Platelet-rich plasma (PRP) therapy is a treatment that uses your own blood to treat damaged tissues. It may help reduce pain from osteoarthritis, but more research is needed.

Injections of platelet-rich plasma (PRP) are a novel treatment for managing pain related to osteoarthritis of the knee.

Some PRP preparations have approval from the Food and Drug Administration (FDA), but approval does not yet cover the use of PRP in osteoarthritis of the knee. Nevertheless, some clinics may offer PRP “off-label.”

The American College of Rheumatology and the Arthritis Foundation (ACR/AF) recommend avoiding PRP because it hasn’t been fully developed and standardized. This means you cannot be sure of what your dose contains.

With further research, however, PRP may become a useful treatment option for osteoarthritis of the knee.

PRP therapy for osteoarthritis of the knee works by injecting platelet-rich blood into the area surrounding your knee to help reverse existing tissue damage.

Your blood is comprised of four components. Most of your blood is liquid, known as plasma. The other three components are platelets, white blood cells, and red blood cells.

Platelets play a key role in the clotting of your blood. They also contain growth factors that could help tissues repair themselves by causing new cells to form, according to the American Academy of Orthopaedic Surgeons (AAOS).

Some research suggests that PRP may be an effective treatment for knee osteoarthritis. For example:

  • A 2022 study of 153 participants found that after a 6-month follow-up, PRP helped improve symptoms of pain and stiffness, mobility and function, and quality of life.
  • A 2021 study of 118 participants found that after an average of 51.7-month follow-up, PRP helped improve symptoms of knee osteoarthritis.
  • A 2020 review found that after 3-, 6-, and 12-month follow-ups, PRP was a more effective treatment than steroids, hyaluronic acid, and placebos.
  • A 2017 review found that after 3-, 6-, and 12-month follow-ups, PRP helped reduce pain and improve physical function compared to placebos.

Despite the positive outlook, other studies have found conflicting results for using PRP as a treatment for knee osteoarthritis. For instance, a 2019 review noted that some studies support using PRP for knee osteoarthritis but others say it has no effect.

More studies are needed to determine whether PRP could offer a safe, effective, and sustainable treatment option for knee osteoarthritis.

The AAOS notes that PRP doesn’t pose additional risks compared with more conventional treatment options for knee osteoarthritis.

That said, an injection into the knee joint may entail some risks, including:

The 2017 review mentioned above found that some people also experienced:

It’s important to note that PRP may be an expensive treatment for knee osteoarthritis. In most cases, you’ll require multiple injections over a period of time, too.

Speak with a healthcare professional about the cost of PRP and the potential side effects. They could help determine whether it’s an appropriate treatment option for you.

PRP therapy is a three-step process:

  1. A doctor will draw a small amount of blood from your arm.
  2. They’ll put the blood sample into a centrifuge to separate the components and obtain a concentrated suspension of platelets in plasma.
  3. A doctor will numb your knee and inject the PRP into the joint space in the knee. They may use ultrasound to guide the injection.

After resting, you will be able to go home. You should arrange for someone to drive you home, as there may be pain and stiffness after the injection.

After the PRP procedure, a doctor may advise you to:

You may need crutches or an assistive device for a few days to keep the weight off your knee.

Follow your physician’s advice about follow-up appointments.

Does PRP work on arthritic knees?

Research suggests that PRP may be more beneficial than other treatment options for knee osteoarthritis. However, more research is needed to fully support its long-term benefits.

What is the success rate of PRP for knee arthritis?

A 2021 study found that PRP was successful 60% of the time. That said, multiple PRP injections are most likely needed over time to help manage knee osteoarthritis.

How long do PRP injections last in the knee?

There’s no consensus among research as to how long the effects of PRP injections last for knee osteoarthritis. A 2022 review found some studies report benefits from PRP therapy up to 12 months after the injection, but one study found no more benefits after 24 months.

Can PRP regenerate cartilage in the knee?

PRP may help improve symptoms associated with knee osteoarthritis. However, imaging tests haven’t found that it could regenerate cartilage, according to the AAOS.

Some evidence suggests that PRP therapy may help manage pain associated with osteoarthritis of the knee. However, more research is needed.

Experts don’t currently recommend PRP injections for osteoarthritis of the knee due to the lack of standardization at the preparation stage.

If you’re considering PRP, discuss it with a doctor and follow their advice. Remember, PRP is an experimental treatment that clinics can only provide off-label.