PRP vs Cortisone Injections: Which Helps Knee Pain?
Two of the most common injection options for knee pain work in completely different ways. Cortisone dials down inflammation fast. PRP asks your body to repair the damaged tissue. Choosing between them depends on what's actually wrong with your knee, how long you've had the problem, and what you're hoping to get back to doing.
What Cortisone Actually Does
A corticosteroid injection delivers a synthetic steroid directly into the knee joint. It reduces inflammation quickly, often within a few days. For a lot of patients, that means real pain relief that lets them move again, sleep through the night, or get through a workday.
The catch is that cortisone doesn't fix anything. It manages the symptom. Once the anti-inflammatory effect fades, which can take weeks or months, the pain frequently returns. Repeated cortisone injections over time can also break down cartilage, so most doctors limit how often they give them.
Cortisone works best when inflammation is the main problem. An acute flare of knee arthritis, bursitis, or a joint that's swollen and hot responds well. It's also useful as a short-term bridge while a patient works through physical therapy or prepares for another treatment.
What PRP Actually Does
Platelet-rich plasma comes from your own blood. A small sample gets drawn, spun in a centrifuge to concentrate the platelets, and then injected into the injured area. Platelets carry growth factors that signal tissue to repair itself.
PRP doesn't suppress inflammation the way cortisone does. Instead, it nudges the body toward healing. That process takes time. Most patients don't feel significant improvement for four to eight weeks after the injection. Some need more than one treatment.
The research on PRP has grown steadily. Studies show it works particularly well for knee osteoarthritis, tendon injuries, and soft tissue damage where the goal is actual tissue improvement rather than temporary relief. high-dose PRP treatment uses a higher platelet concentration than standard PRP, and some patients with more advanced joint damage benefit from that increased dose.
Head-to-Head: What the Research Shows
Several well-designed studies have compared the two directly for knee osteoarthritis. The consistent finding is that cortisone provides faster early relief but PRP produces better results at the six-month and twelve-month marks. Patients who received PRP reported less pain and better function over the long term.
That doesn't make cortisone the wrong choice. It makes it a different choice, for a different goal. If you need to get through a wedding next weekend, cortisone makes sense. If you want your knee to feel better next year, PRP is worth the wait.
For patients dealing with bone on bone arthritis, neither injection is a cure. But PRP can slow the progression and improve quality of life in ways cortisone doesn't.
Who Is a Good Candidate for Each
Cortisone tends to be the right call when:
- The knee is actively inflamed and swollen
- You need fast relief for a specific event or obligation
- You're in the early stages of arthritis
- You're using it alongside physical therapy to make movement tolerable
PRP tends to be the right call when:
- You've already tried cortisone and the relief didn't last
- You have a chronic condition like knee osteoarthritis or a tendon injury
- You want to avoid surgery and are willing to be patient with the recovery timeline
- Your doctor has confirmed there's still enough tissue present to respond to regenerative treatment
Imaging matters here. A doctor looking at your MRI or X-ray can tell you whether the damage in your knee is likely to respond to PRP or whether the joint has deteriorated past the point where regenerative therapy gives you a realistic benefit.
Other Options Worth Knowing About
PRP and cortisone aren't the only injections used for knee pain. Hyaluronic acid injections add lubrication to the joint and work well for some patients with mild to moderate arthritis. Bone marrow aspirate concentrate (BMAC) injection uses stem cells from your own bone marrow and is an option for more significant joint damage. Alpha-2-Macroglobulin (A2M) injection targets a protein that breaks down cartilage, so blocking it slows joint deterioration.
The right treatment depends on your specific diagnosis. knee arthritis treatment isn't a single path. A good orthopaedic evaluation looks at your imaging, your symptoms, your activity level, and your goals before recommending anything.
What to Expect After Each Injection
After cortisone, most patients feel better within three to five days. There's sometimes a short flare in the first day or two where the joint feels worse before it improves. That's normal.
After PRP, expect some soreness at the injection site for several days. Avoid anti-inflammatory medications during this window because they interfere with the healing response you're trying to trigger. Activity restrictions vary by patient, but most people return to light movement within a week and see gradual improvement over the following two months.
Neither injection is a one-and-done answer for everyone. Your doctor should be tracking your response and adjusting the plan if you're not improving the way you'd expect.
If you're weighing these options for knee pain in Huntingdon Valley, getting a clear diagnosis first makes all the difference. At Iron Mountain Orthopaedic Institute, Dr. Ayzenberg reviews your imaging and history before recommending any injection, so you're not guessing at a solution. Schedule a consultation to get a straight answer about what your knee actually needs.