PRP vs Cortisone Shots for Knee Arthritis: Pros, Cons and When to Choose Each

Joint pain from knee arthritis or chronic tendon irritation can make simple daily tasks feel harder than they should. When searching for relief, most patients end up comparing two of the most common non-surgical injection options: PRP (platelet-rich plasma) and cortisone shots.

Both treatments are widely used, but they work very differently. Cortisone can reduce inflammation quickly, while PRP aims to support long-term healing. Understanding these differences helps you make a clear, confident choice about which option fits your goals, your timeline, and your condition.

This guide breaks down how each treatment works, what to expect, who each option is best for, and how to think through your next step.

What PRP and Cortisone Are Most Commonly Used For

Both injections are used for:

• Knee osteoarthritis

• Shoulder pain

• Hip joint pain

• Tendon issues like tennis elbow or Achilles irritation

• Bursitis or general joint inflammation

Quick Facts:

• Corticosteroid injections may offer short-term symptom relief for knee osteoarthritis.

• PRP shows variable results across studies, but many patients report longer-lasting relief compared to steroid injections.

Think of it this way:

• Cortisone helps calm the fire quickly.

• PRP helps support the rebuilding process over time.

To decide which is right for you, compare how they differ in onset, duration, safety, cost, and long-term goals.

What Are Cortisone and PRP Injections?

Cortisone (Steroid) Injection

A cortisone shot injects a powerful anti-inflammatory medication directly into the joint or soft tissue. This reduces swelling and pain quickly.

Key points:

• Fast-acting relief

• Often covered by insurance

• Not regenerative; does not repair tissue and has been shown to degenerate cartilage

• Relief tends to fade within weeks to a few months

PRP Injection (Platelet-Rich Plasma)

PRP uses your own blood, processed to create a highly concentrated solution of platelets and growth factors. These help stimulate tissue repair, reduce inflammation naturally, and improve long-term function.

Key points:

• Comes from your biology

• Designed to support tissue healing

• Slower onset but can last longer

• Usually not covered by insurance

PRP outcomes can vary depending on how the PRP is prepared and delivered, which is why image guidance and high-quality processing matter.

Common Areas Treated with PRP and Cortisone

Although both treatments are used across the body, these areas are the most common:

• Knee osteoarthritis (the most frequent comparison point)

• Shoulder rotator cuff or biceps tendon issues

• Elbow conditions like tennis elbow

• Hip or gluteal tendon pain

• Achilles or plantar fascia injuries

For knee arthritis, PRP is often chosen by patients who want a more regenerative approach, while cortisone is chosen for fast short-term relief.

Risks and Side Effects (PRP vs Cortisone)

Below is a clear comparison of what patients typically experience.

Side-by-Side Comparison Table

Frequency Limits

Cortisone shots are limited because repeated steroid exposure can weaken cartilage or tendons over time. Most providers limit to 3–4 injections per joint per year.

Recovery, Outcomes, and Timelines

PRP Recovery Timeline

• Days 0–3: Soreness is normal; avoid NSAIDs

• Days 3–7: Light mobility, start gentle movement

• Weeks 2–6: Gradual strengthening; tissue repair increases

• Weeks 6–12: Reassessment window for improvement

Cortisone Recovery Timeline

• 24–48 hours: Rest joint

• Days 2–5: Pain relief peaks

• Weeks 3–6: Relief gradually fades

Medication Do’s and Don’ts Around PRP

• Avoid NSAIDs (ibuprofen, naproxen) for several days before and after

• Acetaminophen is OK

• Discuss supplements that may thin blood or affect platelets

When to Choose PRP Over Cortisone Shots for Knee Arthritis

PRP is often a better fit if you:

• Have early to moderate knee osteoarthritis

• Want a treatment that supports tissue healing

• Had limited relief from cortisone in the past

• Are motivated to follow a rehab plan

• Prefer a more natural biologic treatment

Cortisone May Be The Better Fit If You:

• Need fast relief for an acute flare

• Need a covered option

• Understand the benefit is short-term

• Are not ready for a regenerative approach

Series vs Single Treatments

• PRP: often 2–3 injections spaced weeks apart

• Cortisone: single injections spaced months apart

Cost and Insurance Coverage

• PRP is usually self-pay, with costs varying by clinic, location, and number of injections needed.

• Cortisone is often covered by insurance for medically indicated arthritis or tendon issues.

Patients commonly choose PRP when long-term improvement is the goal and when they want to avoid repeated steroid exposure.

When to Call Your Provider

Contact your clinician if you notice:

• Increasing redness or swelling

• Fever or chills

• Severe or unrelenting pain

• Numbness or weakness

• Blood sugars rising unexpectedly after a steroid shot

These issues are uncommon, but it’s always better to check.

Clear Answers on Cortisone, PRP, Pain Relief & Safety

Question 1: How long do cortisone shots last in the knee?

Most people experience relief for several weeks to a few months, strongest during the first 4–6 weeks.

Question 2: How many steroid shots can I get in a year?

Most clinicians limit to 3–4 per joint per year.

Question 3: How many PRP injections will I need?

Many knee arthritis plans use 2–3 injections, followed by a reassessment.

Question 4: Can I take ibuprofen after PRP?

Avoid NSAIDs after PRP because they may interfere with platelet activity. Acetaminophen is OK.

Question 5: Is PRP covered by insurance?

Most insurance plans do not cover PRP. It is typically a self-pay service.

Question 6: Can PRP delay knee replacement?

For early to moderate OA, PRP may help delay surgery by improving function and reducing pain in some patients.

IOW Expert Insight and Next Steps

Interventional Orthopedics of Washington takes a diagnostic-first approach, using image-guided injections and individualized treatment plans to help patients choose the right solution based on their joint health, activity level, and goals. Whether you’re weighing cortisone or considering PRP for longer-term improvement, a focused evaluation helps determine what will give you the safest and most effective outcome.

Ready to find out which treatment fits your condition? Schedule a consultation with the team to review your imaging, history, and next steps.