PRP Injection for the Knee: Who It May Help, Recovery, Cost and Risks

What is a PRP injection for the knee?

A PRP injection for the knee is a shot of platelet-rich plasma made from your own blood and placed into the knee joint. A small sample of blood is spun in a centrifuge, which separates the platelets and plasma from the red blood cells. The concentrated platelets are then injected into the knee.

Platelets carry growth factors and other proteins involved in the body's normal healing process. The idea behind PRP treatment is to deliver a higher concentration of these proteins to the painful area. Because it comes from your own blood, allergic reactions are unlikely.

What is PRFM, and how is it different from PRP?

PRFM, or platelet-rich fibrin matrix, is also made from your own blood. At The Pur Health it is prepared with the Selphyl system, which is FDA cleared for preparing it. The fibrin forms a soft gel that holds the platelets in place, so they stay where they are injected longer than standard PRP. Dr. Munib explains which one fits your knee or tendon.

Does PRP help bad knees?

PRP may ease pain and improve function for some people with knee osteoarthritis, but the evidence is mixed and benefits, when they happen, may last several months. Some people report less knee pain for several months. Others notice little change.

• The American Academy of Orthopaedic Surgeons gives PRP a limited-strength recommendation for knee osteoarthritis, meaning it may reduce pain and improve function, but the support is not strong.
• Other specialist groups do not recommend it, or say there is not enough evidence to decide.
• PRP has not been shown to regrow cartilage or reverse arthritis. Any benefit is in pain and function.

That is why Dr. Munib talks through what PRP can and cannot do before you decide. You are paying for a reasonable chance of benefit, not a promise.

Who may be a candidate for PRP knee injections?

PRP is most often considered for mild to moderate knee osteoarthritis that has not settled with simpler care. Typical candidates include:

• Adults with pain from early to moderate arthritis, confirmed by exam and often an X-ray
• Active people who want to stay moving and are not ready for, or do not need, surgery
• People whose pain continues despite exercise, physical therapy, weight management and simple pain relief
• People who want to avoid repeated steroid injections

Can PRP work at 50 or 60? Age alone does not rule it out. Many people asking about PRP for knee pain are in their 50s and 60s. What matters more is how advanced the arthritis is.

Can PRP treat knee tendon pain and injuries?

Platelet injections are also used for some long-running tendon problems, such as patellar tendon pain below the kneecap. For knee injuries like a meniscus tear or a torn anterior cruciate ligament (ACL), evidence is even more limited, and a structural tear often needs an orthopedic surgeon's opinion first.

Read about PRFM tendon injections at The Pur Health

Who should not have PRP in the knee?

• Severe, bone-on-bone arthritis, where injections are unlikely to do much
• An infection in the joint or the skin over it
• Low platelets or certain blood disorders
• Some blood-thinning medications, which need review first
• A joint that locks or gives way, which needs a different workup first

What should you do before a PRP injection?

• Tell Dr. Munib about every medicine and supplement you take, especially blood thinners and anti-inflammatory pain relievers such as ibuprofen or naproxen. She will tell you which ones to pause and for how long.
• Drink water and eat a normal meal beforehand, since a blood draw is part of the visit.
• Bring any recent knee X-rays or MRI reports.
• Plan a lighter day afterward.

PRP injection procedure: what happens during the visit?

A PRP knee procedure takes about 45 minutes to an hour, and you go home the same day. The steps:

1. 1.Dr. Munib examines the knee and reviews your history and imaging.
2. 2.A small amount of blood is drawn from your arm, much like a routine blood test.
3. 3.The blood is spun in a centrifuge to concentrate the platelets.
4. 4.The skin over the knee is cleaned and may be numbed.
5. 5.The PRP is injected into the joint. Some clinicians use ultrasound guidance to place the needle.
6. 6.You rest briefly and go home the same day.

Most people describe pressure or fullness in the joint during the shot, which settles over the next few days.

What is PRP injection knee recovery time?

Most people return to normal daily activities within a day or two of a PRP knee shot, though the joint may feel sore or swollen for several days, and sometimes for a week or two. Worse pain in the first days is common and does not mean the treatment has failed.

• Walking: you can usually walk out of the office and move around normally the same day.
• First few days: rest the knee, use ice for comfort and avoid heavy exercise.
• Pain relief: acetaminophen is usually fine. Ask before using anti-inflammatory pain relievers, since you may be asked to avoid them for a period.
• Exercise: light activity returns first. Running, jumping and heavy leg workouts usually wait a week or more, guided by how the knee feels.
• Results: any benefit tends to build slowly over several weeks, not right away.

Some people feel tired for a day afterward. Rest, fluids and a normal meal usually take care of it.

How many PRP injections are needed for the knee?

Some people need one PRP shot, and others do better with a short series spaced several weeks apart. There is no single agreed schedule. Dr. Munib decides with you based on your knee, your arthritis and how you respond. Do you have to do PRP forever? No. If it helps, the effect may last for months, and some people repeat it later when pain returns. If it does not help, there is no reason to keep going.

PRP vs cortisone vs hyaluronic acid: how do they compare?

Cortisone, hyaluronic acid and PRP are the three shots most often discussed for knee arthritis, and they do different jobs. None of them cures arthritis.

• Cortisone (steroid) shot: works quickly to calm a painful flare, often within days. The relief usually wears off within weeks to months, and repeated shots are generally limited.
• Hyaluronic acid (gel) shot: adds a lubricating fluid to the joint. Results are mixed, and orthopedic guidelines do not recommend it for routine use.
• PRP: made from your own blood, slower to work and with mixed results. When it helps, the benefit may last longer than a steroid shot.

Whatever the injection, the base of knee arthritis care stays the same: a regular exercise program with strength work for the thigh and hip, weight loss if you carry extra weight, physical therapy and, for some knees, a brace.

See joint pain care at The Pur Health

Does insurance cover PRP injections for the knee?

PRP for the knee is usually not covered by insurance. Most plans, including Medicare, do not cover PRP for joint pain, so PRP and PRFM treatments are self-pay. HSA and FSA cards are accepted. At The Pur Health, the price is shown in the booking window before you book, so you know the cost before treatment.

What are the risks and side effects of PRP?

PRP is generally low risk because it uses your own blood, and most side effects settle within a few days. Possible side effects include:

• Pain, soreness or swelling at the injection site for a few days
• Bruising where the blood was drawn or where the needle entered the knee
• Infection, which is rare when sterile technique is used
• Bleeding, or injury to a nerve or blood vessel, which is uncommon
• No improvement in pain

Call the office or seek care right away if the knee becomes hot, red and increasingly swollen, or if you develop a fever after the injection. These can be signs of infection.

How Dr. Munib approaches PRP for knee pain

Dr. Munib performs PRP and PRFM joint and tendon injections at The Pur Health in Irvine. A first visit may include an exam of the knee, a review of your imaging, your activity goals and your medications. From there, she may discuss whether PRP, PRFM, a steroid injection, physical therapy or weight management fits your knee best, and when a referral to an orthopedic surgeon makes more sense.

Referral is worth discussing when pain limits walking, sleep or daily life despite several months of treatment, when X-rays show severe arthritis, or when the knee locks or gives way.

Learn about PRP joint injections at The Pur Health

Book a visit in Irvine

If knee pain is keeping you from the things you enjoy, a visit is the place to start. The Pur Health is in-network with most PPO plans for office visits. Cash visits are $190 for new patients and $150 for returning patients. We are at 114 Pacifica, Suite 280, Irvine, CA 92618, and you can call (949) 647-5234.