PRP Injections for Knee Pain: What to Know First

What platelet-rich plasma actually is

PRP starts with a simple blood draw from your own arm. That sample goes into a centrifuge, which spins it at high speed and separates it into layers. One of those layers is unusually rich in platelets: the small cells your body sends to injury sites first. Platelets carry growth factors, the signaling proteins that recruit repair cells and coordinate healing.

A PRP injection concentrates that platelet-rich layer and places it directly into the irritated tissue. The idea is simple: deliver a strong dose of your body's own repair signals exactly where healing has stalled. Because the material comes from you, there is no donor tissue and no synthetic drug in the injection itself, which is part of why many patients find the concept appealing.

Why ultrasound guidance matters

A PRP injection is only as good as its placement. The knee is a crowded neighborhood: joint capsule, menisci, tendons, bursae, and fat pads all sit within a few centimeters of each other. An injection placed by feel alone can miss the target tissue entirely.

That is why we use ultrasound guidance. Real-time imaging lets us watch the needle travel to the intended structure and confirm the PRP is delivered where it is supposed to go, whether that is inside the joint space or along an irritated tendon. Guided placement also tends to make the procedure more comfortable, because it avoids unnecessary probing.

The knee problems patients consider PRP for

Most of the patients who ask us about PRP fall into two groups:

• Osteoarthritis-related knee pain. When cartilage wears and the joint becomes achy, stiff, and swollen with activity, PRP is one of the non-surgical options patients weigh, often alongside exercise therapy and activity changes. Some research suggests PRP can reduce arthritis-related pain for a period of time in some patients, though study results are mixed and it does not regrow lost cartilage.
• Tendon irritation around the knee. Chronic patellar tendon pain and similar overuse problems are the other common reason. Tendons heal slowly because of limited blood supply, and PRP is one way to try to stimulate a stalled repair process.

If your pain traces back to how your whole lower body carries load, the knee is often the victim rather than the culprit. That is why we look at the entire chain, from the feet to the hips and spine, before recommending any injection for knee pain.

Realistic expectations and a realistic timeline

Here is the candid part. PRP is not a miracle shot, and any clinic that promises one is not being straight with you. It is a biological treatment, which means it works on the body's timeline, not the calendar you might prefer.

Expect the knee to feel sore for a few days after the injection; that early inflammation is part of the intended response. Meaningful improvement, when it comes, usually develops gradually over 4–12 weeks as tissue responds to the growth-factor signal. Some patients do well. Some improve modestly. Some do not respond at all. Results vary from person to person, and no honest provider can tell you in advance which group you will be in. What we can do is examine you carefully, tell you whether your particular knee problem is the kind PRP has a reasonable chance of helping, and say so plainly if it is not.

PRP is also not right for everyone. Active infection, certain blood disorders, some medications, and severe end-stage joint changes can all take it off the table. Advanced arthritis that truly needs a surgical consult deserves a referral, not an injection.

What the visit itself looks like

The procedure is simpler than most patients expect. The whole appointment usually takes under an hour. We draw a small amount of blood from your arm, exactly like a routine lab draw, and prepare it in the centrifuge while you relax. The skin over the knee is cleaned and numbed, and the injection itself takes only a few minutes under ultrasound guidance. You walk out of the office on your own.

For the first several days, plan on taking it easy: no hard workouts, and we generally ask you to avoid anti-inflammatory medications like ibuprofen around the procedure, because the inflammation PRP creates is the mechanism doing the work. We will give you a simple written plan for activity, icing alternatives, and when to resume normal exercise, and we check in on your progress at follow-up visits.

What it costs

Insurance rarely covers PRP, so we keep the pricing simple and public: $700 for one knee, $900 for both knees treated at the same visit, cash price. That includes the blood draw, the preparation, and the ultrasound-guided injection. There are no surprise facility fees, and you will know the complete cost before anything is scheduled.

How PRP fits alongside chiropractic care

At SpinalWorks Chiropractic in Moon Valley, North Phoenix, PRP is never a stand-alone product. A knee that hurts is usually a knee that is being loaded badly, and an injection cannot fix mechanics. Pairing PRP with a plan that addresses alignment, gait, hip and pelvic function, and the strength of the muscles that protect the joint gives the treated tissue its best chance, and helps keep the problem from simply returning.

If your knees are limiting your walks, your workouts, or your time chasing grandkids around the yard, start with a conversation. Schedule a consultation and we will help you figure out, honestly, whether PRP belongs in your plan.