Which knee injection is right for me?

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Steroid Vs Hyaluronic Acid Vs Arthrosamid

If you have knee osteoarthritis and are considering an injection, you may have come across several different treatment options.

At Bristol Joint Injections, the three main injections we use for knee osteoarthritis are corticosteroid, hyaluronic acid and Arthrosamid (iPAAG).

These treatments are quite different. They work in different ways, have different evidence supporting their use and differ in their potential duration of benefit and cost.

There isn't one knee injection that is right for everybody.

Before recommending an injection, we assess your knee, your symptoms, previous treatment, medical history and what you hope to achieve.

The first question isn't necessarily “Which injection should I have?” but “Is an injection appropriate for my knee at all?”

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Do I Need A Knee Injection?

Not necessarily.

Exercise, strengthening and maintaining physical activity are important parts of managing knee osteoarthritis. Weight management can also improve pain and function where this is appropriate.

For some people, however, pain continues to interfere substantially with walking, exercise, sport, work or everyday life despite appropriate treatment. This is when an injection may become one of the options to consider.

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Corticosteroid

Corticosteroid, commonly shortened to steroid, is an anti-inflammatory medication.

Steroid injections have been used for many years in the treatment of painful joints and may be particularly useful when an osteoarthritic knee is painful, irritated or swollen.

The injection aims to reduce inflammation and pain. It does not repair cartilage or reverse osteoarthritis.

When it works, improvement can occur relatively quickly. Although individual responses vary considerably, most people experience 6-12 weeks of pain relief allowing increased function and as ana aid to rehabilitation.

Steroid may be worth discussing when:

• Your knee is particularly painful or inflamed

• There is an associated joint effusion or swelling

• Pain is preventing effective rehabilitation

• Relatively rapid, short-term pain reduction is the priority

• Other appropriate pain treatments have been ineffective or unsuitable

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Hyaluronic Acid

Hyaluronic acid is naturally present in joint fluid and contributes to its lubricating and shock-absorbing properties.

An injection uses a manufactured form of hyaluronic acid within the knee joint. You may also hear this described as viscosupplementation.

It works differently from corticosteroid and is not primarily being used as a powerful anti-inflammatory medication.

Where someone responds, improvement tends to develop more gradually than with steroid. Some patients report useful improvement in pain and function, while others experience little or no benefit.

One of the benefits of hyaluronic acid injections is that when they work, they can be repeated again and again over time to provide longer term relief from symptoms.

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ARTHROSAMID (iPAAG)

Arthrosamid is different from both steroid and hyaluronic acid.

It is an injectable 2.5% polyacrylamide hydrogel, usually abbreviated to iPAAG.

Unlike a medication that is gradually cleared from the joint, the hydrogel is non-biodegradable and integrates with the synovial tissue lining the knee.

It is therefore useful to think of Arthrosamid as a long-lasting injectable hydrogel treatment rather than another version of a steroid injection.

Arthrosamid isn't intended to produce the rapid anti-inflammatory effect associated with corticosteroid. Improvement can develop progressively following treatment, often taking 6-12 weeks before improvements can be fully established.

Longer-term results are now becoming available. Studies have reported improvements in pain and function continuing for up to five years following a single iPAAG injection in some patients. These findings should not be interpreted as meaning that one Arthrosamid injection is guaranteed to work for five years.

Arthrosamid has a newer and smaller evidence base than corticosteroid or hyaluronic acid.​

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So Which Injection Might Suit Me?

A painful, swollen or inflamed knee:

If your knee has become particularly painful and contains a significant effusion, we may consider aspirating the excess fluid and, where appropriate, using corticosteroid.

Pain is preventing rehabilitation:

If pain is preventing you from exercising or participating effectively in rehabilitation, short-term symptom reduction with corticosteroid may sometimes provide a useful window in which to improve strength and function. Some people benefit from having a combine steroid and hyaluronic acid injection, and we are happy to discuss this option with you.

Looking beyond a short-term steroid injection:

Some patients don't want repeated corticosteroid injections or have previously had only short-lived benefit. Hyaluronic acid may then be a good alternative.

Looking for a longer-term non-surgical option:

Arthrosamid may be considered by patients seeking a longer-term treatment who understand that it is a newer and generally more expensive option.

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Is Arthrosamid Better Than Hyaluronic Acid?

They are very different injections and provide their benefits in different ways. Some people prefer the shorter terms repeatability of hyaluronic acid, whereas some prefer a longer acting one-off injection if that is suitable for them.

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Is Hyaluronic Acid Better Than Steroid?

There isn't a simple yes or no answer.

Steroids have their clearest role in short-term symptom relief, particularly where inflammation is contributing to symptoms. Hyaluronic acid generally provides longer-lasting improvements but is less ideal for an acutely painful joint.

Why Do You Use Ultrasound Guidance?

At Bristol Joint Injections, all three treatments are performed under ultrasound guidance.

Ultrasound allows us to see the relevant anatomy and guide the needle into the knee joint. It also allows us to identify an effusion and, where appropriate, remove excess joint fluid before performing an injection. Many people find ultrasound-guided injections less uncomfortable than non-guided injections.

If you have previously had a non-guided injection which did not provide benefit, then a guided injection is often considered the most appropriate next step in the management of your knee pain.

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Do Injections Replace Exercise?

No.

Whichever injection you choose, maintaining or improving the capacity of the knee remains important.

An injection that successfully reduces pain can provide an opportunity to increase physical activity, improve quadriceps and lower-limb strength, progress rehabilitation, return gradually to valued activities and improve confidence in the knee.

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Will Any Of These Injections Regrow My Cartilage?

No.

Steroid, hyaluronic acid and Arthrosamid have not been shown to regrow lost articular cartilage or reverse established knee osteoarthritis.

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What If I Need A Knee Replacement?

If osteoarthritis is substantially affecting your quality of life despite appropriate non-surgical management, an orthopaedic assessment for knee replacement may be the more appropriate next step.

For some people, however, pain continues to interfere substantially with walking, exercise, sport, work or everyday life despite appropriate treatment. This is when an injection may become one of the options to consider.

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How Do We Decide?

At Bristol Joint Injections, we don't start by deciding which product to inject. We start by assessing you and your knee. Our clinicians have many years experience of managing knee pain in Bristol in both the NHS and in private practice.

We consider:

• Your diagnosis

• Your symptoms

• Whether your knee is swollen

• How osteoarthritis is affecting your life

• Previous rehabilitation

• Previous injections and their effects

• Relevant medical conditions

• Your imaging where appropriate

• Your expectations from treatment

• The risks and limitations of each option

• Cost

• Whether another treatment or specialist opinion would be more appropriate

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Knee Injection Treatment In Bristol

Choosing between corticosteroid, hyaluronic acid and Arthrosamid isn't simply a matter of selecting the injection advertised as lasting the longest.

They are different treatments with different purposes, evidence, risks and costs.

At Bristol Joint Injections, we can assess your knee, review relevant imaging and discuss the advantages and limitations of each option.

If you are considering an injection for knee osteoarthritis but aren't sure which option is appropriate, contact Bristol Joint Injections to arrange an assessment.