Introduction
Osteoarthritis is the most prevalent form of arthritis, affecting over 21 million people in the United States. It typically arises as individuals age or due to excessive use of the knee in sports or occupational activities. This condition leads to the gradual deterioration of the protective cartilage at the ends of the knee bones, resulting in painful friction and restricted movement. Treatment options include medications, physical therapy, and knee injections. In cases where non-surgical methods fail to alleviate pain and restore mobility, surgical intervention may be necessary.
Anatomy
The knee is a highly intricate joint, composed of three main bones: the femur (thighbone) sits atop the tibia (larger leg bone), while the patella (kneecap) moves smoothly within a groove on the femur. The strength and stability of the knee come from major muscle groups in the thigh. The joint is cushioned by smooth articular cartilage, which enables pain-free movement. However, when this cartilage deteriorates, the space between the bones narrows and becomes uneven, leading to discomfort.
Causes
Osteoarthritis of the knee develops when the articular cartilage deteriorates, prompting a reaction in the surrounding bone. This results in thickening of the bones and the formation of bony growths known as osteophytes or spurs. The lubricating synovial fluid within the joint thickens and may become inflamed, potentially leading to a condition known as "water on the knee."
The progression of osteoarthritis over several years can significantly reduce the amount of articular cartilage, leading to painful bone-on-bone contact that impairs mobility and complicates everyday tasks.
Risk factors for developing osteoarthritis include:
- Being overweight or obese, which adds stress to the knee joints
- Genetic predisposition
- Advanced age
- A higher prevalence in women over 50 compared to men
- Previous knee injuries
- Repeated stress on the knee from specific activities
- Engagement in high-impact sports
- Certain medical conditions, such as septic arthritis or metabolic disorders
Symptoms
Individuals with knee osteoarthritis may experience pain, swelling, and difficulty in moving the knee, which can hinder activities like walking, squatting, kneeling, or climbing stairs.
Diagnosis
Healthcare providers diagnose knee osteoarthritis by assessing the knee, considering patient symptoms, and reviewing medical history. X-rays are the primary diagnostic tool used to confirm the presence of osteoarthritis.
Treatment
Treatment for knee osteoarthritis is tailored to the individual, depending on various factors, including overall health and disease progression. Options may include physical therapy, lifestyle modifications, medications, surgery, or a combination thereof.
If weight loss is advisable, it can significantly alleviate pressure on the knees. Physical therapy helps to strengthen the muscles around the joint, while a knee brace can offer additional support. Over-the-counter pain relievers like aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) may be recommended, along with stronger prescription medications if necessary. Joint injections, including corticosteroids or viscosupplementation, are also utilized for pain relief.
Surgery
For individuals whose symptoms persist despite conservative treatments, surgical options may be considered. Procedures such as osteotomy and knee replacement (arthroplasty) are common treatments for knee osteoarthritis. An osteotomy involves reshaping the bone to redistribute body weight away from the affected area, followed by casting, splinting, and physical therapy. Recovery time can vary from 3 to 6 months, or up to a year in some cases.
Total knee replacement surgery removes the damaged knee section and replaces it with artificial implants. This procedure is highly successful in alleviating pain and restoring function. Minimally invasive techniques for knee replacement involve smaller incisions, leading to shorter hospital stays, faster rehabilitation, and quicker recovery compared to traditional methods. Your physician will advise on the most suitable knee joint replacement approach for your condition. Most patients report a significant decrease in knee pain and improved ability to perform daily activities following knee arthroplasty.
