Evidence-based indications of platelet-rich plasma therapy

The growth factor content as an indicator of platelet counts in platelet-rich plasma

BACKGROUND

Platelet contains growth factors that enhance tissue repair mechanisms, including epidermal growth factor (EGF), platelet-derived growth factor (PDGF-AA and -AB), and transforming growth factor (TGF)-β. Autologous platelet-rich plasma (PRP) has been shown to significantly improve the treatment of tendon injuries compared with hyaluronic acid and placebo. The topic of agreement between platelet concentrations and growth factors has been covered in some previous studies, but growth factor levels did not correlate well with platelet concentrations.

METHOD

In this study, autologous PRP was prepared by concentrating platelets through a J6-MI centrifuge. The automatic hematology analyzer Sysmex XN-20 was used to analyze the platelet concentration in PRP, and the PRP growth factors were determined by ELISA, including PDGF, transforming growth factor- β1 (TGF-β1), and EGF. Statistical analysis was conducted on data from 107 patients who received autologous PRP using Pearson correlation analysis.

RESULTS

Pearson correlation analysis revealed PDGF, TGF, and EGF had a strong positive correlation with the platelet concentration of the final PRP product (r = 0.697, p < 0.0001; r = 0.488, p < 0.0001; r = 0.572, p < 0.0001, respectively) CONCLUSIONS: There was a strong positive correlation between the concentration of platelets in the final PRP product and the levels of PDGF-AB, TGF-β, and EGF. These results suggested straightforward and cost-effective growth factor tests can provide valuable information about platelet content in PRP.

The efficacy of platelet rich plasma in the treatment of erectile dysfunction: a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Erectile dysfunction (ED) is a common issue among males, and the use of platelet-rich plasma (PRP) therapy for treating ED has gained increasing attention, but there is still no conclusive evidence regarding its efficacy.

AIM

To evaluate the efficacy of PRP therapy for ED.

METHODS

We systematically searched PubMed, Embase, Cochrane Library, and Web of Science databases up to November 2023 to identify randomized controlled trials (RCTs) on PRP therapy for ED. We used Review Manager version 5.4 for data analysis and management.

RESULT

After applying inclusion and exclusion criteria for screening, a total of 4 studies involving 413 patients were finally included in our meta-analysis. According to our analysis, the PRP group showed significant advantages over the placebo group in terms of MCID at the first month (p = 0.03) and sixth months (p = 0.008), while there was no significant difference between the two groups at the third month (p = 0.19). Additionally, in terms of IIEF, PRP showed significantly better efficacy than placebo at the first, third, and sixth months (p < 0.00001).

CONCLUSIONS

PRP shows more effectiveness in treating ED compared to placebo, offering hope as a potential alternative treatment for ED.

Autologous platelet rich plasma injection can be effective in the management of osteoarthritis of the knee: impact on IL-1 β, TNF-α, hs-CRP

OBJECTIVE

To analyze the clinical efficacy of autologous platelet rich plasma (PRP) injection in the treatment of knee osteoarthritis (KOA) and its influence on related biomarkers such as interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), and high-sensitivity C-reactive protein (hs-CRP).

METHOD

150 study subjects are randomly selected from KOA patients received treatment in the Third Hospital of Bethune Hospital from January 2022 to January 2023. After enrollment, patients are randomly numbered 1-100. 75 patients with odd and even numbers are included in the control group and the observation group, respectively. The former is cured with etocoxib, while the latter is treated with autologous PRP injection based on this. The clinical efficacy, relevant biomarkers (IL-1β, TNF-α, hs-CRP), and Lysholm knee score scale and Fugl Meyer assessment (FMA) scores are compared and analyzed.

RESULTS

The total effective rate of 94.67% (71/75) in the observation group was higher than 84.00% (63/75) in the other one group (P < 0.05). Before treatment, the comparison in IL-1β, TNF-α, hs-CRP, Lysholm knee joint score, and FMA scale score are with P > 0.05. When the treatment period is at 1 and 2 months, the IL-1β, TNF-α, hs-CRP levels within the group were lower than before treatment, while the Lysholm knee joint score and FMA scale score were higher than before treatment (P < 0.05). When the treatment period is at 1 and 2 months, the IL-1β, TNF-α, hs-CRP levels and the Lysholm knee joint and FMA scale scores in the observation group were lower and higher than those in the other one group, respectively (P < 0.05).

CONCLUSION

The application of autologous PRP injection therapy in KOA patients can significantly improve their levels of related biomarkers, effectively improve knee joint function and motor function, and have good clinical efficacy.

Clinical efficacy of intracavernous injection of platelet lysate for erectile dysfunction

BACKGROUND

Among the emerging treatments for erectile dysfunction (ED), platelet-rich plasma (PRP), known for its ability to enhance tissue repair and regeneration, stands out as a promising therapeutic approach. In this innovative study, we aimed to assess the efficacy of intracavernous injections of platelet lysate (PL), a derivative of PRP, in improving erectile function among ED patients.

METHODS

We enrolled twenty-six patients, aged between 35 and 70 years (mean age 51.6 ± 11.3 years), who had been experiencing ED for over six months and had an International Index of Erectile Function-5 (IIEF-5) score of 21 or less. Participants received autologous PL injections intracavernously every two weeks for a total of five administrations. We assessed Erection Hardness Score (EHS) and International Index of Erectile Function-5 (IIEF-5) bi-weekly for 16 weeks and conducted penile Doppler ultrasounds pre- and post-treatment to record peak systolic velocity (PSV) and resistance index (RI).

RESULTS

Before treatment, the mean EHS was 2.15 ± 0.88 and IIEF-5 was 10.92 ± 5.28. Remarkable improvements were observed post-treatment, with the EHS significantly increasing to 3.15 ± 0.83 (p < 0.05) and IIEF-5 to 17.23 ± 5.26 (p < 0.05). Penile Doppler ultrasound exhibited an increase in both PSV and RI post-treatment, with the rise in RI being statistically significant.

CONCLUSIONS

Our findings indicate that intracavernous injections of PL substantially enhance erectile function, as evidenced by improvements in EHS, IIEF-5, and the RI of penile Doppler ultrasound, without hemorrhagic events or other adverse reactions apart from temporary pain at the injection site during the 16-week follow-up period. These encouraging results suggest that PL injections are a safe and effective treatment modality for patients with moderate ED, potentially providing a less invasive and more physiologically friendly alternative to current ED management strategies.

TRIAL REGISTRATION

The study received approval from the Institutional Review Board of National Taiwan University Hospital (IRB Number 202008061RIPC, date of registration 08/28/2020).

The role of fibrinogen combined with platelet-rich plasma in enhancing microfracture for cartilage damage: a retrospective study of 113 patients with knee osteoarthritis

OBJECTIVE

Knee osteoarthritis is the most common osteoarthritis and imposes a significant burden on patients' lives. Several treatment methods can promote cartilage repair to varying extents, but there are limited studies on the combined application of different treatments. The purpose of this study is to evaluate the clinical efficacy of microfracture combined with fibrinogen and platelet-rich plasma (PRP) under arthroscopic in treating knee osteoarthritis, so as to provide a basis for clinical treatment decisions.

METHOD

A total of 113 patients with knee osteoarthritis who received orthopedic treatment from January 2021 to June 2022 were selected. They were divided into two groups according to whether they received fibrinogen and PRP treatment in addition to microfracture treatment. The two groups were analyzed to compare the differences in knee joint function and quality of life at different points.

RESULTS

The study compared changes in knee joint function scores and quality of life between the two groups after treatment and found that the quality of life of patients in the combined treatment group was significantly better than that of patients who received microfracture only (at 12-month follow-up, EuroQol-VAS scores were 64.32 ± 5.63 for the microfracture group (MFx) and 75.65 ± 8.57 for the fibrinogen combined with platelet-rich plasma-assisted microfracture group (FPRPA MFx); P = 0.015; at 24-month follow-up, EuroQol-VAS scores were 66.47 ± 5.18 for the MFx group and 79.40 ± 7.43 for the FPRPA MFx group, P = 0.022). There was also a strong correlation between patients' quality of life and knee joint function score index (IKDC score correlation coefficient r=-0.375, Lysholm score correlation coefficient r = 0.497, MOCART score correlation coefficient r = 0.579, VAS score correlation coefficient r = 0.242, T2 value correlation coefficient r=-0.293, P < 0.001). Age-stratified analysis of the patients in the microfracture combined with fibrinogen platelet-rich plasma treatment group showed that the effect of the combined treatment was more pronounced in elderly patients.

CONCLUSIONS

The results of the study showed that compared with microfracture alone, microfracture combined with fibrinogen platelet-rich plasma therapy can further improve patients' knee joint-related function and their quality of life after treatment. The improvement was more obvious in elderly patients.

The Effect of Platelet Fibrin Plasma (PFP) on Postoperative Refractory Wounds: Physiologically Concentrated Platelet Plasma in Wound Repair

OBJECTIVE

Surgical wounds that can't complete primary healing three weeks after surgery are called postoperative refractory wounds. Postoperative refractory wounds would bring great physical and life burdens to the patients and seriously affect their quality of life. To investigate the effect of platelet fibrin plasma (PFP) on postoperative refractory wound healing.

APPROACH

The composition of PFP was analyzed using blood routine and blood biochemicals. Clinical data were collected that met the inclusion criteria after treatment with PFP, and the efficacy of PFP was evaluated by wound healing rate and days to healing. Next, growth factor content in PFP, PRP, and PPP was analyzed using ELISA, and PFP-treated cells were applied to investigate the effect of PFP on fibroblast and endothelial cell function.

RESULTS

PFP component analysis revealed no statistical difference between platelet concentration in PFP and physiological concentration. Clinical statistics showed that PFP treatment was effective in the postoperative refractory wound (four-week wound healing rate > 90%), significantly better than continuous wound dressing. Meanwhile, our result also proved that PFP treatment significantly enhanced vascularization by upregulated the expression level of CD31 and improved granulation tissue thickness. Activated PFP, PRP, and PPP could continuously release growth factors in vitro and the amount of growth factors released by PRP and PFP was significantly higher than PPP. In vitro studies demonstrated that active PFP could improve cell proliferation, migration, adhesion, and angiogenesis in fibroblasts and endothelial cells.

INNOVATION

Physiologically concentrated platelet plasma promoted wound healing and improved related cellular functions. The modified PFP (responsible for accelerating wound healing and enhancing the migration and proliferation of fibroblasts and endothelial cells) was prepared and analyzed for its clinical effectiveness in postoperative refractory wounds.

CONCLUSION

Physiologically concentrated platelet plasma promoted wound healing and improved related cellular functions. The preparation of PFP could significantly reduce the amount of prepared blood, with a good application value for postoperative wounds. PFP can be considered a treatment option, especially for postoperative refractory wounds.

Harmony in Healing: Investigating Platelet-Rich Plasma Activation during Acetylsalicylic Acid Treatment

Platelet-rich plasma (PRP) therapy holds promise for treating various clinical conditions. The activation process is crucial in releasing growth factors and cytokines from platelets, enhancing the therapeutic properties of PRP. Standard activation methods involve autologous thrombin or collagen, with variations in efficacy and growth factor release. This study explores the impact of acetylsalicylic acid (ASA), a commonly used antiplatelet drug, on PRP activation. The results indicate that non-activated PRP extracted from the whole blood of ASA-treated patients exhibits increased inflammatory cytokine concentrations, notably TNFa. After activation with autologous thrombin/CaCl2 or collagen IV, the measured fluorescence intensities suggest varying release patterns between treated and non-treated groups. Understanding the influence of ASA on platelet activation holds implications for personalized medicine and optimizing outcomes for individual patients undergoing PRP therapy. This research sheds light on the potential challenges associated with using antiplatelet drugs, emphasizing the need for careful consideration in tailoring PRP-based regenerative therapies.

Current advances in the treatment of myofascial pain syndrome with trigger point injections: A review

Myofascial pain syndrome (MPS) caused by trigger points in muscles is a common cause of local or generalized pain, which is clinically common, has a high incidence, and has no specific cure. The most popular and widely used clinical method mainly targets the trigger point for treatment, i.e. trigger point injection (TPI) therapy. The injectable drugs mainly include glucose, saline, local anesthetics, botulinum toxin type A, platelet-rich plasma, platelet-poor plasma, steroid preparations, etc. This method is low cost and less invasive, and early clinical applications have shown good efficacy. In this paper, we have reviewed clinical research progress in treating MPS with TPI therapy.

EuroGuiderm guideline on lichen sclerosus-Treatment of lichen sclerosus

INTRODUCTION

Lichen sclerosus (LS) is an inflammatory skin disease affecting all ages. LS typically involves the anogenital site where it causes itching and soreness; it may lead to sexual and urinary dysfunction in females and males; however, it may be asymptomatic. First signs of LS are usually a whitening of the genital skin, sometimes preceded by redness and oedema; fissuring, scarring, shrinkage and fusion of structures may follow in its course. LS is associated with an increased risk of genital cancer. LS has a huge impact on the quality of life of affected patients, and it is important to raise more awareness of this not uncommon disease in order to diagnose and treat it early.

OBJECTIVES

The guideline intends to provide guidance on the diagnostic of LS (part 1), highlight important aspects in the care of LS patients, generate recommendations and treatment algorithms (part 2) on topical, interventional and surgical therapy, based on the latest evidence, provide guidance in the management of LS patients during pregnancy, provide guidance for the follow-up of patients with LS and inform about new developments and potential research aspects.

MATERIALS AND METHODS

The guideline was developed in accordance with the EuroGuiDerm Methods Manual v1.3 https://www.edf.one/de/home/Guidelines/EDF-EuroGuiDerm.html. The wording of the recommendations was standardized (as suggested by the GRADE Working Group). The guideline development group is comprised of 34 experts from 16 countries, including 5 patient representatives.

RESULTS

Ultrapotent or potent topical corticosteroids in females and males, adults and children remain gold standard of care for genital LS; co-treatment with emollients is recommended. If standard treatment fails in males, a surgical intervention is recommended, complete circumcision may cure LS in males. UV light treatment is recommended for extragenital LS; however, there is limited scientific evidence. Topical calcineurin inhibitors are second line treatment. Laser treatment, using various wave lengths, is under investigation, and it can currently not be recommended for the treatment of LS. Treatment with biologics is only reported in single cases.

CONCLUSIONS

LS has to be diagnosed and treated as early as possible in order to minimize sequelae like scarring and cancer development. Topical potent and ultrapotent corticosteroids are the gold standard of care; genital LS is often a lifelong disease and needs to be treated long-term.

Effect of extracorporeal shock wave combined with autologous platelet-rich plasma injection on rotator cuff calcific tendinitis: study protocol for a randomized controlled trial

BACKGROUND

Rotator cuff calcific tendinitis (RCCT) is a common shoulder disease whose main symptoms include shoulder pain, limited mobility, and calcification deposits in the shoulder. Traditional treatment methods have certain limitations, so finding new treatment methods has become the focus of research. Extracorporeal shock wave (ESW) and platelet-rich plasma (PRP) treatments have attracted much attention due to their non-invasive and tissue repair-promoting properties; however, the efficacy of their combined treatment in RCCT remains unclear.

METHODS

This study is designed as a single-center, assessment-blind, randomized controlled clinical trial with three parallel groups. Sixty subjects will be recruited and randomly divided into the ESW group, PRP group, and ESW combined with PRP group, in a 1:1:1 ratio. The entire intervention period is 4 weeks, and the follow-up period is 4 weeks. Outcomes will be measured at baseline (T0), after 1 week of intervention (T1), after 2 weeks of intervention (T2), after 4 weeks of intervention (T3), and after an additional 4 weeks of follow-up period (T4). The primary endpoint is the VAS score. Secondary endpoints are ASES, CMS, UCLA, and the location and size of calcified areas.

DISCUSSION

This study aims to evaluate the efficacy of ESW therapy combined with PRP in treating RCCT. We compare the effects of single and combined treatments to explore their impact on disease symptoms, functional improvement, and calcification regression. This provides a scientific basis for identifying more effective treatment options.

TRIAL REGISTRATION

ClinicalTrials.gov NCT06372600. Registered on April 17, 2024; version 1.

The impact of plasma-rich platelet injection to perianal sphincters on incontinence and quality of life in patients with rectal cancer after low anterior or intersphincteric resection: a prospective cohort study

BACKGROUND

Incontinence is not rare after rectal cancer surgery. Platelet-rich plasma may promote tissue repair and generation but has never been tested for the treatment of anal incontinence. This study evaluated the impact of platelet-rich plasma injection on the severity of incontinence and quality of life after low rectal cancer surgery.

METHODS

This is a prospective cohort proof of concept study in a colorectal cancer institution. Patients had undergone low anterior or intersphincteric resection for low rectal cancer and had a Wexner score > 4. Ten milliliters of platelet-rich plasma were injected into the internal and external sphincters under endoanal ultrasound (EAUS) guidance. Primary outcome measure was > 2 point improvement in Wexner score (improved group). The patients were assessed with endo-anal ultrasound examination, manometry, the Wexner Questionnaire and SF-36 Health Surveys, and patients were asked whether they used pads and antidiarrheal medications before and 6 months after PRP injection.

RESULTS

Of 20 patients included in the study, 14 (70%) were men, and the average age was 56.8 (SD = 9.5) years. No statistically significant difference was found in Wexner scores before and after PRP injection (p = 0.66). Seven (35%) patients experienced a > 2 point improvement in Wexner score. Rectal manometry demonstrated improved squeezing pressure (p = 0.0096). Furthermore, physical functioning scoring (p = 0.023), role limitation (p = 0.016), emotional well-being (p = 0.0057) and social functioning (p = 0.043) domains on the SF-36 questionnaire improved. One (5%) and three (15%) patients stopped using pads and antidiarrheal medications.

CONCLUSION

Platelet-rich plasma injection does not restore Wexner scores, but more than one-third of patients may benefit from this application with an improvement of > 2 points in their scores. Platelet-rich plasma injection may improve squeezing pressure and certain life quality measures for incontinent patients after rectal cancer surgery.

Platelet-Rich Therapies in Hernia Repair: A Comprehensive Review of the Impact of Platelet Concentrates on Mesh Integration in Hernia Management

Mesh-augmented hernia repair is the gold standard in abdominal wall and hiatal/diaphragmatic hernia management and ranks among the most common procedures performed by general surgeons. However, it is associated with a series of drawbacks, including recurrence, mesh infection, and adhesion formation. To address these weaknesses, numerous biomaterials have been investigated for mesh coating. Platelet-rich plasma (PRP) is an autologous agent that promotes tissue healing through numerous cytokines and growth factors. In addition, many reports highlight its contribution to better integration of different types of coated meshes, compared to conventional uncoated meshes. The use of PRP-coated meshes for hernia repair has been reported in the literature, but a review of technical aspects and outcomes is missing. The aim of this comprehensive review is to report the experimental studies investigating the synergistic use of PRP and mesh implants in hernia animal models. A comprehensive literature search was conducted across PubMed/Medline, Web of Science, and Scopus without chronological constraints. In total, fourteen experimental and three clinical studies have been included. Among experimental trials, synthetic, biologic, and composite meshes were used in four, nine, and one study, respectively. In synthetic meshes, PRP-coating leads to increased antioxidant levels and collaged deposition, reduced oxidative stress, and improved inflammatory response, while studies on biological meshes revealed increased neovascularization and tissue integration, reduced inflammation, adhesion severity, and mechanical failure rates. Finally, PRP-coating of composite meshes results in reduced adhesions and improved mechanical strength. Despite the abundance of preclinical data, there is a scarcity of clinical studies, mainly due to the absence of an established protocol regarding PRP preparation and application. To this point in time, PRP has been used as a coating agent for the repair of abdominal and diaphragmatic hernias, as well as for mesh fixation. Clinical application of conclusions drawn from experimental studies may lead to improved results in hernia repair.

The Biological Effect of Platelet-Rich Plasma on Rotator Cuff Tears: A Prospective Randomized In Vivo Study

The positive effect of platelet-rich plasma (PRP) on tendon metabolism has been extensively investigated and proven in vitro. Additionally, in vivo animal studies have correlated the application of PRP with the enhancement of tenocyte anabolic activity in the setting of tendon degeneration. However, less is known about its in vivo effect on human tendon biology. The purpose of the current prospective randomized comparative study was to evaluate the effect of PRP on torn human supraspinatus tendon. Twenty consecutive eligible patients with painful and magnetic resonance imaging (MRI)-confirmed degenerative supraspinatus tendon tears were randomized in a one-to-one ratio into two groups. The patients in the experimental group (n = 10) underwent an ultrasound-guided autologous PRP injection in the subacromial space 6 weeks before the scheduled operation. In the control group (n = 10), no injection was made prior to surgery. Supraspinatus tendon specimens were harvested from the lateral end of the torn tendon during shoulder arthroscopy and were evaluated under optical and electron microscopy. In the control group, a mixed cell population of oval and rounded tenocytes within disorganized collagen and sites of accumulated inflammatory cells was detected. In contrast, the experimental group yielded abundant oval-shaped cells with multiple cytoplasmic processes within mainly parallel collagen fibers and less marked inflammation, simulating the intact tendon structure. These findings indicate that PRP can induce microscopic changes in the ruptured tendon by stimulating the healing process and can facilitate a more effective recovery.

Role of orthobiologics in managing patellar tendinopathy: A narrative review

Patellar tendinopathy is a relatively common cause of anterior knee pain in athletes. It is predominantly seen in sports involving jumping, running, abrupt change in direction like basketball, volleyball, soccer, sprinting and jumping. The main pathophysiology is considered to be repetitive microtrauma at the inferior pole of patella along with a poor healing response. Although eccentric exercises have shown to be beneficial, the improvement is often slow and may result in a less than satisfactory outcome. There is a growing interest of orthobiologics, mainly platelet-rich plasma (PRP) in multiple chronic musculoskeletal pathologies. This narrative review aimed to analyse the current evidence on the role of orthobiologics in the management of recalcitrant patellar tendinopathy. Multiple studies have shown significant clinical improvement with negligible adverse effects on PRP injection for patellar tendinopathy. Most studies assessed report that the effects of PRP are sustained. However, among all studies evaluated, there is a considerable heterogeneity in terms of PRP composition, number of injections, dosage interval and postinjection rehabilitation protocol, pointing to the need for further research to enable standardisation of PRP therapy. Stem cells too have shown potential to be effective as a treatment modality for chronic patellar tendinopathy, but there is limited data to recommend its use outside of research setting or to enable a meaningful comparison to PRP. There is a promising role of orthobiologics in management of chronic patellar tendinopathy not responding to conventional treatment.

Level of Evidence

Not applicable (narrative review).

Arthroscopic Surgery Combined With Platelet-Rich Plasma Does Not Significantly Improve Pain, Function, Complications, and Retear Rate Compared With Arthroscopic Surgery Alone for Full-Thickness Rotator Cuff Tears: A Systematic Review and Meta-analysis

PURPOSE

To evaluate the effectiveness and safety of arthroscopic surgery combined with platelet-rich plasma (PRP) compared with arthroscopic surgery alone in the treatment of patients with full-thickness rotator cuff tears.

METHODS

The Cochrane Library, PubMed, Embase, Scopus, EBSCO, Web of Science, China National Knowledge Infrastructure, and Wanfang Database were systematically searched from inception to November 2023. Subject words combined with free words were used to collect randomized controlled trials focusing on arthroscopic surgery combined with PRP in the treatment of full-thickness rotator cuff tears. The assessment of evidence quality employed the Cochrane Collaboration risk of bias tool, and data analysis was performed using RevMan 5.3 software.

RESULTS

A total of 9 studies with 537 patients were included. The meta-analysis revealed that compared with the arthroscopic surgery alone group, the summary result of University of California Los Angeles score scores in the arthroscopic combined with PRP group was (mean difference [MD] = 1.08, 95% confidence interval [CI] 0.19∼1.97, P = .02), subgroup analysis of surgical suture method visual analog scale (VAS) single-row (MD = -1.00, 95% CI -1.50 to -0.50, P < .0001), VAS double-row (MD = -0.10, 95% CI -0.17 to -0.02, P = .02), and Constant-Murley score single-row (MD = 3.49, 95% CI 0.32∼6.66, P = .03), the difference was statistically significant, and the differences in VAS, Constant-Murley score, and Quick Disabilities of the Arm, Shoulder and Hand, complications, and retear rate were not statistically significant.

CONCLUSIONS

Patients undergoing arthroscopic repair combined with PRP treatment showed no difference in pain, function, complications, and retear rate compared with those treated with arthroscopic surgery alone.

LEVEL OF EVIDENCE

Level II, systematic review and meta-analysis of Level I and II evidence.

Surgical Interventions for the Management of Obesity-Related Joint Pain: A Narrative Review

Obesity-related joint pain is a common and debilitating condition that significantly impacts the quality of life, primarily due to the excess weight straining the joints. This results in inflammation and degeneration, which can cause pain, stiffness, and difficulty moving. We aimed to comprehensively review the literature discussing surgical interventions for obesity-related joint pain. We searched across databases (PubMed, Scopus, and Cochrane Library) to identify studies published between 2000 and 2023 that assessed surgical interventions for obesity-related joint pain. This review highlights the complex interplay of mechanical, inflammatory, and metabolic factors contributing to joint pain in obese individuals, highlighting both surgical and non-surgical interventions. Non-surgical interventions include weight loss, exercise, physical therapy, and medications. Surgical interventions include bariatric surgery and joint replacement surgery. Bariatric surgery significantly reduces body weight and improves the quality of life outcomes; however, multiple studies have found no improvement or worsening of joint pain post-surgery. Total joint arthroplasty has demonstrated good improvement in pain and function outcomes based on recent meta-analyses, although risks of complications are higher in obese patients. The treatment choice for obesity-related joint pain depends on the individual patient's circumstances. Non-surgical interventions are usually the first line of treatment. However, if these interventions are not effective, surgical interventions may be an option.

Towards optimized tissue regeneration: a new 3D printable bioink of alginate/cellulose hydrogel loaded with thrombocyte concentrate

Introduction

Autologous platelet concentrate (APC) are pro-angiogenic and can promote wound healing and tissue repair, also in combination with other biomaterials. However, challenging defect situations remain demanding. 3D bioprinting of an APC based bioink encapsulated in a hydrogel could overcome this limitation with enhanced physio-mechanical interface, growth factor retention/secretion and defect-personalized shape to ultimately enhance regeneration.

Methods

This study used extrusion-based bioprinting to create a novel bioink of alginate/cellulose hydrogel loaded with thrombocyte concentrate. Chemico-physical testing exhibited an amorphous structure characterized by high shape fidelity. Cytotoxicity assay and incubation of human osteogenic sarcoma cells (SaOs2) exposed excellent biocompatibility. enzyme-linked immunosorbent assay analysis confirmed pro-angiogenic growth factor release of the printed constructs, and co-incubation with HUVECS displayed proper cell viability and proliferation. Chorioallantoic membrane (CAM) assay explored the pro-angiogenic potential of the prints in vivo. Detailed proteome and secretome analysis revealed a substantial amount and homologous presence of pro-angiogenic proteins in the 3D construct.

Results

This study demonstrated a 3D bioprinting approach to fabricate a novel bioink of alginate/cellulose hydrogel loaded with thrombocyte concentrate with high shape fidelity, biocompatibility, and substantial pro-angiogenic properties.

Conclusion

This approach may be suitable for challenging physiological and anatomical defect situations when translated into clinical use.

Postinjection protocols following platelet-rich plasma administration for knee osteoarthritis: A systematic review

OBJECTIVE

Platelet-rich plasma (PRP) use in treating orthopedic conditions has increased, yet evidence of its clinical efficacy is inconsistent and limited by heterogeneity in osteoarthritis (OA) severity, PRP preparations and protocols, and clinical outcome measurement. This review aims to characterize the variations in postinjection protocols in studies assessing the clinical efficacy of PRP for knee OA.

LITERATURE SURVEY

A systematic review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A literature search from database inception to February 2023 of CINAHL, MEDLINE, and EMBASE was conducted.

METHODOLOGY

Article screening, data extraction, and risk of bias assessments were completed in duplicate by two reviewers. Primary outcomes were presence/absence and timing of the following postinjection protocol components: nonsteroidal anti-inflammatory drug (NSAID) restrictions, non-NSAID analgesic and cryotherapy use, immediate knee flexion/extension, immediate rest, activity restriction, return-to-activity guidelines, and rehabilitation protocols. A descriptive analysis was used to analyze the data. Given study heterogeneity, a meta-analysis was not performed.

SYNTHESIS

A total of 187 studies were included for analysis. Half of all studies (51.9%) excluded patients due to preinjection NSAID use, most often within 5 days of blood sampling or injection. Postinjection NSAID restriction was included in 42.8% of studies, ranging from 1 to 1800 days. Few studies (19.4%) that permitted non-NSAID analgesia restricted their use prior to clinical assessments. Postinjection immediate flexion, extension, and immobilization were rarely (8.6%) mentioned. Activity restriction was included in a third of studies (35.3%), with the most frequent length of restriction being 1 day. Postinjection return-to-activity protocols were less common (20.3%), usually with a "gradual" and/or "as tolerated" recommendation. A minority of studies (16.0%) reported physical therapy protocols and the vast majority (93.3%) were home based.

CONCLUSION

Significant heterogeneity remains in post-PRP injection protocols, with unclear consensus regarding optimal recommendations and limited rationale for the protocols outlined. Further study is necessary to compare protocols directly and to determine which pre- and postinjection recommendations can result in optimal outcomes.

Return to Sport After Ulnar Collateral Ligament Tears Treated with Platelet-Rich Plasma Injections is Influenced by Length of Rehabilitation and Leukocyte Content of Injections: A Systematic Review

PURPOSE

To analyze the current literature assessing return to sport (RTS) outcomes after platelet-rich plasma (PRP) injections for the nonoperative treatment of ulnar collateral ligament (UCL) injuries.

METHODS

A systematic review of PubMed, Embase, and Web of Science databases was conducted in June 2023 to identify studies assessing RTS after PRP injections for UCL injuries. Tear severity, leukocyte content of PRP, rehabilitation protocol, and RTS outcomes were collected. Heterogeneity was assessed through proportional random-effects models for RTS and return to preinjury level of play (RTLP) with subgroup analysis by rehabilitation length, leukocyte content of PRP, and tear severity.

RESULTS

Eight studies with 278 partial-thickness and 44 full-thickness tears were identified. The mean age of patients ranged from 17.3 to 26 years. The mean RTS time after injection ranged from 5.2 to 25.4 weeks. High heterogeneity was observed among studies, with RTS rates ranging from 46% to 100% (I2 = 83%) and RTLP rates ranging from 34% to 100% (I2 = 83%). Studies with the longest rehabilitation programs (12-14 weeks) had RTS rates of 87% to 100% (I2 = 0%). RTS rates among athletes treated with leukocyte-poor and leukocyte-rich PRP ranged from 73% to 100% (I2 = 30%) and 52% to 88% (I2 = 84%), respectively. Subanalysis of RTS by tear severity demonstrated high variability, with partial-thickness rates ranging from 59% to 100% (I2 = 55%) and full-thickness rates ranging from 27% to 100% (I2 = 63.2%).

CONCLUSIONS

Studies assessing RTS after PRP injections are highly heterogeneous; however, current data suggest nonoperative RTS and RTLP rates ranging from 46% to 100% and 34% to 100%, respectively. Studies with at least 12 weeks of rehabilitation and studies using leukocyte-poor PRP demonstrated low heterogeneity and greater RTS rates. Alternatively, high heterogeneity was observed among both partial- and full-thickness tears.

LEVEL OF EVIDENCE

Level IV, systematic review of Level III-IV studies.

Long term improvement of knee osteoarthritis after injection of single high/very high volume of very pure PRP: A retrospective analysis of patients optimally managed in dedicated centers

Introduction

PRP is gaining increasing interest for pain relief and improvement of joint function in patients with knee osteoarthritis (KOA) but practices and results remain heterogeneous limiting its adoption as standard of care. Current international recommendations are to collect real-life evidence of efficacy with a systematic monitoring of PRP quality and patients' outcomes. We aimed to analyze the response of patients presenting KOA and treated with standardized PRP injection in routine care. We also investigated the potential contributing factors including patient's phenotype and PRP characteristics.

Methods

Patients with symptomatic KOA and that failed first-line therapy received a single injection of a qualified PRP prepared using medical devices allowing to recover a high/very high volume of very pure PRP. Visual analogue scale (VAS) and Western Ontario and McMaster Osteoarthritis Index (WOMAC) score were recorded at baseline and during 18 months follow-up.

Results

431 patients had available follow-up data at 3 months, 291 at 6 months, 137 at 12 months and 44 at 18 months. PRP induced a significant decrease of WOMAC score at all follow up endpoints (29.2 ± 19.2 at 3 months, p < 0.001 and 25.9 ± 19.7 at 12 months, p < 0.01, compared to 39.7 ± 18.9 at baseline). Similar results were observed for pain VAS (38.9 ± 23.3 at 3 months, p < 0.001 and 35.3 ± 24.1 at 12 months, p < 0.05, compared to 56.0 ± 20.7 at baseline). Changes at 12 months were correlated to baseline scores and to the level of improvement at 3 months. The proportion of OMERACT OARSI responders reached 56.2 % for the total cohort and 60.4 % for severe patients at 6 months. Treatment failure occurred for 8.4 % of patients. Age, BMI or Kellgren-Lawrence grade did not impact on efficacy.

Conclusion

This real-life study evidences the clinical benefit of a standardized high or very high-volume injection of very pure PRP in patients with KOA, including those with a severe grade. It opens perspectives in the positioning of such strategy to delay arthroplasty and provide insights on factors able to anticipate long term efficacy.

Method to obtain a plasma rich in platelet- and plasma-growth factors based on water evaporation

Platelet-Rich Plasma, also known as PRP, is an autologous biologic product used in medicine as a treatment for tissue repair. Nowadays, the majority of PRP obtention methods enrich only platelets, not considering extraplatelet biomolecules, which take part in several cell processes. In the present work, a novel PRP preparation method was developed to obtain a PRP rich in both platelet and plasma extraplatelet molecules. The method is based on the evaporation of the water of the plasma using a rotary evaporator. With this new methodology an increase in plasmatic growth factors and, as a consequence, a better dermal fibroblast cell viability was achieved, compared to a standard PRP formulation. This novel PRP product obtained with this new methodology showed promising results in vitro as an improved PRP treatment in future application.

Effects of injectable platelet-rich fibrin (i-PRF) on pterygium surgery with conjunctival autograft

OBJECTIVES

To investigate the effects of subconjunctival injectable platelet-rich fibrin (i-PRF) injection on healing and complication rates after pterygium surgery with conjunctival autograft.

METHODS

This retrospective and comparative study evaluated 31 eyes that received i-PRF injections under the donor and graft conjunctiva following pterygium surgery, while 34 eyes did not receive i-PRF after the pterygium surgery. The patients' follow-up period was for 12 months. Postoperative recurrence, epithelial healing time, postoperative pain score, graft edema, and sliding of the graft (need for re-suturation) data were evaluated.

RESULTS

For the 12 months after surgery, one eye (3.2%) in the i-PRF group had developed corneal recurrence, and five eyes (14.7%) in the non-i-PRF group had developed recurrence. The mean corneal epithelial healing time was 2.96 ± 0.70 days in the i-PRF group and 3.58 ± 0.70 days in the non-i-PRF group (p = 0.001). The mean healing time of the donor conjunctiva epithelium was 3.84 ± 0.70 days in the i-PRF group, whereas it was 4.44 ± 0.74 days in the non-i-PRF group (p = 0.006). The mean postoperative pain score was 4.45 ± 1.52 in the i-PRF group and 5.08 ± 1.40 in the non-i-PRF group. In the non-i-PRF group, three cases (8.8%) required re-suturation, whereas, in the i-PRF group, no one required re-suturation.

CONCLUSIONS

Thanks to its platelets-derived growth factors, i-PRF can be a safe and effective adjuvant therapy for faster healing of conjunctival autograft and in the prevention of recurrence.

Dual Network Hydrogels Based on PRP and SA Promote the Retention Rate and Vascularization of Transplanted Fat

BACKGROUND

Autologous adipose tissue often experiences ischemia and hypoxia after transplantation, leading to low retention rates and unstable operative impacts due to necrotic absorption. Platelet-rich plasma (PRP) can enhance fat regeneration and increase the fat retention rate after transplantation. However, the quick release of growth factors (GFs) in PRP decreases therapeutic efficiency. This study aimed to achieve a slow release of PRP to promote fat retention.

METHODS

We prepared a dual-network hydrogel (DN gel) based on FDA-approved PRP and sodium alginate (SA) through a simple "one-step" activation process. In vivo study, adipose tissue with saline (control group), SA gel (SA gel group), PRP gel (PRP gel group), and DN gel (DN gel group) was injected subcutaneously into the dorsum of nude mice. At 4 and 12 weeks after injection, tissues were assessed for volume and weight. Hematoxylin and eosin staining (HE) and immunofluorescence staining were performed for histological assessment.

RESULTS

DN gel exhibits long-lasting growth factor effects, surpassing conventional clinical PRP gel regarding vascularization potential. In fat transplantation experiments, DN gel demonstrated improved vascularization of transplanted fat and increased retention rates, showing promise for clinical applications.

CONCLUSIONS

DN gel-assisted lipofilling can significantly improve the retention rate and quality of transplanted fat. DN gel-assisted lipofilling, which is considered convenient, is a promising technique to improve neovascularization and fat survival.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Comparison of the Efficacy Between Regional Nerve Block and Ring Block as Local Anesthetic Techniques for Platelet-Rich Plasma Treatment

Introduction Platelet-rich plasma (PRP), a solution of concentrated platelets, has been widely used to promote wound repair and tissue regeneration. In the treatment of pattern hair loss, platelets in PRP secrete an abundance of growth factors, including platelet-derived growth factor (PDGF), fibroblast growth factor(FGF), and many more, which stimulate and increase signaling molecules and accelerate cell proliferation. In the PRP treatment for hair regrowth, the supratrochlear nerve (STN) block and supraorbital nerve (SON) block are given to anesthetize the scalp up to the vertex except for the temporal region. The ring block is the common local anesthetic technique used by infiltrating local anesthetic agents around the target area. The primary objectives were to compare the pain and anesthetic success rates produced by regional nerve blocks and ring blocks. Materials and methods A sample size of 100 patients undergoing PRP treatment for hair regrowth were taken as the subjects for the study. Patients were allotted into two groups by randomization. Group 1 was given regional nerve blocks as the anesthetic technique used for local anesthesia, and group 2 was given ring blocks. In the study group, STN and SON blocks as the regional nerve blocks were given 2% lignocaine with 1:80000 adrenaline to anesthetize the area, and the PRP was injected from the anterior hairline up to the vertex of the scalp, not involving the occipital and temporal regions. In the control group, a ring block was given for the same procedure. Participants from both groups were assessed for the pain and analgesia caused by ring block and regional nerve blocks using the visual analog scale (VAS). Results A mean rank of 30.28 was observed for the regional nerve block technique, and a mean rank of 70.72 was observed for the ring block technique. A p-value of 0.00 that is <0.05 was observed, which shows there is a significant difference in the pain and the analgesia experienced by the subjects between the two groups, during and three hours after the procedure. Conclusion PRP is one of the most commonly used treatments for hair regrowth. The ring block is the common local anesthetic technique used for producing anesthesia, while regional nerve blocks are more effective in producing local anesthesia. This study proves that STN and SON blocks are better anesthetic techniques than the ring block technique for PRP treatment in hair growth.

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 β, 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.

Biomimetic mineralization of platelet lysate/oxidized dextran cryogel as a macroporous 3D composite scaffold for bone repair

Scaffold development approaches using autologous sources for tissue repair are of great importance in obtaining bio-active/-compatible constructs. Platelet-rich plasma (PRP) containing various growth factors and platelet lysate (PL) derived from PRP are autologous products that have the potential to accelerate the tissue repair response by inducing a transient inflammatory event. Considering the regenerative capacity of PRP and PL, PRP/PL-based scaffolds are thought to hold great promise for tissue engineering as a natural source of autologous growth factors and a provider of mechanical support for cells. Here, a bio-mineralized PRP-based scaffold was developed using oxidized dextran (OD) and evaluated for future application in bone tissue engineering. Prepared PL/OD scaffolds were incubated in simulated body fluid (SBF) for 7, 14 and 21 d periods. Mineralized PL/OD scaffolds were characterized using Fourier transform infrared spectroscopy, x-ray diffraction spectroscopy, scanning electron microscopy (SEM), thermogravimetric analysis, porosity and compression tests. SEM and energy-dispersive x-ray spectroscopy analyses revealed mineral accumulation on the PL/OD scaffold as a result of SBF incubation.In vitrocytotoxicity andin vitrohemolysis tests revealed that the scaffolds were non-toxic and hemocompatible. Additionally, human osteoblasts (hOBs) exhibited good attachment and spreading behavior on the scaffolds and maintained their viability throughout the culture period. The alkaline phosphatase activity assay and calcium release results revealed that PL/OD scaffolds preserved the osteogenic properties of hOBs. Overall, findings suggest that mineralized PL/OD scaffold may be a promising scaffold for bone tissue engineering.

Platelet-Rich Plasma for the Treatment of Stress Urinary Incontinence-A Randomized Trial

IMPORTANCE

Urinary incontinence affects millions of women worldwide.

OBJECTIVE

The aim of the current study was to evaluate the efficacy and safety of periurethral platelet-rich plasma (PRP) injections in women with stress urinary incontinence (SUI).

STUDY DESIGN

This was a single-center, double-blind, randomized sham-controlled trial. Fifty participants with SUI and urodynamic stress incontinence were randomized in 2 equally sized groups. Women in the PRP group received 2 PRP injections at 3 levels of the urethra at 4- to 6-week intervals. Women in the sham group were injected with sodium chloride 0.9%. At baseline, participants underwent urodynamic studies and a 1-hour pad test and completed the International Consultation on Incontinence Questionnaire-Female Lower Urinary Tract Symptoms (ICIQ-FLUTS), the Patient Global Impression Scale of Improvement, and the King's Health Questionnaire. At follow-up visits (1, 3, and 6 months), women underwent the 1-hour pad test and completed the King's Health Questionnaire and the ICIQ-FLUTS. Primary outcome was the subjective evaluation as indicated by the response to question 11a of the ICIQ-FLUTS questionnaire. Secondary outcomes included scores of questionnaires and urine loss assessed on the 1-hour pad test. The level of discomfort during injections and any adverse events were also evaluated.

RESULTS

During follow-up, the mean score of the 11a question decreased significantly in the PRP group compared with sham. Subjective cure was significantly higher in the PRP group (32% vs 4%, P < 0.001). A significant reduction of urine loss assessed on the 1-hour pad test was observed in the PRP group compared with the sham group at 6-month follow-up. No adverse events were observed.

CONCLUSIONS

Periurethral PRP injections were superior to sham injections in improving SUI symptoms with an excellent safety profile.

Platelet-rich plasma in orthopedics: Bridging innovation and clinical applications for bone repair

In the burgeoning domain of orthopedic therapeutic research, Platelet-Rich Plasma (PRP) has firmly established its position, transforming paradigms ranging from tissue regeneration to the management of chondral lesions. This review delves into PRP's recent integrations with cutting-edge interventions such as 3D-printed scaffolds, its role in bone and cartilage defect management, and its enhanced efficacy when combined with molecules like Kartogenin (KGN) for fibrocartilage zone repair. Significant attention is paid to tissue engineering for meniscal interventions, where a combination of KGN, PRP, and bone marrow-derived mesenchymal stem cells are under exploration. Within the sphere of osteochondral regenerative therapy, the synergy of PRP with Bone Marrow Aspirate Concentrate (BMAC) represents a noteworthy leap towards cartilage regeneration. The innovative incorporation of PRP with biomaterials like hydroxyapatite and graphene oxide further underscores its versatility in supporting structural integrity and ensuring sustained growth factor release. However, while PRP's autologous and nontoxic nature makes it an inherently safe option, concerns arising from its preparation methods, particularly with bovine thrombin, necessitate caution. As of 2023, despite the burgeoning promise of PRP in bone healing, the quest for its standardization, optimization, and substantiation through rigorous clinical trials continues. This comprehensive review elucidates the contemporary applications, challenges, and future trajectories of PRP in orthopedics, aiming to spotlight areas primed for further research and exploration.

Platelet-Rich Plasma (PRP) in Dermatology: Cellular and Molecular Mechanisms of Action

Platelet-rich plasma (PRP) therapy has gained attention in the scientific field due to its potential regenerative effects and great benefit-risk ratio. This review extensively explores the most studied mechanisms of this therapy according to the etiopathogenesis of skin diseases: cellular proliferation, matrix formation, regulation of inflammation, angiogenesis, collagen synthesis, and the remodeling of new tissue. Moreover, it draws on newly reported and lesser-known effects of PRP: its anti-apoptotic effects, immunological suppression, decrease in melanin synthesis, anti-microbial effects, overexpression of miR-155, antioxidant effects, and their involved pathways. This work aims to provide a complete update for understanding PRP's benefits and clinical relevance in wound healing, alopecia, pigmentary disorders, scars, rejuvenation, lichen sclerosus, and other inflammatory dermatoses, based on the current evidence. Furthermore, recent reports with novel indications for PRP therapy are highlighted, and new potential pathways correlated with the pathogenesis of skin diseases are explored.

The Clinical Application of Platelet-Rich Plasma in the Female Reproductive System: A Narrative Review

Platelet-rich plasma is an autologous plasma containing platelets prepared from fresh whole blood drawn from a peripheral vein. Through processing, it can be prepared to contain supraphysiologic levels of platelets at three to five times greater than the level of normal plasma. PRP has been explored both in vivo and ex vivo in the human endometrium model in its ability to harness the intrinsic regenerative capacity of the endometrium. Intrauterine autologous PRP infusions have been shown to increase endometrial thickness and reduce the rate of intrauterine adhesions. In the setting of recurrent implantation failure, intrauterine infusion of PRP has been shown to increase clinical pregnancy rate. PRP also appears to hold a potential role in select patients with premature ovarian insufficiency, poor ovarian responders and in improving outcomes following frozen-thawed transplantation of autologous ovarian tissue. Further studies are required to explore the potential role of PRP in reproductive medicine further, to help standardise PRP protocols and evaluate which routes of administration are most effective.

Platelet-rich plasma for pilonidal disease: a systematic review

OBJECTIVE

To examine the use of platelet-rich plasma (PRP) for treatment of pilonidal disease (PD) and thus provide a reference for clinical application.

METHODS

A systematic review of PubMed and the Cochrane Library was performed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses. We considered all studies that reported the use of PRP for treatment of PD. Extracted data included the first author's name, year of publication, study type, number of included patients, inclusion and exclusion criteria, interventions, anesthesia, application of PRP (source, preparation, dose, and operation), antibiotics, follow-up time, therapeutic outcomes, and adverse events.

RESULTS

In total, eight randomized controlled trials and one prospective cohort study involving 809 patients were included. PRP reduced pain, accelerated healing, and reduced adverse events. The application of combined minimally invasive surgery achieved better results. However, overfilling of the wound with PRP in minimally invasive surgeries was shown to potentially increase the risk of adverse events.

CONCLUSION

PRP can be used as an adjuvant treatment in PD surgery to improve the therapeutic effect and reduce adverse events. The optimal combination of PRP and various factors is an important direction of future research.INPLASY registration number: INPLASY2023100070.

Platelet-rich plasma for erectile dysfunction: a review of the current research landscape

INTRODUCTION

Erectile dysfunction (ED) is the inability to achieve or maintain erection for satisfactory sexual performance. ED drastically reduces the quality of life for men and their partners and is commonly linked to comorbid conditions such as diabetes and cardiovascular disease. As a result, clinicians and researchers are working to improve treatments for ED. Current guideline-approved ED treatments include oral phosphodiesterase type 5 inhibitors, intraurethral alprostadil, penile intracavernosal injections, and penile prosthesis surgery. Today, there is increasing interest in restorative therapies such as intracavernosal platelet-rich plasma (PRP) for the management of ED.

OBJECTIVES

This narrative review describes the current trials investigating intracavernosal PRP for ED and proposes future directions to increase the strength of evidence to support use of PRP in this population.

METHODS

A comprehensive literature search of PubMed, Science Direct, and Scopus was performed to identify all randomized clinical trials using PRP for the treatment of ED.

RESULTS

We identified 4 randomized clinical trials investigating the safety and efficacy of PRP for ED. We found significant heterogeneity among study protocols, including collection of PRP, dosing of PRP, and follow-up.

CONCLUSION

While intracavernosal PRP is considered safe, its efficacy for the management of ED remains unknown due to variability among clinical trials.

Expanding applications of allogeneic platelets, platelet lysates, and platelet extracellular vesicles in cell therapy, regenerative medicine, and targeted drug delivery

Platelets are small anucleated blood cells primarily known for their vital hemostatic role. Allogeneic platelet concentrates (PCs) collected from healthy donors are an essential cellular product transfused by hospitals to control or prevent bleeding in patients affected by thrombocytopenia or platelet dysfunctions. Platelets fulfill additional essential functions in innate and adaptive immunity and inflammation, as well as in wound-healing and tissue-repair mechanisms. Platelets contain mitochondria, lysosomes, dense granules, and alpha-granules, which collectively are a remarkable reservoir of multiple trophic factors, enzymes, and signaling molecules. In addition, platelets are prone to release in the blood circulation a unique set of extracellular vesicles (p-EVs), which carry a rich biomolecular cargo influential in cell-cell communications. The exceptional functional roles played by platelets and p-EVs explain the recent interest in exploring the use of allogeneic PCs as source material to develop new biotherapies that could address needs in cell therapy, regenerative medicine, and targeted drug delivery. Pooled human platelet lysates (HPLs) can be produced from allogeneic PCs that have reached their expiration date and are no longer suitable for transfusion but remain valuable source materials for other applications. These HPLs can substitute for fetal bovine serum as a clinical grade xeno-free supplement of growth media used in the in vitro expansion of human cells for transplantation purposes. The use of expired allogeneic platelet concentrates has opened the way for small-pool or large-pool allogeneic HPLs and HPL-derived p-EVs as biotherapy for ocular surface disorders, wound care and, potentially, neurodegenerative diseases, osteoarthritis, and others. Additionally, allogeneic platelets are now seen as a readily available source of cells and EVs that can be exploited for targeted drug delivery vehicles. This article aims to offer an in-depth update on emerging translational applications of allogeneic platelet biotherapies while also highlighting their advantages and limitations as a clinical modality in regenerative medicine and cell therapies.

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-β, 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.

Effect of autologous platelet-rich plasma on patients with acute type A aortic dissection underwent aortic arch replacement: A retrospective cohort study

BACKGROUND

Coagulopathy and massive bleeding are common complications of patients with Stanford type A acute aortic dissection repair, and patients with these complications require many transfusions. Autologous platelet-rich plasma (PRP) is widely used to reduce the need for blood products. In the present study, we aimed to investigate the effects of PRP on blood conservation and the postoperative conditions of patients who underwent aortic arch replacement.

METHODS

Patients with aortic dissection undergoing aortic arch replacement were included initially application In all, 837 patients were divided into the PRP and non-PRP groups according to PRP use, whereupon a propensity score match was performed. The data analyzed included patient basic information, intraoperative information, postoperative biochemical examinations, and CTA reports.

RESULTS

In total, 610 patients were finally included (305 patients per group). Groups were well balanced after matching. Compared to the non-PRP group, less cryoprecipitate was transfused in the PRP group (10.0 [7.5, 11.0] vs. 10.0 [10.0, 11.5], P = 0.021), while no differences were found in packed RBC, FFP, and platelets between the two groups. Also, the surgery variables showed no differences. After surgery, patients in the PRP group showed higher postoperative serum albumin (36.43±4.20 vs. 35.39±4.40 g/L, P = 0.004) and total protein levels (59.38±6.25 vs. 58.06±7.19 g/L, P = 0.019) than the non-PRP group, but no significant differences in the levels of ALT, AST, Scr, and BUN. CTA reports showed that the proportion of patients with pleural effusion was lower in the PRP group (76.66% vs. 83.99%, OR = 1.59, 95% CI: 1.04-2.45, P = 0.028), while the proportions of pericardial effusion were not significantly different.

CONCLUSIONS

PRP application in aortic arch replacement surgery reduced the transfusion of cryoprecipitate, increased the postoperative serum albumin and total protein levels, and reduced the incidence of pleural effusion. No effect of PRP application was found on other postoperative blood indicators and CTA reports.

Impact of a Novel Hydrogel with Injectable Platelet-Rich Fibrin in Diabetic Wound Healing

Diabetic wounds are serious complications caused by diabetes mellitus (DM), which are further exacerbated by angiogenesis disorders and prolonged inflammation. Injectable platelet-rich fibrin (i-PRF) is rich in growth factors (GFs) and has been used for the repair and regeneration of diabetic wounds; however, direct application of i-PRF has certain disadvantages, including the instability of the bioactive molecules. Sericin hydrogel, fabricated by silkworm-derived sericin, is a biocompatible material that has anti-inflammatory and healing-promoting properties. Therefore, in this study, we developed a novel hydrogel (named sericin/i-PRF hydrogel) using a simple one-step activation method. The in vitro studies showed that the rapid injectability of the sericin/i-PRF hydrogel allows it to adapt to the irregular shape of the wounds. Additionally, sericin hydrogel could prolong the release of i-PRF-derived bioactive GFs in the sericin/i-PRF hydrogel. Furthermore, sericin/i-PRF hydrogel effectively repaired diabetic wounds, promoted angiogenesis, and reduced inflammation levels in the diabetic wounds of nude mice. These results demonstrate that the sericin/i-PRF hydrogel is a promising agent for diabetic wound healing.

Current Non-surgical Management of Knee Osteoarthritis

Osteoarthritis (OA) is a common chronic degenerative disease. The prevalence tends to increase with age and is influenced by underlying risk factors such as gender, obesity, joint injuries (work/sports activities), and geographic region. OA has a distinctive picture, namely, damage to the joint cartilage and the formation of new bone at the edges of the bones, also called osteophytes, due to biochemical, metabolic, physiological, and pathological changes in the joint cartilage and subchondral bone. Symptoms that can be caused include joint pain, inhibition of joint movement, crepitus, deformity, asymmetrical swelling of the joints, signs of inflammation, and changes in gait. Currently, there are various methods of managing OA in terms of reducing pain, including regeneration and non-regeneration therapy. Non-regeneration treatments include physiotherapy (exercise, biomechanical intervention, electrotherapy, diathermy), pharmacology, intra-articular injections (corticosteroids, hyaluronic acid, geniculate nerve blocks), extra-articular injections, and radiofrequency. In comparison, regeneration management includes laser and intra-articular injection (prolotherapy and PRP).

Stromal vascular fraction with platelet-rich plasma injection during surgery is feasible and safe in treatment-refractory perianal fistulising Crohn's disease: A pilot study

BACKGROUND

An unmet need remains for improved management in perianal fistulising Crohn's disease (pCD). Recently, local administration of adipose-derived cells has shown promising results.

AIMS

To assess the safety and feasibility of injection of stromal vascular fraction (SVF) with platelet-rich plasma (PRP) in patients with pCD.

METHODS

Patients ≥ 18 years with pCD were included and underwent fistula curettage, SVF with PRP injection, and closure of the internal opening. The primary endpoint was safety at 12 months. The secondary outcomes were complete radiological healing at 3 months (absence of fluid-containing tracts on MRI) and partial and complete clinical response at 3 and 12 months (closure of ≥1, respectively, all treated external opening(s)).

RESULTS

Twenty-five patients were included (35 [IQR 25-40] years; 14 [56%] female); median CD duration 4 [IQR 2-8] years. Twenty-four (95%) patients had previously undergone fistula surgery. No adverse events were encountered at lipoharvesting sites. Two (8%) patients were readmitted to hospital and six (24%) underwent unplanned re-interventions. Post-operative MRI (n = 24) showed complete radiological healing in nine (37.5%) patients. Partial clinical response was present in 48% (12/25) at 3 months and in 68% (17/25) at 12 months, and complete clinical closure in five (20%) patients at 3 months and in 10 (40%) patients at 12 months.

CONCLUSION

Injection with autologous SVF with PRP is feasible and safe in patients with treatment-refractory pCD. Early complete radiological healing was observed in more than one-third of patients, and clinical response in two-thirds of patients at 12 months.

Novel Aspects Targeting Platelets in Atherosclerotic Cardiovascular Disease—A Translational Perspective

Platelets are important cellular targets in cardiovascular disease. Based on insights from basic science, translational approaches and clinical studies, a distinguished anti-platelet drug treatment regimen for cardiovascular patients could be established. Furthermore, platelets are increasingly considered as cells mediating effects “beyond thrombosis”, including vascular inflammation, tissue remodeling and healing of vascular and tissue lesions. This review has its focus on the functions and interactions of platelets with potential translational and clinical relevance. The role of platelets for the development of atherosclerosis and therapeutic modalities for primary and secondary prevention of atherosclerotic disease are addressed. Furthermore, novel therapeutic options for inhibiting platelet function and the use of platelets in regenerative medicine are considered.

Platelet-rich plasma in the treatment of anal fistula: a systematic review and meta-analysis

OBJECTIVE

To analyse the safety and effectiveness of platelet-rich plasma (PRP) in anal fistula patients.

METHODS

Online databases including PubMed, Embase, Cochrane Library, and Web of Science were searched from inception to December 5, 2022, for eligible studies about evaluating the efficacy of platelet-rich plasma (PRP) in treating anal fistula. Literature search, screening, data extraction, and quality assessment were carried out by two independent investigators. The overall cure rate, the complete cure rate, the recurrence rate, and the adverse event rate with their 95% confidence intervals (95% CI) were the primary calculation indexes. Subgroup analyses were conducted primarily according to whether PRP was combined with other treatments. Softwares of MedCalc 18.2 and Review Manager 5.3 were used for meta-analysis.

RESULTS

A total of 14 studies with 514 patients were included in the meta-analysis. The overall cure rate of 14 studies was 72.11% (95% CI 0.64-0.79). The cure rate of PRP alone was 62.39% (95% CI 0.55-0.69). The combined cure rate of PRP with other treatments was 83.12% (95% CI 0.77-0.88). The cure rate of interventions involving PRP were superior to the cure rate of surgery methods without using PRP significantly in the 4 randomized controlled studies (RR = 1.30, 95% CI 1.10-1.54, p = 0.002). The complete cure rate of the 8 studies was 66.37% (95% CI 0.52-0.79). The recurrence rate of the 12 studies was 14.84% (95% CI 0.08-0.24). The adverse event rate of the 12 studies was 6.31% (95% CI 0.02-0.12).

CONCLUSION

PRP showed favorable safety and effectiveness in the treatment of anal fistula, especially combined with other treatment procedures.

The Statistical Fragility of Platelet-Rich Plasma as Treatment for Plantar Fasciitis: A Systematic Review and Simulated Fragility Analysis

Background

Plantar fasciitis (PF) is the most common cause of heel pain and can be a source of extensive physical disability and financial burden. Platelet-rich plasma (PRP) offers a potentially definitive, regenerative treatment modality that, if effective, could change the current paradigm of PF care. However, randomized controlled trials (RCTs) on the clinical benefits of PRP for refractory PF offer inconsistent conclusions, potentially because of the broader limitations of using P value thresholds to declare statistical and clinical significance. In this study, we use the Continuous Fragility Index (CFI) and Quotient (CFQ) to appraise the statistical robustness of data from RCTs evaluating PRP for treatment of PF.

Methods

RCTs comparing outcomes after PRP injection vs alternative treatment in patients with chronic PF were evaluated. Representative simulated data sets were generated for each reported outcome event using summary statistics. The CFI was determined by manipulating each data set until reversal of significance (α=0.05) was achieved. The corresponding CFQ was calculated by dividing the CFI by the sample size.

Results

Of 259 studies screened, 20 studies (59 outcome events) were included in this analysis. From these simulations, the median CFI for all events was 9, suggesting that varying the treatment of 9 patients would be required to reverse trial significance. The corresponding CFQ was 0.177. Studies with reported P value <.05 were more statistically fragile (CFI=10, CFQ=0.122) than studies with reported P value >.05 (CFI=5, CFQ=0.179). Of 36 outcome events reporting lost to follow-up data, 10 events (27.8%) lost ≥9 patients.

Conclusion

Our findings suggest that, on average, the statistical fragility of RCTs evaluating PRP for nonoperative PF therapy is at least comparable to that of the sports medicine literature. However, several included studies had concerningly low simulated fragility scores. Orthopaedic surgeons may benefit from preferentially relying on studies with higher CFI and CFQ values when evaluating the utility of PRP for chronic PF in their own clinical practice. Given the importance of RCT data in clinical decision making, fragility indices could help give context to the stability of statistical findings.

Level of Evidence

Level I, systematic review.

Leukocyte and Platelet-Rich Plasma (L-PRP) in Tendon Models: A Systematic Review and Meta-Analysis of in vivo/in vitro Studies

Purpose

To perform a systematic review on the application of leukocyte- and platelet-rich plasma (L-PRP) in tendon models by reviewing in vivo/in vitro studies.

Methods

The searches were performed via electronic databases including PubMed, Embase, and Cochrane Library up to September 2022 using the following keywords: ((tenocytes OR tendon OR tendinitis OR tendinosis OR tendinopathy OR tendon injury) AND (platelet-rich plasma OR PRP OR autologous conditioned plasma OR leukocyte- and platelet-rich plasma OR L-PRP OR leukocyte-richplatelet-rich plasma Lr-PRP)). Only in vitro and in vivo studies that assessed the potential effects of L-PRP on tendons and/or tenocytes are included in this study. Description of PRP, study design and methods, outcomes measured, and results are extracted from the data.

Results

A total of 17 studies (8 in vitro studies and 9 in vivo studies) are included. Thirteen studies (76%) reported leukocyte concentrations of L-PRP. Four studies (24%) reported the commercial kits. In in vitro studies, L-PRP demonstrated increased cell proliferation, cell migration, collagen synthesis, accelerated inflammation, and catabolic response in the short term. In addition, most in vivo studies indicated increased collagen type I content. According to in vivo studies reporting data, L-PRP reduced inflammation response in 71.0% of studies, while it enhanced the histological quality of tendons in 67.0% of studies. All 3 studies reporting data found increased biomechanical properties with L-PRP treatment.

Conclusions

Most evidence indicates that L-PRP has some potential effects on tendon healing compared to control. However, it appears that L-PRP works depending on the biological status of the damaged tendon. At an early stage, L-PRP may accelerate tendon healing, but at a later stage, it could be detrimental.

The biological effect of a combination of platelet lysate and amniotic membrane in buccal epithelium culture

Purpose: To study the biological effect of a combination of platelet lysate and amniotic membrane, preserved by various techniques, on human buccal epithelium culture. Materials and methods. Human amnion transplants were preserved using 3 methods: silicate drying, lyophilization, cryopreservation. The blood of healthy volunteers was used as a source of platelets. Platelet-rich plasma (PRP) with a platelet content over 1000 thousand/mcl and more was isolated from the donors blood, frozen at -80 °С and defrosted at 0–4 °С to prepare platelet lysate. Growth-stimulating effect of the amnion transplants was studied in different groups: control group 1 — without amnion and without PRP lysate; control group 2 — PRP lysate without amnion; experimental group 1 — amnion without PRP lysate; experimental group 2 — amnion samples combined with PRP lysate. The study was carried out on the example of human buccal epithelium culture of 3–5 passages. The dynamics of cell growth was evaluated after 1, 2 and 3 days from the moment of seeding. The number of cells and their viability were evaluated using original methods based on vital cell staining and their examination in a fluorescent microscope. Results. All samples of preserved amnions were non-toxic and did not damage the structural and functional characteristics of the buccal epithelium. On the other hand, the use of amnion without PRP lysate did not have a growth-stimulating effect on cells. Among the amnion samples combined with PRP lysate, the combination of lyophilized amnion and PRP lysate was the most effective during the entire study period. Conclusions. Silicate drying, lyophilization and cryopreservation of the amniotic membrane makes it possible to obtain biocompatible and non-toxic transplants, based on human amnion. Lyophilized amnions are the most optimal for saturating PRP lysate. The combination of lyophilized amnion and PRP lysate stimulates cell growth in vitro without violating their structural integrity.

Autologous Platelet-Rich Plasma (PRP) for Treating Androgenetic Alopecia: A Novel Treatment Protocol Standardized on 2 Cases

Platelet-rich plasma (PRP) treatment has emerged in recent years as a valuable, effective, and affordable treatment for androgenetic alopecia. Androgenetic alopecia is the most common type of alopecia, affecting both men and women, and is characterized by diminished hair follicles mainly pronounced in the frontal region and vertex. A considerable variety of PRP treatment regimens have been described so far, but there is no consensus on the standardization of PRP preparation or administration protocol. Our study was conducted on two patients to test the efficacy of a new PRP application protocol of only two treatments by using a combination of a PRP collecting device and a conventional kit. Efficacy of treatment was assessed after a 6-month follow-up by artificial intelligence (AI)-driven software on microscopic images of treated regions. An average number of hairs, cumulative hair thickness, and the number of follicular units increased in the vertex region of both patients by 30/59%, 35/53%, and 14/48%, respectively. The novel treatment regimen showed significant effectiveness in only six months.

The Role of Platelet-Rich Plasma on the Chondrogenic and Osteogenic Differentiation of Human Amniotic-Fluid-Derived Stem Cells

Amniotic fluid represents a new and promising source of engraftable stem cells. The purpose of this study was to investigate the in vitro effects of platelet-rich plasma (PRP) on amniotic-fluid-derived stem cells (AFSCs) on chondrogenic or osteogenic differentiation potential. Amniotic fluid samples were obtained from women undergoing amniocentesis for prenatal diagnosis at 16-18 weeks of pregnancy. Undifferentiated human AFSCs were cocultured with PRP for 14 days. The study includes two protocols investigating the effects of activated PRP using two different methods: via freeze-thaw cycles and via the addition of calcium gluconate. On the 14th day of culturing, the differentiation potential of the cocultured AFSCs was then compared with undifferentiated AFSCs. Staining with alcian blue solution (ABS) and alizarine red solution (ARS) was performed, and chondrogenic- and osteogenic-associated genes markers were investigated. ABS demonstrated enhanced glycosaminoglycan expression. Cocultured cells expressed chondrocyte-associated genes, determined by real-time polymerase chain reaction (RT-PCR), including type I collagen, type II collagen, COMP, and aggrecan. In regard to the osteogenic markers, osteopontin and bone sialoprotein, there were no changes. In particular, the activation of PRP using the freeze-thaw cycle protocol showed a higher expression of the chondrogenic markers. Our preliminary in vitro results showed that PRP has good potential in the chondrogenic differentiation of AFSCs.

Potential therapeutic effect of platelet-rich plasma and albendazole on the muscular phase of experimental Trichinella spiralis infection

Trichinellosis is a food-borne parasitic infection causing muscle damage. This study aimed to detect the potential therapeutic effect of platelet-rich plasma (PRP) alone or in combination with albendazole (ALB) on the muscular phase of experimental Trichinella infection in rats. The study was conducted on 70 rats divided into four main groups: healthy non-infected non-treated rats, non-infected rats treated with PRP, infected untreated rats (seven rats in each group), and an infected group of 49 rats. The infected group was further subdivided based on the drug therapy received. The effects of drug therapy were evaluated using parasitological and histopathological analyses. The percent reduction in the number of Trichinella spiralis larvae per gram of muscle in the PRP-treated groups (one, two, and three doses) was 43.1%, 78.8%, and 86.1%, respectively. Groups treated with combined therapy of ALB & PRP (one, two, and three doses) showed overall reduction percentages of 87.7%, 90.9% and 95.2%, respectively. In contrast, the ALB-treated group showed a 69.4% reduction. All results of the abovementioned groups were statistically significant compared to the control-infected non-treated group. The findings of the histopathological analysis were consistent with the parasitological results. Groups receiving combined therapy showed the most significant improvement in terms of the degree of inflammation and fibrosis. It can be concluded that PRP has a modulatory effect on the pathology caused by T. spiralis larvae in the muscular phase of trichinellosis. To our knowledge, this is the first study to investigate the effect of PRP on the muscular phase of T. spiralis infection.

Effect and Related Mechanism of Platelet-Rich Plasma on the Osteogenic Differentiation of Human Adipose-Derived Stem Cells

Objective

Human adipose-derived stem cells (hADSCs) are ideal seed cells for the regeneration of alveolar bone defects. Platelet-rich plasma (PRP), which is rich in growth factors, promotes tissue repair. The purpose of the present study was to investigate whether PRP promotes the osteogenic differentiation of hADSCs and to perform high-throughput sequencing to explore the possible mechanism.

Methods

hADSCs were divided into the three following groups: CON group, OM group, and PRP group. Osteogenesis was detected by Alizarin Red staining on day 14. Total RNA was extracted from the OM and PRP groups for high-throughput sequencing. The target genes of the differentially expressed osteogenic-related miRNAs were predicted, and combined miRNA/mRNA analysis was then performed. The mRNA and protein expression levels of hsa-miR-212-5p, type 1 cannabinoid receptor (CNR1), alkaline phosphatase (ALP), Runx2, osteocalcin (OCN), and collagen 1 A1 (COL1A1) in the OM and PRP groups were detected by qRT–PCR and Western blot analyses. The binding between hsa-miR-212-5p and CNR1 was detected by a dual-luciferase reporter assay.

Results

Both the OM and PRP groups exhibited enhanced proliferation of hADSCs, and the differences at 48 h and 72 h were statistically significant (P < 0.05). The PRP group had significantly more calcium nodules than the CON group (P < 0.05). Through high-throughput sequencing analysis, differential miRNA and mRNA expression profiles were obtained. During hADSC osteogenesis, the expression of hsa-miR-212-5p was downregulated, and the expression of CNR1 was upregulated. hsa-miR-212-5p was found to bind directly to the 3′ UTR of CNR1.

Conclusions

The present findings indicated that downregulation of hsa-miR-212-5p and upregulation of CNR1 may be involved in the process by which PRP promotes the osteogenic differentiation of hADSCs.

The effect of placebo in split-scalp and whole-head platelet-rich plasma trials for androgenetic alopecia differs: Findings from a systematic review with quantitative evidence syntheses

BACKGROUND

Some studies have shown that platelet-rich plasma (PRP) improves androgenetic alopecia (AGA)-while others do not. We determined whether the placebo effect significantly varies between split-scalp and whole-head trials on PRP monotherapy for AGA. Our rationale was based on the plausibility of PRP diffusing to the control (i.e., 'placebo') side of split-scalp trials. This is not possible in whole head studies.

METHODS

We systematically searched the literature for available data. Our choice of analyses and outcomes were determined by the available data.

RESULTS

Our endpoint was change in total hair density six months after baseline. Our regression showed that total hair density after six months was significantly (p<0.05) higher in the placebo arm of split-scalp trials, compared to whole-head studies, by 37 hairs/cm² . Our one-arm meta-analyses showed that the pooled change in total hair density between the PRP side and placebo side in split scalp studies was -3 hairs/cm² (p=0.37), that is, a slight decrease in hair density in the placebo side of the scalp. For whole head stdies the corresponding difference in total hair density between patients receiving PRP and those on placebo was -30 hairs/cm² (p=0.000017), that is, a much larger decrease in hair density. Patients in the placebo group in whole-head trials lost significantly more hair than in the placebo side of the split-head trials where hair loss was comparatively reduced-presumably because of PRP diffusing from the treatment side of the scalp.

CONCLUSIONS

The association between design (i.e., split-scalp vs. whole-head) and outcome, in placebo arms of AGA trials on PRP monotherapy, had never been reported. This 'design effect' could partly reconcile the incongruent conclusions across the PRP literature for AGA; furthermore, clinical guidelines can consider 'design effect' when selecting evidence to base care practices on.

Intrauterine interventions for women with two or more implantation failures: A systematic review and network meta-analysis

OBJECTIVE

To compare the effectiveness of different intrauterine interventions for women with two or more unexplained implantation failures.

DESIGN

A systematic review and network meta-analysis of randomized controlled trials (RCTs).

PATIENTS

Women with two or more implantation failures undergoing fresh or frozen embryo transfer (ET).

INTERVENTIONS

An electronic search of the following databases: Pubmed, Cochrane Central Register of Controlled Trials (CENTRAL), and Embase.

MAIN OUTCOME MEASURES

Clinical pregnancy, live birth/ongoing pregnancy, and miscarriage.

RESULTS

We included 21 RCTs(3079 women) in the network meta-analysis. The network meta-analysis showed that compared with control treatment, platelet-rich plasma(PRP), peripheral blood mononuclear cells (PBMC), granulocyte colony-stimulating factor(G-CSF), human chorionic gonadotropin(HCG), and endometrial scratch(ES) significantly increased clinical pregnancy(OR 3.78, 95% CI 2.72 to 5.25; 2.79, 95% CI 1.75 to 4.45; 1.93, 95% CI 1.37 to 2.72; 1.80, 95% CI 1.18 to 2.72; 1.75, 95% CI 1.29 to 2.36, respectively). PRP ranked the highest in improving clinical pregnancy, followed by PBMC, G-CSF, HCG, and ES. Compared with control treatment, PRP, PBMC, and ES significantly increased live birth/ongoing pregnancy (OR 5.96, 95% CI 3.38 to 10.52; OR 2.55, 95% CI 1.27 to 5.11; OR 1.70, 95% CI 1.07 to 2.69, respectively). PRP ranked the highest in improving live birth/ongoing pregnancy, followed by PBMC, and ES.

CONCLUSIONS

PRP is the most effective intrauterine intervention in improving pregnancy outcome in women with two or more implantation failures.