these sacs, leading to bursitis. Pain may worsen with movement, and the knee can become swollen, tender, and warm to the touch. People who work in jobs requiring constant kneeling, such as plumbers and gardeners, are at higher risk.
5. Osteoarthritis
Osteoarthritis is the most common form of arthritis affecting the knee. It occurs when cartilage gradually wears away, leading to pain, stiffness, and reduced mobility. This condition worsens over time, especially in people over 50, those with previous knee injuries, and individuals who carry excess weight. Morning stiffness, joint swelling, and difficulty with everyday movements are common symptoms. Cold weather and increased activity may make the pain worse.
6. Rheumatoid Arthritis
Unlike osteoarthritis, rheumatoid arthritis is an autoimmune disease where the immune system mistakenly attacks the lining of the knee joint. This leads to chronic inflammation, pain, stiffness, and joint deformity over time. Rheumatoid arthritis usually affects both knees and can cause flare-ups of pain and swelling. If left untreated, it can lead to significant joint damage, making movement difficult.
7. Gout and Pseudogout
- Gout: Caused by excess uric acid forming crystals in the knee joint, leading to sudden and severe pain, redness, and swelling. Gout attacks can happen unexpectedly and often worsen at night.
- Pseudogout: Similar to gout but caused by calcium crystal deposits. It leads to episodes of knee pain and stiffness, typically affecting older adults. Unlike gout, pseudogout tends to develop more gradually.
8. Knee Infections (Septic Arthritis)
A bacterial infection in the knee can cause severe pain, swelling, warmth, and difficulty moving the joint. Infections can occur due to open wounds, surgical complications, or bacteria traveling through the bloodstream. Septic arthritis requires immediate medical attention, as untreated infections can lead to permanent joint damage. Fever and chills may also be present, indicating a serious infection.
9. Obesity and Excess Weight
Carrying extra weight puts increased pressure on the knee joints, which can lead to cartilage breakdown and a higher risk of osteoarthritis. Even a small weight reduction can significantly reduce stress on the knees, helping to alleviate pain and slow joint damage. People with obesity may also experience inflammation that contributes to knee discomfort, even without arthritis.
10. Flat Feet and Poor Alignment
Abnormal foot structure, such as flat feet or high arches, can alter knee alignment and lead to strain over time. Poor posture and improper walking mechanics can also contribute to knee pain by placing uneven stress on the joint. People with flat feet often experience discomfort in their knees, hips, and lower back, especially after prolonged standing or walking.
11. Muscle Weakness and Lack of Flexibility
Strong muscles provide support to the knee joint, reducing stress on the bones and ligaments. Weak thigh and calf muscles fail to stabilize the knee, increasing the risk of injuries. Tight muscles can also pull on the knee joint, causing discomfort. Regular stretching and strengthening exercises can help maintain knee stability and prevent pain, especially in physically active individuals.
12. Overuse and Repetitive Strain
Frequent kneeling, prolonged standing, or repetitive motions—such as running or cycling—can cause wear and tear on the knee joint over time. This can lead to chronic pain, inflammation, and conditions like patellofemoral pain syndrome (runner’s knee). Overuse injuries are common in athletes and individuals whose jobs involve repetitive knee movements, making rest and proper conditioning essential for knee health.
Symptoms that May Accompany Knee Pain
Knee pain is often accompanied by other symptoms that can help identify the underlying cause. These include:
- Swelling and Redness: Can indicate inflammation from arthritis, bursitis, or an injury. Sudden swelling may suggest a more serious issue like a ligament tear or infection.
- Stiffness and Limited Movement: Difficulty bending or straightening the knee is common with arthritis, meniscus injuries, and prolonged inactivity.
- Popping or Clicking Sounds: A popping sensation may occur with ligament injuries, while grinding noises could be due to cartilage wear or arthritis.
- Weakness or Instability: A knee that gives out may point to ligament damage, muscle weakness, or nerve issues.
- Locking or Catching Sensation: If the knee gets stuck in a bent position, a meniscus tear or loose cartilage may be the cause.
- Sharp or Dull Pain: Sharp pain is often linked to acute injuries like ligament tears or fractures, while dull, persistent pain may indicate arthritis or overuse injuries.
When Should You See a Doctor for Knee Pain?
It is important to seek medical attention if knee pain is persistent, severe, or accompanied by other concerning symptoms. You should see a doctor if you experience:
- Severe or sudden swelling that occurs without an obvious injury.
- Inability to bear weight or a feeling that the knee might collapse.
- Visible deformity or significant bruising after an injury.
- Persistent pain and stiffness that do not improve with rest or home care.
- Signs of infection, such as fever, warmth, and redness around the knee.
- Gradually worsening pain that interferes with daily activities, which may suggest arthritis or another chronic condition.
- Consult Today
- Knee pain can make even the simplest tasks feel difficult, but the right care can help you find relief and regain mobility. If your symptoms are persistent, worsening, or affecting your daily routine, seeking medical attention is the next step. At Max Hospital, specialists provide thorough evaluations and treatment options suited to your condition, from managing joint inflammation to addressing injuries and long-term concerns. Schedule a consultation at Max Hospital to discuss your knee pain and take a step toward better movement and comfort.
Frequently Asked Questions
How does excess weight affect knee pain and joint health?
Excess weight puts additional strain on the knee joints, increasing the risk of conditions like osteoarthritis. The added pressure accelerates cartilage wear, leading to pain, stiffness, and reduced mobility. Maintaining a healthy weight can help reduce knee stress and slow joint degeneration.
Are certain occupations or sports more likely to cause knee pain over time?
Jobs that involve frequent kneeling, squatting, heavy lifting, or standing for long hours—such as construction work, nursing, and factory work—can increase the risk of knee pain. High-impact sports like running, basketball, football, and skiing also place repeated stress on the knees, making injuries more likely. Proper training techniques and protective gear can help reduce strain.
Can poorly fitted footwear contribute to knee pain?
Yes, wearing unsupportive shoes can affect knee alignment and increase joint strain. High heels, worn-out shoes, and footwear without proper arch support can lead to knee pain by altering how weight is distributed across the legs. Choosing well-cushioned, supportive shoes can help maintain proper knee alignment and reduce discomfort.
Does cold weather make knee pain worse?
Many people with knee pain notice increased stiffness and discomfort in cold weather. This may be due to changes in barometric pressure, which can affect joint tissues, or reduced blood flow to the knees in colder temperatures. Staying warm, moving regularly, and using heat therapy can help ease weather-related knee pain.
Are there any exercises that help strengthen the knee and reduce pain?
Yes, low-impact exercises like swimming, cycling, and walking can help strengthen the muscles around the knee without excessive strain. Specific strengthening exercises, such as straight leg raises, hamstring curls, and gentle squats, can improve stability and support the knee joint. Stretching and flexibility exercises can also help prevent stiffness. Consulting a doctor or physiotherapist before starting a new exercise routine is advisable.
Is it safe to use heat or ice therapy for knee pain, and when should each be used?
Both heat and ice therapy can help, depending on the cause of knee pain. Ice is best for acute injuries, swelling, or inflammation, as it helps reduce pain and numbs the area. Heat therapy is more effective for chronic pain, stiffness, or muscle tension, as it improves blood flow and relaxes the muscles. It’s important to use each therapy for about 15-20 minutes at a time and avoid applying directly to the skin to prevent burns or frostbite.