Knee arthritis is common — a recent study found twice as many people have it as ten years ago. The most effective treatment is exercise and weight loss, but injections — cortisone, hyaluronic acid, or PRP — have a role in some cases. So, can we use hyaluronic acid and PRP together, and is the combination better than either alone?

For each injection on its own, see our hyaluronic acid guide and PRP injection guide.

What is PRP?

PRP — platelet-rich plasma — comes from your own blood, taken from the arm and spun in a centrifuge to separate the red cells from the plasma. The plasma, rich in growth factors, is injected into the knee to reduce inflammation and pain. Over 23 high-level studies show PRP reduces pain and improves activity in knee arthritis. Recent evidence suggests that higher platelet concentrations are more effective than lower ones, which is why second-generation systems such as Arthrex ACP Max deliver a higher dose in a single injection.

What is hyaluronic acid?

natural gel injection

Hyaluronic acid is a natural substance in healthy joints and bones, forming the building blocks of cartilage. Injected into a joint, it improves lubrication and reduces inflammation. Like PRP, it eases knee arthritis — and high-molecular-weight types such as Durolane outperform weaker products such as Ostenil Plus.

What about both in one injection?

It makes intuitive sense: if either injection reduces pain, combining them might reduce it even more. Together, PRP and hyaluronic acid may improve cell communication and tissue healing. So what do the knee arthritis studies show?

On their own, we think PRP is slightly better than hyaluronic acid. But a study found that combining both in one injection was even better — when comparing combined PRP-plus-hyaluronic acid against hyaluronic acid alone, there was a clear advantage for the combination at 3, 6, and 12 months. Another study compared the combination with PRP alone and found the same: better pain scores at 12 months, with fewer side effects.

So why not combine them every time?

A few reasons. First, the combined injection costs more than either alone. Second, some people can’t have PRP (a blood disorder such as low platelets), while others are allergic to hyaluronic acid. Third, we’d like more evidence before making it a blanket recommendation. Still, the early findings are genuinely exciting and may reshape how we treat knee arthritis.

One newer system combines PRP and hyaluronic acid in a single syringe — but it uses a low-molecular-weight hyaluronic acid and a low platelet count, so it isn’t ideal. A better approach combines a high-concentration PRP (Arthrex ACP Max) with a high-molecular-weight hyaluronic acid (Durolane).

Whether you have one injection or both, have it done under ultrasound guidance.

Frequently asked questions about hyaluronic acid and PRP

Can you have PRP and hyaluronic acid in one sitting?

Yes. Dr Masci often injects high-molecular-weight hyaluronic acid (Durolane) and PRP together in one injection, followed by a second PRP injection 2–4 weeks later. The exact protocol depends on the system used.

Can I have PRP after a course of hyaluronic acid?

Yes. You can have PRP after hyaluronic acid — they don’t have to be given at the same time.

Does the combination work for bone-on-bone arthritis?

It can, but the effect is smaller with more severe arthritis. Results are best in mild-to-moderate disease, though even advanced knees may still benefit.

Is a combination of HA and PRP suitable for tendons?

Generally no. For most tendon injections, we avoid hyaluronic acid, with specific exceptions. The combination is mainly a knee (and hip) arthritis approach.

Which should I try first — one injection or both?

We usually suggest a single high-molecular-weight hyaluronic acid injection first, as it needs only one visit. Second-line is PRP, or the PRP-plus-hyaluronic-acid combination. Discuss the pros and cons with your doctor.

Final word from Sport Doctor London about hyaluronic acid and PRP

Combining hyaluronic acid and PRP is still somewhat controversial, but the evidence suggests the combination may beat either alone for knee arthritis. Dr Masci typically advises two standard PRP injections with one Durolane injection for knee and hip osteoarthritis, or, using Arthrex ACP Max, a single PRP injection combined with Durolane.

To book a one-stop knee or hip injection in London, contact the team here or call +44 (0) 203 488 0350. Review the self-pay fees here.

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