Platelet-Rich Plasma in Tendon and Joint Injury: Preparation Heterogeneity as the Unacknowledged Confounder
DOI:
https://doi.org/10.5281/zenodo.22548391Keywords:
Platelet-rich plasma, Leukocyte concentration, Tendinopathy, Knee osteoarthritis, Classification systems, Reporting standardsAbstract
Platelet-rich plasma (PRP) is routinely discussed in the sports-medicine literature as if it were a single,
well-defined intervention, yet commercial and laboratory preparation systems vary several-fold in the
platelet concentration factor they deliver and range from strongly leukocyte-poor to strongly
leukocyte-rich formulations. This preparation heterogeneity is rarely reported in enough detail to
reproduce, and it appears to interact with the target tissue: leukocyte-rich preparations trend favourable
in chronic tendinopathy while leukocyte-poor preparations trend favourable for intra-articular use in
knee osteoarthritis, a pattern obscured whenever trials and meta-analyses pool 'PRP' as one category.
This review synthesises the classification systems proposed to standardise PRP reporting, the evidence
that composition varies by preparation method, and what that variability means for interpreting the
tendon and joint trial literature.
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