What is the post-injection protocol after an intraarticular Platelet-Rich Plasma (PRP) knee injection?

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Post-Injection Protocol After Intraarticular PRP Knee Injection

After an intraarticular PRP knee injection, patients should follow a limited activity protocol for 24-48 hours followed by a gradual return to normal activities and implementation of a structured rehabilitation program to maximize therapeutic benefits. 1, 2

Immediate Post-Injection Protocol (First 24-48 Hours)

  • Restrict strenuous activities and avoid weight-bearing exercise for 24-48 hours to allow the platelets to adhere to the tissue and begin releasing growth factors 2
  • Apply ice to the injection site for 15-20 minutes every 2-3 hours if experiencing post-injection pain or swelling 1
  • Avoid use of NSAIDs for at least 7 days post-injection as they may interfere with the inflammatory cascade necessary for PRP effectiveness 2
  • Mild analgesics such as acetaminophen may be used if needed for post-injection discomfort 2

Short-Term Protocol (Days 3-14)

  • Gradually return to normal daily activities while avoiding high-impact activities 3
  • Begin gentle range of motion exercises to prevent stiffness and maintain joint mobility 4
  • Light walking is encouraged to promote circulation and healing 2
  • Continue to avoid NSAIDs during this period 2

Medium-Term Protocol (Weeks 2-6)

  • Implement a progressive exercise program focusing on:
    • Range of motion exercises 4
    • Muscle strengthening, particularly quadriceps and hamstrings 2
    • Low-impact aerobic activities such as stationary cycling or swimming 3
  • Gradually increase activity level based on symptoms 5
  • Consider physical therapy to optimize outcomes 2

Long-Term Protocol (Beyond 6 Weeks)

  • Continue with progressive strengthening and conditioning exercises 2
  • Return to normal activities as tolerated, with gradual reintroduction of higher-impact activities 3
  • Monitor symptoms and adjust activity levels accordingly 5

Important Considerations

  • The American Academy of Orthopaedic Surgeons (AAOS) notes that PRP may reduce pain and improve function in patients with symptomatic osteoarthritis of the knee, though evidence is limited 6
  • Multiple studies show that the maximum therapeutic effect of PRP typically occurs between 1-3 months post-injection 5, 3
  • Some protocols involve multiple injections (2-3) at monthly intervals for optimal results 3
  • Patients should be informed that results may vary, with some studies showing inconsistent outcomes, particularly in severe knee osteoarthritis 1, 2

Common Pitfalls to Avoid

  • Using NSAIDs too soon after injection, which may inhibit the inflammatory response necessary for PRP effectiveness 2
  • Returning to high-impact activities too quickly, which may compromise treatment outcomes 3
  • Expecting immediate results, as the therapeutic effects of PRP typically develop gradually over several weeks 5
  • Neglecting the importance of a structured rehabilitation program, which is essential for optimizing outcomes 2, 4

References

Guideline

Platelet-Rich Plasma Therapy for Knee Pain: Guideline Recommendations and Medicare Coverage

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Platelet-Rich Plasma Therapy in Orthopedic Conditions

Praxis Medical Insights: Practical Summaries of Clinical Guidelines, 2025

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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