PRP for arthritic knees: a science update [4m]

I have long been critical of platelet-rich plasma (PRP) — injections of your own concentrated blood, still supposedly “ regenerative ” despite piles of underwhelming evidence. In July I posted about an interesting new trial that was, predictably, “ a credible negative for PRP .” As always, “ negativity ” about PRP is a complaint magnet. Usually it’s just “ it worked for me ,” but sometimes I get…