Purpose

To compare the clinical outcomes of osteoarthritis indices (WOMAC and Lequesne scores) and adverse events in the treatment of osteoarthritis (OA) of the knee with platelet-rich plasma (PRP) versus hyaluronic acid (HA) or placebo.

Methods

A systematic review and meta-regression were performed to compare outcomes between PRP injections versus HA or placebo. Relevant randomized control trials were identified from Medline and Scopus from date of inception to 13 August 2015.

Results

Nine of 551 studies were eligible; 6, 5, 5, 5, 2, 2, 2 and 7 studies were included in pooling of WOMAC total, pain, stiffness and function scores, Lequesne score, IKDC score, EQ-VAS score and adverse events in OA knee patients, respectively. The PRP injections had -15.4 (95 % CI -28.6, -2.3, p = 0.021), lower mean WOMAC total scores, and 8.83 (95 % CI 5.88, 11.78, p < 0.001), 7.37 (95 % CI 4.33, 10.05, p = 0.021) higher mean IKDC and EQ-VAS scores when compared to HA injections. However, PRP injections had no significant differences in WOMAC pain, stiffness and function scores, as well as Lequesne score and adverse events when compared to HA or placebo.

Conclusion

In short-term outcomes (≤1 year), PRP injection has improved functional outcomes (WOMAC total scores, IKDC score and EQ-VAS) when compared to HA and placebo, but has no statistically significant difference in adverse events when compared to HA and placebo. This study suggests that PRP injection is more efficacious than HA injection and placebo in reducing symptoms and improving function and quality of life. It has the potential to be the treatment of choice in patients with mild-to-moderate OA of the knee who have not responded to conventional treatment.

Level of evidence

I.