Platelet-Rich Plasma (PRP) in Ligament and Tendon Repair

Abstract

Platelet concentrates such as platelet-rich plasma (PRP) have gained considerable popularity in regenerative medicine. In orthopedic surgery they are of special interest in the management of tissues that heal only slowly or not at all. Tendons and ligaments, for example the rotator cuff of the shoulder and the anterior cruciate ligament (ACL) of the knee, are prime candidates. Our research has focused on the effect of PRP on ACL healing as an alternative to ACL reconstruction with a graft after injury. In this chapter we will explain in detail what we have come to know about PRP production, about PRP constituents, and about the use of PRP in tendon and ligament repair with a special focus on the ACL. Briefly, we recommend the use of a 3X or lower platelet concentration within the PRP and suggest allowing for leukocyte and maybe even erythrocyte “contamination”, owing to the microbicidal effect and plentiful growth-factor release of leukocytes and the stimulation of collagen production by erythrocytes. Most importantly, we suggest that each clinical application should have a PRP preparation tailored for it. Finally, in the light of the added benefit of cell types other than platelets we encourage researchers and commercial providers of PRP machines to describe the cell mix of the employed platelet concentrates as exactly as possible.