Why Different Types of PRP are Used for Joints and Tendons
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.
Why Different Types of PRP Are Used for Joints and Tendons
Many patients are surprised to learn that not all platelet-rich plasma (PRP) preparations are the same. In particular, physicians often distinguish between two common types:
- Leukocyte-poor PRP (LP-PRP)
- Leukocyte-rich PRP (LR-PRP)
The main difference between these preparations is the amount of white blood cells (leukocytes) present in the final injection. These cells can influence inflammation, which is why different PRP formulations may be more appropriate for different tissues.
Understanding this distinction helps explain why one type of PRP may be preferred for joint conditions, while another may be useful for tendon injuries.
What Role Do Leukocytes Play?
Leukocytes are part of the body’s immune system and are involved in inflammatory responses. When tissues are injured, white blood cells release signals that help initiate healing.
However, inflammation can be a double-edged sword. In some tissues, controlled inflammation may help stimulate repair. In others, excess inflammation may worsen pain or contribute to tissue breakdown.
Because of this, physicians often consider how inflammatory a tissue environment should be when selecting the type of PRP to use.
Why Leukocyte-Poor PRP Is Often Used for Joints
In joints affected by arthritis, the environment is frequently already inflamed. The joint lining, known as the synovium, may produce inflammatory chemicals that contribute to pain and cartilage breakdown.
For this reason, many physicians prefer leukocyte-poor PRP when treating joint conditions such as knee arthritis.
LP-PRP focuses on delivering platelets and growth factors while minimizing additional inflammatory cells. The goal is to help support a healthier joint environment without significantly increasing inflammation.
Why Leukocyte-Rich PRP May Be Used for Tendons
Tendon injuries often involve a different biologic situation. Many chronic tendon problems, such as tendinopathy, are not purely inflammatory conditions but instead represent degenerative changes within the tendon tissue.
In these cases, a controlled inflammatory stimulus may actually help restart a healing response.
Leukocyte-rich PRP contains a higher concentration of white blood cells, which may help stimulate this process. For certain tendon conditions—such as patellar tendinopathy or tennis elbow—this additional inflammatory signaling may be beneficial.
Matching the Treatment to the Tissue
One of the evolving ideas in orthobiologic medicine is that the biologic environment of each tissue matters.
Different tissues respond differently to inflammatory signals, growth factors, and cellular components.
Because of this, physicians increasingly tailor PRP preparations to the specific condition being treated. Factors that may be considered include:
- The type of tissue involved
- The degree of existing inflammation
- The stage of injury or degeneration
- The overall treatment goals
This individualized approach reflects a growing understanding that orthobiologic therapies are not one-size-fits-all treatments.
Other Factors That Influence PRP Treatments
In addition to leukocyte content, several other variables may influence PRP preparations, including:
- Total platelet dose
- Injection volume
- Cellular composition
- Preparation technique
These factors are areas of ongoing research as physicians work to better understand how orthobiologic treatments can be optimized.
Closing Thoughts
PRP therapy continues to evolve as researchers learn more about how biologic signals influence tissue healing. One important concept is that different PRP formulations may serve different purposes depending on the tissue being treated.
Leukocyte-poor PRP is often used in joints where minimizing inflammation may be beneficial, while leukocyte-rich PRP may be helpful in certain tendon conditions where a healing response needs to be stimulated.
As with any medical treatment, careful evaluation and individualized care remain essential.
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.
