Effects of intra-articular corticosteroid versus platelet- rich plasma on induced knee osteoarthritis in adult albino rats. Histological and anatomical study

ABSTRACTBackground: Osteoarthritis (OA) is a common degenerative joint disease. Intra-articular injection of microcrystalline corticosteroid and platelet- rich plasma (PRP) are used for pain relief of knee OA.Aim of the Study: the goal of this study was to assess the possible therapeutic effects of corticosteroid compared to PRP in a rat model of induced OA.Material and Methods: Intra-articular injection of monosodium iodoacetate (MIA) was used for induction of OA in rats. Blood was collected from12 adult male rats for PRP preparation. 54 adult female albino rats were divided into control groups, OA model group and treated groups which received CS or PRP. All rats were euthanized after 28 days. Left knee joints were processed for histological examination by light microscope after staining by H& E, toluidine blue and masson’s trichrome stains. Right knee joints were grossly examined by stereomicroscope and scanning electron microscope (SEM). The obtained data were examined, further statistically analyzed and interpreted. Results: MIA caused gross anatomical and histological alterations in rat’s articular cartilage similar to human knee OA. Articular cartilage of corticosteroid and PRP treated knee joints showed thinning of the articular cartilage, fibrillation and presence of pannus- like tissue. These groups also showed significant increase in histopathological scores compared to the control group and OA model group in addition to gross macroscopic changes that were confirmed by SEM.Conclusion: This study showed that neither corticosteroid nor PRP could limit the structural changes in osteoarthritis and that different PRP preparation techniques have yielded varying results.