Platelet-Rich Plasma Use in Musculoskeletal Disorders: Are the Factors Important in Standardization Well Understood?

The Role of Platelet-Rich Plasma Injection for Muscle Strains in Athletes

Muscle tears/strains are among the most common musculoskeletal injuries, posing a serious challenge for sports medicine. Aiming to reduce the time to return to play and the rate of reinjuries, apart from the traditional conservative treatments and rehabilitation protocols, new and innovative therapeutic options have emerged, particularly platelet-rich plasma (PRP). This study aims to present the available evidence regarding PRP injection for the treatment of muscle strains in athletes. Two databases were searched for articles published between January 2012 and December 2022 in Portuguese or English. The query used for the PubMed database was ("Muscles/injuries"[Mesh]) AND ("Athletes"[Mesh] OR "Athletic Injuries"[Mesh]) AND "Platelet-Rich Plasma"[Mesh], while for the Web of Science database the search was performed for "Platelet-rich plasma" AND "Muscle injuries" AND ("Athletes" OR "Athletic injuries"). Eleven studies involving athletes diagnosed with muscle injuries who received treatment with PRP injection alone, or in combination with traditional conservative treatment, compared to a control group, were included. Four randomized controlled trials, four systematic reviews/meta-analyses, two retrospective studies, and one comparative study were included. Current evidence from the highest-quality studies does not support the hypothesis of reduction of time to return to play and the rate of reinjuries after PRP injection, even though some studies reported positive results. However, the available evidence suggests that PRP might have a beneficial effect on the pain perceived by athletes following an acute muscle strain. It is challenging to arrive at definitive conclusions and translate these findings into a clinical context for treating muscle strains in athletes. The existing trials present several inconsistencies and limitations, with a heterogeneous set of patients and injuries, as well as the use of different and inconsistent methods for preparing, administering, and measuring the effects of PRP. To achieve consistent outcomes, standardizing PRP administration procedures is essential.

Platelet-Rich Plasma vs Extracorporeal Shock Wave Therapy in the Treatment of Plantar Fasciitis at 3-6 Months: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Plantar fasciitis (PF) is a common foot disorder with variability in treatment strategy. Two effective management techniques include platelet-rich plasma (PRP) injections and extracorporeal shock wave therapy (ESWT). The purpose of this meta-analysis is to compare the effectiveness of PRP vs ESWT in the management of PF.

METHODS

A systematic search was performed of PubMed, Cochrane, and Google Scholar for randomized controlled trials comparing PRP to ESWT. Studies met inclusion criteria if mean and SDs for visual analog scale (VAS) pain scores and plantar fascia thickness (PFT) were reported. Mean differences were used to compare VAS pain score and PFT between PRP and ESWT.

RESULTS

Six randomized controlled trials, comparing a total of 214 subjects in the PRP group and 218 subjects in the ESWT group, were analyzed. A significantly greater statistical improvement was seen in the PRP group in VAS pain (mean difference = -0.67 [95% CI -1.16, -0.18], P = .007) and plantar fascia thickness (PFT) (mean difference = -0.56 [95% CI -0.77, -0.35], P < .001).

CONCLUSION

PRP had a statistically higher pain reduction than ESWT, but the difference does not reach clinical significance in this meta-analysis.

The Invasive Management of Pain: Diagnosis and New Treatment Options

Both the diagnosis and treatment of pain are evolving, especially in interventional approaches. Diagnosis of low back pain combines old and new methodologies, in particular, it involves an expanded role for ultrasound. While low back pain is a common complaint, there are many etiologies to the condition which must be explored before a final diagnosis can be made and treatment planned. Tumors and infections are rarely involved in low back pain but should be ruled out in the initial phase itself since failing to address them early can have devastating consequences. Some invasive treatments seem promising in the management of low back pain. Treating musculoskeletal pain with regenerative medicine, such as platelet-rich plasma, holds great promise. Autologous blood products are safe and may help stimulate the body's own responses for regeneration. The so-called "orthobiologics" play a role in sports medicine and the treatment of musculoskeletal pain. Neuromodulation, especially spinal cord stimulation, is undergoing a renaissance with new waveforms, devices, and a greater albeit incomplete understanding of its mechanisms of action. Spinal cord stimulation is not a first-line therapy and not all patients or all back problems respond to this treatment. Nevertheless, the therapy can be safe, effective, and cost-effective with appropriate patient selection. Radiofrequency ablation of nerves in the form of neurotomy can be effective in reducing the pain of osteoarthritis. These procedures, including the newer cooled radiofrequency neurotomy, can restore function, reduce pain, and may potentially have an opioid-sparing effect. Technical expertise in nerve and anatomy is needed for the use of this technique. This review article aims to provide updated information on some invasive intervention techniques in pain management.

Pure Platelet and Leukocyte-Platelet-Rich Plasma for Regenerative Medicine in Orthopedics-Time- and Preparation-Dependent Release of Growth Factors and Effects on Synovial Fibroblasts: A Comparative Analysis

Intra-articular injections of autologous platelet concentrates are considered capable to enhance the healing of cartilage lesions, alleviate joint inflammation, and relieve other musculoskeletal pathological conditions. The aim of this study was to analyze the soluble fractions obtained from platelet-rich plasma (pure- and leukocyte-PRP) to compare time- and preparation-dependent modifications of growth factor concentrations and the supporting activity of the two preparations on synovial fibroblast growth and hyaluronic acid (HA) production in vitro. The release kinetics of FGF-2, SDF-1, VEGF, HGF, EGF, PD GF-AB/BB, IGF-1, VCAM-1, and TGF-β isoforms were followed up to 168 h after PRP activation, and their amounts were determined by multiplex-beads immunoassay. Synovial cell growth and supernatant HA production were respectively analyzed by Alamar Blue assay and ELISA. Time-dependent modifications grouped molecules in three peculiar patterns: one reaching the highest concentrations within 18 h and decreasing afterwards, another progressively increasing up to 168 h, and the last peaking at the central time points. Synovial fibroblast growth in response to L-PRP and P-PRP revealed differences over time and among added concentrations. Both preparations displayed a preserved supporting capacity of HA synthesis.

Clinical and Functional Outcome of Meniscal Injuries Treated with Platelet-Rich Plasma: A Single-Center Case Series

Meniscal injuries are among the most frequently encountered conditions in the knee joint. Therapeutic approaches are diverse and are largely dependent on the extent and location of the injury. The purpose of this study was to describe the clinical and functional outcomes of an intraarticular and percutaneous platelet-rich plasma (PRP) injection regime in patients with stable meniscal injuries. Demographics, the type of tear, affected knee, surgical procedure, type of intervention, follow-up period, and outcomes were recorded in all cases. Patient-reported outcome measures included the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity level scale. Overall patient satisfaction, quality of life, and pain intensity were also assessed. A total of 38 cases (8 females) had sustained a stable meniscal lesion (32 medial, 6 lateral) and met the inclusion criteria. All of them received three intraarticular and percutaneous PRP injections. Patients receiving the PRP injection regime reported clinically (p = 0.000) and functionally (p = 0.000 and p = 0.001) significant improvement in all outcome measures during this interval. All patients reported they were very satisfied or satisfied with the outcome. The results of this study suggest that the treatment of stable meniscal injuries with percutaneous-intraarticular PRP injections can achieve a significant clinical and functional improvement.

Case report: pulsed radiofrequency surgery combined with platelet-rich plasma injection in the treatment of supraspinatus injury

RATIONALE

The shoulder joint is the most movable joint of the human body, and the incidence of aseptic inflammation of the muscles and tendons around the shoulder joint and acute and chronic muscle injuries is relatively high. Pulsed radiofrequency neuromodulation technology is gradually being used in shoulder joint diseases. Platelet-rich plasma (PRP) is a high-power platelet plasma solution obtained by centrifugation of autologous blood. Platelet cells contain many growth factors that promote tissue repair.

PATIENT CONCERNS

Shoulder soreness, limited movement of the shoulder joint, abduction of the upper limbs, and aggravation of pain during flat lifting. The pain radiates to the deltoid muscle stop and forearm.

INTERVENTIONS

In this study, radiofrequency pulses combined with PRP were used to treat supraspinatus muscle injury and explore new methods for the treatment of shoulder joint muscle and tendon injuries represented by supraspinatus muscle injury.

DIAGNOSIS

We reported 4 patients with supraspinatus injury who received radiofrequency pulse combined with PRP treatment in our hospital.

OUTCOMES

After treatment, the patients were followed up at the first month, the third month, and the sixth month, and the Constant-Murley shoulder score and visual analog scale were used to comprehensively evaluate the postoperative improvement of the patients. There was no significant increase in postoperative pain, the Constant-Murley shoulder Score was significantly increased, the range of movement of the shoulder joint was significantly improved, and there were no postoperative complications.

LESSONS

The combined application of the 2 treatments can make full use of the analgesic effect of pulsed radiofrequency technology and the repairing effect of PRP, and can maximize the advantages of the 2 more advanced treatment methods in the field of minimally invasive.

Fractional Carbon Dioxide Laser or Erbium:Yttrium-Aluminum-Garnet Laser Assisted by Topical Application/Intradermal Injection of Platelet-Rich Plasma for Postacne Scars

BACKGROUND

Fractional carbon dioxide or erbium:yttrium-aluminum-garnet (YAG) laser combined with platelet-rich plasma has been used for postacne scars. Nevertheless, there is limited evidence on its use because of the small size of relevant studies. This study aims to evaluate the efficacy of platelet-rich plasma-assisted laser for postacne scars.

METHODS

Randomized controlled trials comparing carbon dioxide or erbium:YAG laser combined with platelet-rich plasma to laser alone were searched for using the PubMed, Embase, Web of Science, Cochrane Library, and Google Scholar databases.

RESULTS

In total, 13 studies involving 672 cases were included. The overall degree of clinical improvement favored platelet-rich plasma combined with carbon dioxide laser (mean difference, 0.55; 95 percent CI, 0.40 to 0.70) or erbium:YAG laser (mean difference, 0.63; 95 percent CI, 0.31 to 0.96). Notably, the use of carbon dioxide laser combined with platelet-rich plasma was more effective in both greater than 50 percent improvement of acne scars (OR, 1.63; 95 percent CI, 1.10 to 2.42) and greater than 75 percent improvement of acne scars (OR, 2.78; 95 percent CI, 1.75 to 4.42), compared with laser alone. Erbium:YAG laser combined with platelet-rich plasma was more effective in greater than 75 percent improvement of acne scars compared with laser alone (OR, 3.45; 95 percent CI, 1.31 to 9.05). Moreover, patient satisfaction was significantly higher with platelet-rich plasma combined with carbon dioxide laser (OR, 2.98; 95 percent CI, 1.72 to 5.16) or erbium:YAG laser (OR, 2.88; 95 percent CI, 1.33 to 6.21) compared to laser alone.

CONCLUSION

This meta-analysis provides reliable evidence that fractional carbon dioxide or erbium:YAG laser combined with platelet-rich plasma is an effective and safe combination therapy for postacne scars.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

Efficacy of platelet-rich plasma and plasma for symptomatic treatment of knee osteoarthritis: a double-blinded placebo-controlled randomized clinical trial

Background

Platelet-rich plasma (PRP) has a still conflicting efficacy for knee osteoarthritis (KOA) and might be a minimally invasive and safe treatment alternative. The potential benefit of only plasma (non-enriched) has never been investigated. Our aim was to evaluate the efficacy of intra-articular platelet-rich plasma (PRP) and plasma to improve pain and function in participants with KOA over 24 weeks.

Methods

Randomized, double-blind, placebo-controlled trial with 3 groups (n = 62): PRP (n = 20), plasma (n = 21) and saline (n = 21). Two ultrasound-guided knee injections were performed with a 2-week interval. The primary outcome was visual analog scale 0-10 cm (VAS) for overall pain at week 24, with intermediate assessments at weeks 6 and 12. Main secondary outcomes were: KOOS, OMERACT-OARSI criteria and TUGT.

Results

At baseline, 92% of participants were female, with a mean age of 65 years, mean BMI of 28.0 Kg/m²and mean VAS pain of 6.2 cm. Change in pain from baseline at week 24 were -2.9 (SD 2.5), -2.4 (SD 2.5) and -3.5 cm (SD 3.3) for PRP, plasma and saline, respectively (p intergroup = 0.499). There were no differences between the three groups at weeks 6 and 12. Similarly, there were no differences between groups regarding secondary outcomes. The PRP group showed higher frequency of adverse events (65% versus 24% and 33% for plasma and saline, respectively, p = 0.02), mostly mild transitory increase in pain.

Conclusions

PRP and plasma were not superior to placebo for pain and function improvement in KOA over 24 weeks. The PRP group had a higher frequency of mild transitory increase in pain.

Trial registration

ClinicalTrials.gov, NCT03138317, 03/05/2017.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04706-7.

Evidence for the use of PRP in chronic midsubstance Achilles tendinopathy: A systematic review with meta-analysis

BACKGROUND

Platelet-rich plasma (PRP) injections have been proposed as an additional therapy in the treatment of chronic midsubstance Achilles tendinopathy (AT). The use of PRP injections as pharmacological treatment added to a conservative approach has gained growing interest, but the efficacy remains highly debated. The varying methodological quality of the available studies may contribute to these contradictory results. The aim of this systematic review with meta-analysis was to establish the existing evidence of PRP injections for chronic midsubstance AT on the functional outcome, with a risk of bias assessment of each included study.

METHODS

According to the PRISMA guidelines systematic searches were performed in Embase, the Cochrane library and Pubmed on June 12, 2020 for relevant literature. Only clinical trials comparing PRP injections with placebo, additional to an eccentric training program, in midsubstance AT were included. The primary outcome was Victorian Institute of Sport Assessment - Achilles (VISA-A) score at 3, 6 and 12 months post-injection. Risk of bias was assessed using the Cochrane risk-of-bias tool for randomized trials (Rob 2). As secondary outcome we assessed reported changes in tendon structure after PRP injections.

RESULTS

A total of 367 studies were identified with the initial database search. Finally, four randomized controlled trials (RCTs) met inclusion criteria for systematic review and meta-analysis with data of 170 patients available for pooling. Results showed no difference in clinical outcome between the PRP and placebo group at different points in time using the VISA-A score as outcome parameter (3 months 0.23 (CI -0.45, 0.91); 6 months 0.83 (CI -0.26, 1.92); 12 months 0.83 (CI -0.77, 2.44)). The bias analysis showed a low or intermediate risk of bias profile for all studies which supports the good methodological quality of each included article. Finally, it is unclear whether PRP injections cause an improvement in tendon structure. However, no direct relationship between tendon structure and clinical presentation of AT could be found.

CONCLUSION

PRP has no clear additional value in management of chronic midsubstance Achilles tendinopathy and therefore should not be used as a first-line treatment option.

Platelet-Rich Plasma Versus Corticosteroids for the Treatment of Plantar Fasciitis: A Systematic Review and Meta-analysis

BACKGROUND

Plantar fasciitis is a common cause of heel pain. Corticosteroid injections are commonly used and proven to be effective, and lately platelet-rich plasma (PRP) has been used with mixed results.

PURPOSE

To perform a systematic review and meta-analysis comparing intralesional injections of PRP and steroid infiltration.

STUDY DESIGN

Systematic review and meta-analysis.

METHODS

A systematic review of Medline, Embase, Scopus, and Google Scholar including all level 1 and 2 studies from 2010 to 2019 was perfomed. American Orthopaedic Foot and Ankle Society and visual analog scale for pain scores were used as outcome variables. Publication bias and risk of bias was assessed with the Cochrane Collaboration tools. The Grading of Recommendations, Assessment, Development and Evaluations system was used to assess the quality of the body of evidence. Heterogeneity was assessed with χ² and I² statistics.

RESULTS

Fifteen studies were included in the analysis. Nine studies had a high risk of bias. There was 1 study with high quality, 9 with moderate, 2 studies with low, and 3 with very low quality. The pooled estimate for the American Orthopaedic Foot and Ankle Society score demonstrated nonsignificant differences at 1 month (P = .4) and 3 months (P = .076). At 6 months (P = .009) and 12 months (P = .009), it indicated significant differences in favor of PRP. The pooled estimate for visual analog scale demonstrated nonsignificant differences at 1 month (P = .653). At 3 months (P = .0001), 6 months (P = .002), and 12 months (P = .019), it yielded significant differences in favor of PRP.

CONCLUSION

The results of this systematic review and meta-analysis suggest that PRP is superior to corticosteroid injections for pain control at 3 months and lasts up to 1 year. In the short term, there is no advantage of corticosteroid infiltration. However, the low study quality, high risk of bias, and different protocols for PRP preparation reduce the internal and external validity of these findings, and these results must be viewed with caution.

A Critical Overview of the Use of Platelet-Rich Plasma in Equine Medicine Over the Last Decade

In the 1990s, the role of platelets in inflammation and tissue healing was finally recognized. Since then, the clinical use of platelet-derived products (hemocomponents), such as, platelet-rich plasma (PRP), markedly increased. The promise of a more economical option of a disease-modifying treatment led to the intensive and continuous research of PRP products and to its widespread clinical use. A number of protocols and commercial kits have been developed with the intention of creating a more practical and reliable option for clinical use in equine patients. Still, the direct comparison between studies is particularly challenging due to the lack of standardization on the preparation methods and product composition. The incomplete reports on PRP cellular concentration and the poorly designed in vivo studies are additional matters that contest the clinical efficiency of this biomaterial. To overcome such challenges, several in vitro and in vivo studies have been proposed. Specifically, experiments have greatly focused in protocol optimization and its effect in different tissues. Additionally, in vivo studies have proposed different biological products envisioning the upgrade of the anti-inflammatory cytokines trusting to increase its anti-inflammatory effect. The individual variability and health status of the animal, type of tissue and condition treated, and protocol implemented are known to influence on the product's cell and cytokine composition. Such variability is a main clinical concern once it can potentially influence on PRP's therapeutic effects. Thus, lack of qualitative and quantitative evidence-based data supporting PRP's clinical use persists, despite of the numerous studies intended to accomplish this purpose. This narrative review aims to critically evaluate the main research published in the past decade and how it can potentially impact the clinical use of PRP.

Immunoglobulin G in Platelet-Derived Wound Healing Factors

We intended to reformulate an existing platelet-derived wound healing formula to target each phase of the healing wound with the appropriate phase-specific molecules. A decreased perfusion of the skin, often associated with conditions such as thalassemia, sickle cell disease, diabetes mellitus, and chronic vascular disease, is the most common etiology of cutaneous ulcers and chronic wounds. We had previously shown that a PDWHF topically applied to a chronic nonhealing ulcer of a β-thalassemia homozygote stimulated and accelerated closure of the wound. The PDWHF was prepared from a pooled platelet concentrate of a matching blood group, consisting of a combination of platelet α-granule-derived factors. Processing of the apheresis-pooled platelets yielded various amounts of proteins (3.36 g/mL ± 0.25 (SD) (N = 10)) by the better lysis buffer method. Immunoglobulin G was found to be the most abundant α-granule-secreted protein. Equally broad quantities of the IgG (10.76 ± 12.66% (SD) (N = 10)) and IgG/albumin ratios (0.6 ± 0.4 (SD) (N = 10)) were quantified. We have developed a method using a reformulated lysis buffer followed by size exclusion chromatography and affinity chromatography to extract, identify, quantify, and purify IgG from activated platelets. IgG purification was confirmed by Western blot and flow cytometry. It was thought unlikely that the platelet IgG could be accounted for by adsorption of plasma protein, though the variable quantities could account for diversity in wound healing rates. The IgG could protect the wound even from subclinical infections and functionally advance healing. It may be useful in the management of skin ulcers in the early phase of wound healing.

Regenerative Injectable Therapies: Current Evidence

Regenerative medicine is a growing field of musculoskeletal treatments that focuses on amplifying the body's natural healing properties to improve function and pain after injury. Regenerative treatments are applied locally at the site of injury and work though different mechanisms, some of which are unexplained at this time. Current evidence demonstrates benefit for certain regenerative treatments, but further standardization of treatments and additional studies are required to provide additional data to support specific regenerative treatments. This review seeks to explore the evidence and discuss appropriate use of the most common regenerative treatments including platelet-rich plasma, prolotherapy, autologous mesenchymal stem cells, human-derived allograft products, and saline.

Systematic Review and Meta-Analysis of Nonoperative Platelet-Rich Plasma Shoulder Injections for Rotator Cuff Pathology

BACKGROUND

Platelet-rich plasma (PRP) injections have been introduced to augment the recovery of patients with shoulder pathology. Although multiple studies have been published, no large-scale trials or meta-analyses have assessed the efficacy of nonoperative shoulder PRP injection.

OBJECTIVE

To assess the efficacy of nonoperative PRP shoulder injection in rotator cuff pathology for pain as measured by the visual analog scale (VAS) and range of motion (ROM).

DESIGN

Two authors independently screened the Medline and Cochrane databases to include prospective studies that reported VAS and ROM outcomes for nonoperative shoulder PRP injections for rotator cuff pathology. Study quality was assessed using the revised Cochrane Collaboration risk-of-bias tool and modified Downs and Black checklist. Subsequent meta-analysis was performed to determine the effect of nonoperative PRP injections on pain and ROM 3 to 12 months after intervention.

RESULTS

Six studies met systematic review criteria. The included studies used different PRP formulations (concentration, leukocyte count), injection protocols (approach, injection number), and varied study designs. Three studies concluded that PRP provided no significant benefit for pain and ROM when compared to physical therapy. Within-group meta-analysis of six fairly heterogeneous studies (I² 77.8%) demonstrated a statistically significant (P < .001) improvement in pain 3 to 12 months after PRP injection. Within-group meta-analysis for four studies for shoulder flexion and abduction was found to be too heterogeneous to derive meaningful results.

CONCLUSION

There is a limited quantity of high-quality studies that assess the efficacy of nonoperative PRP shoulder injection for pain and ROM. Systematic review of PRP injections did not demonstrate an improvement in pain or ROM compared to physical therapy. Although within-group meta-analysis of nonoperative PRP statistically showed that nonoperative PRP improved pain, the lack of adequate negative controls precludes the ability to conclude whether improvements were due to natural recovery or nonoperative PRP.

Considerations for Clinical Use of Concentrated Growth Factor in Maxillofacial Regenerative Medicine

Different strategies have been utilized to facilitate mineralized/soft tissues. Concentrated growth factor (CGF) emerges as a promising biomaterial for regenerative therapy due to high levels of platelets, growth factors, and nucleated cells entrapped in the fibrin scaffold. This review aimed to collect extensive studies on CGF used in maxillofacial regenerative medicine, discussing current obstacles, and expressing some considerations of CGF use. Articles were retrieved systematically without time limitation. In total, 27 human studies were included and separated accordingly. In general, CGF has been most evaluated in implant related therapy and maxillofacial bone regeneration where a majority of articles have revealed favorable outcomes. Little studies have supported the effects on improving probing periodontal depth reductions and clinical attachment level gains for intrabony and furcation defect regeneration. Very little data with high-level evidence was available directly to investigate its effects on the soft tissue regeneration and postoperative complications reduction. The evidence supporting the clinical efficacy of CGF in maxillofacial regenerative medicine is limited. Some conflicting results are worrisome. In addition, the characterization of CGF preparation protocols and CGF's components was not performed in most studies. Further studies should make a consensus on standardized end-product of CGF including characterization of protocols and optimal ratio of CGF' components. Defined algorithms and evidence-based protocols for the clinical use of CGF should be also available.

Biological Basis of Treatments of Acute Muscle Injuries: A Short Review

Muscle strains occur frequently in recreational and professional sports. This article considers various treatment options in a biological context and reviews evidence of their efficacy. Treatments reviewed include the PRICE principle (P: rotection, R: est, I: ce, C: ompression, E: levation), early mobilization, physical therapy, hematoma aspiration, platelet-rich plasma injections, use of nonsteroidal anti-inflammatory drugs, corticosteroids, and local anesthetics, cellular therapies, and surgery.

Platelet-rich plasma (PRP) as therapy for cartilage, tendon and muscle damage - German working group position statement

Purpose

Platelet rich plasma (PRP) is widely used in orthopaedics, but is still heavily debated. Therefore, a survey among the German “Working Group for Clinical Tissue Regeneration” of the German Society of Orthopaedics and Traumatology was conducted to achieve a consensus about the current therapeutical potential of PRP.

Methods

A first survey (n = 65 experts, all orthopaedic/trauma surgeons) was conducted (n = 13 questions). Following, a second round (n = 40 experts) was conducted with 31 questions to achieve consensus in 5 categories: three most common indications, PRP application, future research areas.

Results

Therapeutic PRP application was regarded as useful (89%), possibly even more important in the future (90%). Most common indications were tendon pathologies (77%), osteoarthritis (OA) (68%), muscle injuries (57%) and cartilage damage (51%). Consensus was reached in 16/31 statements. The application of PRP for early knee OA (Kellgren-Lawrence grade II) was regarded as potentially useful, as well as for acute and chronic tendinopathies. For chronic lesions (cartilage, tendons), multiple injections (2–4) were seen preferable to singular injections. However, no sufficient data exists on the time interval between the injections. Standardization of PRP preparation, application, frequency, as well as determining the range of indication is strongly recommended.

Conclusions

There is a need of further standardization of the PRP preparation methods, indication and application protocols for knee OA and other indications, which must be further evaluated in basic science studies and randomized controlled clinical trials.

Level of evidence

Consensus of expert opinion, Level V.

Platelet Concentrates in Musculoskeletal Medicine

Platelet concentrates (PCs), mostly represented by platelet-rich plasma (PRP) and platelet-rich fibrin (PRF) are autologous biological blood-derived products that may combine plasma/platelet-derived bioactive components, together with fibrin-forming protein able to create a natural three-dimensional scaffold. These types of products are safely used in clinical applications due to the autologous-derived source and the minimally invasive application procedure. In this narrative review, we focus on three main topics concerning the use of platelet concentrate for treating musculoskeletal conditions: (a) the different procedures to prepare PCs, (b) the composition of PCs that is related to the type of methodological procedure adopted and (c) the clinical application in musculoskeletal medicine, efficacy and main limits of the different studies.