Knee Osteoarthritis: Symptoms, Causes, Diagnosis, and Treatments

Knee osteoarthritis is the major cause of disability in people over 60 years of age. A recent study in 2020 by Lancet Discovery Science found out that the global prevalence of osteoarthritis is 16%. The figures are indicative of the large number of the global population suffering from this condition.

Since the disease is understood to be progressive, the need to catch the symptoms at early stages is the key to successful treatment.

What is knee osteoarthritis?

In laymen's terms, osteoarthritis is a condition where the natural cushioning between the joints faces wear and tear. It results in the joint bones rubbing against each other, causing pain, stiffness, swelling, and with time, development of contractures and bone spurs.

Knee osteoarthritis is also known as “degenerative joint disease of the knee.”

Osteoarthritis of the knee is the most commonly occurring form of arthritis. While it is more commonly observed in people above 45 years of age, younger people may also sometimes suffer from this condition. It has also been observed through various studies that women are more likely to face this condition than men.

There are two types of knee osteoarthritis:

Primary - Articular degeneration happens without an underlying cause.
Secondary - Happens as a consequence of a trauma, abnormal application of force on the joint, or conditions like abnormal articular cartilage-like rheumatoid arthritis.

What are the four stages of knee osteoarthritis?

Doctors usually classify the stages of knee osteoarthritis as follows:

Stage	Description
0	The knee appears normal and shows no signs of damage.
1 (Minor)	Patients show minor wear and tear of the knee joint. There may also be bone spur growths on the knee joint. However, for many patients, the stage may not be very painful. Treatment at this stage may only be in the form of lifestyle changes and supplements (like glucosamine).
2 (Mild)	Knee shows more bone spur growth. The patient may be experiencing some joint pain, stiffness around the joint, and a feeling of being uncomfortable when sitting for extended periods. The cartilage and soft tissues may still be healthy. However, some proteolytic breakdown of the cartilage matrix may be noted. Treatment methodology involves plans to stop the progression of the disease. Pain-relieving therapies may be prescribed along with braces and knee supports and supplements (e.g., Glucosamine).
3 (Moderate)	The cartilage shows signs of erosion. Additionally, the gap between the bones is narrowed, causing high levels of pain to the patient when walking. The synovial fluid may show proteoglycan and collagen fragments, and the joint may get rougher. The inflammation may result in frequent pain to the patient. There may also be popping sounds when walking. Treatment involves over-the-counter pain-relieving medications, therapies, weight loss. If the pain continues to grow, the patient may be given hyaluronic acid injections in the knee joint to increase mobility. Bone osteotomy and / or realignment surgery may also be beneficial.
4 (Severe)	The space within the joint is considerably reduced, causing severe wear and tear of the cartilage. This leads to chronic inflammation, decreased synovial fluid, extreme friction between the joints, and inability to move without extreme pain. This stage also shows the development of more bone spurs which may cause severe pain to the patient when moving. The treatment may involve knee replacement surgery, bone osteotomy and / or bone realignment.

Since osteoarthritis is a progressive disease, it may grow from one stage to the next if left untreated. The final stages of the disease may leave a patient disabled with a complete inability to walk.

It is therefore advisable to consult your doctor when you notice the early signs of knee pain or other symptoms.

What are the symptoms of knee osteoarthritis?

Osteoarthritis is a progressive disease, and a normal progression may be confused for a flare-up.

However, overexerting the knee, being involved in activities that cause pressure on the knee joint, repetitive motions, sudden weight gain, or even extreme cold weather may increase the level of discomfort in a patient.

Unfortunately, osteoarthritis is a progressive disease and may lead to complete blockage of movement if not treated timely.

The pain as well as the intensity of other symptoms varies from one patient to the other and may get more debilitating with time.

Common symptoms include:

Knee pain that is mild at first but worsens with time
Knee pain increases in intensity with activity
Stiffness and swelling around the knee joint
Inability to move the joint after prolonged sitting/resting
The joint feels warm to touch
Decrease in mobility
Cracking sound in the knee while moving

What are the causes of knee osteoarthritis?

Aging is the most common cause of osteoarthritis. A big percentage of adults develop a certain degree of osteoarthritis after an age.

Following are the known risk factors for developing arthritis of the knee:

Age - This is because the cartilage’s self-healing capacity decreases as a person gets older.
Heredity - Certain genes may make a person more prone to developing knee osteoarthritis.
Gender - Women above the age of 50 are more likely to get this condition than men.
Weight - Being overweight/obese increases the pressure on joints.
Stress-related injuries - This is commonly observed in people involved in certain types of activities/ jobs such as weightlifting, and constant kneeling on the floor.
Sports - High-intensity sports like soccer, tennis, and running, may increase the chances of knee injury resulting in osteoarthritis.
Other conditions - Certain pre-existing diseases like rheumatoid arthritis, and metabolic disorders, may increase the chances of osteoarthritis.

How is knee osteoarthritis diagnosed?

Your doctor may start the diagnosis with a physical examination. He may also ask you questions on:

Your medical history
Family history of arthritis and similar conditions
What makes the pain better or worse
Your occupation and if it involves long hours of pressure on the knee

In addition to these, the orthopaedic specialist may order the following tests:

X-Rays to show damage to the bone and cartilage
MRI scans
Blood tests to rule out conditions like rheumatoid arthritis or other hormonal issues

What are the treatment options for knee osteoarthritis?

The primary goal of treatment is pain management and restoring mobility. Treatment methodology hence begins with conservative techniques followed by surgical intervention if conservative treatment has become ineffective.

Conservative treatment options include:

Medications to slow down the progression and reduce inflammation and pain
Weight loss
Exercises to strengthen the muscles around the knee joint. This helps to make the joint more stable too
Corticosteroid injections may help relieve inflammation
Hyaluronic acid injections for lubricating the joint
Topical creams and ointments along with supplements
Supportive devices like knee braces
Occupational and physical therapy

Surgery techniques include the following:

Arthroscopy - This minimally invasive surgery (MIS) procedure is performed by making small incisions and using a telescope-like instrument (called an arthroscope) to remove damaged cartilage and repair tissue damage. It is preferably done on patients younger than 55 years of age. Post-surgery recovery is fast.

Osteotomy - This procedure is done to remove knee alignment. It is recommended if the damage is limited to one area of the knee or if a broken knee has not healed well.

Arthroplasty (joint replacement surgery) - As the name suggests, the joint is replaced by artificial parts (made of metal or plastic). It is usually recommended for cases of severe osteoarthritis and for people above 55 years of age.

Book an appointment at Pantai Hospitals

The caring and multidisciplinary team of healthcare professionals are available for consultation and to provide the best care. Get in touch with us to find out more about Orthopaedic Services at your nearest Pantai Hospital.

Pantai Hospital Malaysia is accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.

References

Global, regional prevalence, incidence and risk factors of knee osteoarthritis in population-based studies, Available at https://www.thelancet.com/journals/eclinm/article/PIIS2589-5370(20)30331-X/fulltext [Accessed on 1 March 2022]
Knee osteoarthritis, Available at: https://www.ncbi.nlm.nih.gov/books/NBK507884/ [Accessed on 1 March 2022]
Knee osteoarthritis- causes, symptoms, and treatments, Available at: https://www.webmd.com/osteoarthritis/ostearthritis-of-the-knee-degenerative-arthritis-of-the-knee [Accessed on 1 March 2022]
Osteoarthritis- Diagnosis and treatment, Available at: https://www.mayoclinic.org/diseases-conditions/osteoarthritis/diagnosis-treatment/drc-20351930 [Assessed on 1 March 2022]
Osteoarthritis of the knee, Available at: https://www.medicalnewstoday.com/articles/310579 [Accessed on 1 March 2022]
What is knee osteoarthritis, Available at: https://www.arthritis-health.com/types/osteoarthritis/what-knee-osteoarthritis#:~:text=Knee%20osteoarthritis%20is%20a%20condition,from%20joint%20friction%20and%20impact. [Accessed on 1 March 2022]
Arthritis in the knee- 4 stages, Available at: https://www.ibji.com/blog/orthopedic-care/arthritis-in-knee-4-stages-of-osteoarthritis/ [Accessed on 2 March 2022]