Knee Injections

The effects seem to differ widely for patients. Some notice pain and function improvement within days, others take several weeks, and some people receive no benefit at all. Those who do get pain relief usually report it lasting from twelve - forteen months, after which re-injection is an option. 

Some people may notice a reaction close to the injection site, such as pain, redness, warmth, slight swelling or stiffness, immediately after the injection. These symptoms generally do not last longer than 48 hours. We recommend applying an ice pack to the knee and taking some simple pain relief to ease the discomfort.

Occasionally, people report a headache, muscle pain, nausea, sore throat and flu-like symptoms. If these occur and do not resolve within 24 hours, we recommend you consult your doctor.

There are some rare side effects that are more serious, and if experienced you should contact your doctor immediately. They include:

• allergy – rashes, hives, itching, flushing and swelling of the face, tongue or throat, chest tightness and shortness of breath
• severe inflammation of the joint, a large increase in pain and swelling in your knee, or your knee becomes red and hot. These signs may indicate an infection in the joint, which can be serious, especially if left untreated.

The injection process itself only lasts a few minutes.

Wear shorts, or bring some with you to get changed into.

Generally, joint injections are more painful than normal muscular injections. The injection will cause some pain as it is given. However, while it differs from person to person, most patients tolerate it well.

Yes, local anaesthetic is used for these injections.

Yes, please bring the most recent version of your MRI or X-Ray. 

Yes, you can drive immediately after your injection.

You may return to work and your normal day-to-day activities immediately after the injection.

You should refrain from heavy lifting and strenuous activities for 24–48 hours or until symptoms from the injection have subsided.

You may experience soreness and ache for 24–72 hours.

Simple pain relief such as Panadol or Panadeine along with icing the knee regularly for 48 hours is all that is generally required.

Yes, you may take your normal anti-inflammatories.

Autologous Concentrated Plasma (ACP, or Platelet-Rich Plasma (PRP)) is derived from your own blood. Both processes involves spinning or centrifuging the blood until it separates into layers.

‘Plasma’ is the liquid component of blood, being mostly water, but it also includes proteins, nutrients, glucose, and antibodies, among other components.

Platelets are a natural part of the blood that help it clot when an injury occurs; a person with defective platelets or too few platelets will bleed excessively. However, platelets, when ‘activated’, can also secrete substances called growth factors and other proteins that regulate cell division, stimulate tissue regeneration, and promote healing. It is these substances that are of interest in PRP treatments.

White blood cells (WBC), or leukocytes, are your immune system cells. They protect your body against disease and foreign invaders.

Red blood cells (RBC), or erythrocytes, are the most common blood cell and are principally vehicles for transporting oxygen around your body.

When blood is centrifuged, it separates into three layers: Plasma, the “buffy coat”, and the red cell pack.

Platelet Rich Plasma (PRP) systems harvest the entire ‘buffy coat’, which is the thin central layer that contains most of the platelets, white blood cells and usually some red blood cells as well.

The Autologous Conditioned Plasma (ACP) system is designed to harvest only the top portion of the buffy coat with the younger, lighter platelets, but very few red or white blood cells which are heavier and lower down.  Scientific research has found that the presence of red and white blood cells can retard any healing response and reduce anti-inflammatory effects.

The theory behind injecting ACP into the arthritic knee is that the cocktail of growth factors, proteins and other substances delivered will:

• Reduce pain by altering the way the pain receptors are functioning
• Inhibit inflammation
• Stimulate a healing response and slow down the progression of osteoarthritis
• Increase the production of natural lubricating fluid in the joint

A major review of multiple studies of low- to high-quality evidence found that platelet-rich injections improved pain and function as early as two-months after treatment. Improvement peaked at six months, with symptomatic relief for up to twelve months. These authors concluded that those with early osteoarthritic changes in the knee should consider these injections as a treatment option. These studies also show, however, that the injections are not effective for everyone. There is no scientific evidence suggesting that the articular cartilage is in any way repaired, or that the rate of arthritic deterioration of the joint is slowed.

Because your own blood is used, there is no risk of transmissible disease or reaction to a foreign body.

There is always the risk of infection with any joint injection. We use best-practice sterile technique, and in our experience, the risk is less than 1 in 1000. If an infection does occur, it can usually be successfully treated.

Local anaesthetic is not used for the injection as it has been shown to be harmful to joint cartilage. Patients may experience discomfort for approximately 24 hours after the injection. Simple analgesia such as Panadol and the use of ice can help alleviate these symptoms.

Anti-inflammatory medications should be avoided for 48 hours after the injection so as not to inhibit any healing cascade put into effect by the ACP or PRP. You may return to work and other normal activities immediately after treatment, but should refrain from strenuous activity for a few days.

Most patients require three injections, each approximately two weeks apart, in order to achieve the desired results.
Some patients report that they feel a significant improvement after the first injection, and so don’t proceed to a second.
Most people feel that the injections are effective in relieving the pain and inflammation, but a minority have reported no or minimal improvement.

ACP Procedure 
The ACP procedure begins with a small amount of blood (15ml) being taken from a vein in your arm into a sterile double syringe system.
The double syringe is then placed in a centrifuge and spun at 1500rpm for nine minutes.
The spinning separates the blood components, and the platelets and the plasma are drawn into the second, smaller sterile syringe, leaving the red and white blood cells behind.
The final solution is injected into your knee joint.
You will require 3 x injections two weeks apart for the full efficacy of the injection. 

ACP MAX Procedure 
The ACP Max™ procedure involves taking 3 x syringes of (30ml) from a vein in your arm into a sterile double syringe system. 

The ACP procedure will take about 25 minutes. The injection itself only lasts a few seconds.
The ACP MAX procedure will take about 40 minutes. The injection itself only lasts a few seconds.

Wear shorts, or bring some with you to get changed into.

Generally, joint injections are more painful than normal muscular injections. The injection will cause some pain as it is given. However, while it differs from person to person, most patients tolerate it well.

No, unfortunately, local anaesthetic interferes with the effectiveness of the injection so in general we don’t use it.

Yes, please bring the most recent version of your MRI or X-Ray. 

Yes, you can drive immediately after your injection.

You may return to work and your normal day-to-day activities immediately after the injection.

You should refrain from heavy lifting and strenuous activities for 24–48 hours or until symptoms from the injection have subsided.

You may experience soreness and ache for 24–72 hours.

Simple pain relief such as Panadol or Panadeine along with icing the knee regularly for 48 hours is all that is generally required.

Anti-inflammatories should be avoided for the first 48 hours after the injection to not inhibit any healing processes put into effect by the ACP treatment.

The result is different for each person. For some, it is a week after the first injection; for others, it is six weeks after the third injection. About 20% of patients report little or no improvement at all.