Tricompartmental Osteoarthritis of the Knee: Causes, Symptoms and Treatment Options

Tricompartmental osteoarthritis is a type of knee osteoarthritis that affects all three compartments of the joint: the medial femorotibial (inside), lateral femorotibial (outside), and patellofemoral (under the kneecap).

When the protective cartilage in each of these areas wears down, bones rub together, causing pain, swelling, stiffness and instability. Because the knee is the largest weight-bearing joint in your body, tricompartmental osteoarthritis can have a profound impact on daily activities like walking, standing, and climbing stairs.

Knee Anatomy and the Three Compartments

The knee joint is formed where the femur (thigh bone) meets the tibia (shin bone) and patella (kneecap). Three compartments allow smooth movement:

1. Medial compartment: Inner side of the knee where the femur meets the tibia.
   
2. Lateral compartment: Outer side of the knee where the femur meets the tibia.
   
3. Patellofemoral compartment: Space between the kneecap and the femur.
   

Cartilage covers the ends of these bones, providing cushioning during movement. When cartilage in one compartment wears down, it’s called unicompartmental osteoarthritis.

Tricompartmental osteoarthritis refers to damage in all three compartments of the knee. This widespread degeneration often occurs gradually over years, leading to bone-on-bone friction, decreased range of motion, and deformity.

Why Do Some People Develop Tricompartmental Osteoarthritis?

Multiple factors contribute to cartilage breakdown throughout the knee:

• Age: The risk of knee osteoarthritis increases with age.
  
• Previous injuries: ACL tears, meniscus injuries or fractures can change knee mechanics and accelerate wear.
  
• Excess weight: Obesity increases joint load, accelerating cartilage loss.
  
• Malalignment: Knock knees (valgus) or bowlegs (varus) concentrate stress on certain areas, promoting uneven wear.
  
• Genetics: Family history of osteoarthritis raises risk.
  
• Occupation and hobbies: Jobs or sports involving frequent kneeling, squatting, or heavy lifting stress the knee compartments.
  
• Comorbid conditions: Rheumatoid arthritis, gout, or metabolic disorders can damage cartilage.
  

Symptoms of Tricompartmental Knee Osteoarthritis

Because all compartments are involved, symptoms can be more pronounced than with unicompartmental arthritis. Common signs include:

• Persistent knee pain: Aching that worsens with weight-bearing activities and improves with rest.
  
• Morning stiffness: Difficulty bending or straightening the knee after waking up or sitting for long periods.
  
• Swelling: Excess synovial fluid causes the knee to look puffy or enlarged.
  
• Grinding or creaking: A sensation or sound (crepitus) when moving the knee.
  
• Instability or buckling: Feeling like the knee may give way.
  
• Deformity: Advanced cases may lead to a bowlegged or knock-kneed appearance.
  

If you notice these symptoms, schedule an evaluation early. Catching the disease in its moderate stage can prevent further cartilage loss and preserve mobility.

Diagnosing Tricompartmental Osteoarthritis

A combination of physical examination and imaging studies is used to diagnose and assess the severity of tricompartmental osteoarthritis. During the exam, a clinician will look for swelling, tenderness, range of motion, and knee alignment. They may perform specific tests to check ligament stability and evaluate gait.

Imaging tests:

• X-ray: Shows the degree of joint space narrowing, bone spurs (osteophytes), and alignment. Symmetric loss of space in all three compartments suggests tricompartmental disease.
  
• Magnetic resonance imaging (MRI): Useful if there’s suspicion of meniscal tears, cartilage lesions or ligament injuries.
  
• Ultrasound: Can detect joint effusion and assess soft-tissue structures around the knee.
  

Sometimes, your doctor may aspirate joint fluid to rule out infection or gout if swelling is pronounced or there are signs of inflammation.

Non‑Surgical Treatment Options

While tricompartmental osteoarthritis can be severe, many people find relief through non-surgical treatments. These approaches help manage pain and improve function.

Lifestyle and Self-Management

The following lifestyle adjustments can ease stress on your knees and support healing:

• Weight reduction: Losing weight reduces the load on the knee. Even a small amount of weight loss can improve symptoms.
  
• Exercise: Focus on low-impact activities like swimming, cycling or walking to strengthen muscles without excess impact. Consider working with a physical therapist to develop a program.
  
• Posture and gait training: Learn to move in ways that distribute load evenly through the knee.
  
• Heat and ice: Warm compresses ease stiffness; ice reduces swelling after activity.
  

Bracing and Assistive Devices

These devices help redistribute weight and make movement easier:

• Unloader braces: Shift weight away from the most damaged compartment to relieve pain.
  
• Canes or walking sticks: Help take pressure off the knee when walking.
  

Medications

Several medicines can relieve pain and inflammation:

• Acetaminophen: First-line pain reliever for mild to moderate pain.
  
• Nonsteroidal anti-inflammatory drugs (NSAIDs): Ibuprofen or naproxen relieve pain and inflammation; topical gels can ease knee pain with fewer systemic side effects.
  
• Duloxetine: An antidepressant that relieves chronic musculoskeletal pain.
  

Injection Therapies

Injections deliver relief directly into the joint:

• Hyaluronic acid (viscosupplementation): Lubricates the joint, improving shock absorption. Research shows these “knee gel shots” may relieve pain for months.
  
• Platelet‑Rich Plasma (PRP) therapy: Uses your own platelets to promote healing and reduce inflammation.
  
• Genicular Artery Embolization: A procedure that reduces blood flow to inflamed tissue and can decrease pain.
  

Physical Therapy and Exercise

A physical therapist can teach strengthening and flexibility exercises to support your knee:

• Quadriceps strengthening: Straight leg raises, wall sits and step-ups to build the front thigh muscles.
  
• Hamstring and hip exercises: Bridges, clam shells and side leg lifts to balance muscle strength.
  
• Range-of-motion exercises: Gentle stretching to maintain flexibility.
  

Surgical Options for Advanced Cases

When conservative measures fail and pain severely limits your life, surgery may be considered:

• Arthroscopy: Minimally invasive procedure to remove loose cartilage or repair torn meniscus.
  
• Osteotomy: Cutting and realigning the bone to shift weight away from damaged areas, used mostly in younger patients.
  
• Partial knee replacement: Replaces only the damaged compartments; not suitable for tricompartmental disease.
  
• Total knee replacement: Replaces all three compartments with an artificial joint. Considered when pain, stiffness and deformity are severe and other treatments have failed.
  

Daily Tips to Protect Your Knees

Because tricompartmental osteoarthritis involves all compartments, protecting your knee becomes even more important. Here are some day-to-day habits:

1. Choose low-impact exercises: Swimming, cycling or water aerobics allow you to strengthen your legs without pounding on your knees.
   
2. Use proper footwear: Supportive shoes or orthotic inserts can align your leg and relieve pressure on the knee.
   
3. Avoid prolonged kneeling or squatting: Use knee pads or take frequent breaks if you need to be on your knees.
   
4. Strengthen surrounding muscles: Strong quadriceps and hamstrings absorb shock and reduce strain on the joint.
   
5. Engage your core: A strong core improves posture and decreases stress on the knees.
   
6. Stay mindful of pain: Pain is a signal to slow down. Modify activities when you notice increased discomfort.
   

For more tips on knee care, see our article on how to reduce swelling in the knee quickly.

How Tricompartmental Osteoarthritis Differs From Other Types of Knee Arthritis

Unlike unicompartmental arthritis, which affects only one part of the knee, tricompartmental osteoarthritis damages all three compartments. This means cartilage is worn down on both the inside and outside surfaces of the knee as well as under the kneecap.

As a result, pain and stiffness tend to be more widespread and may be felt across the front, back and sides of the knee. Swelling is more likely because all parts of the joint capsule are irritated, and the knee may look visibly larger. Patients often report a feeling of heaviness or fullness in the joint.

Because the joint space is narrowed in multiple areas, the bones may rub against each other more readily. This can lead to the formation of bone spurs and deformities such as knock‑knees or bowlegs. Unicompartmental disease may respond well to targeted bracing and partial knee replacement.

In contrast, tricompartmental disease often requires a comprehensive approach that addresses the whole joint and sometimes leads to total knee replacement if conservative measures fail. Understanding these differences can help you and your care team choose the most appropriate treatments.

Coping With the Emotional and Psychological Impact

Chronic knee pain doesn’t just affect physical mobility; it can also take a toll on your mental well‑being.

People with tricompartmental osteoarthritis sometimes avoid activities they enjoy because of fear of pain or falling. This can lead to feelings of isolation, frustration and sadness. It’s normal to mourn the loss of previous abilities, but there are ways to cope:

• Stay connected: Maintain social connections through phone calls, video chats or activities that don’t strain your knees, such as board games or gentle walking groups.
  
• Focus on what you can do: Adjust activities rather than give them up entirely. For example, if running hurts, try cycling or swimming.
  
• Practice mindfulness: Techniques like deep breathing, meditation or journaling can help manage stress and improve your outlook.
  
• Seek professional support: Talking to a counselor or joining an arthritis support group can provide encouragement and practical advice from others facing similar challenges.
  

Remember, you are not your arthritis. Focusing on small victories—like walking a little farther or gardening for an extra 15 minutes—can boost confidence and make everyday life more enjoyable.

Frequently Asked Questions About Tricompartmental Osteoarthritis

Is tricompartmental osteoarthritis the same as end‑stage arthritis?
Not necessarily. While tricompartmental disease is more advanced than unicompartmental arthritis, many people still find relief with non‑surgical treatments.

End‑stage arthritis generally refers to severe cartilage loss and bone‑on‑bone contact throughout the joint that no longer responds to conservative care. Your doctor will assess the degree of cartilage damage to determine your stage.

Can I avoid knee replacement if I have tricompartmental disease?
Many patients manage symptoms successfully with weight loss, exercise, braces, and injections. Procedures such as viscosupplementation, platelet-rich plasma therapy, and genicular artery embolization may also provide substantial relief. A knee expert at Arthritis Knee Pain Centers can help you figure that out.

Surgery is considered when pain severely limits your daily activities and other treatments have failed.

What exercises are safe for tricompartmental osteoarthritis?
Low‑impact activities that strengthen muscles without pounding the joints are ideal. Swimming, cycling, tai chi and water aerobics build cardiovascular fitness while reducing stress on the knee.

Strengthening the quadriceps, hamstrings, glutes, and core improves joint stability. Always start slowly and consult a physical therapist for guidance.

Does weather affect my knee pain?
Some people notice increased pain or stiffness with changes in barometric pressure or cold weather. While research is mixed, staying warm and active can minimize discomfort. Consider using heat packs or exercising indoors during colder months.

If you have questions about your specific situation, don’t hesitate to reach out to a specialist. A personalized approach yields the best results.

Living Well With Tricompartmental Osteoarthritis

Knee osteoarthritis may be progressive, but there are many ways to manage symptoms and maintain an active lifestyle.

At Arthritis Knee Pain Centers, we specialize in non-surgical treatments that target the source of pain. Our team provides image-guided viscosupplementation, platelet-rich plasma injections, and genicular artery embolization to address inflammation and restore joint function. We also fit patients with custom braces and provide chronic care management to support long-term health.

You don’t have to live with constant knee pain. Schedule your screening for a no-charge, no-obligation assessment. Our specialists will evaluate your knee and recommend a personalized plan to keep you moving comfortably.