Twenty years ago, the words knee osteoarthritis meant putting up with knee pain until you couldn’t anymore, and then you were given a prosthesis. As prostheses lasted a relatively short time, they were reserved for the elderly, to avoid having to change the worn out prosthesis over time. In addition, there were hardly any therapeutic alternatives for knee osteoarthritis: it was either a prosthesis or nothing.
Fortunately, things have changed and treatments for knee osteoarthritis have evolved. Prostheses are more resistant and are fitted on younger people who want to lead an active life without suffering from knee pain. This includes doing sport (yes, you read correctly: you can do sport with a knee prosthesis), with all the benefits that physical activity brings. In addition, a multitude of new therapies for knee osteoarthritis have emerged.
In this article we tell you about all the treatment options for knee osteoarthritis. Some of them will doubtless be suitable for you.
What is knee osteoarthritis?
To understand the treatments for osteoarthritis, it is first necessary to understand how this disease occurs.
In short, osteoarthritis consists of wear and tear of the joint – especially cartilage, but also bone and other joint structures – which causes pain and stiffness.
Cartilage is a thin, elastic layer (between 2 and 5mm thick), a kind of padding that covers the bones which form the joints and allows them to slide together. Cartilage – together with the menisci, bone, ligaments and muscles – cushions the load that the knee supports due to the weight of the body and activities such as walking or running.
In general, all these structures regenerate quite well when they are injured or can be surgically repaired with relative ease… all, except cartilage. This is very poorly vascularized, that is, there is hardly any blood, so it has to be nourished from joint fluid, which is less rich in nutrients and oxygen than blood.
Cartilage is formed by a type of cell called chondrocytes, which are in a matrix formed by type II collagen, hyaluronic acid and other substances. With age, the matrix becomes less elastic, so the repeated loads break it and the chondrocytes are crushed. Then pieces of collagen and substances called cytokines are released, which further damage the tissues. Our defenses identify these substances as foreign and, in their attempt to “cleanse” them, further damage the cartilage. This is called autoimmune reaction.
In short, the body tries to repair and regenerate the cartilage, but it does not succeed. It is only able to form a scar. This scar can not withstand the loads and is not elastic; therefore, the joint becomes rigid.
Until now, medicine has not been more successful than the body in repairing the deterioration or, at least, stopping it. Once it began to cause damage, usually from 35-40 years of age, a person was condemned to progressive pain and stiffness. But, as we have said, things have changed…
Initial or advanced osteoarthritis? A treatment for each phase of knee osteoarthritis
As we have said, osteoarthritis is a progressive disease. Depending on the cartilage damage and the impact on the person’s life, treatment differs.
In early stages, when knee osteoarthritis is mild and pain does not prevent you from leading a normal life, the main thing is to maintain an appropriate weight and to exercise. Oral analgesics, topical anti-inflammatories (cream or similar) and capsaicin cream relieve pain.
In this stage it may be beneficial to take the damaged components of the matrix which forms the cartilage (for example, type II collagen), as well as to take or inject into the knee new drugs which prevent the autoimmune reaction that damages the cartilage and/or stimulates its regeneration.
In more advanced stages, when cartilage damage is greater, some people may benefit from arthroscopic surgery to remove damaged tissue and stimulate repair with healthy cartilage.
Finally, when all the cartilage has disappeared and joint deterioration is irreversible, the option is to replace the knee joint with a prosthesis.
Below, we will explain in detail each of these treatments.
Diet, exercise and pain relief in mild knee osteoarthritis
Of all the treatments that we’re going to tell you about in this article, losing weight (if necessary) and exercise are those that your knees will thank for you most:
- Lose weight. Obesity “kills” your knees, not only because of a purely mechanical problem, but also because certain substances released by the fatty tissue contribute to inflammation of the joint and cartilage damage. If you are already at your ideal weight, a varied and healthy diet (such as the Mediterranean one) is perfect for you. If you need to lose weight, a hypocaloric diet combined with physical exercise is the ideal way to achieve it. Forget about miracle diets and magic products. If necessary, consult a nutritionist.
- Do physical exercise. Physical exercise is the other pillar of the treatment of knee osteoarthritis in all stages of severity. Studies show that it lessens knee pain and improves mobility. Walking, cycling or swimming are some of the sports you can practice.
At those times when it hurts more, you can take painkillers or use topical anti-inflammatories (ie, applied to the skin of the knee). The latter have been shown to be effective in reducing mild pain and have fewer side effects than anti-inflammatory pills. Capsaicin cream is another option, although the first few times you apply it, it itches…be careful with your eyes!
Nutritional supplements: do they improve the symptoms of knee osteoarthritis?
The effect of various supplements on knee osteoarthritis has been studied, with contradictory results. There are studies that have found that they reduce pain and other symptoms of osteoarthritis, while others report no beneficial effect.
Among these supplements are, for example, type II collagen, Boswellia serrata, glucosamine and chondroitin sulfate (in Spain, these last two are considered to be drugs). Although their usefulness is not entirely clear, what all studies agree on is that these supplements have hardly any adverse effects.
Biological treatments for knee osteoarthritis
This type of treatment has gained prominence in recent times, thanks to the fact that they are not very complicated (so they allow for a quick recovery) and have the potential to stop osteoarthritis and even regenerate cartilage and other damaged tissues. They are therapies that are based on molecular biology and tissue engineering, with the following purposes:
- To provide the components of the cartilage matrix which deteriorates.
- To stop the destruction of cartilage.
- To regenerate cartilage as healthily as possible, injecting or implanting with very low invasive surgery different types of artificial matrices (hydrogels, porous sponges, nanofibres) with chondrocytes or cells that turn into them (stem cells) and stimulating their growth with growth factors, that enhance the production of cartilage.
Like all innovative treatments, these techniques have been subject to several studies. These studies show very promising results, although there is still much to research. In fact, one of the problems is that the protocols of each technique are still not clearly established, so that they can be uniform in all patients.
Some biological treatments include the injection of autologous serum proteins, the injection of platelet-rich plasma (PRP) and therapy with pluripotent mesenchymal cells derived from bone marrow, fatty tissue, blood, cartilage or umbilical cord.
Treatment of knee osteoarthritis with autologous serum proteins
As we have already seen, in knee osteoarthritis there is an inflammatory reaction. “Destructive” proteins, called proinflammatory cytokines (such as IL-1, IL-6, and TNF) are released, which attack the cartilage and destroy it causing pain.
There are other types of proteins in the blood that are anti-inflammatory (such as IL-1ra and sIL-1RII) and “constructive” (such as growth factors). If we inject a concentrated solution of all these beneficial factors into the knee, we counteract the action of harmful substances, which reduces pain and reduces the progress of osteoarthritis.
This technique is very recent, but studies with animals and the few existing studies with people show that it is effective in reducing pain.
Treatment of knee osteoarthritis with platelet-rich plasma
This is a technique that is based on the same theory as the previous one. Platelets contain growth factors and other proteins that promote healing and regeneration of injured tissues. The plasma is obtained by extracting blood from the patient and centrifuging it, so that it is more concentrated.
There are numerous clinical studies that support the efficacy and safety of platelet-rich plasma in knee osteoarthritis. These studies show that it improves pain-relief and knee function and that it is an alternative for mild-to-moderate osteoarthritis. However, the degree of effectiveness varies between different studies, possibly because the type of growth factors and their concentration vary according to the preparation.
Treatment of knee osteoarthritis with pluripotent mesenchymal cells
These are cells that have the ability to divide into other cells almost indefinitely, that is, to self-renew. In addition, they are capable of becoming cells of various tissues (eg, cartilage, bone, tendon, etc.). This is called differentiation.
There are different types of stem cells. The ones that are used to regenerate the tissue of the musculoskeletal system are mesenchymal stem cells. These cells can be obtained from different adult tissues, such as bone marrow or fat. Most commonly they are extracted from the bone marrow of the patient’s own pelvis (of course, with local anesthesia and sedation).
In knee osteoarthritis, treatment with stem cell injections slows cartilage damage, reduces pain and improves function. Generally, more than one injection is required. As with other recent techniques, there is is still much to be learned, but it is an alternative for many patients.
Hyaluronic acid injections (viscosupplementation)
Hyaluronic acid is a substance found in the knee that provides viscoelasticity to the fluid found inside the joint (synovial fluid). Hyaluronic acid injections have the purpose of returning this viscoelasticity to the liquid, lubricating the joint, cushioning loads and preventing the damaged cartilage areas from rubbing against each other. In addition, hyaluronic acid has anti-inflammatory and regenerative effects for some tissues, such as the meniscus.
Most scientific studies support the effectiveness of this technique for reducing pain and improving knee function. Many orthopaedic surgeons around the world use it and it is an option for people with mild or moderate osteoarthritis, or in more advanced osteoarthritis as a treatment to relieve the symptoms of osteoarthritis.
It can also be used in association with other biological therapies, such as platelet-rich plasma, to increase its effectiveness, or with pluripotent mesenchymal cells. The possible multiple combinations with these and other drugs, such as somatotropin or growth hormone, opens a wide range of treatment possibilities.
Arthroscopic surgery for knee osteoarthritis
Arthroscopy is a very widespread procedure to treat osteoarthritis of the knee. The goal is to “clean” the joint and remove damaged tissues (including part of the meniscus if it is torn, which frequently occurs in osteoarthritis).
Current evidence shows that, in isolation, it is not a better technique than conservative (ie, non-surgical) treatment in the vast majority of people with osteoarthritis. On the other hand, when it is combined with biological therapies for cartilage treatment, excellent results are achieved.
Replacement surgery: knee prosthesis
When osteoarthritis is very advanced, the option is to replace the joint with a prosthesis. Until recently, this procedure was reserved for elderly people with very limited mobility, in order to reduce pain and allow them to walk again.
This is no longer the case. Many people are physically very active and want to remain so for a long time, so knee prostheses are also an alternative for them when other treatments fail. It is no longer necessary to walk with a cane to opt for a prosthesis.
In this sense, not only have the people changed – who are now much more physically active – but also the prostheses and the surgical techniques themselves. For example, new techniques such as PSI (Patient Specific Instrumentation) allow the simulation of surgical interventions before they are carried out. The simulator allows the orthopaedic surgeon to establish the cutting and fixing points of the prosthesis in a precise and individualized manner for each specific patient. Your knee is not the same as your neighbour’s, right? This procedure brings precision and safety to the surgery… and, with a model made with a 3D printer you can see how your prosthesis will look before putting it on!
To finish, one final recommendation
Can you imagine what our final recommendation is? Yes; Consult with your doctor.
Everything we have set out here is for guidance only. Your doctor is the only one who can diagnose and treat your particular case. However, if you want to have a rough idea of what would be the best treatment for you based on your symptoms, fill out this questionnaire.
Of all the treatment alternatives for knee osteoarthritis that we have explained, there is doubtless one which is appropriate for you. Because living with knee pain is no longer an option.
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More interesting info:
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