Recent Achievements in the Development of Biomaterials Improved with Platelet Concentrates for Soft and Hard Tissue Engineering Applications.

Platelet concentrates such as platelet-rich plasma, platelet-rich fibrin or concentrated growth factors are cost-effective autologous preparations containing various growth factors, including platelet-derived growth factor, transforming growth factor ß, insulin-like growth factor 1 and vascular endothelial growth factor. For this reason, they are often used in regenerative medicine to treat wounds, nerve damage as well as cartilage and bone defects. Unfortunately, after administration, these preparations release growth factors very quickly, which lose their activity rapidly. As a consequence, this results in the need to repeat the therapy, which is associated with additional pain and discomfort for the patient. Recent research shows that combining platelet concentrates with biomaterials overcomes this problem because growth factors are released in a more sustainable manner. Moreover, this concept fits into the latest trends in tissue engineering, which include biomaterials, bioactive factors and cells. Therefore, this review presents the latest literature reports on the properties of biomaterials enriched with platelet concentrates for applications in skin, nerve, cartilage and bone tissue engineering.

Therapeutic applications of canine platelets and their derivatives: a narrative review.

Platelets contain a multitude of growth factors and play a crucial role in physiological processes such as thrombogenesis, tissue repair, and angiogenesis. As a result, platelet-derived products have significant potential for efficient utilization in the realm of regenerative medicine due to their therapeutic and biological attributes. Numerous studies have already substantiated the therapeutic viability of platelets in various canine ailments. The existing literature indicates a substantial surge in the clinical application of canine platelets, positioning platelet-derived products as a viable alternative to conventional therapeutic agents. Platelet concentrates, including platelet-rich plasma and platelet-rich fibrin are commonly used as a therapeutic modality in clinical cases. These therapeutic derivatives exhibit effectiveness in tissue regeneration and can serve as complementary therapies. Notably, they offer a cost-effective and easily accessible therapeutic option, which has demonstrated its benefits in chronic inflammatory disorders such as osteoarthritis and tendinitis, ophthalmic conditions, wound healing, and mandibular injuries in canine patients. The broad spectrum of therapeutic effects displayed by platelets is providing researchers with novel perspectives for crafting therapeutic models in future investigations. This review centers on exploring the therapeutic potential of canine platelets across diverse disorders. Further exploration into platelet products, encompassing their preparation and applicability in canine medicine, is imperative. These inquiries hold the promise of unveiling fresh horizons for the domain of regenerative medicine.

Production of Modified Autologous Conditioned Serum and Ex Vivo Assessment of Its Healing Potential in Murine Corneal Epithelium.

Human blood-derived topical therapies have been a boon to clinicians in recent decades. Autologous serum (AS) and platelet-rich plasma (PRP) are enriched in epitheliotropic growth factors that are essential in corneal wound healing. Unlike AS, PRP is based on a differential centrifugation system, yielding more platelet-derived growth factors. Autologous conditioned serum (ACS) not only preserves the preparation of AS and PRP, but also focuses on immune-modulating properties, which are important in inflammatory diseases. The lack of standardized protocols and high preparation costs are limitations for the clinical application of ACS. This video experiment demonstrates a standard operating procedure for preparing modified autologous conditioned serum (mACS) eye drops. First, glycerol was added into heparin syringes as the blood cell stabilizer during hypoxic incubation. To activate the blood cells, a 4 h incubation at 37 °C was initiated. Then, the blood samples were centrifuged at 3,500 × g for 10 min at room temperature. After filtration of the supernatant through a 0.22 µm filter, the mACS eye drops were fully prepared. A tentative try-out of the therapeutic effect of mACS showed that it may have competitive advantages over conventional AS in the corneal wound healing in ex vivo mouse eyes. The AS used in this study was prepared according to published studies and the clinical practice in our hospital. Therefore, the efficacy of mACS on ocular surface diseases could be evaluated in future research through in vivo animal studies and clinical trials.

Histological effect of platelet-rich plasma on temporomandibular joint osteoarthritis: systematic review in animal models

SUMMARY: The aim of this systematic review was to assess the histological effects of platelet-rich plasma (PRP) on temporomandibular joint osteoarthritis (TMJ-OA) in animal models. A systematic search was performed using PubMed, WoS, EMBASE, Science Direct and SCOPUS databases. The inclusion criteria were experimental studies in animal models that evaluated the use of PRP as a treatment for TMJ-OA with or without arthrocentesis/arthroscopy. Comparison was made to a healthy control group or to other treatment. The variables evaluated were the histological effects of the treatments, characteristics of the primary articles, characteristics of the sample studied and the risk of bias. The systematic search identified 120 studies. Eventually 5 studies were included in the analysis. Four of the studies showed a statistically significant repair in joint tissues and improvement of cartilage thickness in animals treated with PRP. The global risk of bias was unclear. The results of this systematic review suggest that PRP treatment in TMJ-OA has benefits at the histological level in cartilage, articular disc and articular bone tissue in animal models. However, due to the low number of studies and the risk of bias, further research is needed to recommend its use.

El objetivo de esta revisión sistemática fue evaluar los efectos histológicos del plasma rico en plaquetas (PRP) en la osteoartritis de la articulación temporomandibular (ATM-OA) en modelos animales. Se realizó una búsqueda sistemática en las bases de datos PubMed, WoS, EMBASE, Science Direct y SCOPUS. Los criterios de inclusión fueron estudios experimentales en modelos animales que evaluaran el uso de PRP como tratamiento para la ATM-OA con o sin artrocentesis/ artroscopia. La comparación se realizó con un grupo de control sano o con otro tratamiento. Las variables evaluadas fueron los efectos histológicos de los tratamientos, las características de los artículos primarios, las características de la muestra estudiada y el riesgo de sesgo. La búsqueda sistemática identificó 120 estudios. Finalmente se incluyeron 5 estudios en el análisis. Cuatro de los estudios mostraron una reparación estadísticamente significativa en los tejidos articulares y una mejora del grosor del cartílago en los animales tratados con PRP. El riesgo global de sesgo fue incierto. Los resultados de esta revisión sistemática sugieren que el tratamiento con PRP en la ATM-OA tiene beneficios a nivel histológico en el cartílago, el disco articular y el tejido óseo articular en modelos animales. Sin embargo, debido al escaso número de estudios y al riesgo de sesgo, se necesitan investigaciones adicionales para recomendar su uso.

Molecular and Biologic Effects of Platelet-Rich Plasma (PRP) in Ligament and Tendon Healing and Regeneration: A Systematic Review.

Platelet-rich plasma (PRP) has been introduced and applied to a wide spectrum of acute and chronic ligament and tendon pathologic conditions. Although the biological effect of PRP has been studied thoroughly in both animal and human studies, there is no consensus so far on the exact mechanism of its action as well as the optimal timing and dosage of its application. Therefore, we conducted a systematic review aiming to evaluate the molecular effect of the administration of PRP in tendoligamentous injuries and degenerative diseases. The literature search revealed 36 in vitro and in vivo studies examining the healing and remodeling response of animal and human ligament or tendon tissues to PRP. Platelet-rich plasma added in the culture media was highly associated with increased cell proliferation, migration, viability and total collagen production of both ligament- and tendon-derived cells in in vitro studies, which was further confirmed by the upregulation of collagen gene expression. In vivo studies correlated the PRP with higher fibroblastic anabolic activity, including increased cellularity, collagen production and vascularity of ligament tissue. Similarly, greater metabolic response of tenocytes along with the acceleration of the healing process in the setting of a tendon tear were noticed after PRP application, particularly between the third and fourth week after treatment. However, some studies demonstrated that PRP had no or even negative effect on tendon and ligament regeneration. This controversy is mainly related to the variable processes and methodologies of preparation of PRP, necessitating standardized protocols for both investigation and ap-plication.

Advances and prospects of platelet-rich plasma therapy in veterinary ophthalmology.

In the recent decades, there has been a significant uptick on the use of platelet-rich plasma (PRP) as a better alternative for ophthalmologic therapies in pathologies, primarily of the ocular surface. PRP is a class of liquid platelet concentrate containing a supra-physiological concentration of platelets in a relatively small amount of plasma. Its potential to heal various tissues has piqued interest in its therapeutic application as a biomaterial in regenerative medicine. It is currently a popular therapeutic agent in plastic surgery, cardiothoracic surgery, reconstructive surgery, and even oral and maxillofacial surgery. Based on the data from in vitro and in vivo studies, it can be concluded that PRP possesses adequate therapeutic potential in ocular pathologies, especially those involving cornea. In addition, the high concentrations of growth factors (TGF-ß, VEGF, EGF) present in the PRP accelerate the healing of the corneal epithelium. PRP has great therapeutic prospects in veterinary ophthalmology as a regenerative therapeutic modality. However, several variables are yet to be defined and standardized that can directly affect the efficacy of PRP application in different ophthalmic conditions. There is a shortage of research on the use of PRP in ocular surface defects compared to the number of studies and reports on the use of autologous and allogeneic serum eye drops. Therefore, a data-driven approach is required to generate consensus/guidelines for the preparation, characterization, and therapeutic use of PRP in veterinary ophthalmology. This review aims to inform readers of the latest research on PRP, including its preparation methods, physiological and biochemical properties, clinical applications in veterinary ophthalmology, and their safety and efficacy.

The Biological Use of Platelet-Rich Plasma in Skeletal Muscle Injury and Repair.

Platelet-rich plasma (PRP) is a blood product that contains several growth factors and active proteins. PRP is thought to be used autologously to assist in the repair of injured tissues as well as to treat pain at the site of injury. The mechanism behind PRP in regenerative medicine has been well investigated and includes the identification and concentration of released growth factors and exosomes. The benefits of PRP have been highly recommended and are used widely in orthopaedics and sports medicine, including repair of injured skeletal muscle. This current report summarizes some of the more recent studies in the use of PRP as it relates to muscle healing, in both the in vitro and clinical arenas.

Lyophilized Platelet-rich plasma for the management of thin endometrium and facilitation of in-vitro fertilization.

OBJECTIVE: Adequate endometrial thickness has been considered an important parameter for hormonal response and blastocyst implantation in assisted reproduction therapies. While there is no consensus on the exact thickness of the endometrium considered 'adequate,' a thin endometrium (<7mm) has been associated with compromised outcomes in assisted reproduction therapies. Platelet-rich plasma (PRP), which is a concentrate obtained from peripheral blood, is a rich source of growth factors that play important roles in various cellular processes. The objective is to utilize lyophilized PRP (LPRP) to increase the thickness of the endometrium and enhance the outcomes of embryo transfer in women with poor response to previous in-vitro fertilization procedures. METHODS: This study enrolled nine women between 23 and 42 years of age, with a thin endometrium, who had undergone multiple previous unsuccessful assisted reproduction procedures. All patients underwent intrauterine infusion of LPRP, followed by frozen-thawed embryo transfer after 2-3 days. RESULTS: Endometrial thickness was assessed by ultrasound 2 weeks after LPRP infusion, which showed improved thickness in all patients (range, 0.7-2.2mm). Clinical pregnancy occurred in all patients and eight out of nine patients are currently between 9 weeks and 27 weeks of gestation. Twin fetal heartbeats were not detected at the eighth week in one patient. CONCLUSION: Infusion of LPRP was found to be beneficial to increase endometrium thickness in all patients. This regenerative technique could be considered to enhance the outcomes of assisted reproduction techniques in a minimally-invasive manner, without any side effects.

Orthobiologic Interventions for Muscle Injuries.

Muscle injuries represent a common problem in active populations. Orthobiologics continue to be studied for their ability to improve muscle healing. To date, the basic science research for treating muscle injuries with platelet-rich plasma or stem cell remains novel. Furthermore, there are even fewer clinical studies on these topics, and their findings are inconclusive. Reviewing the literature, muscle injuries treated with ultrasound-guided leukocyte-rich PRP injections appear to have the strongest evidence. Scar formation remains a major barrier in muscle injury healing, and there is optimism for future orthobiologic treatments that target the downregulation of TGF-B, resulting in decreased scar development.

Effect of intrauterine infusion of platelet-rich plasma for women with recurrent implantation failure: a systematic review and meta-analysis.

This study evaluated the effect of intrauterine perfusion of autologous platelet-rich plasma (PRP) on pregnancy outcomes in women with recurrent implantation failure (RIF). Key biomedical databases were searched to identify relevant clinical trials and observational studies. Outcomes included clinical pregnancy rate, chemical pregnancy rate, implantation rate, live birth rate, and abortion rate. Data was extracted from ten studies (six randomised controlled trials, four cohort studies) involving 1555 patients. Pregnancy outcomes were improved in women treated with PRP compared to controls: clinical pregnancy rate (RR = 1.96, 95% CI [1.67, 2.31], p < 0.00001, I2 = 46%), chemical pregnancy rate (RR = 1.79, 95% CI [1.54, 2.08], p < 0.00001, I2 = 29%), implantation rate (RR = 1.90, CI [1.50, 2.41], p < 0.00001, I2 = 0%), live birth rate (RR = 2.83, CI [1.45, 5.52], p = 0.0007, I2 = 83%), abortion rate (RR = 0.40, 95% CI [0.18, 0.90], p = 0.03, I2 = 59%). These data imply PRP has potential to improve pregnancy outcomes in women with RIF, suggesting a promising role in assisted reproductive technology.IMPACT STATEMENTWhat is already known on this subject? Platelet-rich plasma (PRP) is an autologous blood product that contains platelets, various growth factors, and cytokines at concentrations above the normal baseline level. Recent studies have shown that intrauterine infusion of autologous PRP can improve pregnancy outcomes in infertile women.What do the results of this study add? This systematic review and meta-analysis of data from ten studies (n = 1555; 775 cases and 780 controls) investigated the effect of intrauterine perfusion of autologous PRP on pregnancy outcomes in women with recurrent implantation failure (RIF). Findings suggest that pregnancy outcomes, including clinical pregnancy rate, chemical pregnancy rate, implantation rate, live birth rate and abortion rate were improved in women treated with PRP compared to controls.What are the implications of these findings for clinical practice and/or further research? RIF remains a challenge for researchers, clinicians, and patients. Our study identified PRP as a potential intervention in assisted reproduction. As an autologous blood preparation, PRP eliminates the risk of an immune response and transmission of disease. PRP is low cost and effective and may represent a new approach to the treatment of patients with RIF.

Comparison of the clinical effectiveness of activated and non-activated platelet-rich plasma in the treatment of knee osteoarthritis: a systematic review and meta-analysis.

INTRODUCTION/OBJECTIVES: Platelet-rich plasma (PRP) has shown to be clinically effective in the treatment of knee osteoarthritis (OA). Notwithstanding, some inconsistences remain due to methodological differences in PRP preparation such as the use (or not) of activation strategies. We aimed to evaluate whether the use of non-activated PRP would be as effective as activated PRP in patients with knee OA. METHOD: All randomized, placebo-controlled trials were identified through a search in MEDLINE, EMBASE, Scopus, and Web of Science up to June 2022. Pre- and post-injection pain and function scores were collected. The meta-analysis was conducted with a random-effects model and generic inverse variance method. Effect sizes were estimated using standardized mean differences (SMD). RESULTS: Fourteen clinical trials involving 1292 subjects were included for meta-analysis. Exogenous activation of PRP revealed a significant pain relief (SMD, - 1.05 [95% CI - 1.58 to - 0.52]; p = 0.0001) and a significant functional improvement (SMD, - 1.21 [95% CI - 1.75 to - 0.67]; p < 0.0001) unlike studies describing the use of a non-activated PRP. The sensitivity analysis indicated that the effect size for both outcomes was not influenced by a single study. CONCLUSIONS: The results of this systematic review suggest that the use of an exogenously activated PRP is more effective in improving both pain and functional scores in patients with knee OA. Key Points • Results from meta-analysis suggest that exogenously activated PRP is clinically more effective than non-activated PRP. • The use of an activated PRP was more frequently reported by the included studies. • The most frequent method for activation was the use of calcium chloride (CaCl2).

Patient-Reported Quality of Life versus Physical Examination in Treating Temporomandibular Disorders with Intra-Articular Platelet-Rich Plasma Injections: An Open-Label Clinical Trial.

Temporomandibular disorders, often manifested by articular pain, limitation of the mouth opening range, and unpleasant acoustic symptoms originating from inside the joint, have been associated with reduced quality of life. These symptoms, among others, can be treated with intra-articular injections of various substances, including repeated platelet-rich plasma (PRP) administration. The reported study was designed as an uncontrolled open-label clinical trial of consecutive cases. The participants completed a Fonseca questionnaire and evaluated acoustic symptoms, and spontaneous and provoked pain on VAS, and were subjected to a physical examination before, during, and after PRP therapy. The total Fonseca questionnaire results were statistically significantly (p < 0.05) correlated with 340 out of 348 (98%) other variables. The fully subjective assessment of the presence and intensity of acoustic symptoms coming from the temporomandibular joints was correlated with the physical examination results (0.45-0.63) and the maximum mouth opening with the maximum pain-free mouth opening (0.73-0.87). There were no correlations observed between the patient's and the physician's assessment of mandibular mobility. The Fonseca questionnaire seems to cover the entire spectrum of temporomandibular disorders, making it a balanced tool for assessing the quality of life in TMDs. However, it is worth considering extending the standard 3-point response scale to an 11-point one. The patient is somewhat able to perform a self-diagnosis with regard to the acoustic symptoms, but it is not possible for them to determine without measurement whether the range of mandibular mobility is appropriate..

Current State of Platelet-Rich Plasma and Cell-Based Therapies for the Treatment of Osteoarthritis and Tendon and Ligament Injuries.

➤: Orthobiologics encompass numerous substances that are naturally found in the human body including platelet-rich plasma (PRP), isolated growth factors, and cell therapy approaches to theoretically optimize and improve the healing of cartilage, fractures, and injured muscles, tendons, and ligaments. ➤: PRP is an autologous derivative of whole blood generated by centrifugation and is perhaps the most widely used orthobiologic treatment modality. Despite a vast amount of literature on its use in osteoarthritis as well as in tendon and ligament pathology, clinical efficacy results remain mixed, partly as a result of insufficient reporting of experimental details or exact compositions of PRP formulations used. ➤: Mesenchymal stromal cells (MSCs) can be isolated from a variety of tissues, with the most common being bone marrow aspirate concentrate. Similar to PRP, clinical results in orthopaedics with MSCs have been highly variable, with the quality and concentration of MSCs being highly contingent on the site of procurement and the techniques of harvesting and preparation. ➤: Advances in novel orthobiologics, therapeutic targets, and customized orthobiologic therapy will undoubtedly continue to burgeon, with some early promising results from studies targeting fibrosis and senescence.

The use of intraovarian injection of autologous platelet rich plasma (PRP) in patients with poor ovarian response and premature ovarian insufficiency.

PURPOSE OF REVIEW: Intraovarian injection of platelet rich plasma (PRP) is a novel treatment for patients with poor ovarian response (POR) and primary ovarian insufficiency (POI). This article reviews the latest literature on the effect of PRP on markers of ovarian reserve, oocyte and embryo yield, and live birth for these poor prognosis patients. RECENT FINDINGS: Several case series and one prospective trial have demonstrated improvements in markers of ovarian reserve in patients with POI and POR and improved oocyte and embryo yields in patients with POR. These studies report multiple live births in patients who had previously failed treatment. The positive effects of PRP persist throughout the literature despite the fact that multiple protocols for preparing and injecting PRP exist, with no consensus on the optimal protocol. SUMMARY: Intra-ovarian injection of PRP is a promising new technology for poor prognosis patients. Rigorous and appropriately controlled clinical trials are warranted to confirm the utility of this treatment for improving patients' ability to successfully conceive.

Effect Evaluation of Platelet-Rich Plasma Combined with Vacuum Sealing Drainage on Serum Inflammatory Factors in Patients with Pressure Ulcer by Intelligent Algorithm-Based CT Image.

This work was to explore the efficacy of intelligent algorithm-based computed tomography (CT) to evaluate platelet-rich plasma (PRP) combined with vacuum sealing drainage (VSD) in the treatment of patients with pressure ulcers. Based on the u-net network structure, an image denoising algorithm based on double residual convolution neural network (Dr-CNN) was proposed to denoise the CT images. A total of 84 patients who were hospitalized in hospital were randomly divided into group A (without any intervention), group B (PRP treatment), group C (VSD treatment), and group D (PRP+VSD treatment). Procalcitonin (PCT) was detected by enzyme-linked immunosorbent assay (ELISA) combined with immunofluorescence method, C-reactive protein (CRP) was detected by rate reflectance turbidimetry (RRT), and interleukin-6 (IL-6) was detected by electrochemiluminescence method. The results showed that after treatment, 44 cases (52.38%) of pressure ulcers patients recovered, 24 cases (28.57%) had no change in stage, and 16 cases (19.04%) developed pressure ulcers. The pain scores of group D at 1 week (3.35 ± 0.56 points) and 2 weeks (2.76 ± 0.55 points) after treatment were significantly lower than those in group C (7.77 ± 0.58 points and 6.34 ± 0.44 points, respectively). The time of complete wound healing in group D (24.5 ± 2.32) was obviously lower in contrast to that in groups A, B, and C (35.54 ± 3.22 days, 30.23 ± 2 days, and 29.34 ± 2.15 days, respectively). In addition, the medical satisfaction of group D (8.74 ± 0.69) was significantly higher than that of groups A, B, and C (4.69 ± 0.85, 5.22 ± 0.31, and 5.18 ± 0.59, respectively). The levels of IL-6 and PCT in group D were lower than those in groups A, B, and C, and the differences were statistically significant (P < 0.01). The average values of peak signal to noise ratio (PSNR) and structural similarity index measure (SSIM) of the Dr-CNN network model were 37.21 ± 1.09 dB and 0.925 ± 0.01, respectively, which were higher than other algorithms. The mean values of root mean square error (MSE) and normalized mean absolute distance (NMAD) of the Dr-CNN network model were 0.022 ± 0.002 and 0.126 ± 0.012, respectively, which were significantly lower than other algorithms (P < 0.05). The experimental results showed that PrP combined with VSD could significantly reduce the inflammatory response of patients with pressure ulcers. PRP combined with VSD could significantly reduce the pain of dressing change for patients. Moreover, the performance model of image denoising algorithm based on double residual convolutional neural network was better than other algorithms.

Therapeutic options for premature ovarian insufficiency: an updated review.

Primary ovarian insufficiency (POI) is a rare gynecological condition. This disease causes menstrual disturbances, infertility, and various health problems. Historically, hormone replacement therapy is the first-line treatment for this disorder. Women diagnosed with POI are left with limited therapeutic options. In order to remedy this situation, a new generation of therapeutic approaches, such as in vitro activation, mitochondrial activation technique, stem cell and exosomes therapy, biomaterials strategies, and platelet-rich plasma intra-ovarian infusion, is being developed. However, these emerging therapies are yet in the experimental stage and require precise design components to accelerate their conversion into clinical treatments. Thus, each medical practitioner bears responsibility for selecting suitable therapies for individual patients. In this article, we provide a timely analysis of the therapeutic strategies that are available for POI patients and discuss the prospects of POI therapy.

Ovarian response to intraovarian platelet-rich plasma (PRP) administration: hypotheses and potential mechanisms of action.

PURPOSE: Platelet-rich plasma (PRP) therapy has been used as an adjunct to fertility treatments in women with very low ovarian reserve and premature ovarian insufficiency. Recent literature in both humans and animals suggest that intraovarian PRP administration in the setting of poor ovarian reserve may help ovarian function and increase the chances of pregnancy. METHODS: A comprehensive literature search through PubMed, MEDLINE databases, and recent abstracts published at relevant society meetings was performed and resulted in 25 articles and 2 abstracts published that studied effect of PRP on the ovaries for the purpose of reproduction. RESULTS: This review article presents all the data published to date pertaining to intraovarian PRP injection and pregnancy, both naturally and after in vitro fertilization. It also presents the most recent data on the use of ovarian PRP in in vitro and animal model studies highlighting the possible mechanisms by which PRP could impact ovarian function. CONCLUSIONS: Even though recent commentaries questioned the use of PRP as an "add-on" therapy in fertility treatment because it has not been thoroughly studied, the recent basic science studies presented here could increase awareness for considering more serious research into the efficacy of PRP as an adjunct for women with poor ovarian reserve, premature ovarian insufficiency, and even early menopause who are trying to conceive using their own oocytes. Given its low-risk profile, the hypothetical benefit of PRP treatment needs to be studied with larger randomized controlled trials.

Intra-Articular Platelet-Rich Plasma Injections in Knee Osteoarthritis: A Review of Their Current Molecular Mechanisms of Action and Their Degree of Efficacy.

Knee osteoarthritis (OA) is estimated to affect more than 10% of the population, with a lifetime risk of 45%. Contemporary guidelines advise control of body weight, therapeutic physical exercise, drug treatment (oral non-steroidal anti-inflammatory drugs, paracetamol, opioids), and mechanical aids (walking aids, braces, orthoses). Nevertheless, these treatments typically have only short-term benefits. Intra-articular corticosteroids are typically advised, but only for short-term pain alleviation, given that their benefits last only a few weeks. The efficacy of hyaluronic acid is controversial. When the aforesaid options fail, total knee arthroplasty is generally recommended as an efficacious treatment. However, it is costly and can involve medical and postoperative complications. Therefore, determining alternate safe and effective treatments for knee OA is paramount. Platelet-rich plasma (PRP) has lately been investigated for the treatment of knee OA. This article reviews recent knowledge concerning PRP's molecular mechanisms of action. The effectiveness of intra-articular PRP injections in the knee joint remains controversial, although most recent publications show pain alleviation in the short term. Orthopedic surgeons treating people with knee OA are becoming increasingly interested in PRP, despite indecisive clinical data and basic science information. Further studies comparing PRP with placebo are required.