Definition

Osteoarthritis is a common condition affecting the bones and joints. Specifically, osteoarthritis refers to chronic inflammation of the cartilage, and "genu" is the Latin word for knee. Therefore, knee osteoarthritis can be understood as chronic inflammation of the knee cartilage, leading to friction between the bones of the knee.

The knee is composed of three bones: the femur (thigh bone), the tibia (shin bone), and the patella (kneecap), which is located in front of the knee. The ends of these bones are protected by cartilage, forming the knee joint space.

In knee osteoarthritis, the cartilage layer becomes inflamed and damaged, leading to a narrowing of the knee joint space, which results in friction between the bones. This friction can cause symptoms such as pain, swelling, stiffness, and difficulty moving.

Knee osteoarthritis is a common disease, particularly in older adults, though it can also occur in younger individuals. It is estimated that about 13% of women and 10% of men over the age of 60 experience symptoms of knee osteoarthritis. The prevalence increases to 40% in people over 70 years of age.

Causes

This condition is a degenerative inflammatory disease, meaning it is closely related to aging. knee osteoarthritis can be categorized into two types:

• Primary osteoarthritis: Cartilage inflammation in the knee occurs without a clear cause, and the cartilage typically wears down with age.
• Secondary osteoarthritis: Cartilage inflammation results from medical conditions such as injury, congenital abnormalities, autoimmune diseases, hormonal disorders, or metabolic disturbances.

Risk Factor

Several factors can contribute to cartilage and joint inflammation in the knee, increasing the risk of knee osteoarthritis:

• Age: The ability of cartilage to heal and function properly declines with age.
• Weight: Extra body weight adds stress to all joints, including the knees, increasing the risk of knee osteoarthritis in individuals with obesity.
• Genetics: Some individuals are genetically predisposed to develop knee osteoarthritis earlier.
• Gender: knee osteoarthritis is more commonly found in women than in men.
• Injury history: Repeated injuries or activities that put stress on the knees, such as heavy lifting, kneeling, or squatting, can lead to repetitive injury and increase the risk of knee osteoarthritis.
• Occupation: Jobs like soccer, tennis, or running athletes are at higher risk of injuries that can contribute to knee osteoarthritis.
• Other medical conditions: Certain conditions, such as rheumatoid arthritis, can increase the risk of osteoarthritis.

Symptoms

Osteoarthritis is a progressive disease, meaning symptoms worsen over time and can lead to disability. The rate of disease progression varies among patients. Common symptoms include:

• Knee pain that worsens with activity
• Pain that occurs upon waking, during activity, or after sitting for prolonged periods
• Swelling and stiffness in the knee
• A grinding or popping sound when moving the knee joint
• During active inflammation, the knee may feel warm, and the skin may appear red

Diagnosis

Medical Interview

During a consultation, the doctor will ask about:

• Symptoms and how long they have been present
• The specific location of the pain and how long it has lasted
• Factors that worsen or relieve the pain
• The severity of the symptoms
• The patient's activity level and whether they can still perform daily tasks
• Previous medical history
• Medications are being taken
• Family medical history

Physical Examination

Based on the patient's complaints, the doctor will examine the knee and surrounding areas. They will look for any changes in the knee's shape or color and compare the affected knee with the healthy one. The patient's gait and knee joint range of motion will also be assessed. The doctor will move the knee to check for reduced movement, stiffness, and sounds coming from the bones.

Diagnostic Tests

The doctor may also perform additional tests, such as:

• X-ray: This can reveal damage to the bones and cartilage in the knee and show the degree of joint space narrowing.
• MRI: Provides more specific results and is used when the doctor suspects damage to muscles or structures other than the bones.
• Blood tests: These may be done if the doctor suspects other underlying conditions causing knee osteoarthritis.

Management

The main goals of osteoarthritis treatment are to reduce pain and restore knee function. The treatment approach typically combines several therapies, depending on the severity of the condition.

• Weight Loss

For patients with a BMI over 25, weight loss is essential. Patients need to control their diet and engage in low-impact aerobic exercises.

• Exercise

Strengthening the muscles around the knee helps stabilize the joint and reduce pain. Recommended exercises include swimming and walking.

• Medications
  

Pain relievers such as ibuprofen and paracetamol can help reduce pain. However, patients should consult their doctor if the pain persists despite taking these medications. Injections of corticosteroids into the joint can also be an option, especially for reducing localized inflammation in the knee.

• Knee Brace
  

A brace can help redistribute weight away from the side of the knee affected by osteoarthritis. It can also serve as overall knee support.

• Surgery
  

When other treatments fail to provide relief, surgery may be considered, particularly for chronic and severe knee osteoarthritis. There are several surgical options, but they should be discussed in detail with the doctor, as certain conditions may contraindicate surgery.

Complications

Although complications from knee osteoarthritis are rare, untreated cases can lead to:

• Osteonecrosis (bone cell death)
• Chondrolysis (destruction of cartilage cells in the knee)
• Stress fractures are caused by excessive pressure
• Prolonged use of pain medications can lead to stomach and kidney diseases

Prevention

Since osteoarthritis is closely associated with aging, there is no way to prevent getting older. However, the following measures can help reduce the risk of developing knee osteoarthritis:

• Maintain a healthy weight to avoid obesity
• Get enough rest
• Engage in a variety of exercises, combining low- and moderate-intensity activities
• Include strength training exercises in your routine

When to See a Doctor?

Consult a doctor if you experience persistent knee pain that interferes with your daily activities. You can visit a general practitioner first to determine whether your pain is due to knee osteoarthritis.

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