Arthritis in the Knees

Arthritis in the knees typically refers to osteoarthritis, a progressive wearing away of the cartilage that cushions the bones in the knee joint. The condition affects an estimated 14 million adults who experience knee arthritis symptoms such as pain and stiffness.

But osteoarthritis doesn't have to sideline you. "An arthritic knee still loves to move. It's just a matter of finding the right type of lower-impact activity to keep an individual active and functional," says Dr. Sourav Poddar, director of the primary care sports medicine program at the University of Colorado School of Medicine.

Knee Arthritis Causes

Years of walking, running, squatting and standing take a toll on the knees starting by middle age. While wear and tear are significant contributors to osteoarthritis, they're not the only risk factors. Others include:

-- Gender. "Women are more likely than men to develop osteoarthritis in the knee," Poddar says. It's unclear why, but some evidence suggests that low estrogen levels after menopause may play a role.

-- Injury. Knee damage can trigger a process that leads to arthritis years later.

-- Overuse. Bending the knee too often and placing too much stress on the joint may play a role in knee arthritis.

-- Obesity. Extra weight places additional force on your knees.

-- Genetics. If you have family members with knee osteoarthritis, you're at an increased risk for developing the condition.

Poddar says a combination of these factors typically leads to arthritis in the knee.

[See: How to Practice Yoga When You Have Arthritis or Another Chronic Condition.]

Knee Arthritis Symptoms

Osteoarthritic knee problems tend to show up gradually after age 50, according to the American Academy of Orthopaedic Surgeons. As cartilage wears away, you may develop bone growths called bone spurs, ligament damage and a narrowing of the knee joint space. That can result in a number of knee arthritis symptoms such as:

-- Stiffness and difficulty bending the knee.

-- Arthritis pain in the knee.

-- Decreased joint function.

-- Redness.

-- Swelling.

-- A crunching or grinding sound when you flex your knee.

When to See a Doctor

When knee pain interferes with your daily activities, it may be time to talk to your primary care doctor or see a specialist such as an orthopedist or rheumatologist.

To diagnose osteoarthritis, your doctor will likely take a full medical history, conduct a physical exam and order an X-ray of your knee.

But you probably won't hear about surgery -- at least not initially. "The time to talk about a knee replacement is only after you've tried the gamut of treatment and your quality of life is affected by the pain associated with knee arthritis," Poddar says.

[Read: Should I Try Acupuncture for Arthritis?]

Initial Arthritis Knee Treatment

Poddar recommends several pill-free approaches as a first line of defense for arthritis pain in the knee.

One of the most important: exercise. Flexing your knees during exercise helps pump a type of natural lubricant called synovial fluid into the joints. Movement also helps maintain range of motion in the knee. "Choose low-impact activity to reduce the likelihood of overloading the joint and causing the knee to swell up," Poddar advises. Swimming or cycling provides a good aerobic workout without placing pressure on the knee.

Muscle strengthening is key to relief for arthritis pain. Strong muscles act as shock absorbers and help take pressure off the knees. Jamie Lamb, a physical therapist at the Hospital for Special Surgery in New York City, recommends focusing on the quadriceps in the front of the thigh, the hamstrings in the back of the thigh, the gluteal muscles in the buttocks and the core muscles, such as the transverse abdominis and the obliques.

And don't forget to stretch your muscles after a workout. "Stretching is important to maintaining the elasticity of the muscles and promoting normal motion and a normal walking pattern," Lamb says.

Other simple approaches to finding relief for arthritis pain include:

-- Rest. "If you have a lot of errands during the day, make sure you give your knee a rest at night," Lamb suggests.

-- Heat and cold therapy. "Heat the knees in the morning to help loosen up stiffness. When you're done with exercise or feeling inflammation, use ice," Lamb says. Helpful tools include heating pads, warm showers, ice packs or even a bag of frozen peas.

-- Weight loss (if you're overweight). "Each pound you lose will take about 5 pounds of force off the knee," Poddar says. "That can help reduce pain and load on the joint."

Arthritis Knee Treatment

When pill-free strategies aren't providing enough relief for arthritis pain, you still have other options for arthritis knee treatment:

-- Steroid injections. Corticosteroids reduce the inflammation in the knee. Poddar says the effect of an injection lasts only a few weeks, but that should be enough time to relieve pain so you can focus on strengthening and stretching your muscles to restore function.

-- Hyaluronic acid injections. Hyaluronic acid acts as a knee lubricant. However, studies are mixed about their effectiveness. "The injections may or may not make a difference," Poddar says. "I have some patients who do well with them and some who don't respond."

-- Orthobiologic injections. Stem cells (cells with the ability to develop into other types of cells), cells derived from human placentas (after a baby is born) and platelet-rich plasma (platelets from your own blood, which are loaded with growth factors) are among newer arthritis knee treatments. But we don't have enough evidence yet to prove that these kinds of injections help. Many are expensive, experimental and not yet approved by the Food and Drug Administration. That doesn't mean all treatments are being offered illegally, although some are. Some may be provided in an academic research setting, while others, like platelet-rich plasma, may be offered "off label," which means it's approved for other uses. The FDA urges caution if you seek a treatment that is not approved or is offered in another country. "The caution we need as medical professionals is to make sure our approach is grounded in science when we talk to our patients, meaning that injecting stem cells into arthritic joints won't regrow cartilage," Poddar says.

-- Braces. A special type of a brace called an unloader brace helps realign the knee joint to remove or unload pressure on areas where cartilage has worn away.

-- Acupuncture. Some evidence suggests acupuncture helps reduce arthritis pain, but it's not conclusive.

[Read: How to Deal With Arthritis Pain in the Hands.]

What About Medication for Knee Arthritis?

"Gone are the days when we'd say to take ibuprofen three times a day for treatment," Poddar points out. That's because long-term use of ibuprofen and other over-the-counter nonsteroidal anti-inflammatory drugs, or NSAIDs such as naproxen, are associated with ulcers, stomach bleeding, heart attacks, stroke and kidney failure. Some risks, such as heart attacks, are associated with NSAID use even in the short term.

This doesn't mean you can't ever take NSAIDs to relieve inflammation when seeking relief for arthritis knee pain. "It's available if you have a bad day," Poddar says. "But use it occasionally, and don't take it more than three days in a row."

Prescription-strength NSAIDs, prescription topical NSAIDs and over-the-counter acetaminophen are also used to treat knee osteoarthritis. Their use should be supervised by your doctor.

The jury is still out on using supplements to treat arthritis pain in the knee, such as chondroitin and glucosamine. Poddar says they may or may not work and there's no harm in trying them. "Try 1500 milligrams of glucosamine per day for six weeks. If it helps, keep taking it; if it doesn't, don't waste your money on it," he advises.

When Nothing Helps With Knee Arthritis

A partial or total knee replacement is sometimes the answer for people with advanced osteoarthritis. However, Poddar notes that it is invasive and should be used as a last resort.

But in most cases, surgery can give people their mobility back. "It can provide a pathway to restore function," Poddar says.

Another Kind of Knee Arthritis

While osteoarthritis is the most common type of knee arthritis, rheumatoid arthritis can also affect the knees. It too causes pain, stiffness, redness and swelling. However, rheumatoid arthritis usually affects numerous joints at a time, not just the knees. Rheumatoid arthritis is an autoimmune disease that occurs when the body attacks the lining of the joints. Treatment focuses on the use of powerful medications to suppress the immune system.

Heidi Godman reports on health for U.S. News, with a focus on middle and older age. Her work has appeared in dozens of publications, including the Harvard Health Letter (where she serves as executive editor), the Chicago Tribune, Baltimore Sun, Orlando Sentinel and Cleveland Clinic Heart Advisor.

Heidi spent more than 20 years as a TV news anchor and health reporter at ABC affiliate WWSB and more than five years as the host of a daily health talk radio show on WSRQ-FM. Heidi has interviewed surgeons in operating rooms, scientists in laboratories and patients in all phases of treatment. She's earned numerous awards for outstanding health reporting and was the first TV broadcaster in the nation to be named a journalism fellow of the American Academy of Neurology. Heidi graduated from West Virginia University with a degree in journalism.

Connect with Heidi on Linkedin or email her at health@heidigodman.com.