Knee osteoarthritis is a common cause of knee pain, stiffness and difficulty walking, particularly as you get older. It cannot be cured, but there are many non-surgical treatments that can ease your symptoms and help you stay active. [5]
Weight loss, exercise and physiotherapy have the strongest evidence and are the first steps for most people. Medicines, injections, braces and hydrotherapy can also help some people. If these options no longer control your symptoms, surgery may be considered.
At a Glance
- Knee osteoarthritis is the gradual wear of the cartilage that cushions your knee joint.
- Weight loss, exercise and physiotherapy are the foundation of treatment and have the strongest evidence.
- Pain relief, injections, braces and hydrotherapy may help some people, but each has limits.
- Some popular treatments, such as PRP injections and glucosamine, have shown less benefit in recent trials than previously thought.
- If non-surgical treatment no longer controls your symptoms, an osteotomy or a partial or total knee replacement may be considered.
What is knee osteoarthritis and how common is it?
Your joints go through a normal cycle of wear and repair throughout life. With ageing, the body’s ability to repair the joints declines, which leads to changes in their structure and shape. These changes can lead to joint problems such as osteoarthritis.
Knee osteoarthritis (OA) is a form of arthritis caused by the progressive loss of articular cartilage, the smooth layer that covers the ends of the bones. As the cartilage breaks down, it becomes rough and frayed, and the protective space between the bones narrows. When this happens, the bones can rub together and the joint becomes inflamed. [1]
Knee osteoarthritis is more likely to occur in people aged 50 and over, and it tends to worsen over time. According to the Australian Institute of Health and Welfare, knee osteoarthritis affects about one in five Australians over 45.
What are the symptoms of knee osteoarthritis?
Common symptoms of knee osteoarthritis include: [2]
- knee pain that develops gradually and worsens with activity
- difficulty walking
- knee pain at night
- pain after resting or sitting for a long time
- swelling and stiffness
- stiffness that makes it hard to fully straighten or bend your knee
- clicking, grinding or cracking with movement
- pain that worsens with changes in the weather.
What are the risk factors for knee osteoarthritis?
The exact cause of osteoarthritis is unknown, but several factors may contribute:
Age
Your likelihood of developing knee osteoarthritis increases as you age.
Genetics
If you have a family history of knee osteoarthritis, you are more likely to develop it as you get older.
Weight
Extra weight puts more stress on weight-bearing joints such as the knees and hips, which can increase your symptoms. [3]
Previous injury
Injuries such as an ACL rupture or a meniscal tear can increase the risk of osteoarthritis later in life.
Sex
Women over 50 are at greater risk of knee osteoarthritis than men.
Which non-surgical treatments can help knee osteoarthritis?
The following non-surgical treatments are commonly used for knee osteoarthritis.
1. Weight loss
Extra weight increases the load on your knees and can make osteoarthritis pain worse. In one study of overweight and obese older adults, each kilogram of weight lost reduced the load passing through the knee by about four kilograms with every step. [4]
Losing weight can ease the symptoms of osteoarthritis and also lowers your risk of other health problems, such as heart disease, type 2 diabetes and high blood pressure. Even modest weight loss, through a combination of diet and exercise, can help. [4] [5]
2. Medicines
Pain-relieving medicines can ease pain and discomfort and are often used alongside exercise and weight loss. [5]
a. Over-the-counter options
- Paracetamol is a common pain reliever for knee osteoarthritis.
- Non-steroidal anti-inflammatory drugs (NSAIDs), such as naproxen and ibuprofen, can also relieve pain. COX-2 inhibitors, such as meloxicam (Mobic) and celecoxib (Celebrex), are anti-inflammatories with fewer side effects on the stomach. [5] Anti-inflammatories can affect your stomach, kidneys and heart, so check with your GP or pharmacist before taking them regularly.
b. Prescription medicines
Opioid medicines, such as tramadol, tapentadol (Palexia) or oxycodone (Endone), are generally not recommended for osteoarthritis. If your doctor prescribes them, they should only be used for a short time, for example while you are waiting to see a specialist.
3. Exercise and physiotherapy
Physiotherapy and supervised exercise have been shown to reduce pain and improve knee function. [6] Your physiotherapist may recommend strength and flexibility exercises, which can:
- reduce stress on your knees
- improve the range of motion and flexibility of your knee
- strengthen the muscles of your legs
- improve how your knee works day to day.
Suitable exercises include stretching, walking, cycling, yoga, tai chi and water-based exercise such as swimming.
The GLA:D program
GLA:D (Good Life with osteoArthritis: Denmark) is an evidence-based exercise and education program for people with knee and hip osteoarthritis. It includes two education sessions and 12 supervised exercise sessions over about six weeks, with the aim of helping you manage your osteoarthritis. In Australia, the program has been associated with less pain, better function and less use of pain medicines. [7]
You can find out more and search for a local provider on the GLA:D Australia website.
4. Lifestyle changes
Staying physically active and adjusting your diet can help you manage the symptoms of knee osteoarthritis. Moderate physical activity may reduce pain.
If you play high-impact sports such as running or tennis, you may need to reduce how long or how hard you play, or switch to low-impact activities such as swimming or cycling.
5. Injections into the knee
Injections into the knee joint are another option when pain is not controlled by medicines or physiotherapy. Corticosteroid (steroid) and hyaluronic acid injections are the most common.
a. Steroids
Corticosteroid injections are strong anti-inflammatory medicines. They can ease pain and stiffness during a flare-up of osteoarthritis, but the relief is usually short-term. [8] Unlike steroid tablets, a steroid injection has limited effects on the rest of your body.
b. Hyaluronic acid (Synvisc, Durolane)
The fluid in your knee joint naturally contains hyaluronic acid, which helps lubricate the joint. In osteoarthritis, hyaluronic acid breaks down. An injection of hyaluronic acid may reduce pain and improve movement in some people, [9] and the effect may last several months.
c. PRP
PRP stands for platelet-rich plasma. A sample of your blood is spun in a centrifuge to concentrate the platelets, which contain growth factors, and the concentrate is injected into your knee. It is thought to reduce inflammation in the knee.
However, a randomised trial in Melbourne involving 288 people with mild to moderate knee osteoarthritis found that a PRP injection did not improve symptoms or joint structure at 12 months compared with a placebo injection of salt water. [14] You can read more in PRP Injections for Knee Osteoarthritis.
6. Hydrotherapy
Hydrotherapy is exercise in warm water. The buoyancy of the water reduces the load on your joints, so you can exercise without aggravating your knees. Hydrotherapy has been shown to improve pain and function in older women with knee osteoarthritis. [10]
7. Braces
If you have medial compartment osteoarthritis, which affects the inner side of the knee, your doctor may suggest an unloader brace. These braces are designed to shift pressure away from the inner part of your knee. [11]
8. Supplements
a. Curcumin
Curcumin is an anti-inflammatory compound found in turmeric. A short-term trial reported that curcumin eased pain from knee osteoarthritis, [12] but the evidence is limited.
b. Glucosamine and chondroitin
Glucosamine and chondroitin are commonly taken at doses of 500–1,500 milligrams a day. Large studies have found that their benefits for knee osteoarthritis are smaller than previously thought. [13]
What if non-surgical treatment does not help enough?
Osteoarthritis tends to worsen gradually over time. If non-surgical treatments no longer control your symptoms, surgery may be considered. Options include:
a. Knee osteotomy: the bone is cut and realigned to shift pressure away from the worn part of your knee. You can read more about realignment osteotomy.
b. Partial knee replacement: only the worn side of your knee is replaced with an artificial implant, and the rest of the knee and its ligaments are preserved. You can read more about partial knee replacement.
c. Total knee replacement: the damaged surfaces of the joint are removed and replaced with an artificial joint. You can read more about total knee replacement.
Each operation has its own risks, including infection, blood clots, stiffness and persistent pain, which should be weighed against the possible benefits.
Summary
Knee osteoarthritis can make everyday activities harder, and it is most common in adults over 50. Weight loss, exercise and physiotherapy are the foundation of treatment, and medicines, injections, braces and hydrotherapy may help some people. If your symptoms become more severe despite these measures, surgical options may be considered.
If you would like to discuss how this applies to your knee, you can book a consultation with Dr Vishal Pai.
References
Show all 14 referencesHide references
- Felson DT. 2006. Osteoarthritis of the knee. New England Journal of Medicine.
- Lespasio MJ et al. 2017. Knee osteoarthritis: a primer. The Permanente Journal.
- Coggon D et al. 2001. Knee osteoarthritis and obesity. International Journal of Obesity.
- Messier SP et al. 2005. Weight loss reduces knee-joint loads in overweight and obese older adults with knee osteoarthritis. Arthritis and Rheumatism.
- McAlindon TE et al. 2014. OARSI guidelines for the non-surgical management of knee osteoarthritis. Osteoarthritis and Cartilage.
- Fransen M et al. 2015. Exercise for osteoarthritis of the knee. Cochrane Database of Systematic Reviews.
- Barton CJ et al. 2021. Program evaluation of GLA:D Australia: physiotherapist training outcomes and effectiveness of implementation for people with knee osteoarthritis. Osteoarthritis and Cartilage Open.
- Law TY et al. 2015. Current concepts on the use of corticosteroid injections for knee osteoarthritis. The Physician and Sportsmedicine.
- Aggarwal A, Sempowski IP. 2004. Hyaluronic acid injections for knee osteoarthritis: systematic review of the literature. Canadian Family Physician.
- Dias JM et al. 2017. Hydrotherapy improves pain and function in older women with knee osteoarthritis: a randomized controlled trial. Brazilian Journal of Physical Therapy.
- Duivenvoorden T et al. 2015. Braces and orthoses for treating osteoarthritis of the knee. Cochrane Database of Systematic Reviews.
- Nakagawa Y et al. 2014. Short-term effects of highly-bioavailable curcumin for treating knee osteoarthritis: a randomized, double-blind, placebo-controlled prospective study. Journal of Orthopaedic Science.
- National Center for Complementary and Integrative Health. Glucosamine and chondroitin for osteoarthritis. NCCIH.
- Bennell KL et al. 2021. Effect of intra-articular platelet-rich plasma vs placebo injection on pain and medial tibial cartilage volume in patients with knee osteoarthritis: the RESTORE randomized clinical trial. JAMA.
Talk through your options for knee osteoarthritis
Dr Vishal Pai assesses knee osteoarthritis and can discuss both non-surgical and surgical options with you. You can arrange a consultation to talk about your symptoms, imaging and treatment options.
Written by Dr Vishal Pai
Vishal is an experienced knee surgeon based in Bayside, Melbourne. He consults at Sandringham Orthopaedic Specialists and operates at The Avenue Hospital and Calvary Holmesglen Private Hospital. His practice focuses on sports knee surgery, including ACL reconstruction and meniscal repair, as well as robotic knee replacement.