Knee Arthritis

What is knee arthritis?

Knee arthritis is when the hard bone tissue that forms the structure of your knee, and the rubbery cartilage that lines the knee bones, suffers damage and starts wearing away. Normally, the cartilage is smooth, allowing the bones (including the patella or kneecap) to slide past one another with minimal friction as your body moves. This motion is essential for a wide range of activities in daily life. However, when you have knee arthritis, a condition often referred to as knee osteoarthritis, changes occur in the cartilage that makes it rough, and the joint may grind, crack, or pop with movement.

The most common symptoms of knee arthritis include pain, swelling, and stiffness in the knee. It often causes a dull, aching pain that feels worse when you’re active, resulting in difficulty walking. Sometimes, the pain is sharp and it may be difficult to put weight on the leg, with patients reporting their knee giving out without warning or even locking up. This can lead to a level of disability in extreme cases.

As opposed to most health conditions, there is no cure for knee arthritis. However, you can treat joint pain and stiffness with rest, ice, compression, elevation, and OTC pain relievers. Knee replacement surgery may be recommended when the arthritis is severe and all other treatments haven’t worked. This involves creating a new artificial joint with metal and plastic components, replacing the damaged space inside the knee.

What are the symptoms of knee arthritis?

Knee arthritis can cause knee pain, swelling, and stiffness. Symptoms usually start off mild and slowly worsen, but sometimes they happen suddenly. They may come and go, affecting the normal life of patients with periods of time when they may not have any symptoms.

A buildup of fluid inside the knee, referred to as an effusion or “water-on-the-knee,” can result in the knee swelling and limiting its movement. Arthritis can also cause injuries to the muscles around the knee, like the quadriceps (thigh) muscle, leading to weakening.

The muscles at the back of the knee (hamstrings) may tighten and stop the knee from fully straightening. If the arthritis is severe, the knee may become bowed or knock-kneed as the cartilage wears away unevenly.

Main symptoms

• Pain (usually dull and aching but can be sharp and severe)
• Swelling
• Stiffness (hard to fully bend and straighten)
• Cracking, popping, grinding when moving
• Bowing or knock-kneed deformity
• Buckling, "knee giving out", and instability in the knee
• Difficulty walking
• Locking of the knee

What are the causes of knee arthritis?

Knee arthritis may not have a direct cause outside of normal wear and tear. However, certain risk factors increase the chances of developing arthritis, including:

• Genetics (inherited)
• Prior injury or injuries to the knee
• Previous knee surgery
• Wear-and-tear from strenuous activity
• Being overweight
• Autoimmune disorders (rheumatoid arthritis, psoriatic arthritis)

At-home treatment

Knee arthritis symptoms can often be treated at home and improved with lifestyle changes, but it may take 2–6 weeks of regular treatment to notice an improvement.

• Rest
• Ice the knee
• Elevate the knee
• Compress the knee with an ACE wrap or nylon knee sleeve (available at drugstores and online)
• Wear a brace, which has metal hinges on the sides to provide additional support. Braces don’t prevent arthritis from getting worse, but they may make it easier to walk and be active.
• Weight loss - reducing the amount of stress the body puts on the knee joint can improve pain. However, it does not solve the underlying cause.

OTC medications

• Ibuprofen (Advil, Motrin) and naproxen (Aleve) are anti-inflammatory drugs (NSAIDs) that relieve pain and reduce the inflammation from arthritis.
• It’s important to take NSAIDs regularly—not only when the pain is very bad. The biggest mistake many people make is giving up on OTC medication too soon. It can take 1–2 weeks of regular use to notice an improvement. While most people can take OTC medications safely for a few weeks, you should check with your doctor.
• You can also try a topical NSAID, such as diclofenac (Voltaren), which you apply directly to your knee for pain relief.

Herbal supplements

There are many different types of supplements available for arthritis, but there’s limited evidence showing that they work.

The most commonly used supplements for arthritis include glucosamine/chondroitin, turmeric, and MSM (methylsulfonylmethane). Some studies show they may help symptoms, but there isn’t any evidence that they reverse or prevent arthritis from getting worse.

Topical pain relievers that you apply to your skin, such as CBD oil, arnica gel, and Biofreeze, are also available over the counter.

Medical care

Prescription NSAIDs

You may need to take a prescription pain reliever. See a healthcare provider if at-home care doesn’t improve your symptoms or if the pain and swelling are severe. Prescription NSAIDs include:

• Meloxicam (Mobic)
• Celecoxib (Celebrex)
• Diclofenac (Voltaren)
• Nabumetone (Relafen)

Knee X-rays help confirm the diagnosis of arthritis and determine how severe the arthritis is. The radiologist would be looking for characteristic bone spurs visible by x-ray. The more bone spurs exist and the smaller the area between the femur and tibia, the greater the damage and disease progression. You may be referred to an arthritis specialist—usually an orthopedic surgeon—to discuss treatment options or for further imaging (such as an MRI).

If your arthritis is caused by an autoimmune disease like rheumatoid arthritis, you’ll be referred to a rheumatologist, who can prescribe other types of medications.

Injections

Cortisone injections and hyaluronic acid injections (“gel shots”) can help with pain and inflammation that doesn’t improve with medication or for people who can’t take NSAIDs.

Physical therapy and exercise

Your doctor may recommend physical therapy to help reduce stiffness and strengthen the muscles around the knee joint. Therapy includes strength and flexibility exercises and cold and hot therapy. The stronger knee muscles can reduce one's difficulty walking, which in turn helps you exercise more.

And, low-impact exercise can also help reduce symptoms and improve mobility, and such activities are safe for knees.

If you’re overweight, losing weight can be a really good way to relieve pain. Every pound lost takes 3-4 pounds of pressure off of the knee.

Surgery

Surgery for knee osteoarthritis—total knee replacement—may be necessary if your symptoms don’t improve with other types of treatments and you can no longer tolerate your symptoms like difficulty walking, knee giving out, locking, and persistent pain.

The damaged cartilage tissue is removed and replaced with metal and plastic parts. When the knee is replaced, you no longer have arthritis in the joint. Patients generally tolerate the surgery but there can be a need to re-do the knee surgery over time, depending on whether it's a partial or a full replacement, and what kind of materials are used in the knee to keep the ends of the bones gliding past each other smoothly.

Is walking good for arthritis in the knee?

Walking, a low-impact exercise, keeps arthritic joints from becoming too stiff while helping maintain your body's strength and condition. Other low-impact activities, like riding a bike (stationary or road) and swimming, can help you stay active without exerting too much pressure on the knee.

Being active will not necessarily inflict further damage on the joint or accelerate the progress of arthritis. But a good rule of thumb is: If it hurts, don’t do it.

Why does it feel like my knee is locking?

Your knee locking is a symptom of the cartilage in the knee "catching" on itself as your knee is flexing and/or extending. The cartilage tissue changes significantly as a result of osteoarthritis. Sometimes, a flap can actually tear and hang in the knee joint space. When your knee is moving, the damaged cartilage covering one bone can hook onto the cartilage of the other bone, causing momentary resistance and the feeling of locking. This can often also explain the sensation of the knee giving out.

Preventive tips

While knee arthritis is generally not a preventable condition, there are a few strategies you can adopt to help maintain the health of your knee joint.

• Do regular low-impact activity. Varying your activities can help lower the chance that you’ll aggravate the arthritis or cause a flare-up of symptoms.
• Maintain a healthy weight, which can reduce the amount of stress on your knee.
• Avoid high-impact activities such as running and jumping. These put more pressure on the joint and can worsen swelling and inflammation.