PRP for Knee Osteoarthritis

Osteoarthritis (OA) is the most common form of arthritis, and the knee is one of the joints it affects most often. Over time, the smooth cartilage that cushions the ends of the bones thins and roughens, and the whole joint — including the bone, joint lining and surrounding soft tissue — changes in response.

It is not simply "wear and tear". Age, previous knee injuries (such as meniscus or ligament tears), body weight, genetics and muscle strength all play a role, which is why OA is also common in active people and former athletes.

Common symptoms

• Pain in or around the knee, often worse with activity, stairs or squatting
• Stiffness, especially first thing in the morning or after sitting
• Swelling or a feeling of fullness in the knee
• Grinding, clicking or creaking with movement
• Reduced range of movement or difficulty straightening the knee
• A feeling that the knee is weak or may give way

For most people, the most effective long-term treatment for knee osteoarthritis is a structured exercise programme to strengthen the muscles that support the knee, together with weight management where relevant and education about the condition. These remain the foundation of care whether or not you have any injections.

Injection treatments such as PRP may be considered when symptoms are not settling despite a well-structured exercise and rehabilitation programme. They are used alongside — not instead of — your rehabilitation.

Platelet-Rich Plasma (PRP) therapy concentrates your own platelets and growth factors — extracted from a simple blood draw — and injects them into the knee joint. In osteoarthritis, it aims to support the joint environment and reduce pain and stiffness, without surgery.

Research on PRP for knee osteoarthritis is still developing and results are mixed: some studies report improvements in pain and function, while others show no clear benefit over a placebo injection, and PRP preparations differ between studies. Response varies between individuals and improvement in symptoms is not guaranteed. Dr. Ganda will talk you through the current evidence and whether PRP is a reasonable option for you.

For a general overview of PRP and the other conditions it is used for, see the PRP therapy patient guide.

This is a general guide only. Suitability is decided at your consultation after a full assessment.

1. Step 1

   Assessment and diagnosis

   A full history and examination of your knee. Imaging such as an X-ray may be requested to confirm the diagnosis and its severity, after which an individualised treatment plan is discussed with you.

2. Step 2

   Blood draw

   Blood is drawn from your arm, much like a routine blood test.

3. Step 3

   Preparation

   Your blood is spun in a centrifuge (a machine that separates blood into its parts) to concentrate the platelets. The concentrated platelets are collected in a sterile syringe.

4. Step 4

   Ultrasound-guided injection

   The PRP is injected into the knee joint while Dr. Ganda watches on ultrasound in real time, so it reaches exactly the right spot.

Most patients need a course of three PRP injections, spaced about one week apart, with your progress reviewed at each visit. The course is completed with one injection of hyaluronic acid — a gel-like substance that lubricates and cushions the joint (sometimes called viscosupplementation).

Injections are combined with an exercise or physiotherapy programme, which is an important part of your recovery. Your treatment plan is individualised and fully discussed at your first consultation.

PRP is one of several injection options for knee osteoarthritis. Each has a different purpose, and the right choice depends on your symptoms, the severity of your OA and your goals.

After each knee injection you may have mild swelling, soreness and stiffness in the knee. This is expected and usually settles within 2–3 days with rest, elevation and ice. Paracetamol (e.g. Panado) is fine for discomfort.

You can return to normal daily activities straight away. Higher-impact activities such as running are reintroduced gradually, guided by your rehabilitation programme.

PRP is considered a safe procedure with a low risk of complications. Because it is made from your own blood, there is no risk of rejection or of catching a disease from donor products. As with any injection, there is a small risk of infection; this is rare, and strict sterile technique is used to prevent it.

• For the first 48 hours, avoid strenuous activity and sport — such as running, hiking, swimming or dancing — and anything that increases your pain.
• Until your next session, avoid high-load or impact exercise involving the treated area. Walking, daily activities and the rehab exercises prescribed for you are fine.
• You can usually drive afterwards. If your right leg was treated and it is sore, arrange a lift home.
• Avoid anti-inflammatory medicines (e.g. ibuprofen, diclofenac, Disprin/aspirin) for 1 week before and 2 weeks after each injection, as they can reduce the effect of PRP — unless they have been prescribed to you for another condition.
• Paracetamol (e.g. Panado) is safe to take for pain.