Platelet Rich Plasma Injections (PRP)

What Is Platelet Rich Plasma?

Our blood consists of 3 major components – red blood cells, white blood cells, and plasma. Whole blood contains all 3 of these components mixed together and in varying concentrations. The plasma contains acellular structures called platelets, together with molecules that function as clotting factors and growth factors.

If we place whole, unclotted blood in a centrifuge (a machine used to separate blood) and “spin it down”, we are able to distinguish 3 different layers. The red blood cells are the heaviest and sink to the bottom, while the white cells and plasma sit above this. The “clear” plasma, including the platelets, is then found between these two distinct layers.

Various techniques have been developed to concentrate the plasma and increase the relative concentration of platelets compared to that of our original whole blood. The absolute number of platelets in the plasma is dependent on the platelet concentration and the volume of whole blood that is taken from the patient.

What Do Platelets Do?

Platelets circulate freely within our vascular system. When there is an injury, the platelets become activated and stick to one another. This forms a mesh-like structure that traps other cellular material to it and forms a clot. This clot then helps to stop the leakage of contents out of the vascular system, i.e. stops the bleeding.

The clot also traps the contents of the plasma. The platelets are also activated to release their alpha granules. These contain a host of growth factors that stimulate healing in this area. These combine with other, free-floating, growth factors from the plasma, which are also trapped in the clot. This area then becomes a site for healing and angiogenesis – new vessel formation.

What Are The Clinical Uses For Platelet Rich Plasma?

PRP was first used in maxillofacial surgery to help the incorporation of bone grafts. Its use has now extended to the treatment of acute muscle and ligament tears, chronic muscle and ligament tears, chronic wound healing, and intra-articular use for degenerate joints.

  • Acute injuries – the addition of a high concentration of PRP to the area of injury has shown, in some studies, to result in faster healing and a quicker return to activity.
  • Chronic injuries – chronic injuries result in the formation of scar tissue and this often results in chronic pain. PRP is thought to stimulate/reinvigorate the healing process, resulting in the chronic scar tissue being replaced by healthier tissue.
  • Chronic wound healing – PRP in a gel or paste form has been shown to increase the chances of healing chronic wounds.
  • Intra-articular use – although the mechanism is poorly understood, an injection of PRP intra-articularly can produce a degree of pain relief and stiffness in some people. We reserve the use of intra-articular injections into the knee for patients with an advanced stage of degenerative disease. PRP works best on the earlier stages of arthritis with less effect when there is complete joint space loss (grade IV arthritis)

Our latest research (review of 225 patients) showed that 60% of the patients gained some relief from their continual symptoms. The duration of relief lasted from 1 month to 3 years.

Will PRP Help Me?

There are no randomised control trials to definitively say that PRP will cure your pain. However, where other modes of non-surgical treatment have failed, PRP remains as an alternative trial therapy. In certain conditions, PRP may be tried as first-line/initial therapy.

What Does The PRP Procedure Entail?

You will be required to fast (do not eat or drink) for 4 hours prior to your appointment (you may drink water only). Once you arrive at our consultation rooms, approximately 15 minutes prior to your booked appointment, you will be given special blood tubes for your blood to be drawn. We will then refer you to the laboratory (Ampath) where your blood will be taken by expert phlebotomists. Once your blood has been taken, you are then free to eat and drink.

You will then give the tubes of blood, which will be marked with your name, to our nursing sister. She will place it in the centrifuge and spin it down. The platelet-rich plasma is then carefully removed in a sterile procedure, and placed separately in a new container. Once we have collected enough PRP, we discard the remaining blood and platelet-poor plasma.

The PRP is then injected into your knee/s using an aseptic technique.

Depending on whether you are having one or two knees done, we will draw approximately 30-60mls of blood from you and will get 2-6mls of PRP for each knee (taking into consideration that everyone has different platelet levels).

How Many Injections Will I Need?

We usually recommend 2-3 injections over the course of 3-4 weeks.

We suggest that you make two appointments, to begin with, 10-14 days apart. If you find that the therapy is working well for you, you can make an appointment for a 3rd injection. We also offer a 4th (top-up) injection 6 months following the last injection.

You can repeat the therapy on a yearly basis as needed.

What Medication Must I Notify You About?

Please notify us if you are using any chronic medication, especially blood-thinning medication (e.g.: Warfarin, Aspirin, Ecotrin, or anti-inflammatory drugs). Please also notify us if you are on any medications for rheumatoid arthritis.

What Are My Limitations Post Injection?

After the injection, we suggest that you do the activities that you were doing before the injection. There are no formal limitations, but we recommend that you do not overdo anything, but rather gradually build up physical activity.

Do I Need To Take Any Medication After The Injection?

We generally recommend that you refrain from taking anti-inflammatory drugs after your PRP injection. However, a small percentage of people have a painful flare-up following their PRP injection (this includes swelling/pain/stiffness) for a few days. For this, we recommend a short course of anti-inflammatories. Don’t forget to take your usual chronic medications.

How Long Do They Last And Can I Have More?

The duration of relief varies from person to person. Our experience is that patients have about 6 to 12 months of relief. Patients who have good relief for many months may have repeated injections. Some have continued relief while in others repeat PRP therapy does not help.

What If PRP Doesn’t Help Me?

If all conservative measures, including PRP, fail to relieve your symptoms, then surgical options should be considered.

What Is The Cost Of PRP?

We are a cash practise and charge the following:
• Platelets 1 knee: R700 excl consultation fee (this may differ if you are a new patient or follow up)
• Platelets 2 knees: R1400 excl consultation fee (this may differ if you are a new patient or follow up)

We ask the laboratory (Ampath) to do platelet counts on your whole blood when they draw it initially, and on some of the spun down PRP that we inject into your knee (that our nursing sister sends to the lab). This allows us to compare the counts for quality and research purposes.


We will ask you before each appointment to please complete a questionnaire on your knee for our research on PRP. This enables us to ensure that PRP therapy is successful and of good quality. All your personal details will remain confidential in this process.


To see a video of PRP procedure, please visit
Patient info

We ensure that quality care is afforded to our patients even before formal consultation by taking necessary information about our patients, their lifestyle, and their current ailments.

Knee Specialists in Johannesburg

Prof. Ponky Firer, Dr. Brad Gelbart, and Dr. Matthew Street specialize in knee conditions of any type. Their approach is to improve your mobility and lessen your pain in the least invasive manner possible.

Privacy Policy | Knee surgeon, orthopaedic knee surgeon , knee injury johannesburg

© Linksfield Knee Clinic 2020 | Designed by Digital Strategist