Dear Editor

I read the article by Martinelli et al. [1] in which they reported promising results with the use of platelet-rich plasma injections for treating muscle and tendon injuries and degeneration [2, 3]. The authors presented their study well. I congratulate them for opening new horizons on chronic plantar fasciitis with use of PRP and providing initial clinical assessment of its effectiveness. I have a query about the article, however.

The author mentioned the amount of blood withdrawn, centrifugation rate, and anticoagulant, but did not mention whether leukocytes were separated prior to injection or whether whole PRP with leukocytes was injected. Few studies report separating leukocytes from PRP; those few studies have reported separating leukocytes for treating osteoarthritis of the knee to prevent early inflammatory processes [4]. If leukocytes were not separated in this study, then after separating them and then injecting PRP, much better results may be achieved.