The best injection for knee pain depends on what is causing the pain, how advanced the problem is, and what you want treatment to achieve.
For knee osteoarthritis, cortisone may be considered when short-term relief from inflammation is the priority. Hyaluronic acid (HA) is intended to improve lubrication within the joint, although current NICE guidance does not recommend it for routine osteoarthritis management. PRP uses components of your own blood and is another option sometimes considered for knee osteoarthritis, but NICE states that evidence for its effectiveness remains limited in quality.
There is therefore no single knee pain injection that is best for everyone. A clinical assessment should come first so that treatment can be matched to the cause of your symptoms.
Why Are Knee Injections Used?
Knee injections deliver treatment directly into or around the affected joint. They are most commonly considered when knee pain has persisted despite measures such as appropriate exercise, physiotherapy or medication.
Knee osteoarthritis is a particularly common reason for considering an injection into the knee for pain. Arthritis can cause pain, stiffness, swelling and reduced mobility, making activities such as walking and climbing stairs difficult.
At Alton Pain Clinic, patients considering knee injections are assessed before treatment, and injections are performed using ultrasound guidance.
Three options patients commonly ask about are cortisone, hyaluronic acid and PRP.
Cortisone Injections: Best for Short-Term Inflammation Relief?
A cortisone injection, also called a corticosteroid or steroid injection, works primarily by reducing inflammation.
For someone with an inflamed, painful or swollen arthritic knee, reducing inflammation can provide a period of improved comfort. This may make everyday movement easier and can also provide an opportunity to participate more comfortably in therapeutic exercise.
Cortisone generally works relatively quickly compared with the other treatments discussed here. However, its effects are temporary.
NICE recommends considering intra-articular corticosteroid injections for osteoarthritis when other pharmacological treatments are ineffective or unsuitable, or when an injection is needed to support therapeutic exercise. Patients should be told that relief is short-term, typically around 2–10 weeks.
A cortisone injection may therefore be considered when the immediate priority is controlling an inflammatory flare rather than achieving a long-lasting structural change to the joint.
Hyaluronic Acid Injections: How Are They Different?
Hyaluronic acid is naturally present within joint fluid and plays a role in lubrication. A hyaluronic acid injection introduces a gel-like substance directly into the knee joint with the aim of improving lubrication and reducing discomfort.
This is fundamentally different from cortisone. Rather than primarily suppressing inflammation, HA is intended to improve the environment and lubrication within the joint.
However, it is important to present the evidence clearly. Current NICE guidance says not to offer intra-articular hyaluronan injections for osteoarthritis, concluding that the evidence did not demonstrate sufficient benefit for pain, physical function or quality of life.
Hyaluronic acid remains available privately and is offered by some clinics, including Alton Pain Clinic. Patients considering it should discuss the potential benefits, limitations, cost and current clinical guidance before deciding whether it is appropriate for them.
What About PRP for Knee Pain?
Platelet-rich plasma (PRP) takes a different approach again.
A sample of the patient’s own blood is processed to produce plasma containing a concentrated level of platelets. This preparation is then injected into the affected area.
PRP is sometimes considered for people with early or mid-stage knee osteoarthritis. Unlike cortisone, it is not primarily intended to suppress inflammation rapidly, and unlike hyaluronic acid, it is not a joint lubricant.
There is growing interest in PRP, but there is still uncertainty surrounding its effectiveness. NICE states that there are no major safety concerns but that the quality of evidence regarding efficacy is limited. It recommends special arrangements for clinical governance, consent and audit or research.
Patients considering PRP injection treatment should therefore understand that it is not a guaranteed solution for knee arthritis.
Cortisone vs Hyaluronic Acid vs PRP
Cortisone | Hyaluronic Acid | PRP | |
|---|---|---|---|
What is it? | Corticosteroid medication | Gel-like joint lubricant | Concentrated platelets from your blood |
Main aim | Reduce inflammation | Improve joint lubrication | Encourage biological responses within the joint |
Speed | Usually relatively fast | More gradual | Typically gradual |
Best considered for | Short-term inflammatory symptom relief | Selected private patients after discussion of evidence | Selected patients, often with early/mid-stage OA |
NICE position | Consider for short-term OA relief in certain circumstances | Do not offer for OA | Efficacy evidence limited in quality |
Does it cure arthritis? | No | No | No |
The important point is that knee injections should not be chosen simply because one treatment sounds newer or more advanced.
So, Which Knee Pain Injection Is Right for You?
If your knee is painful and inflamed and short-term symptom relief is the priority, cortisone may be considered. If you are exploring private alternatives, you may come across hyaluronic acid or PRP, but the limitations of the evidence and relevant clinical guidance should form part of the discussion.
Your age, medical history, diagnosis, severity of joint changes, previous treatments and personal goals can all affect the decision.
It is also important to remember that an injection is usually only one part of managing knee osteoarthritis. NICE identifies therapeutic exercise as a core treatment, with weight management also important for people who are overweight or living with obesity.
Knee Injections at Alton Pain Clinic
Alton Pain Clinic provides several ultrasound-guided options for knee pain, including cortisone, hyaluronic acid and PRP, as well as other treatments such as Cingal and Arthrosamid.
Rather than assuming that one injection is right for every painful knee, the starting point should be an assessment to understand what is causing your symptoms.
Ultrasound guidance is used by the clinic when carrying out knee injections, allowing the clinician to visualise the joint and guide needle placement in real time.
The Bottom Line
There isn’t one universally best injection for knee pain. Cortisone has an established role for short-term relief in appropriately selected people with osteoarthritis. Hyaluronic acid is available privately but is not recommended by NICE for managing osteoarthritis. PRP is another option, although NICE considers the evidence for effectiveness limited in quality.
If knee pain is affecting your mobility or quality of life, a proper assessment can help establish the cause and determine whether a knee injection (or another treatment altogether) is the most appropriate next step.
This article is intended for informational purposes only and should not replace professional medical advice. If you are experiencing persistent symptoms, please consult a qualified clinician.