The knee joint works like a hinge, allowing movement, similar to a door. It’s made up of three important bones, and they are protected by cartilage. There’s also extra cartilage called the meniscus to help the knee.
Cartilage keeps the knee bones from hurting each other when they move. If they rub against each other, it can be very painful. Because the knee gets a lot of use and can easily get injured, it’s often affected by arthritis. There are different kinds of arthritis, and the type you have decides how a doctor treats it.
Table of Contents
- What is Knee Arthritis?
- What are the different types of knee arthritis?
- What are the different stages of knee arthritis?
- What Causes knee arthritis?
- Knee Arthritis Symptoms
- Factors That Increase Your Risk of Knee Arthritis
- How is knee arthritis diagnosed?
- Treatments for Knee Arthritis
- How to Keep Your Knees Healthy and Prevent Arthritis
What is Knee Arthritis?
Knee arthritis is when the smooth cushioning layer in your knee joint, called cartilage, becomes inflamed and breaks down. Imagine it as the padding on the ends of your knee bones, allowing your knee to move smoothly. This cartilage covers your thigh bone, shin bone, and kneecap.
As knee arthritis gets worse, the cartilage wears away, narrowing the space between your bones. In severe cases, the bones can rub against each other, causing bone spurs (small bumps on the bone).
With time, this cartilage damage can lead to knee deformities like knock knees or bowlegs.
What are the different types of knee arthritis?
There are different types of knee arthritis, including:
Osteoarthritis: This is the most common type. It happens when the protective cartilage in your knee wears away over time, causing bones to rub against each other. This can lead to pain, stiffness, limited movement, and bone spurs. Osteoarthritis often gets worse as you get older.
Post-traumatic arthritis: This is a kind of osteoarthritis that develops after a knee injury, like those from car accidents or sports. It results in cartilage thinning and similar symptoms to osteoarthritis, but these symptoms might not appear until years after the injury.
Rheumatoid arthritis: This is an autoimmune disease where your body’s immune system mistakenly attacks the synovial membrane in your knee joints. It causes ongoing inflammation, leading to pain, stiffness, swelling, and cartilage damage in the knee. Unlike osteoarthritis, rheumatoid arthritis is not linked to age but is related to an immune system problem.
What are the different stages of knee arthritis?
Knee arthritis, specifically osteoarthritis, has five stages that show how it gets worse over time:
Stage 0 (Normal): Your knees are healthy, and there’s no arthritis.
Stage 1 (Minor): Some initial wear and tear in your knee, but no significant pain.
Stage 2 (Mild): Occasional pain and stiffness, but enough cartilage to protect your bones.
Stage 3 (Moderate): More pain, especially during activities like walking or squatting. Cartilage is wearing down, and bone spurs may form.
Stage 4 (Severe): Most cartilage is gone, leading to extreme pain, stiffness, and limited mobility. Surgery may be needed at this point to fix the severe damage.
What Causes knee arthritis?
Knee arthritis can have different causes:
Osteoarthritis (OA): This happens when the cartilage in the knee wears away over time, usually after the age of 50 due to joint wear and tear.
Gouty arthritis: It can be caused by aging, family history, being male (it’s more common in men), obesity (extra weight can lead to higher uric acid levels), and certain medications. It often starts in the big toe and can involve kidney stones and skin nodules.
Rheumatoid arthritis (RA): The exact cause is unknown, but genetics likely play a role.
Post-traumatic arthritis: This is a type of OA that results from past knee injuries, like sprains or cartilage tears.
Knee Arthritis Symptoms
Knee arthritis can show up in various ways, and it’s vital to recognize these signs early for proper care. Here’s a breakdown of the symptoms:
1. Gradual Onset of Pain
Knee arthritis pain usually starts slowly but can also come suddenly. You may feel discomfort, especially in the morning or after sitting for a while. Pain worsens when you:
- Climb stairs
- Stand up from sitting
- Walk on a flat surface
- Sit for a long time
- Have knee pain affecting your sleep.
2. Swelling or Tenderness
Inflammation can lead to:
- Hard swelling due to bone spurs
- Soft swelling with excess fluid around the joint, more noticeable after inactivity.
3. Joint Swelling in Rheumatoid Arthritis (RA)
In RA, joint swelling is common and may come with other symptoms like fever, fatigue, and feeling unwell. RA affects not only joints but also organs like the eyes, heart, and lungs.
4. Buckling and Locking
As knee damage progresses, it can make the joint unstable, leading to moments where it gives way or locks up. RA can damage tendons, affecting knee stability.
5. Cracking or Popping Sounds
When you move your knee, you may notice a grinding feeling or hear cracking sounds (crepitus). This often happens when cartilage is damaged due to rough surfaces and bone spurs from OA and RA.
6. Reduced Range of Motion
OA and RA can limit your knee’s smooth movement, making everyday activities like walking or standing up harder. In advanced stages, you may need a cane or walker for support.
7. Loss of Joint Space
Internal knee damage may not be visible immediately, but X-rays can reveal cartilage damage effects. Normally, cartilage cushions the joint, and X-rays show changes from cartilage damage.
8. Knee Deformities
Knee appearance can change with arthritis:
- RA flare-ups may cause swelling and redness, leading to permanent shape changes.
- OA may weaken knee muscles, causing it to look misaligned or sunken.
Factors That Increase Your Risk of Knee Arthritis
Here are the factors that make you more likely to get knee arthritis:
Age: As you get older, the chance of having knee joint problems increases because knee arthritis gets worse with age.
Heredity: Genes can play a role, like having joint issues in your family or genetic defects.
Excess Weight: Being overweight or obese puts extra pressure on your knees, making you more prone to knee arthritis.
Injury: A significant knee injury or repeated injuries can lead to knee arthritis later in life.
Overuse: Jobs or sports that involve doing the same knee movements repeatedly can raise the risk of knee arthritis.
Gender: Women after menopause are more likely to get knee arthritis than men.
Autoimmune Triggers: Researchers are still studying what causes autoimmune diseases like rheumatoid arthritis.
Developmental Abnormalities: Conditions like knock knees and bowlegs can stress specific parts of the knee joint, leading to cartilage wear and a higher risk of arthritis.
Other Health Conditions: Conditions like diabetes, high cholesterol, hemochromatosis (high iron levels), and low vitamin D levels increase the chance of knee arthritis.
How is knee arthritis diagnosed?
To diagnose knee arthritis, your doctor follows these steps:
Medical History: They ask about your health and past knee problems.
Physical Exam: They check your knee by looking, touching, and watching you walk.
Look for Signs: They search for arthritis signs or injuries in and around your knee.
Determine Affected Knees: They see if one or both knees are affected.
Lab Tests: Some tests like rheumatoid factor or uric acid tests can confirm specific types of arthritis.
These steps help your doctor diagnose knee arthritis accurately and suggest the right treatment.
Treatments for Knee Arthritis
Knee arthritis treatment depends on the type of arthritis you have. There are different options:
1. Lifestyle Changes
- Manage Your Weight: Keeping a healthy weight eases knee stress.
- Stay Active: Try gentle activities like walking, biking, or water exercises for stronger joints.
- Over-the-Counter Pain Relief: Use ibuprofen or aspirin to ease pain and swelling.
- Prescription Pain Medication: For severe pain, tramadol may be prescribed.
- Corticosteroid Injections: These reduce knee inflammation.
- DMARDs: Mostly for rheumatoid arthritis (RA), not osteoarthritis (OA).
3. Symptom Relief
- Heat and Cold Therapy: Apply hot and cold packs for pain and swelling relief.
- Topical Creams: Capsaicin creams can help with localized pain.
4. Mobility Aids
- Canes or Walkers: These assist balance and movement.
5. Alternative Therapies
- Acupuncture: Some find relief from knee arthritis pain through acupuncture.
- Cognitive Behavioral Therapy: Helps cope with pain and manage the condition.
Active Involvement: Be informed about arthritis, identify what worsens or improves symptoms, and consult your healthcare provider for decisions. Also, consider knee muscle strengthening exercises.
If knee pain affects your life greatly, surgery might be suggested. Options include:
- Partial Surgery: Removes damaged tissue.
- Total Knee Replacement: Replaces the knee joint with an artificial one.
In the end, your specific situation and your doctor’s advice determine the best treatment plan.
How to Keep Your Knees Healthy and Prevent Arthritis
Shed Extra Pounds: Losing weight can significantly reduce the strain on your knee and hip joints, helping to prevent knee arthritis.
Stay Active: Contrary to common belief, staying active is essential for those with osteoarthritis. Avoiding a sedentary lifestyle is crucial because it prevents joint stiffness and muscle weakness, which can worsen the effects of osteoarthritis.
Consider Joint Supplements: There are various dietary supplements available, such as glucosamine sulfate, collagen hydrolysate, Boswellia, ginger, turmeric, and soybean and avocado unsaponifiables (ASU). It’s a good idea to consult your doctor to determine which one might be suitable for you.