Does PRP Work for Knee Arthritis? What Patients Should Know
By Mark L. Barba, MD in
Orthopedic Surgeon | Hip and Knee Reconstruction | Joint Preservation | Orthobiologics
Patients with hip and knee pain often want clear answers about what is causing their symptoms and what treatment options may help. In this message, I share practical, evidence-based information on arthritis, joint preservation, replacement surgery, and selected orthobiologic treatments to help patients make informed decisions about their care.
Does PRP Work for Knee Arthritis? What Patients Should Know
Knee arthritis is one of the most common causes of joint pain, particularly in adults over the age of 40 or 50. As cartilage in the knee gradually wears down, patients may begin to notice stiffness, swelling, and discomfort with everyday activities such as walking, climbing stairs, or standing after sitting for long periods.
Many patients today are interested in treatments that may help reduce pain while delaying or avoiding surgery. One treatment that receives a great deal of attention is platelet-rich plasma, commonly referred to as PRP. But does PRP actually work for knee arthritis? The answer is more nuanced than many headlines suggest.
What Is Knee Arthritis?
Knee arthritis, most commonly osteoarthritis, occurs when the cartilage that cushions the ends of the bones in the joint gradually breaks down. Healthy cartilage allows the knee to move smoothly and absorb stress. When that cartilage becomes thin or damaged, the joint may become inflamed and painful.
Common symptoms include:
- Pain with activity, especially walking or climbing stairs
- Swelling in the knee joint
- Stiffness after sitting or resting
- Decreased range of motion
- A grinding or catching sensation in the knee
Arthritis develops slowly over time and may be influenced by factors such as age, previous injury, genetics, body weight, and joint alignment.
What Is PRP?
Platelet-rich plasma (PRP) is a treatment that uses components of a patient’s own blood to potentially help support healing and reduce inflammation.
The process involves:
- Drawing a small amount of blood
- Processing it in a centrifuge to concentrate platelets
- Injecting the platelet-rich portion into the affected joint
Platelets contain growth factors and signaling proteins involved in the body’s natural healing processes. Concentrating these factors and delivering them to an inflamed area may help improve the environment inside the joint.
How PRP May Help Knee Arthritis
PRP is not considered a cure for arthritis and it does not reliably regenerate cartilage. However, in selected patients it may help in several ways.
First, PRP may help modulate inflammation inside the joint. Arthritis pain is often driven not only by cartilage loss but also by inflammatory changes in the joint lining.
Second, growth factors within PRP may influence cell signaling within the joint, potentially supporting healthier tissue function.
Finally, PRP may improve the overall joint environment, which can translate into improvements in pain and function for some patients.
Clinical studies suggest PRP injections may provide symptom improvement for certain patients with mild to moderate knee arthritis.
Who May Be a Good Candidate for PRP?
PRP tends to work best in patients who still have some remaining cartilage in the joint. Patients with early or moderate arthritis may be more likely to see benefit than those with advanced bone-on-bone disease.
Patients who may consider PRP include:
- Individuals with mild to moderate knee arthritis
- Patients who continue to have symptoms despite physical therapy or medications
- Patients looking for options that may help delay more invasive treatment
- Active individuals hoping to maintain activity levels
Not every patient is an ideal candidate, which is why a careful evaluation is important before considering this treatment.
How PRP Compares With Cortisone Injections
Many patients are familiar with cortisone injections, which are commonly used to reduce inflammation in arthritic joints.
Cortisone injections often provide rapid pain relief, but the effect may be temporary and sometimes lasts only a few weeks or months.
PRP works differently. Rather than suppressing inflammation immediately, PRP attempts to support the body’s own healing signaling processes. Because of this, PRP may take longer to show results, but improvements may last longer for some patients.
Both treatments can have a role depending on the individual situation.
When Should You See an Orthopedic Specialist?
Persistent knee pain should not simply be ignored, especially if symptoms are affecting daily activities or exercise.
An orthopedic evaluation may be helpful if you experience:
- Knee pain lasting more than several weeks
- Recurrent swelling in the joint
- Difficulty walking or climbing stairs
- Loss of motion in the knee
- Pain that interferes with normal activity
A specialist can help determine the underlying cause and discuss appropriate treatment options.
Closing Thoughts
PRP is one of several treatments that may help manage symptoms of knee arthritis in selected patients. While it does not reverse arthritis, it may help reduce inflammation and improve function for some individuals.
The key is identifying which patients are most likely to benefit and incorporating PRP into a broader treatment plan that may include strengthening, activity modification, and other therapies.
If you are dealing with persistent hip or knee pain and want to understand your treatment options, an evaluation with an orthopedic specialist can help determine the most appropriate next step.
