What Is Knee Arthritis and How Can It Be Treated?
Osteoarthritis is the most common joint disease and a leading source of chronic pain and disability in the United States. Knee osteoarthritis comprises over 80% of the disease’s total burden and affects almost 20% of Americans over the age of forty-five.
“One thing I commonly see in the office is patients with knee arthritis,” says Marcus A. Rothermich, M.D., a fellowship-trained orthopaedic sports medicine specialist at South Florida Orthopaedics & Sports Medicine.
What Is Knee Arthritis?
The knee is the largest and most solid joint in the body. It is the connector between the lower end of the femur (thighbone), the upper end of the tibia (shinbone), and the kneecap.
“When patients present to the office with knee arthritis, they often have a wearing down of the cartilage, or the bumper cushion, between the femur and the tibia,” says Dr. Rothermich.
The three main types of knee arthritis include:
- Osteoarthritis – a gradual wearing away of knee cartilage. It is the most prevalent form of knee arthritis that develops primarily in adults over the age of 50.
- Rheumatoid arthritis – a chronic, autoimmune disease that attacks the tissues of the knee joint. The disease works symmetrically, meaning that it will impact both knees.
- Posttraumatic arthritis – arthritis that comes about after a severe injury, fracture, or trauma to the knee.
Signs and Symptoms of Knee Arthritis
A knee joint affected by arthritis may be swollen and painful. According to Dr. Rothermich, the pain can be felt anywhere around the knee and evolves gradually over time.
“In the knee, patients have often presented with years of pain either on the inside or the outside of the knee, or simply global knee pain that has progressed for years,” he says.
Other signs and symptoms of osteoarthritis of the knee may include:
- Inflammation in the joint that interferes with bending and straightening the knee
- Discomfort that worsens in the morning, or after resting
- Flare-ups after robust activity
- Locking of the knee as it moves – loose fragments of cartilage can cause clicking, snapping, or grinding noises
- A general feeling of weakness or collapsing in the knee
- Many patients observe increased discomfort during damp or rainy weather
Causes of Knee Arthritis
Age and wear and tear over time are the two highest causes of knee arthritis. As people age, the ability of the cartilage to heal diminishes.
Other causes of knee arthritis include:
- Weight – increased weight puts additional pressure on the knee joint
- Family genetics – inherited irregularities in the shape and size of the knee bones as well as genetic mutations can increase a person’s chances of developing knee arthritis
- Gender – women over 55, have an increased likelihood of developing the disease than men
- Repetitive stress injuries on the job – individuals whose work requires frequent kneeling, squatting, or heavy lifting are more prone to knee arthritis
- Athletic wear and tear – long-term athletes who play soccer, tennis, or running may experience a higher probability of knee arthritis
- Other illnesses – patients with rheumatoid arthritis and specific metabolic disorders including excess iron and growth hormone
Knee osteoarthritis is often accompanied by other illnesses that diminish one’s quality of life including:
- High blood pressure
Treating Knee Arthritis
Nonsurgical treatment is typically the first line of defense in treating knee arthritis. Your physician may recommend an array of options including:
- Minimizing activities that aggravate the pain (i.e., refraining from climbing stairs)
- Replacing high-impact activities (running or soccer) with low-impact activities (swimming or walking)
- Losing weight to reduce stress on the knee
- Physical therapy to increase strength, range of motion, and flexibility
- Helpful devices such as a cane, shock-absorbing shoes or a knee brace
- Applying heat, ice, or pain-relieving creams
Certain medications can be effective in treating the symptoms associated with knee arthritis including over-the-counter, non-narcotic pain relievers and anti-inflammatories, and corticosteroid injections.
According to Dr. Rothermich, it’s important to explore all non-surgical options before considering surgery. “We like to treat patients non-operatively, if possible, with injections, with physical therapy, and with exercise,” says Dr. Rothermich. “But for many patients (their condition) requires surgery and for some patients, it requires a total knee arthroplasty (replacement).”
Studies confirm that patients spend an average of thirteen years exhausting pain-relieving
drugs before undergoing surgery. In the latter phases of osteoarthritis, total knee arthroplasty is often necessary to deal with the deterioration of the joint and the debilitating symptoms that severely hamper daily function.
What is Total Knee Replacement
“Total knee arthroplasty involves a replacement of both the end of the femur bone or the thigh bone and a replacement of the top part of the tibia or the leg bone,” says Dr. Rothermich (as he demonstrates on an actual knee replacement model). “The procedure also involves placing a plastic spacer between where the cartilage used to be between the femur and the tibia.”
In total knee arthroplasty surgery, a surgeon will remove the damaged cartilage and bone, and insert new state-of-the-art metal or plastic joint components to restore normal functioning of the knee.
From 1999 to 2008, total knee replacement procedures in the U.S. more than doubled for the population at large and tripled for people between the ages of 45 to 64. By 2012, surgery for end-stage knee osteoarthritis was performed on almost 660,000 Americans every year.
Recovery After Surgery
According to Dr. Rothermich, surgery is the first step on the path to full recovery as most patients embark on a physical therapy routine to recover full functioning and range of motion.
“Following total knee replacement, all patients go through physical therapy to regain their strength and conditioning,” says Dr. Rothermich. “But after surgery, most patients find that they have a fairly quick recovery over the course of several months, and quickly get back to the lifestyle activities they enjoy whether it’s taking a walk with their grandchildren, getting back on the golf course, or just walking on the beach.”