Knee Osteoarthritis

The knee is the largest and one of the most complex joints in the body. It connects three bones:

• The femur (thighbone)
• The tibia (shinbone)
• The patella (kneecap)

Each bone is covered by a layer of articular cartilage that allows smooth motion. Between the femur and tibia are two C-shaped pieces of cartilage called the menisci, which act as shock absorbers. The knee joint is enclosed by a capsule lined with synovial membrane, which produces fluid to lubricate and nourish the cartilage.

Supporting the joint are strong ligaments and muscles that provide stability and control. When the cartilage begins to wear down, friction increases, leading to inflammation and pain. As the joint loses its natural cushioning, everyday activities like standing, walking, or squatting become more difficult.

Knee osteoarthritis is one of the most common causes of chronic knee pain worldwide. According to the Centers for Disease Control and Prevention (CDC), it affects over 30 million adults in the United States alone.

While the risk of OA increases with age, it can also develop earlier due to factors such as:

• Previous knee injury (meniscus tear, ligament injury, fracture)
• Repetitive stress from work or sports
• Genetic predisposition
• Obesity, which increases pressure on the joint
• Poor limb alignment, such as bow-legged (varus) or knock-kneed (valgus) deformity

Women are slightly more likely to develop knee osteoarthritis than men, particularly after menopause, likely due to hormonal and biomechanical factors.

Diagnosis begins with a detailed discussion of your symptoms and a physical examination. Dr. José Vega, Cleveland’s trusted knee specialist, will assess your pain pattern, stiffness, and limitations in daily activity. During the exam, he will evaluate joint motion, alignment, swelling, and tenderness.

Imaging tests are used to confirm the diagnosis and assess the severity of joint changes:

• X-rays can show loss of joint space, bone spurs, and bone hardening (sclerosis).
• MRI may be used to evaluate the cartilage, meniscus, or surrounding soft tissues.

Knee osteoarthritis is typically classified as mild, moderate, or severe depending on the degree of cartilage loss and the patient’s symptoms.

There is no single cure for osteoarthritis, but many effective treatments can relieve pain, improve mobility, and slow progression. Treatment is tailored to each patient’s age, activity level, and severity of symptoms.

Nonsurgical treatments

• Activity modification: Avoiding repetitive high-impact activities such as running or jumping.
• Weight management: Even modest weight loss can significantly reduce knee stress.
• Physical therapy: Strengthening the quadriceps, hamstrings, and hip muscles improves joint stability and decreases pain.
• Medications: Over-the-counter anti-inflammatory drugs (NSAIDs) or topical creams can reduce pain and swelling.
• Injections: Corticosteroid, hyaluronic acid, or biologic injections (such as platelet-rich plasma, PRP) can provide temporary relief and promote joint health.
• Bracing or orthotics: Knee braces or shoe inserts may improve alignment and reduce joint load.

Surgical treatments

When conservative treatments no longer provide adequate relief, surgical options may be considered. These include:

• Arthroscopic surgery: To remove loose fragments or smooth rough cartilage in select cases.
• Osteotomy: Realignment of the leg to redistribute weight on the knee joint.
• Focal knee replacement: In cases of focal areas of cartilage loss that is not yet widespread enough to justify full knee replacement, small metallic implants can be used to help patients return to high demand activities with improved symptoms
• Partial or total knee replacement (arthroplasty): In advanced arthritis, replacing the damaged surfaces with artificial implants can dramatically reduce pain and restore function.

Recovery after surgery involves structured rehabilitation to restore strength and mobility. Most patients experience excellent long-term outcomes with improved comfort and activity levels.

While aging and genetics cannot be controlled, several lifestyle changes can lower your risk and slow the progression of knee osteoarthritis:

• Maintain a healthy weight: Reduces stress on knee cartilage.
• Stay active: Low-impact exercises like cycling, swimming, or walking promote joint health.
• Strengthen muscles: Strong leg and hip muscles stabilize the knee and reduce joint load.
• Prevent injury: Use proper form during sports and exercise.
• Address early symptoms: Early evaluation and treatment can prevent small cartilage changes from worsening.