title: Use of platelet-rich plasma to enhance tendon function and cellularity.
abstract: Clinical studies have shown inconsistent healing with subjective improvement after use of platelet-rich plasma (PRP) for tendinosis and partial tendon tears. We conducted a study to assess changes after injecting PRP into an intact rabbit patellar tendon (PT) model. In the study group (n = 10), an incision was made over the PT and PRP was injected into multiple sites on the PT. The control group (n = 8) was injected with saline. PTs were harvested 7 and 28 days after injection. Hematoxylin-eosin staining showed hypercellularity in the PRP group at 7 days, but the effect was not as marked at 28 days. At 7 days, polarized microscopy showed increased crimp density of collagen in the PRP group, compared with the control group, demonstrating up-regulation in collagen matrix. Cellular proliferation measured by tritiated thymidine was also significantly increased (P = .02) in the PRP group, compared with the control group, but the difference was not as significant at 28 days. At 7 and 28 days, there were no significant changes in basic fibroblast growth factor, insulin-like growth factor, vascular endothelial growth factor, or platelet-derived growth factor with 2B chains. Injection of PRP into rabbit PT enhances collagen remodeling and hypercellularity with increased metabolic activity, which could have a positive effect on healing.
authors.affiliation: Orthopaedic Surgery and Sports Medicine, San Diego, CA, USA.
authors.forename: John G
authors.initials: JG
authors.lastname: Lane
authors.forename: Robert M
authors.initials: RM
authors.lastname: Healey
authors.forename: Derek C
authors.initials: DC
authors.lastname: Chase
authors.forename: David
authors.initials: D
authors.lastname: Amiel
mesh_terms: D000818:Animals; D049109:Cell Proliferation; D003094:Collagen / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D007334:Insulin-Like Growth Factor I / Q000378:metabolism; D017847:Patellar Ligament / Q000378:metabolism / Q000503:physiopathology; D010982:Platelet-Derived Growth Factor / Q000378:metabolism; D053657:Platelet-Rich Plasma; D011817:Rabbits; D013708:Tendon Injuries / Q000378:metabolism / Q000503:physiopathology / Q000628:therapy*; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*
chemical_list: D010982:Platelet-Derived Growth Factor; D042461:Vascular Endothelial Growth Factor A; D016222:Fibroblast Growth Factor 2; D007334:Insulin-Like Growth Factor I; D003094:Collagen