Efficacy of platelet-rich plasma as conservative treatment in orthopaedics: a systematic review and meta-analysis

Platelet-rich plasma for the treatment of diabetic foot ulcer: a systematic review

Background

With the increasing incidence of diabetes, diabetic foot ulcer(DFU) has become one of the most common and serious complications in people with diabetes. DFU is associated with significant morbidity and mortality, and can also result in significant economic, social and public health burdens. Due to peripheral neuropathy, peripheral vascular disease, hyperglycemic environment, inflammatory disorders and other factors, the healing of DFU is impaired or delayed, resulting in the formation of diabetic chronic refractory ulcer. Because of these pathological abnormalities in DFU, it may be difficult to promote wound healing with conventional therapies or antibiotics, whereas platelet-rich plasma(PRP) can promote wound healing by releasing various bioactive molecules stored in platelets, making it more promising than traditional antibiotics. Therefore, the purpose of this systematic review is to summarize and analyze the efficacy of PRP in the treatment of DFU.

Methods

A literature search was undertaken in PubMed, CNKI, EMB-ASE, the Cochrane Library, the WanFang Database and the WeiPu Database by computer. Included controlled studies evaluating the efficacy of PRP in the treatment of diabetic foot ulcers. The data extraction and assessment are on the basis of PRISMA.

Results

Twenty studies were evaluated, and nineteen measures for the evaluation of the efficacy of PRP in DFU treatment were introduced by eliminating relevant duplicate measures. The efficacy measures that were repeated in various studies mainly included the rate of complete ulcer healing, the percentage of ulcer area reduction, the time required for ulcer healing, wound complications (including infection rate, amputation rate, and degree of amputation), the rate of ulcer recurrence, and the cost and duration of hospitalization for DFU, as well as subsequent survival and quality of life scores. One of the most important indicators were healing rate, ulcer area reduction and healing time. The meta-analysis found that PRP was significantly improve the healing rate(OR = 4.37, 95% CI 3.02-6.33, P < 0.001) and shorten the healing time(MD = -3.21, 95% CI -3.83 to -2.59,P < 0.001)of patients with DFU when compared to the conventional treatment, but there was no significant difference in reducing the of ulcer area(MD = 5.67, 95% CI -0.77 to 12.11,P =0.08>0.05 ).

Conclusion

The application of PRP to DFU can improve ulcer healing rate and shorten ulcer healing time, but more clinical data are needed to clarify some efficacy measures. At the same time, a standardized preparation process for PRP is essential.

Efficacy of Platelet-Rich Plasma for Chronic Lateral Ankle Instability After Modified Broström-Gould surgery: A Randomized, Single-Blinded, Prospective Controlled Trial

Background

Modified Broström-Gould (MBG) surgery is frequently used for chronic lateral ankle instability (CLAI). However, conventional postoperative management (CPOM) due to prolonged immobilization may have adverse effects on tendons, ligaments, and joints, causing stiffness. This prospective, randomized controlled trial aimed to determine outcomes among patients randomized to receive CPOM plus ultrasonography-guided triple injections of leukocyte-rich platelet-rich plasma (LR-PRP) compared to patients who receive only CPOM after MBG surgery.

Methods

The present study included 40 patients with symptomatic CLAI who were candidates for the MBG surgery. The patients were randomized into 2 groups of 20, the control and PRP groups. In the PRP group, patients were injected with 3 doses of LR-PRP solution using ultrasonographic guidance. In the first injection, 2 mL of LR-PRP was injected near the injury site, and in the second and third injections, 4 mL of LR-PRP was injected in the tibiotalar joint. All patients received a short leg splint for 2 weeks, followed by 4 weeks in a walking boot. The primary outcome measure was the visual analog scale (VAS), and the secondary outcome measures were the American Orthopaedic Foot & Ankle Society (AOFAS) ankle-hindfoot scale and ankle total range of motion (total ROM). The assessment was performed at baseline and 3 and 6 months after surgery.

Results

The mean VAS and AOFAS scores improved significantly in both groups 6 months after surgery (P < .001). However, the PRP group did not significantly improve in VAS or AOFAS scores compared with the control group. No clinically significant difference was observed between the 2 groups regarding the total ROM scores at month 3.

Conclusion

The application of LR-PRP after MBG surgery did not show any superior clinical or functional improvement over CPOM.

Level of Evidence

Level II, prospective randomized trial.

Platelet-rich plasma for the treatment of alopecia: a systematic review and meta-analysis

BACKGROUND

The number of articles evaluating the efficacy of platelet-rich plasma (PRP) in androgenetic alopecia (AGA) and alopecia areata (AA) has increased exponentially during the last years. This systematic review and meta-analysis is aimed at evaluating the benefit of PRP in the treatment of alopecia.

MATERIAL AND METHODS

We searched MEDLINE (through PUBMED), Embase, and CENTRAL for relevant data. Treatment effect was described by mean difference (MD) and risk difference with 95% confidence intervals (CI). The GRADE system was used to assess the certainty of the body of evidence.

RESULTS

We found 27 controlled trials (1,117 subjects) that met our inclusion criteria: 18 trials (713 subjects) in patients with AGA, and 9 (404 subjects) in patients with AA. Eleven studies had a split head design. There was heterogeneity in types of PRP (e.g., activated and non-activated) and administration schedules. PRP was compared to saline injections (18 studies), local steroid injections (4 studies) and other comparators (5 studies). Most commonly reported outcomes were hair density and hair regrowth. It was not possible to pool all outcome data because of heterogeneity in reporting, and because reporting was often limited to a single study. Compared to saline injections, PRP injections increased hair density over a medium-term follow-up (MD, 25.6 hairs/cm²; 95 % CI: 2.62-48.57), but the evidence was rated as low quality due to inconsistency and risk of bias. In individuals with AA, it is unclear whether PRP injection compared with triamcinolone injection increase the rate of subjects with hair regrowth (very-low quality of evidence due to inconsistency, imprecision, and risk of bias). There were no serious adverse events related to PRP injection or control treatments.

CONCLUSIONS

There is limited evidence showing benefit of PRP for treatment of alopecia, and most of this evidence is of low quality.

Treatment of chronic lateral epicondylosis: a randomized trial comparing the efficacy of ultrasound-guided tendon dry needling and open-release surgery

OBJECTIVE

Evaluate the efficacy of ultrasound-guided dry needling and open-release surgery in reducing pain and improving function in workers with lateral epicondylosis refractory to at least 6 months of nonsurgical management.

METHODS

We randomly assigned participants in a 1:1 ratio to receive dry needling or surgery. The primary outcome was the Patient Rated Tennis Elbow Evaluation (PRTEE) score at 6 months. Secondary outcome measures examined the impact of these techniques on professional activity, grip strength, and Global Rating of Change and Satisfaction scales. Statistical analyses included mixed-effects models and Fisher's exact tests.

RESULTS

From October 2016 through June 2019, we enrolled 64 participants. Two participants were excluded, and data from 62 participants (48 ± 8 years, 33 men) with a mean duration of symptoms of 23 ± 21 months were analyzed. Baseline characteristics were similar in both groups. In the intention-to-treat analysis, no treatment-by-time interaction was observed (F_(4,201) = 0.72; p = .58). The least-squares mean difference from baseline in PRTEE scores at 6 months was 33.4 (CI 25.2 - 41.5) in the surgery group and 26.9 (CI 19.4 - 34.4) in the dry needling group (p = .25). The proportion of successful treatment was 83% (CI 63 - 95%) and 81% (CI 63 - 93%) in the surgery and dry needling groups, respectively (p = 1.00). Changes in secondary outcomes were in the same direction as those of the primary outcome. No adverse event occurred.

CONCLUSIONS

Ultrasound-guided dry needling resulted in comparable improvement in outcome scores on scales of pain, physical function, and global assessment of change and satisfaction than open-release surgery.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02710682 KEY POINTS: • In patients with chronic lateral epicondylosis, ultrasound-guided tendon dry needling provides comparable therapeutic efficacy to open-release surgery. • Ultrasound-guided tendon dry needling allows for an earlier return to work and may be less costly than open-release surgery. • Care management guidelines should recommend treatment by ultrasound-guided tendon dry needling before open-release surgery.

Platelet-Rich Plasma in the Treatment of Facet Mediated Low Back Pain: A Comprehensive Review

Background

Facet-mediated pain is a major cause of low back pain and as a result, is a significant cause of morbidity, including disability and reduced functionality.

Setting

The present investigation involved a PubMed literature review between June 1, and 2021-January 1, 2022.

Methods

We systematically reviewed was carried Pubmed using the search terms "platelet-rich plasma", "inflammatory mediators", "facet arthropathy", "axial back pain", and "leukoreduction". Data extraction and quality assessment were performed by 3 independent reviewers. Out of the studies analyzed 2 were retrospective, while 1 was a prospective study.

Results

PRP injections for facet mediated or modulated pain are an alternative to conventional pharmacotherapies and interventional injections/radiofrequency. There are limited numbers of studies in world literature at present.

Limitations

Small number of articles in the world literature and small numbers of patients in those published studies.

Conclusions

At present, there are limited studies in the literature; however, larger well-designed studies are warranted to precisely understand efficacy, potential side effects and best practice techniques for PRP injections for facet mediated or modulated pain.

PRP Versus Standard of Care for Venous leg Ulcers: A Systematic Review and Meta-Analysis of Prospective Comparative Studies

Venous leg ulcers (VLUs) are chronic and recalcitrant lower limb wounds that affect millions of patients annually, severely reducing their quality of life, and causing a significant burden on the health care system. Recently, Platelet rich plasma (PRP) has been used to improve healing of VLUs. This systematic review aimed at evaluating the effectiveness of PRP versus the standard of care commonly used to treat VLUs. Ten prospective studies (8 randomized) met the inclusion criteria comprising 451 patients with 527 VLUs. Results were as follows: a) the weighted Odds Ratio (OR) of the mean healing rate was 2.84 (95% CI = 1.160 to 5.056, I2 = 41.4%, p = 0.0004), b) the mean healed ulcer areas were 79.2 ± 19% for the PRP group and 51.7 ± 36% for the control group (p = 0.007) in favor of the PRP group, and c) the weighted infection OR showed no significant difference between both groups. Additionally, negative correlations were found between healing rate and duration of VLUs and initial size of the ulcers. This meta-analysis demonstrated significant beneficial effects of PRP versus standard of care on healing rate, reduction in surface, and reduction in healing time of VLUs. Infection and other complications were similar to standard of care. Therefore, our analytical data would support the use of PRP as a safe and effective treatment for VLUs.

A Biomimetic Platelet-Rich Plasma-Based Interpenetrating Network Printable Hydrogel for Bone Regeneration

Repair of bone defects caused by trauma or diseases is the primary focus of prosthodontics. Hydrogels are among the most promising candidates for bone tissue regeneration due to their unique features such as excellent biocompatibility, similarities to biological tissues, and plasticity. Herein, we developed a type of novel biomimetic interpenetrating polymeric network (IPN) hydrogel by combining methacrylated alginate and 4-arm poly (ethylene glycol)-acrylate (4A-PEGAcr) through photo-crosslinking. Platelet-rich plasma (PRP), a patient-specific source of autologous growth factors, was incorporated into the hydrogel, and thereafter the hydrogels were biological mineralized by simulated body fluid (SBF). Physical properties of hydrogels were comprehensively characterized. In vitro studies demonstrated that the incorporation of PRP and biomineralization promoted the biocompatibility of hydrogel. Strikingly, the osteogenic bioactivities, including ALP activity, mineralized nodule formation, and expression of osteogenic markers were found substantially enhanced by this biomineralized PRP-hydrogel. Finally, a rabbit model of bone defect was employed to assess in vivo bone regeneration, micro-CT analysis showed that the biomineralized PRP-hydrogels could significantly accelerate bone generation. We believed that this novel biomineralized PRP-incorporated IPN hydrogel could be promising scaffolds for bone tissue regeneration.

In vitro effect of triamcinolone and platelet-rich plasma on cytokine levels of elbow lateral epicondylitis-derived cells

Background

The pathogenesis and treatment of lateral elbow epicondylitis (LEE) are still controversial. The purpose of the current study was to evaluate the production of inflammatory cytokines by LEE-derived cells and to compare the anti-inflammatory effect of triamcinolone acetonide with platelet-rich plasma (PRP) on cytokines production in primary culture of these cells.

Methods

Third passage cells from primary cultures of LEE were assessed for the production of the cytokines IL-1β, IL-6, IL-8, IL-10 and TNF-α by immune-enzymatic assay (ELISA), after the treatment with 1, 10 and 100 μM triamcinolone compared to no treated controls at the time points 6, 12, 18, 24, 48, 72 and 96 h, and to PRP at 48, 72 and 96 h.

Results

The cytokines IL-6 and IL-8 were produced in high concentrations by LEE cells. One, 10 and 100 μM triamcinolone induced significant decrease in the production of IL-6 and IL-8 at 48, 72 and 96 h, adding the time point 12 h for IL-8. Compared to controls, PRP caused a significant increase in the production of IL-6 and IL-8 and there was a significant increase in IL-10 production with the use of 100 μM triamcinolone at 48 h. The production of IL1-β and TNF-α was very low and did not change when the cultures were treated with triamcinolone or PRP.

Conclusion

LEE-derived cells produce IL-6 and IL-8, confirming the inflammatory nature of this condition. While triamcinolone inhibited the production of IL-6 and IL-8 by LEE cells, PRP induced an increase in these cytokines compared with controls.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-02990-0.

Platelet-Rich Plasma for Rheumatoid Arthritis: A Case Series

Rheumatoid Arthritis (RA) is a chronic disease characterized by severe inflammation that leads to degradation of articular cartilage and the formation of bony erosions. Currently, certain anesthesiologist-led pain management clinics have begun to take on a collaborative role in the treatment of patients with RA, as this progressive disease impairs work capacity due to chronic pain. We present three clinical cases in which platelet-rich plasma (PRP) was used for the treatment of RA in patients seeking a new therapy for pain control and improved range of motion, specifically in certain joints of the hand. The Patient Activity Scale II was employed as a standardized method to assess RA disease severity, recorded on the day of injection, at one month, at three months, and at six months. All of the included patients, ages 49, 60, and 63, had an established diagnosis of RA affecting the proximal interphalangeal and metacarpophalangeal joints of the hand. Over the course of six months, two out of three patients reported a 20% reduction in pain from the initial visit and a 30% improvement in overall well-being. The third patient noted a 50% decrease in pain from the initial visit and a 50% improvement in overall well-being. PRP treatment consistently resulted in functional improvement for each of the three patients treated, while also reducing long term pain and inflammation. Initial clinical and laboratory studies have shown that autologous plasma rich in platelets serves as a source of an abundance of growth factors once activated. The multitude of these growth factors injected into and around the diseased joints improves functionality in patients with RA indicating PRP may be a safe and beneficial therapy in patients with RA primarily affecting the joints of the hand.

Comparison of the effectiveness of extensor muscle strengthening exercise by itself, exercise with polydeoxyribonucleotide injection, and exercise with extracorporeal shockwave therapy in lateral epicondylitis: a randomized controlled trial

Background

Extensor muscle strengthening exercises with counterforce braces (EX) is a conventional conservative treatment for lateral epicondylitis (LE) of the elbow. In addition, polydeoxyribonucleotide (PDRN) or extracorporeal shockwave therapy (ESWT) has been recently used for LE.

Methods

Sixty-three patients with chronic LE participated in this study and randomly allocated in three groups (G1: EX, G2: EX+PDRN injection, and G3: EX+ESWT). All of the three groups were taught to perform EX at the first out-patient department (OPD) visit. Group 2 was injected with 3 mL PDRN (5.625 mg/3 mL), while group 3 received ESWT at the first OPD visit. Visual analog scale pain score, Mayo elbow performance score (MEPS), and ultrasonographic examination were checked before, 6 weeks, and 12 weeks after the treatments.

Results

Overall functional scores and ultrasonographic findings in all three groups improved after treatment. The mean MEPS in group 2 improved more than groups 1 and 3 at 6 weeks (G1, 56.9>62.4; G2, 54.3>65.0; G3, 55.7>62.6), and more than group 1 at 12 weeks (G1, 56.9>67.9; G2, 54.3>73.6). The mean common extensor tendon depth (CETD) on ultrasonography in group 2 increased more than groups 1 and 3 at 6 and 12 weeks (6 weeks: G1, 0.385>0.386; G2, 0.332>0.392; G3, 0.334>0.357; 12 weeks: G1, 0.385>0.409; G2, 0.332>0.438; G3, 0.334>0.405 [cm]).

Conclusions

PDRN injections combined with EX exhibited a greater improvement in mean MEPS and mean CETD compared to EX only or EX combined with ESWT for LE within the 12 weeks follow-up.

A Systematic Review of Systematic Reviews on the Epidemiology, Evaluation, and Treatment of Plantar Fasciitis

The number of systematic review and meta-analyses on plantar fasciitis is expanding. The purpose of this review was to provide a comprehensive summary of reviews on the topic pertaining to plantar fasciitis, identify any conflicting and inconsistent results, and propose future research direction. A qualitative review of all systematic reviews and meta-analyses related to plantar fasciitis up to February 2021 was performed using PubMed, Embase, Web of Science, and the Cochrane Database. A total of 1052 articles were initially identified and 96 met the inclusion criteria. Included articles were summarized and divided into the following topics: epidemiology, diagnosis, and treatment. While the majority of reviews had high level of heterogeneity and included a small number of studies, there was general consensus on certain topics, such as BMI as a risk factor for plantar fasciitis and extracorporeal shockwave therapy as an effective mode of therapy. A qualitative summary of systematic reviews and meta-analyses published on plantar fasciitis provides a single source of updated information for clinicians. Evidence on topics such as the epidemiology, exercise therapy, or cost-effectiveness of treatment options for plantar fasciitis are lacking and warrant future research.

Autologous Platelet-Rich Plasma Efficacy in the Field of Regenerative Medicine: Product and Quality Control

Platelet-rich plasma (PRP) has emerged as a significant regenerative therapy used alone or combined mainly with stem cells, autologous fat grafts, hyaluronic acid, and biomaterials in a variety of medical fields, especially in hair regrowth, wound healing, and sports and rehabilitation medicine. However, the results obtained with this biologic therapy are heterogeneous and conflicting. The observed disparities in the effectiveness of PRP therapies may be due to a lack of standardization in blood processing and preparation. This article is aimed at reviewing the main biological parameters that need to be documented for a thorough reporting of quantitative and qualitative characteristics of the PRP injected, to allow a comparison between the quality of samples and the clinically obtained results and advance the efforts towards treatment standardization.

The Use of Platelet-Rich Plasma for Treatment of Tenodesmic Lesions in Horses: A Systematic Review and Meta-Analysis of Clinical and Experimental Data

Simple Summary

Tenodesmic injuries are key problems for sport horses. Several therapies have been developed over the years, including platelet-rich plasma (PRP), an autologous product that should stimulate tissue regeneration with its high concentration of growth factors. Nowadays, there are conflicting reports concerning the effect of PRP in tenodesmic lesions. The aim of our systematic review was to determine the effect of PRP on tendons and ligaments healing through a meta-analysis, a process to determine consensus from across published studies. The meta-analysis is the quantitative component of a systematic review, a statistical synthesis of the published data about a topic. We selected studies that evaluate PRP therapy in vitro or in vivo, most of which had a high risk of bias. The results found there is no evidence that PRP enhances the healing of tendon and ligament injuries. In the future, further unbiased, blinded, and controlled studies are needed to clarify the efficacy of this platelet concentrate in the treatment of equine tendon and ligament injuries.

Abstract

The use of platelet-rich plasma (PRP) to enhance tenodesmic lesion healing has been questioned over the years. The aim of this study was to evaluate current literature to establish the effectiveness of PRP for treating tenodesmic lesions through a systematic review, in accordance with the PRISMA guidelines, and a meta-analysis. Studies comparing PRP with placebo or other treatments for horses with tenodesmic injuries or evaluated PRP effect on tendon and ligament explants were included. Outcomes were clinical, ultrasound, histologic, molecular evaluation, and adverse effects. Two authors independently extracted data and assessed each study’s risk of bias. Treatment effects were evaluated using risk ratios for dichotomous data, together with 95% CI. Data were pooled using the random-effects model. The quality of the evidence for each outcome was assessed using GRADE criteria. Twenty-four trials met inclusion criteria for systematic review, while fifteen studies were included in the meta-analysis. Results showed no significant differences in the outcomes between PRP and control groups. Finally, there is no definitive evidence that PRP enhances tendons and ligaments healing. Therefore, there is a need for more controlled trials to draw a firmer conclusion about the efficacy of PRP as a treatment for tenodesmic lesions in the horse.

THE MANAGEMENT OF PROXIMAL HAMSTRING TENDINOPATHY IN A COMPETITIVE POWERLIFTER WITH HEAVY SLOW RESISTANCE TRAINING - A CASE REPORT

Background and Purpose

Proximal hamstring tendinopathy is a chronic, overuse condition that commonly develops in athletes. Eccentric exercise has been widely accepted in the clinic as the treatment of choice for the management of tendinopathies. However, this form of treatment has seldom been compared to other forms of load-based management for hamstring tendinopathies. Heavy slow resistance training, which consists of both concentric and eccentric phases, increases the loading time experienced by the tendon compared to eccentric only exercises. Heavy slow resistance training has achieved positive clinical results in the management of Achilles and patellar tendinopathy.

Purpose

The purpose of this case report is to describe the outcomes of a powerlifter with proximal hamstring tendinopathy who responded favorably to a heavy slow resistance biased rehabilitation program after traditional, conservative management failed to alleviate symptoms.

Case Description

A 31-year-old male competitive powerlifter was seen in physical therapy for the management of proximal hamstring tendinopathy. The subject had experienced long duration pain localized at the ischial tuberosity combined with hip weakness that limited his ability to lift weigtht and sit for longer than 30 minutes. Treatment included a 12-week heavy slow resistance program with the focus of increasing load intensity.

Outcomes

Numeric pain-rating scale was assessed at baseline, after a 12-week heavy slow resistance protocol, and 12 months post protocol. Within four weeks of starting the heavy slow resistance program, the subject noted a meaningful decrease in pain. The subject experienced clinically important improvements in numeric pain-rating scale immediately after the protocol and these improvements remained 12 months after completing the protocol. The subject was able to return to competitive powerlifting after the 12-week program.

Discussion

A meaningful change in pain occurred within four weeks of starting the program and continued improvement throughout the remainder of the 12 weeks with outcomes maintained 12 months after completing the program suggests that increasing the loading strategy with a heavy slow resistance program was helpful for this subject.

Level of Evidence

4.

Improved outcomes after mesenchymal stem cells injections for knee osteoarthritis: results at 12-months follow-up: a systematic review of the literature

PURPOSE

According to the World Health organization (WHO), more than 10% in people older than 60 years suffer from osteoarthritis (OA). Over the last years, there has been an increased interest around regenerative medicine, especially regarding stem cell treatments and related applications. We hypothesize that stem cell therapies can represent a feasible option for idiopathic knee OA, delaying or even avoiding the joint replacement. To emphasize the potential of percutaneous injections of mesenchymal stem cells for knee OA, a comprehensive systematic review of the literature was conducted.

MATERIAL AND METHODS

Two independent authors (FM, GC) performed the literature search. This study was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). The main databases were accessed: Pubmed, Embase, Google Scholar, Cochrane Systematic Reviews, Scopus, AMED. For this systematic review, all articles treating percutaneous injections of mesenchymal stem cells for knee OA were considered. Because of the rapid advancements promoted by the scientific progress on stem cell expansion and processing, only articles published within the last five years were included. Solely articles reporting the outcomes of interest across 6- and 12-month follow-up were recruited for eligibility. We included only studies reporting quantitative data under the outcomes of interest. We referred for the quality assessment to the Coleman Methodology Score (CMS). The statistical analysis was performed with Review Manager Software 5.3 (The Nordic Cochrane Centre, Copenhagen).

RESULTS

A total of 18 studies were enrolled in the present study, comprising 1069 treated knees. The mean age of the samples was 57.39 ± 7.37 years. 72% of the included studies harvested the stem cells from the iliac crest (bone marrow-derived MSCs), the remaining 28% from the adipose tissue (adipose-derived MSCs). The mean visual analogic scale improved from 18.37 to 30.98 and 36.91 at 6- and 12-month follow-up, respectively. The mean WOMAC score improved from 25.66 to 25.23 and 15.60 at 6- and 12-month follow-up, respectively. The mean walking distance improved from 71.90 to 152.22 and 316.72 at 6- and 12-month follow-up, respectively. The mean Lequesne scale improved from 33.76 to 12.90 at 12-month follow-up. The KOOS score improved from 41.07 to 8.47% and 18.94 at 6- and 12-month follow-up. All the KOOS subscales improved significantly from the baseline. A total of 136 (12.7%) local complications were detected.

CONCLUSION

According to the current evidences and the main findings of this systematic review, we reported that MSC infiltrations for knee OA can represent a feasible option, leading to an overall remarkable improvement of all clinical and functional considered outcomes, regardless of the cell source. Patients treated at earlier-degeneration stages reported statistically significant greater outcomes. The pain and function scores were improved considerably, thus, leading to a significant improvement of patient participation in recreational activities and quality of life.

Platelet-rich plasma and regenerative dentistry

Regenerative dentistry is an emerging field of medicine involving stem cell technology, tissue engineering and dental science. It exploits biological mechanisms to regenerate damaged oral tissues and restore their functions. Platelet‐rich plasma (PRP) is a biological product that is defined as the portion of plasma fraction of autologous blood with a platelet concentration above that of the original whole blood. A super‐mixture of key cytokines and growth factors is present in platelet granules. Thus, the application of PRP has gained unprecedented attention in regenerative medicine. The rationale underlies the utilization of PRP is that it acts as a biomaterial to deliver critical growth factors and cytokines from platelet granules to the targeted area, thus promoting regeneration in a variety of tissues. Based on enhanced understanding of cell signalling and growth factor biology, researchers have begun to use PRP treatment as a novel method to regenerate damaged tissues, including liver, bone, cartilage, tendon and dental pulp. To enable better understanding of the regenerative effects of PRP in dentistry, this review describes different methods of preparation and application of this biological product, and provides detailed explanations of the controversies and future prospects related to the use of PRP in dental regenerative medicine.

Platelet Rich Plasma for Treatment of Rheumatoid Arthritis: Case Series and Review of Literature

Platelet-rich plasma (PRP) is an autologous blood product with platelets above circulating levels and releases several growth factors after activation. PRP may help to decrease joint inflammation by modulating synovial cell proliferation and differentiation and inhibition of catabolic pathways in various articular conditions. Though PRP has shown good efficacy in osteoarthritis and other musculoskeletal conditions such as synovitis, epicondylitis, skeletal muscle injuries, and tendinopathy, there is limited experience for the use of PRP in patients with rheumatoid arthritis. Precise mechanisms of action of PRP are not known. We present clinical experience for treatment with PRP (2–4 ml) in four patients with rheumatoid arthritis who had inadequate response and persistent pain and inflammation with intra-articular steroids. Irrespective of past and ongoing treatments and duration of disease, all patients showed improvement in the visual analog scale and disease activity score of 28 joints at 4 and 8 weeks after injection. There was an improvement in joint inflammation on ultrasound imaging in some patients. These effects were sustained for up to 1 year. No adverse effects were reported in any patient. PRP may be a safe and useful therapy in patients with rheumatoid arthritis who fail to respond to one or more established treatment options.

Serum eye drops for the treatment of ocular surface diseases: a systematic review and meta-analysis

BACKGROUND

The use of blood-derived eye drops for topical treatment of ocular surface diseases has progressively increased in recent years.

MATERIALS AND METHODS

To evaluate the use of serum eye drops in ocular surface disorders, we performed a systematic search of the literature.

RESULTS

In this systematic review, we included 19 randomised controlled trials (RCTs) investigating the use of serum eye drops in 729 patients compared to controls. For the quantitative synthesis, we included only 10 RCTs conducted in patients with dry eye syndrome comparing autologous serum to artificial tears. At 2-6 weeks, no clear between-group differences in Schirmer test (MD 1.05; 95% CI: -0.17-2.26) and in fluorescein staining (MD -0.61; 95% CI: -1.50-0.28) were found (very low-quality evidence, down-graded for inconsistency, serious risk of biases, and serious imprecision). Slightly higher increase in tear film break-up time (TBUT) scores in autologous serum compared to control (MD 2.68; 95% CI: 1.33-4.03), and greater decrease in ocular surface disease index (OSDI) in autologous serum compared to control (MD -11.17; 95% CI: -16.58 - -5.77) were found (low quality evidence, down-graded for serious risk of bias, and for inconsistency). For the Schirmer test, fluorescein staining and TBUT, data were also available at additional follow-up timing (2-12 months): no clear between-group differences were found, and the quality of the evidence was graded as low/very-low.

CONCLUSIONS

In patients with dry eye syndrome, it is unclear whether or not the use of autologous serum compared to artificial tears increases Schirmer test and fluorescein staining scores at short-term and medium-/long-term follow up. Some benefit at short-term follow up for the outcome of TBUT and OSDI was observed, but the quality of the evidence was low.

Platelet-rich plasma for sports-related muscle, tendon and ligament injuries: an umbrella review

BACKGROUND

Platelet-rich plasma (PRP) has been used in different non-transfusion indications due to its role in tissue regeneration and healing. The aim of this overview of systematic reviews (umbrella review) is to provide a summary of the existing research syntheses related to PRP use for sports-related muscle, tendon and ligament injuries.

MATERIALS AND METHODS

Literature searches were performed in MEDLINE, Embase, and Cochrane Library to identify systematic reviews focusing on PRP use for sports-related muscle, tendon and ligament injuries. The methodological quality of included studies was assessed using the checklist for systematic reviews and research syntheses developed by the Joanna Briggs Institute and the GRADE assessment.

RESULTS

Twenty-two studies met the inclusion criteria. Five studies evaluated PRP use for acute muscle injury, and 17 evaluated PRP use for tendon and ligament injury. Studies were heterogeneous in terms of the dose and number of PRP injections, and the control groups. Three of the 5 reviews evaluating acute muscle injury concluded that PRP had no effect on the outcomes considered. One review shows superior efficacy of rehabilitation exercise compared to PRP. One review shows that PRP may result in an earlier return to sport for acute grade I-II injury. Eight out of the 17 reviews evaluating PRP for tendon and ligament injuries show a statistically significant (p<0.05) difference in pain and/or function outcome measures favouring PRP compared to controls, although most of the observed differences were small. Adverse events data and quality of life outcomes were rarely analysed or reported in the included studies and were considered clinically insignificant.

DISCUSSION

In most of the included reviews, the available evidence was judged to be of low/very low quality due to risk of bias, inconsistency and imprecision, thus making the level of certainty of these findings low and not adequate to support the general use of PRP in this setting.

The use of platelet-rich plasma in oral surgery: a systematic review and meta-analysis

BACKGROUND

The aim of this systematic review and meta-analysis was to evaluate the benefit of platelet rich plasma (PRP) in oral surgery.

MATERIALS AND METHODS

We performed a systematic search of the literature. The GRADE system was used to assess the certainty of the body of evidence.

RESULTS

We found 21 randomised controlled trials that met our inclusion criteria: 12 studies included patients with periodontal defects, five studies focused on healing of extraction sockets, three studies on sinus lift augmentation, and one study on periapical osseous defects. However, for the quantitative synthesis (meta-analysis), we evaluated "periodontal defects" studies only, since for other clinical contexts the number of studies were too low and the procedural heterogeneity was too high to allow pooling of data. PRP-containing regimens were compared to non-PRP-containing regimens. Primary outcomes for the evaluation of periodontal defects were probing depths, clinical attachment level, gingival recession, and radiographic bone defect. It is not usually clear whether or not the use of PRP compared to controls affects "probing depth" at long-term follow up; the between group differences were small and unlikely to be of clinical importance (i.e., very low quality of evidence). For the other outcomes analysed ("clinical attachment levels", "gingival recession", "bony defect"), we observed a very slight marginal clinical benefit of PRP compared to controls. The available evidence for these comparisons was rated as low quality as most of the studies selected showed inconsistency, imprecision, and risk of bias.

DISCUSSION

Evidence from a comparison between the use in oral surgery of PRP-containing regimens compared to other regimens not-containing PRP was of low quality. The results of the meta-analysis, limited to studies in patients with periodontal defects, document that PRP was slightly more effective compared to controls not-containing PRP.

Platelet-Rich Plasma for the Treatment of Low Back Pain: a Comprehensive Review

PURPOSE OF REVIEW

Back pain is a growing problem worldwide, incurring enormous economic costs and disability. Current treatment modalities often provide adequate relief but fail to address underlying conditions. Regenerative cellular modalities aim to restore anatomical function in degenerative conditions which may cause low back pain. Platelet-rich plasma (PRP) consists of an increased concentration of autologous platelets suspended in a small amount of plasma. PRP can be administered via injection or topically and is prepared using various techniques.

RECENT FINDINGS

While a unifying mechanism of action is not well understood, biochemical and cellular changes involved in inflammation and mechanical structure have been detected in both in vitro and in vivo studies. At a higher level, PRP injection research utilizing animal models and patient data have provided insights into pain relief, chondroprotection, and factors that impact the therapy's efficacy. Recently, a small number of studies have promoted PRP injection as a relatively safe means of treating patients with degenerative disc disease who have failed other means of managing their lower back pain. PRP injections for sacroiliac joint-related pain are not an accepted or common treatment modality; the evidence for their efficacy remains to be seen outside of small RCTs and case reports. A small number of prospective trials have suggested there may be some benefit to using PRP injection in the treatment of pain or functional decline caused by facet joint arthropathy. These commonly used modalities require further study to improve quality of evidence and to investigate the safety and efficacy of PRP injections for various common causes of chronic low back.

Platelet-Rich Plasma Intramuscular Injections - Antinociceptive Therapy in Myofascial Pain Within Masseter Muscles in Temporomandibular Disorders Patients: A Pilot Study

Background and Objective: The objective of this study was to explore the nociceptive effect of platelet-rich plasma (PRP) intramuscular injections in myofascial pain of masseter muscles in patients with TMD. Methods: Patients diagnosed with myofascial pain were assessed for eligibility for the study. Masticatory muscle disorder was diagnosed based on the Research Diagnostic Criteria for Temporomandibular Disorders (Ia and Ib). A total of 80 patients were enrolled in the study; 58 of them (21 male and 37 female, 29.4 ± 6.53 years old) met the inclusion criteria and were randomized to one of the two groups: Group I (n = 29) and Group II (n = 29). The first group received injections with PRP and the second group received injections with isotonic saline as the control group (0.9% NaCl). The Visual Analog Scale (VAS) was used to determine the pain intensity changes during follow-up visits in each group. Results: A significant improvement in pain intensity in VAS scale was observed, with 58% reduction in the experimental group and 10.38% in the control placebo group, 5 days after the injections (Day 5). The pain intensity reduction (VAS) 14 days after the injections (Day 14) in experimental group was 47.16 and 4.62% in control group, according to the baseline values (Day 0). Conclusions: Intramuscular injection of PRP was a successful method for reducing myofascial pain within masseter muscles in temporomandibular disorders patients. However, the use of PRP for the treatment of myofascial pain within masticatory muscles requires further, clinical trials evaluation. Clinical Trial Registration: Bioethical Commission at the Silesian Medical Chamber in Katowice, Poland 44/2017 as well as at ClinicalTrials.gov NCT03323567 (December 13, 2017).