Platelet Rich Plasma in Osteoarthritis of the Knee

Osteoarthritis (OA) is a leading cause of severe long-term pain and disability affecting approximately 10% of the global population. Regenerative solutions and new tissue engineering based strategies are promising for treatment of moderate OA. 

Current research for treatment of knee OA with PRP is promising; however, there is a lack of consensus regarding the preparation of standardized dosing with an appropriate absolute number of platelets and concentration. Some studies report PRP preparations from between 20 to 100 ml of blood, with a concentration of 2-10 x106 platelets/µl.

A study by Bansal et al. demonstrated that a dose of 10 billion platelets in 8 ml volume of PRP improves functional outcomes and protects the articular cartilage from further wear and tear in patients with knee OA. 

Different scales like WOMAC (measure used in assessing pain, stiffness and function) improved significantly in the first month with PRP injection and also after the 3, 6 and 12 months follow up when compared to the control group. The study demonstrated no structural changes in the knee compared to cellular therapy (stem cells). However, they observed that PRP has a chondro-protective structural benefit in terms of a better maintenance of the joint space width and cartilage thickness. 

The study showed maintained effectiveness at one year after a single injection of PRP. Also, they evaluated the correlation of pro-inflammatory cytokines like IL-6 and TNF-α, which were decreased with subsequent clinical improvement in patient reported outcomes and that cytokine levels correlated with the degree of pain. 

As shown in this study, multiple others have demonstrated that the use of PRP for the treatment of osteoarthritis is an excellent alternative, with good results even when compared to other interventional treatments like steroid injections, with a prolonged effect and with the advantage of not having adverse effects.


Bansal, H., Leon, J., Pont, J.L. et al. Platelet-rich plasma (PRP) in osteoarthritis (OA) knee: Correct dose critical for long term clinical efficacy. Sci Rep 11, 3971 (2021).