Objective: The aim of the present study was to evaluate the effects of PRP on Achilles tendon healing inrabbits during the inflammatory, proliferative, and remodeling phases by histological examination andquantitative assessments.Methods: Fifty mature male Japanese albino rabbits with severed Achilles tendons were divided into twoequal groups and treated with platelet-rich plasma (PRP) or left untreated. Tendon tissue was harvestedat 1, 2, 3, 4, and 6 weeks after treatment, and sections were stained with hematoxylin-eosin andmonoclonal antibodies against CD31 and type I collagen.Results: CollagenŞbers proliferated more densely early after severance, and subsequent remodeling ofthe collagenŞbers and approximation of normal tendinous tissue occurred earlier in the PRP group thanin the control group. TheŞbroblast number was signiŞcantly higher in the PRP group than in the controlgroup at 1 and 2 weeks. Similarly, the area ratio of CD31-positive cells was signiŞcantly higher in the PRPgroup than in the control group at 1 and 2 weeks. Positive staining for type I collagen was more intensein the PRP group than in the control group after 3 weeks, indicating tendon maturation.Conclusion: Administration of PRP shortened the inflammatory phase and promoted tendon healingduring the proliferative phase.© 2016 Turkish Association of Orthopaedics and Traumatology. Publishing services by Elsevier B.V. This is anopen access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)
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