Percutaneous injections of Platelet rich plasma for treatment of intrasubstance meniscal lesions

Degenerative Meniscus Tears Treated Nonoperatively With Platelet-Rich Plasma Yield Variable Clinical and Imaging Outcomes: A Systematic Review

Purpose

To perform a systematic review on clinical and radiologic outcomes for meniscus tears treated nonoperatively with platelet-rich plasma (PRP).

Methods

A literature search was performed according to the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines using keywords and Boolean operators in SCOPUS, PubMed, Medline, and the Cochrane Central Register for Controlled Trials in April 2023. Inclusion criteria were limited to Level I to IV human studies reporting on outcomes of meniscus tears treated nonoperatively with PRP.

Results

A total of 6 studies, consisting of 184 patients, were identified. There was 1 Level I study and 5 Level IV studies. Mean patient age was 47.8 ± 7.9 years, with 62% (n = 114/184) being female. The medial meniscus was treated in 95.7% (n = 157/164) of patients. Mean follow-up ranged from 75.9 days to 31.9 months. Meniscus tears were generally described as chronic, degenerative, or intrasubstance. In 4 studies, magnetic resonance imaging revealed variable improvement in meniscus grade with complete healing in 0% to 44% of patients and partial healing in 0% to 40% of patients. Four of 5 studies reported significant statistical improvement in pain from baseline to final follow-up. Studies reporting on clinical outcomes showed significant improvements Lysholm score (2 studies), Knee injury and Osteoarthritis Outcome Score total score (2 studies), and Tegner score (1 study). Successful return to sport occurred in 60% to 100% of patients. Two studies reported that most patients were either very satisfied or satisfied following treatment.

Conclusions

The use of PRP injections for the treatment of meniscus tears led to variable results based on postoperative magnetic resonance evaluation and improvements in clinical outcomes, although the clinical significance remains unclear. The heterogeneity of PRP protocols, short-term follow-up, and lack of comparative studies limit findings.

Level of Evidence

Level IV, systematic review of Level I to IV studies.

Most Publications Regarding Platelet-Rich Plasma Use in the Knee Are From Asia, Investigate Injection for Osteoarthritis, and Show Outcome Improvement: A Scoping Review

PURPOSE

To evaluate and synthesize the available literature related to platelet-rich plasma (PRP) treatment of knee pathologies and to provide recommendations to inform future research in the field.

METHODS

PubMed, CINAHL, and Scopus databases were queried on October 6, 2023. All identified citations were collated and uploaded into Covidence for screening and data extraction. Studies were included if they were human studies published in English with adult cohorts that received PRP as a procedural injection or surgical augmentation for knee pathologies with patient-reported outcome measures (PROMs) and level of evidence Levels I-IV.

RESULTS

Our search yielded 2,615 studies, of which 155 studies from 2006 to 2023 met the inclusion criteria. Median follow-up was 9 months (±11.2 months). Most studies (75.5%) characterized the leukocyte content of PRP, although most studies (86%) did not use a comprehensive classification scheme. In addition, most studies were from Asia (50%) and Europe (32%) and were from a single center (96%). In terms of treatment, 74% of studies examined PRP as a procedural injection, whereas 26% examined PRP as an augmentation. Most studies (68%) examined treatment of knee osteoarthritis. Many studies (83%) documented significant improvements in PROMs, including 93% of Level III/IV evidence studies and 72% of Level I/II evidence studies, although most studies (70%) failed to include minimal clinically important difference values. The visual analog scale was the most-used PROM (58% of studies), whereas the Short Form Health Survey 36-item was the least-used PROM (5% of studies).

CONCLUSIONS

Most published investigations of knee PRP are performed in Asia, investigate procedural injection for osteoarthritis, and show significant outcome improvements. In addition, this review highlights the need for better classification of PRP formulations.

LEVEL OF EVIDENCE

Level IV, scoping Review of level I-IV studies.

Utility of Platelet-Rich Plasma Therapy in the Management of Meniscus Injuries: A narrative review

Menisci are crucial for knee joint functions and meniscal tears are common injuries, especially in sports activities. Platelet-rich plasma (PRP), which enhances healing, has emerged as a promising additive treatment for meniscus injuries, utilizing the regenerative properties of platelets and growth factors for improved clinical outcomes. In studies with a follow-up period of less than one year, the use of platelet-rich plasma (PRP) therapy for meniscus injuries showed significant improvements in knee symptoms and daily activity. Patients experienced enhanced outcomes in terms of pain reduction and increased sports activity, with MRI scans indicating stable meniscus conditions after six months. Studies with a follow-up of more than one year, however, did not find significant differences between groups treated with PRP and groups not treated with PRP in terms of various outcome measures, including pain and knee function. The vascularization of the menisci is vital for their proper function, and insufficient blood supply can affect healing of meniscal injuries. PRP therapy is used to enhance meniscal healing by introducing growth factors and anti-inflammatory agents. PRP therapy may enable athletes with meniscal tears to return to sports more quickly and has less rehabilitation duration. While PRP seems promising as an alternative to failed treatment or as an adjunct to treatment in the short term, its long-term effectiveness remains inconclusive. Patient preferences, commitment to therapy rehabilitation, and cost should all be considered on an individual basis.

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.

Nonoperative and Operative Soft-Tissue and Cartilage Regeneration and Orthopaedic Biologics of the Knee: An Orthoregeneration Network (ON) Foundation Review

Orthoregeneration is defined as a solution for orthopedic conditions that harnesses the benefits of biology to improve healing, reduce pain, improve function, and optimally, provide an environment for tissue regeneration. Options include: drugs, surgical intervention, scaffolds, biologics as a product of cells, and physical and electro-magnetic stimuli. The goal of regenerative medicine is to enhance the healing of tissue after musculoskeletal injuries as both isolated treatment and adjunct to surgical management, using novel therapies to improve recovery and outcomes. Various orthopaedic biologics (orthobiologics) have been investigated for the treatment of pathology involving the knee, including symptomatic osteoarthritis and chondral injuries, as well as injuries to tendon, meniscus, and ligament, including the anterior cruciate ligament. Promising and established treatment modalities include hyaluronic acid (HA) in liquid or scaffold form; platelet-rich plasma (PRP); bone marrow aspirate (BMA) comprising mesenchymal stromal cells (MSCs), hematopoietic stem cells, endothelial progenitor cells, and growth factors; connective tissue progenitor cells (CTPs) including adipose-derived mesenchymal stem cells (AD-MSCs) and tendon-derived stem cells (TDSCs); matrix cell-based therapy including autologous chondrocytes or allograft; vitamin D; and fibrin clot. Future investigations should standardize solution preparations, because inconsistent results reported may be due to heterogeneity of HA, PRP, BMAC, or MSC preparations and regimens, which may inhibit meaningful comparison between studies to determine the true efficacy and safety for each treatment.

Efficacy of Autologous Platelet-Rich Plasma Injections for Grade 3 Symptomatic Degenerative Meniscal Lesions: A 1-Year Follow-up Prospective Study

BACKGROUND

Platelet-rich plasma (PRP) injections have been proposed as a biologic option to provide symptomatic relief and delay surgery in patients with degenerative joint disease of osteoarthritis (OA). The efficacy of autologous PRP on symptomatic degenerative meniscal lesions (DMLs) has never been investigated.

HYPOTHESIS

We hypothesized that patients with symptomatic DMLs without OA undergoing autologous PRP injections experience a significant clinical improvement at 12 months.

STUDY DESIGN

Prospective case series.

LEVEL OF EVIDENCE

Level 4.

METHODS

A total of 69 patients with symptomatic DMLs without radiographic evidence of knee OA (Kellgren-Lawrence radiographic grading scale 0-1) received 4 autologous PRP injections once a week. Patients were prospectively evaluated before the injection and then at 1, 3, 6, and 12 months. Evaluation was based on Lysholm knee scoring scale (primary outcome), Western Ontario and McMaster Universities Arthritis Index (WOMAC), Tegner activity scale, and visual analogue scale scores.

RESULTS

Patients treated with PRP injections demonstrated an improving knee function and symptoms over the duration of the study. A significant improvement from baseline to 12 months was observed in all the outcome measures, and no patients experienced failure or required surgery during the follow-up. Patients younger than 50 years reported lower subjective level of pain and higher Tegner activity scale at baseline and had significantly better Lysholm knee scoring scale (P = 0.03) and WOMAC (P = 0.03) scores at 6 months, as well as better range of motion at 3, 6, and 12 months (P < 0.001). Thirty-three (47.8%) patients were very satisfied, 26 (37.7%) satisfied, 8 (11.6%) partially satisfied, and 2 (2.9 %) not satisfied, with 62 (89.8%) patients willing to repeat the same treatment. No patient was lost to follow-up and no patient experienced adverse reaction, infection, failure, recurrence or underwent further surgery.

CONCLUSION

PRP injections provide short-term benefits in symptomatic DMLs. Although promising results were evident at 12 months, this is a preliminary study and no definitive recommendation can be made based, for example, on longer follow-up.

CLINICAL RELEVANCE

This research supports the use of autologous PRP injections for symptomatic DMLs.

Biologic Augmentation Reduces the Failure Rate of Meniscal Repair: A Systematic Review and Meta-analysis

Background

Clinical results after isolated meniscal repair are not always satisfactory, with an overall failure rate of around 25%. To improve the success rate of meniscal repair, different biologic augmentation techniques have been introduced in clinical practice, but their real efficacy is still controversial.

Purpose/Hypothesis

To evaluate the safety, clinical results, and failure rate of biologic augmentation techniques for meniscal repair. The hypothesis was that biologic augmentation would improve the results of meniscal repair.

Study Design

Systematic review and meta-analysis of comparative studies.

Methods

A systematic review of the literature was performed in March 2020 of 3 electronic databases (PubMed, Scopus, and the Cochrane Library) regarding meniscal repair combined with biologic augmentation techniques. Articles combining biologic augmentation with other surgical procedures besides meniscal suture were excluded. The quality of the included studies was assessed using a modified Coleman Methodology Score, and the risk of bias was evaluated using the ROBINS-I (Risk of Bias in Non-randomized Studies of Interventions) and the RoB 2.0 (Revised Tool for Risk of Bias in Randomized Trials) for nonrandomized and randomized controlled trials, respectively.

Results

A total of 11 studies were included in the qualitative analysis: platelet-rich plasma (PRP) augmentation in 6 comparatives studies, fibrin clot augmentation in 2 case series, and mesenchymal stem cells augmentation in 2 case series and 1 case report. One severe adverse event of septic arthritis was reported for PRP 1 month after surgery. The quality of evidence evaluated with the modified Coleman Methodology Score was low overall. Five studies reporting on 286 patients (111 PRP augmentation, 175 control) were included in the quantitative synthesis. A significantly lower risk of failure was documented in the PRP augmentation group as compared with the control group: 9.9% (4.5%-19.1%) versus 25.7% (12.7%-38.7%) (P < .0005).

Conclusion

The literature on biologic meniscal augmentation is recent and scarce. Only a few comparative trials are available, all focusing on the potential of PRP. The meta-analysis documented that PRP is safe and useful in improving the survival rate, with a 9.9% rate of failure versus 25.7% for the control group. Further high-level studies are needed to confirm these findings and identify the most effective biologic augmentation strategy to improve the outcome of meniscal repair.

Radiological and functional outcomes of ultrasound-guided PRP injections in intrasubstance meniscal degenerations

AIM

This retrospective study is aimed to analyze the effect of ultrasound-guided platelet-rich plasma (PRP) injections on grade 2 intrasubstance meniscal degenerations (IMDs).

MATERIALS AND METHODS

Fifteen patients who underwent PRP injections for symptomatic grade 2 meniscal lesions were included in the study. All injections were performed with ultrasound in the degenerated menisci. Patients were evaluated with Lysholm score and magnetic resonance imaging (MRI) before the injection and after a mean of 32-month follow-up. T2-weighted MRI images were evaluated on sagittal by two authors as double-blind.

RESULTS

Lysholm score was found to be statistically significantly increased, and in 67% of the patients, grade 2 degenerations were improved to grade 1.

CONCLUSION

Intra-meniscal PRP injection under ultrasonography guidance provides good functional scores and radiological improvement in the patients with IMD.

Degenerative Meniscus Lesions: An Expert Consensus Statement Using the Modified Delphi Technique

PURPOSE

The purpose of this study was to perform an evidence-based, expert consensus survey using the Delphi panel methodology to develop recommendations for the treatment of degenerative meniscus tears.

METHODS

Twenty panel members were asked to respond to 10 open-ended questions in rounds 1 and 2. The results of the first 2 rounds served to develop a Likert-style questionnaire for round 3. In round 4, the panel members outside consensus were contacted and asked to either change their score in view of the group's response or argue their case. The level of agreement for round 4 was defined as 80%.

RESULTS

There was 100% agreement on the following items: insidious onset, physiological part of aging, tears often multiplanar, not all tears cause symptoms, outcomes depend on degree of osteoarthritis, obesity is a predictor of poor outcome, and younger patients (<50 years) have better outcomes. There was between 90% and 100% agreement on the following items: tears are nontraumatic, radiographs should be weightbearing, initial treatment should be conservative, platelet-rich plasma is not a good option, repairable and peripheral tears should be repaired, microfracture is not a good option for chondral defects, the majority of patients obtain significant improvement and decrease in pain with surgery but results are variable, short-term symptoms have better outcomes, and malalignment and root tears have poor outcomes.

CONCLUSIONS

This consensus statement agreed that degenerative meniscus tears are a normal part of aging. Not all tears cause symptoms and, when symptomatic, they should initially be treated nonoperatively. Repairable tears should be repaired. The outcome of arthroscopic partial meniscectomy depends on the degree of osteoarthritis, the character of the meniscus lesion, the degree of loss of joint space, the amount of malalignment, and obesity. The majority of patients had significant improvement, but younger patients and patients with short-term symptoms have better outcomes.

LEVEL OF EVIDENCE

Level V - expert opinion.

Treatment of degenerative meniscal tear with intrameniscal injection of platelets rich plasma

PURPOSE

The purpose of this retrospective study was to describe our preliminary results of intra-meniscal administration of platelet rich plasma (PRP) in patients with degenerative meniscal tears of the knee.

MATERIAL AND METHOD

Ten patients with degenerative meniscal tears according to the Stoller classification and without knee osteoarthritis were included. There were 7 men and 3 women with a mean age of 40.4±13.6 [SD] years (range: 18-59 years). Patients were prospectively assessed at baseline and 3- and 6-months after intra meniscal PRP administration. Evaluation included the knee injury and osteoarthritis outcome score (KOOS), pain visual analog scale, and return to competition and training. MRI follow-up was performed 6 months after PRP administration. Adverse events were recorded.

RESULTS

Volume of injected PRP was standardized to 4.0mL. Adverse events during PRP administration was moderate pain in 8 patients (8/10; 80%). Mean KOOS total score significantly improved from 56.6±15.7 (SD) to 72.7±18.5 (SD) (P=0.0007). All six patients practicing sports regularly were able to recover competition or training. In seven patients who underwent MRI follow-up at 6 months, MRI showed stability of the meniscal tears and similar Stoller grades.

CONCLUSION

Intra-meniscal administration of PRP under ultrasound guidance directly into meniscal degenerative lesions is feasible and safe. Further randomized controlled studies are needed to definitely confirm the effectiveness of this procedure.

Platelet-Rich Fibrin and its Emerging Therapeutic Benefits for Musculoskeletal Injury Treatment

New therapies that accelerate musculoskeletal tissue recovery are highly desirable. Platelet-rich fibrin (PRF) is a leukocyte- and platelet-rich fibrin biomaterial that acts as a binding site for both platelets and growth factors. Through increasing the local concentration of growth factors at specific tissues, PRF promotes tissue regeneration. PRF has been frequently used in combination with bone graft materials to reduce healing times and promote bone regeneration during maxillofacial surgery. However, its benefits during muscle repair and recovery are less well-documented. Here, we perform a narrative review on PRF therapies and muscle injuries to ascertain its beneficial effects. We reviewed the factors that contribute to the biological activity of PRF and the published pre-clinical and clinical evidence to support its emerging use in musculoskeletal therapy. We include in vitro studies, in vivo animal studies and clinical articles highlighting both the success and failures of PRF treatment. PRF can promote the healing process when used in a range of orthopaedic and sports-related injuries. These include cartilage repair, rotator cuff surgery and anterior cruciate ligament surgery. However, conflicting data for these benefits have been reported, most likely due to inconsistencies in both PRF preparation protocols and dosing regimens. Despite this, the literature generally supports the use of PRF as a beneficial adjuvant for a range of chronic muscle, tendon, bone or other soft tissue injuries. Further clinical trials to confirm these benefits require consistency in PRF preparation and the classification of a successful clinical outcome to fully harness its potential.

Platelet-rich plasma: myth or reality?

Platelet-rich plasma (PRP) is a preparation for therapeutic purposes that is increasingly accepted for various musculoskeletal disorders, due to its theoretical potential to repair tissues with poor healing capacity. Several randomised clinical trials have investigated the capacity of PRP to repair tendons, ligaments, muscles and cartilage, and to date there is level 1a evidence to support its use for lateral epicondylitis, osteoarthritis of the knee, plantar fasciitis and rotator cuff tendinopathy; and level 1b for patellar tendinopathy and osteoarthritis of the hip. Retrospective cohort studies and case series describe promising results with PRP for treating other musculoskeletal disorders. Since its side effects are fewer than those of the control groups, the treatment is considered practically harmless and is being increasingly used. Further randomised clinical trials are necessary to establish future indications, and to confirm effectiveness and safety.

A systematic review of the effects of platelet rich plasma on outcomes for patients with knee osteoarthritis and following total knee arthroplasty

INTRODUCTION

Platelet rich plasma (PRP) has been suggested to be effective in the management of knee osteoarthritis. Review of current literature reveals conflicting evidence regarding the benefits of PRP in treating knee OA. Preclinical evidence supports the use of PRP injections to promote a favorable environment for joint tissue healing, targeting not only cartilage but also synovial and meniscal tissues which has a positive effect on delaying the progression of OA. Growth factors found in platelet granules are postulated to influence outcomes in knee OA and after total knee arthroplasty (TKA).

METHODOLOGY

A systematic review of studies investigating the use of PRP in knee osteoarthritis and following TKA, was performed by searching the following databases for randomised clinical trials and pseudo-randomised clinical and comparative trials comparing the use of PRP to treat knee osteoarthritis and following TKA: MedLine, EMBASE, Science Direct, PubMed, and the Cochrane Library. The primary outcomes were patient reported measures including pain (visual analog scale (VAS)), quality of life scores, and knee function.

RESULTS

A total of 2328 participants were analyzed across 17 included studies and pooled results showed a statistically significant reduction in pain in favor of PRP following TKA but not in non-surgical management of knee OA (P < 0.0001 and 0.13 respectively). No clinical benefit of PRP was found on quality of life and knee function (P = 0.07 and 0.05) following TKA, although a statistical improvement in knee function was demonstrated in patients with knee OA after PRP injection (P < 0.0001). There was no statistically significant clinical benefit of PRP on secondary outcomes including wound scores and length of hospital stay (p = 0.33 and 0.31, respectively). There was no statistically significant difference in respect to blood loss and overall symptoms in favor of PRP compared to control group following TKA (p = 0.37).

CONCLUSION

This systematic review demonstrated no long-term statistically significant improvement in patient validated outcomes and secondary outcomes both in patients with knee OA or following TKA for OA. However PRP has been shown to have short to medium-term benefits in pain control after TKA and activities of daily living in patients with OA.

Thrombospondin-1 promotes mesenchymal stromal cell functions via TGFβ and in cooperation with PDGF

Mesenchymal stromal cells (MSC) are characterized by unique tropism for wounded tissues, high differentiating capacity, ability to induce tissue repair, and anti-inflammatory and immunoregulatory activities. This has generated interest in their therapeutic use in severe human conditions as well as in regenerative medicine and tissue engineering. Identification of factors involved in the regulation of MSC proliferation, migration and differentiation could provide insights into the pathophysiological regulation of MSC and be exploited to optimize clinical grade expansion protocols for therapeutic use. Here we identify thrombospondin-1 (TSP-1) as a major regulator of MSC. TSP-1 induced MSC proliferation. This effect was mediated by TSP-1-induced activation of endogenous TGFβ, as shown by the inhibitory effects of anti-TGFβ antibodies and by the lack of activity of TSP-2 - that does not activate TGFβ. Moreover, TSP-1 strongly potentiated the proliferative and migratory activity of PDGF on MSC. TSP-1 directly bound to PDGF, through a site located within the TSP-1 type III repeats, and protected the growth factor from degradation by MSC-derived proteases, hence increasing its stability and bioavailability. The studies presented here identify a more comprehensive picture of the pleiotropic effect of TSP-1 on MSC behavior, setting the basis for further studies aimed at investigating the possible use of PDGF and TSP-1 in the in vitro expansion of MSC for therapeutic applications.

Leukocyte-poor platelet-rich plasma to treat degenerative meniscal tear: A case report

A traumatic and/or degenerative meniscus lesion is thought to be a clinical manifestation of early-onset osteoarthritis (OA), which is a chronic progressive condition that can cause substantial pain and disability. Platelet-rich plasma (PRP) is an emerging treatment option that has been reported to improve healing. Here, we present a case of a 29-year-old woman, with left anterior and medial knee pain, without history of trauma or injury. The patient was managed with leukocyte-poor PRP injections derived from her peripheral blood with high concentrations of platelets, platelet-derived growth factors, and bioactive proteins, with a total follow-up of 30 months. Post-treatment patient was evaluated at every follow-up for improvement using three independent measures, VAS, GROC, and KOOS. There was considerable improvement in the pain symptoms from baseline (VAS: 70 mm; GROC: n/a; and KOOS: 39) to 30 months (VAS: 40 mm; GROC: 5; and KOOS: 63.1) indicating that PRP injections can serve as therapeutic intervention for treatment of pain associated with early onset of OA. To further validate these results, more longitudinal and evidence-based studies are recommended, which may further guide the clinicians to manage early-onset OA with PRP.