What Is Knee Osteoarthritis?

Osteoarthritis (OA) is the most common form of arthritis and is often referred to as “wear-and-tear” arthritis or degenerative joint disease.

In a Healthy Knee

• Smooth cartilage covers the ends of the femur (thigh bone), tibia (shin bone) and underside of the patella (kneecap).
• Synovial fluid lubricates the joint for smooth movement.
• Ligaments and muscles stabilize the joint.

With Knee Osteoarthritis

• Cartilage gradually thins and breaks down
• Joint space narrows
• Bone spurs (osteophytes) may form
• Surrounding soft tissues may weaken
• Inflammation increases
• Movement becomes painful and restricted

The prevalence of osteoarthritis increases with age, especially after age 50, due to progressive joint wear. Because it develops from progressive joint wear, knee osteoarthritis becomes increasingly common as people get older, particularly from middle age onward. Over time, untreated knee arthritis can significantly impact walking, climbing stairs, standing and even sleep.

Types of Knee Arthritis

While osteoarthritis is the most common type, other forms of knee arthritis include:

• Rheumatoid arthritis (autoimmune joint inflammation)
• Post-traumatic arthritis (after injury)
• Gout-related arthritis
• Psoriatic arthritis

Some forms, such as rheumatoid arthritis, may affect multiple joints throughout the body.

Primary Osteoarthritis

Develops gradually over time without a specific injury. Most common in adults over 50.

Secondary Osteoarthritis

Occurs after trauma or injury, such as:

• ACL tears
• Meniscus tears
• Fractures
• Prior knee surgery

Post-Traumatic Arthritis

Arthritis that develops months or years after a knee injury.

What Causes Knee Osteoarthritis?

Several factors increase the risk of developing knee arthritis:

• Age (risk increases after 50)
• Family history or genetic predisposition
• Obesity or weight gain (increases joint stress)
• Previous knee injuries
• Repetitive stress or high-impact occupations
• Alignment issues (bowlegs or knock knees)
• Muscle weakness or imbalance

Because the knee is a major weight-bearing joint, it is especially vulnerable to degenerative changes over time.

Symptoms of Knee Arthritis

Symptoms typically develop gradually and worsen over time.

Common signs include:

• Knee pain during activity
• Stiffness after rest or in the morning
• Swelling
• Grinding or clicking (crepitus)
• Reduced range of motion
• Difficulty climbing stairs
• Knee instability or “giving way”
• Night pain in advanced cases

Pain may be localized to:

• The inside (medial compartment)
• The outside (lateral compartment)
• Behind the kneecap (patellofemoral arthritis)

Persistent symptoms warrant evaluation by a knee specialist.

How Knee Osteoarthritis Is Diagnosed

Accurate diagnosis is essential to developing the right treatment plan.

At OrthoTexas, evaluation includes:

Comprehensive Clinical Examination

• Medical history review
• Physical examination
• Pain localization
• Range-of-motion assessment
• Stability and alignment evaluation

Imaging Studies

• X-rays to evaluate joint space narrowing and bone spurs
• MRI (when needed) to assess cartilage, meniscus or ligament involvement
• Laboratory testing if inflammatory arthritis is suspected

There is no single blood test that diagnoses osteoarthritis.

Non-Surgical Treatment for Knee Arthritis

OrthoTexas prioritizes conservative treatment whenever possible. These approaches aim to reduce pain and improve joint function.

Activity Modification

Reducing high-impact activities while maintaining safe movement.

Physical Therapy

Strengthening the quadriceps and hip muscles through physical therapy improves knee stability and reduces joint stress.

Weight Management

Even modest weight loss significantly decreases pressure on the knee joint.

Medications

• Acetaminophen
• Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or naproxen
• Prescription anti-inflammatory medications

Injection Therapy

Corticosteroid Injections

Reduce inflammation and provide temporary pain relief.

Hyaluronic Acid Injections (Viscosupplementation)

Help lubricate the joint and reduce friction.

Bracing

• Unloader braces shift pressure away from damaged areas
• Support braces improve joint stability

Genicular Nerve Blocks or Ablation

For selected patients with persistent pain who are not ready for joint replacement.

Many patients experience meaningful relief with these treatments and may delay or avoid surgery.

Surgical Treatment Options

If conservative treatment no longer provides relief, surgical intervention may be considered.

Arthroscopy

Used selectively to address mechanical symptoms.

High Tibial Osteotomy

Realigns the knee in patients with arthritis affecting one compartment, often considered for younger patients.

Partial Knee Replacement (Unicompartmental Arthroplasty)

Replaces only the damaged portion of the knee while preserving healthy structures.

Total Knee Replacement (Knee Arthroplasty)

Total knee replacement resurfaces damaged cartilage and bone with metal and medical-grade plastic components.

It is typically recommended when:

• Pain interferes with daily life
• Conservative treatment has failed
• Severe joint damage is present

Most patients experience:

• Significant pain reduction
• Improved mobility
• Enhanced quality of life

Preventing Further Joint Damage

Managing knee osteoarthritis includes protecting the joint from further deterioration.

Strategies include:

• Maintaining a healthy weight
• Participating in low-impact exercise (walking, swimming, cycling)
• Strengthening supporting muscles
• Avoiding repetitive high-impact stress
• Using supportive footwear or braces when appropriate
• Addressing alignment issues

Regular monitoring and early intervention help prevent progression to severe joint damage.

Recovery After Knee Replacement

Recovery includes:

• Early mobilization
• Structured physical therapy
• Strength rebuilding
• Gradual return to activity

Many patients return to light daily activities within a few weeks and continue improving over the following months, with full recovery often taking several months.

Thanks to advances in materials and design, today’s implants are built to last well over a decade, and often much longer, depending on patient factors and activity level.

When to See a Knee Specialist

Schedule an appointment at OrthoTexas if you experience:

• Persistent knee pain lasting more than a few weeks
• Swelling that does not improve
• Stiffness limits daily activities
• Difficulty climbing stairs
• Knee pain that wakes you at night
• Reduced mobility affects the quality of life

Early evaluation provides more treatment options and improves long-term outcomes.

Comprehensive Knee Arthritis Care at OrthoTexas

OrthoTexas provides advanced care for knee osteoarthritis and other forms of knee arthritis, including:

• Advanced diagnostic imaging
• Conservative treatment programs
• Injection therapy
• Partial knee replacement
• Total knee replacement
• Personalized rehabilitation planning

Our fellowship-trained orthopedic specialists are committed to relieving pain, restoring mobility and helping you return to the activities you enjoy.