Substantial Variability in Platelet-Rich Plasma Composition Is Based on Patient Age and Baseline Platelet Count

Platelet like cells differentiated from human adipose derived mesenchymal stem cells promote healing of tendinopathy in rats

Tendon and ligament disorders, such as tendinopathy, cause pain and limit levels of activities of daily living. Thus, devising methods to heal them is crucial. Although treatment with autologous platelet rich plasma (PRP) is reportedly useful against tendon injury, PRP requires blood sampling and its quality varies. Here we show that platelet-like cells (ASCL-PLCs) derived from a heterologous human adipose-derived mesenchymal stem cell line (ASCL) promote significant tendon repair in a collagenase-induced injury model in rat Achilles tendons. Single administration of human ASCL-PLCs to rat Achilles tendon after 2 weeks of collagenase treatment significantly increased tendon strength and improved semi-quantitative histological evaluation scores in 4 weeks relative to PBS-treated controls. Moreover, xeno-graft reactions were not evident in ASCL-PLC-administered rats. In vitro, ASCL-PLC treatment significantly upregulated Col1a1, Lox and Mkx gene expression in NIH3T3 fibroblasts and activated ERK signaling. Overall, ASCL-PLCs could serve as a useful tool to repair injured tendons and treat tendinopathy. This approach eliminates the need for blood sampling, ensures consistent quality, supports xeno-transplantation, and increases injured tendon strength.

Minimum reporting requirements for platelet-rich plasma in biomaterial research

Platelet-rich plasma (PRP) is gaining significant attention in regenerative medicine, offering an abundance of growth factors and bioactive molecules that promote tissue repair and healing. In biomaterial research, PRP is often incorporated into scaffolds to enhance their bioactivity, facilitating cell attachment, proliferation, and differentiation for improved tissue regeneration. However, inconsistencies in outcomes and variability across studies hinder its clinical translation. These challenges are primarily attributed to the lack of standardized reporting criteria for PRP characterization, which limits reproducibility and cross-study comparisons. Accurate characterization of PRP is essential for understanding its biological activity and therapeutic potential. Key parameters include platelet, white blood cell, and red blood cell concentrations. Recent classification systems, such as those proposed by the ISTH Subcommittee on Platelet Physiology, emphasize the importance of these parameters in categorizing PRP types. Establishing minimal reporting requirements helps address variability in PRP studies, ensuring consistency and transparency in the methodology and results. By adopting these standards as mandatory reporting requirements, researchers can reduce variability, enhance the credibility of their findings, and facilitate the development of standardized protocols for PRP-based therapies.

YouTube Is an Inconsistent Source of Information on Orthobiologics: Implications for Content Quality, Reliability, Comprehensiveness, and Patient Decision Making

PURPOSE

To assess the reliability, quality, and completeness of YouTube videos on orthobiologics and evaluate whether the content aligns with current clinical evidence and regulatory guidelines.

METHODS

One hundred YouTube videos on orthobiologics were analyzed using the Journal of the American Medical Association (JAMA) benchmark score, the Global Quality Scale (GQS), the modified DISCERN questionnaire, and an orthobiologics grading system (OGS). Video views, duration, source, and content type were examined to determine their impact on informational quality.

RESULTS

Of the 100 videos reviewed, 18 were excluded for reasons such as unrelated content or duplication, leaving 82 for analysis. The average number of views per video was 5,217, with a total of 427,825 views. Most videos (33%) were uploaded by independent users, whereas only 1% were from government or news agencies. The mean JAMA score was 2.8 (indicating low-moderate transparency and credibility); GQS score, 3.2 (reflecting moderate overall quality); modified DISCERN score, 3.7 (representing moderate reliability in discussion of treatments); and OGS score, 9.6 (indicating limited comprehensiveness with many videos lacking critical details). There were no significant associations between video source or verification status and any scoring metrics (P > .05). Longer videos were associated with higher JAMA, GQS, DISCERN, and OGS scores (P < .05). Health information websites had higher OGS scores (P = .001).

CONCLUSIONS

YouTube videos on orthobiologics show low to moderate reliability and quality, with limited comprehensiveness. Most content is produced by independent users, with minimal contributions from verified health organizations. Longer videos were associated with higher quality scores, whereas verification status and video source showed no significant correlation with content quality.

CLINICAL RELEVANCE

Given YouTube's role as a health information source, this study highlights the need to enhance the quality of educational content on orthobiologics to better support patient understanding and decision making.

Platelet-Derived Growth Factor as Biomarker of Clinical Outcome for Autologous Platelet Concentrate Therapy in Grade I Knee Osteoarthritis

Introduction

Autologous platelet concentrates (APC) are widely used in the infiltrative treatment of knee osteoarthritis (OA) to enhance tissue healing and relieve pain. Aim of this study was to identify predictive biomarkers for clinical outcomes in patients with grade I knee OA.

Methods

A panel of growth factors (GFs) and cytokines was determined in peripheral blood (PB) and APC. The Numeric Pain Rating Scale (NPRS) was used as a clinical readout before and after the APC infiltration.

Results

A lower white blood cell (WBC) count and higher Monocyte-chemoattractant Protein-1 levels in PB were associated with APC-induced pain relief. Platelet-derived Growth Factor (PDGF) levels in APC were significantly higher in OA patients displaying a larger NPRS reduction, independent of platelet count. Finally, the simultaneous determination of PDGF, Vascular Endothelial Growth Factor, and Macrophage Inflammatory Protein-1α in APC discriminated OA patients with very poor or no response.

Conclusion

Platelet-released GFs rather than platelet counts may predict clinical outcomes in grade 1 knee OA.

Orthopaedic Musculoskeletal Biologics Research Impacts Patient Care: The Third Annual Arthroscopy: The Journal of Arthroscopic and Related Surgery Orthobiologics Virtual Special Issue

Orthobiologics represent a rapidly advancing field of research in musculoskeletal care, providing novel therapies to modify symptoms and potentially augment tissue regeneration when used in the clinical or operative setting. These treatments are derived from autologous cells, tissues, and blood components, yielding bioactive elements that may promote healing, reduce symptoms, and be associated with improved patient outcomes. Biologic therapies such as platelet-rich plasma, bone marrow aspirate concentrate, adipose-derived products, and amniotic allograft tissues have demonstrated favorable clinical outcomes. Arthroscopy: The Journal of Arthroscopic and Related Surgery and its companion journals are committed to advancing the field by publishing high-quality, peer-reviewed orthobiologics research. This anthology of articles showcases significant recent advancements in musculoskeletal orthobiologics research.

Cell Homing Strategies in Regenerative Endodontic Therapy

Cell homing, a process that leverages the body's natural ability to recruit cells and repair damaged tissues, presents a promising alternative to cell transplantation methods. Central to this approach is the recruitment of endogenous stem/progenitor cells-such as those from the apical papilla, bone marrow, and periapical tissues-facilitated by chemotactic biological cues. Moreover, biomaterial scaffolds embedded with signaling molecules create supportive environments, promoting cell migration, adhesion, and differentiation for the regeneration of the pulp-dentin complex. By analyzing in vivo animal studies using cell homing strategies, this review explores how biomolecules and scaffold materials enhance the recruitment of endogenous stem cells to the site of damaged dental pulp tissue, thereby promoting repair and regeneration. It also examines the key principles, recent advancements, and current limitations linked to cell homing-based regenerative endodontic therapy, highlighting the interplay of biomaterials, signaling molecules, and their broader clinical implications.

Demographic, anthropometric and intrasubject variations affect platelet-rich plasma formulation

Purpose

The purpose of this study is to describe the inter- and intra-individual differences in the platelet concentration between blood and platelet-rich plasma (PRP) preparation, assess intersubject differences considering demographic and anthropometric variables, describe PRP code distribution and analyse intrasubject variability.

Methods

A retrospective analysis was conducted using a single-centre patient database from November 2021 to November 2023. It included patients with musculoskeletal pathologies treated with PRP injections. Primary variables were demographic characteristics (sex, age, body mass index [BMI]) and platelet concentrations in blood and PRP during treatments. Secondary analysis focused on PRP code frequency distribution and intrasubject variability according to different coding systems.

Results

Here, 686 patients met the inclusion criteria. PRP exhibited significantly higher platelet concentrations compared to blood (378.01 ± 136.25 × 103 platelets/µL vs. 221.97 ± 58.21 × 103 platelets/µL, p < 0.001). Younger patients had higher platelet concentrations in both blood (p = 0.004) and PRP (p = 0.003), whereas female patients showed higher platelet concentrations only in blood (p < 0.001). The platelet concentration ratio was higher in males (p < 0.001) and those with higher BMI (p = 0.023). Significant differences were found between the existing and modified PRP coding systems (p < 0.001). Intrasubject variability was higher in PRP than in blood (coefficient of variance: 21.32 ± 17.36 in blood vs. 27.85 ± 19.10 in PRP, p < 0.001).

Conclusion

Age, gender, BMI and intrasubject variations significantly affect PRP formulation, emphasizing the importance of addressing these variables for a more predictable, personalized and effective therapeutic approach.

Level of Evidence

This is a retrospective study. Level IV.

A Comprehensive Summary of the Meta-Analyses and Systematic Reviews on Platelet-Rich Plasma Therapies for Knee Osteoarthritis

INTRODUCTION

Osteoarthritis (OA), including that of the knee joint, represents a significant proportion of musculoskeletal injuries in the Canadian Armed Forces (CAF) due to the frequent, high-stress physical activity for which member participation is necessary. Platelet-rich plasma (PRP) is a conservative, autologous treatment that has the potential to relieve symptoms and improve functionality of military members to decrease the impact of the disease and ultimately strengthen the CAF.

MATERIALS AND METHODS

A search of systematic reviews and meta-analyses was conducted to determine the efficacy of PRP injections in treating knee OA. The Scopus database, PubMed database, and Omni academic search tools were scoped for relevant publications. English literature, published up to and including March 2023, that investigated only clinically randomized controlled trials (RCTs) was eligible for inclusion. The results of network meta-analyses were investigated and summarized independent of reviews and non-network meta-analyses.

RESULTS

A total of 225 unique systematic reviews and meta-analyses were initially identified, of which 39 publications, including 7 network meta-analyses, adhered to the defined inclusion and exclusion criteria. PRP was found to significantly alleviate symptoms of pain based on the visual analog scale and Western Ontario and McMaster Universities Arthritis Index pain scores within the 12-month follow-up. Function, activity, sport, quality of life, and stiffness were additionally determined to generally improve to a greater extent from PRP treatment compared to controls, while adverse effects were minor and temporary. PRP placed in the top 3 in 9 reported surface under the cumulative ranking curves, while individually reported rankings of leukocyte-poor and leukocyte-rich PRP both placed in the top 4. The clinical recommendations made were generally positive, with 17 publications acknowledging the benefits of PRP, 3 supporting possible efficacy, and an additional 8 recommending that it be an option for the conservative treatment of knee OA.

CONCLUSION

The results of this review support the efficacy of PRP for relieving symptoms of pain and improving function, stiffness, and quality of life for patients experiencing knee OA within 12 months. As a result, leukocyte-poor-PRP could be considered for members of the CAF with mild to moderate knee OA (Kellgren-Lawrence grades 1-3) to slow the progression of OA and extend the military careers of CAF members. There continues to be a need for future studies to investigate the longer-term effects of PRP to verify sustained benefits at follow-up points greater than 12 months, including findings of improvement in a delayed fashion at the 3- and 6-month timeframe compared to hyaluronic acid treatment.

Current Concepts in Orthobiologics for Achilles Tendon Injuries: A Critical Analysis Review

» Platelet-rich plasma and hyaluronic acid are low-risk and potentially high-reward treatments for Achilles tendinopathy, although clinical studies have yielded mixed results with questionable methodological quality» Case series and reports have reported that bone marrow aspirate, stem cells, and amniotic membrane products can improve functional outcomes, alleviate pain, and facilitate return to sport and activities, but high-level evidence studies are lacking» Exosomes are a promising novel biologic with laboratory studies showing improved collagen organization and cell proliferation, greater tendon mechanical properties, and prevention of extracellular matrix breakdown.» Standardization of protocols with clear reporting is necessary for future studies evaluating orthobiologic therapies for Achilles tendon injuries.

Evidence of restorative therapies in the treatment of Peyronie disease: A narrative review

OBJECTIVE

To describe the evidence of Platelet Rich Plasma (PRP), Stem cells therapy (SCT) and Extracorporeal shockwave therapy (ESWL) for the treatment of Peyronies disease (PD), including information from the main urological society guidelines.

MATERIALS AND METHODS

A literature review of PubMed articles published between 2000 and 2023 was conducted, utilizing keywords such as "Peyronie's Disease", "Penile curvature", "Platelet Rich Plasma", "Stem cells", and "Extracorporeal shockwave therapy". Only full-text articles in English were included, excluding case reports and opinions.

RESULTS

A considerable number of clinical trials were conducted using PRP penile injections for therapy of PD, showing reduction of curvature, plaque size and improvement in quality of life. Preclinical studies in rats have shown the potential benefit of adipose-derived stem cells, with improvements in erectile function and fibrosis. Human studies with mesenchymal stem cells demonstrated promising results, with reduction of curvature and plaque size. ESWL effects on PD were investigated in randomized clinical trials and demonstrated no significant impact in curvature or plaque size, but reasonable effect on pain control.

CONCLUSION

Restorative therapies has emerged as an innovative treatment option for PD and the results from current studies appear to be promising and demonstrated good safety profile. Unfortunately, due to scarce evidence, PRP and SCT are still considered experimental by American Urological Association (AUA) and European Association of Urology (EAU) guidelines. ESWT is recommended, by the same guidelines, for pain control only. More high-quality studies with long-term follow-up outcomes are needed to evaluate efficacy and reproducibility of those therapies.

The Role of Platelet-Rich Plasma in the Management of Sensorineural Hearing Loss: Current Evidence and Emerging Trends

Sensorineural hearing loss (SNHL) is a common form of hearing impairment characterized by damage to the inner ear or auditory nerve, resulting in significant communication difficulties and reduced quality of life. Current treatment options, including hearing aids, cochlear implants, and corticosteroids, primarily focus on symptom management and do not address the underlying pathophysiological damage. Platelet-rich plasma (PRP), an autologous concentrate rich in platelets and growth factors, has emerged as a potential regenerative therapy due to its ability to promote tissue repair and cellular regeneration. This review provides a comprehensive overview of the role of PRP in the management of SNHL, examining the current evidence from preclinical and clinical studies. We discuss the mechanisms through which PRP may promote auditory tissue regeneration and repair, analyze its efficacy and safety profile, and explore innovative approaches and future directions in its application for SNHL. Despite promising preliminary findings, further research is needed to optimize PRP protocols, establish standardized treatment guidelines, and conduct large-scale randomized controlled trials to validate efficacy. This review aims to highlight the potential of PRP as a novel therapeutic strategy in treating SNHL and its possible integration into current clinical practices, offering new hope for patients with this debilitating condition.

Therapeutic Potential of Platelet-Rich Plasma in Fracture Healing: A Comprehensive Review

Fracture healing is a dynamic process essential for the restoration of bone integrity and function. However, factors such as patient age, comorbidities, and the severity of the fracture can impede this process, leading to delayed healing or nonunion. Platelet-rich plasma (PRP) has emerged as a promising therapeutic option for enhancing fracture healing. PRP is an autologous blood product containing a concentrated mixture of platelets, growth factors, and cytokines known to promote tissue regeneration and repair. This comprehensive review provides an overview of the fracture healing process, emphasizing the importance of timely and efficient bone repair. We discuss the mechanisms underlying the purported efficacy of PRP in fracture healing, drawing upon both preclinical and clinical evidence. Preclinical studies in animal models have demonstrated the ability of PRP to accelerate fracture healing, stimulate osteogenesis, and enhance bone regeneration. Clinical studies have yielded mixed results, with some reporting positive outcomes in terms of accelerated healing and improved functional outcomes, while others have shown no significant benefits over standard treatments. Factors influencing the efficacy of PRP, such as timing of administration, PRP concentration, and patient-specific variables, are also examined. Furthermore, safety considerations and potential adverse effects associated with PRP therapy are discussed. Despite the promising preclinical findings, challenges remain in standardizing PRP formulations, optimizing administration protocols, and addressing unanswered questions regarding its long-term efficacy and safety. This review aims to provide insights into the therapeutic potential of PRP in fracture healing, informing future research directions and guiding clinical practice.

Elevated IL-1β and Comparable IL-1 Receptor Antagonist Levels Are Characteristic Features of L-PRP in Female College Athletes Compared to Male Professional Soccer Players

Autologous platelet-rich plasma (PRP) therapy has been becoming popular for the treatment of musculotendinous injuries among athletes. However, for individual and practical variations, clinical success is hardly predictable. To overcome this difficulty, we have been exploring possible criterion candidates for monitoring its clinical effectiveness. In this study, we focused on sex-based differences in young elite athletes and compared the biochemical compositions of their PRP. Leukocyte-rich PRP (L-PRP) was manually prepared from blood samples collected from male professional soccer players (mPSPs) (n = 25) and female college athletes (fCAs) (n = 36). Platelet-derived growth factor-BB (PDGF-BB), transforming-growth factor-β1 (TGFβ1), platelet factor-4 (PF4), interleukin-1β (IL-1β), and IL-1 receptor antagonist (IL-1RA) were quantified using an enzyme-linked immunosorbent assay. The levels of PDGF-BB, TGFβ1, and PF4 in L-PRP were significantly higher in mPSPs than in fCAs. Conversely, IL-1β and IL-1RA were detected at significantly and slightly higher levels, respectively, in fCAs than in mPSPs. Our findings suggest that, even though L-PRP from fCAs may have lower potential to induce cell growth and differentiation than that of mPSPs, due to the latter's higher capacity to control inflammation, it does not necessarily imply that PRP treatment in fCAs is less effective. Thus, these cytokine levels should be checked before PRP therapy.

Characterization of Leukocyte- and Platelet-Rich Plasma Derived from Female Collage Athletes: A Cross-Sectional Cohort Study Focusing on Growth Factor, Inflammatory Cytokines, and Anti-Inflammatory Cytokine Levels

Platelet-rich plasma (PRP) has been increasingly used in sports medicine owing to its various advantages. The purpose of our project was to standardize the parameters before performing large-scale clinical trials in the near future to precisely evaluate individual PRP quality. To examine the effects of regular exercise on PRP quality, this study focused on young female athletes, who have been relatively less studied. Blood samples were obtained from female college athletes (n = 35) and ordinary healthy adults (n = 30), which were considered as controls, and leukocyte-rich PRP (L-PRP) was prepared manually. Body composition indices were determined using a bathroom weight scale equipped with an impedance meter. Growth factors and cytokines were quantified using ELISA kits. Platelet-derived growth factor-BB (PDGF-BB) and Transforming-growth factors β1 (TGFβ1) levels (per platelet) in L-PRP were significantly lower in female athletes than in controls. In contrast, Interleukin-1β and Interleukin 1 receptor antagonist (IL-1RA) levels (per platelet and L-PRP) in L-PRP were significantly higher in athletes, and this difference was more prominent in IL-1RA. These findings suggest that L-PRP from athletes may facilitate the inflammatory phase of the healing process by regulating the pro-inflammatory and anti-inflammatory balance. These chemical compositions can be adopted as "must-check" parameters to characterize individual PRP preparations prior to clinical trials.