Platelet-rich plasma application in chondrogenesis

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

BACKGROUND

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

METHODS

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

DISCUSSION

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

TRIAL REGISTRATION

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

Effects of Temperature and Time on the Denaturation of Transforming Growth Factor Beta-1 and Cytokines from Bovine Platelet-Rich Gel Supernatants

There is a lack of information about transforming growth factor beta-1 (TGF-β1) and cytokines contained in pure platelet-rich plasma (P-PRP) and release from pure-platelet-rich gel supernatants (P-PRGS) might be affected by the temperature and time factors; P-PRP from 6 heifers was activated with calcium gluconate. Thereafter, P-PRG and their supernatants (P-PRGS) were maintained at -80, -20, 4, 21, and 37 °C and collected at 3, 6, 12, 24, 48, 96, 144, 192, 240, and 280 h for subsequent determination of TGF-β1, tumor necrosis factor alfa (TNF-α), interleukin (IL)-2, and IL-6; TGF-β1 concentrations were significantly (p < 0.05) higher in PRGS maintained at 21 and 37 °C when compared to PRGS maintained at 4, -20, and -80 °C; PRGS TNF-α concentrations were not influenced by temperature and time factors. However, PRGS maintained at 4 °C showed significantly (p < 0.05) higher concentrations when compared to PRGS maintained at -20, and -80 °C at 144, and 192 h. IL-6 concentrations were significantly (p < 0.05) higher in PRGS stored at -20, and -80 over the first 48 h and at 10 days when compared to PRGS stored at 4, 21, and 37 °C. These results could suggest that P-PRP/P-PRGS could be maintained and well preserved for at least 12 days at room temperature for clinical use in bovine therapeutic massive protocols.

Exploring Platelet-Rich Plasma Therapy for Knee Osteoarthritis: An In-Depth Analysis

The use of platelet-rich plasma (PRP) in all medical fields is currently gaining popularity (1). PRP is a biological product that can be defined as a segment of the plasma fraction of autologous blood with a platelet concentration level above the baseline (2). The fact that it has uses in tissue regeneration and wound healing has caught the eye of orthopedic surgeons as well, as intra-articular treatments have continued to evolve. Its benefits in the treatment of different osteoarticular pathologies are of great interest in the evolving orthopedic community, targeting mostly knee osteoarthritis, meniscus and ligament injuries (3). The purpose of this review is to update the reader on the current uses of platelet-rich plasma (PRP) in the treatment of knee osteoarthritis pathology and to provide clinical feedback on its uses in the fields of orthopedic and sports medicine practice (4). We proceeded in studying 180 titles and abstracts eligible for inclusion. Compared to alternative treatments, PRP injections greatly improve the function of the knee joint.

Clinical Outcome of Multiple Platelet-Rich Plasma Injection and Correlation with PDGF-BB in the Treatment of Knee Osteoarthritis

(1) Background: Current treatments for knee osteoarthritis (KOA), such as intra-articular corticosteroids or hyaluronic acid (HA) injections, are controversial due to their ineffectiveness in preventing disease progression. Platelet-rich plasma (PRP) has become a promising and possible treatment for KOA. It is thought to enhance articular cartilage regeneration and reduce OA-related impairment. PRP contains growth factors such as PDGF-BB, which stimulates growth and inhibits joint damage. Based on numerous studies, after a certain amount of time, it was found that multiple PRP treatments reduced pain more than a single injection. This study evaluates the efficacy of multiple PRP (m-PRP) injections compared to multiple HA (m-HA) injections for KOA treatment, focusing on their correlation with PDGF-BB levels. (2) Methods: In this single-center, open-label, randomized, comparative clinical trial, 30 KOA patients received m-PRP and m-HA injections. VAS and WOMAC were used to evaluate clinical outcomes and PDGF-BB concentrations. (3) Results: The study analysis revealed a statistically significant reduction in pain indices. In both the m-PRP and m-HA groups after 12 weeks, m-PRP showed superior results. PDGF-BB concentrations also increased, with a strong negative correlation and statistical significance using Spearman's rho. (4) Conclusions: Multiple PRP injections are safe and associated with elevated PDGF-BB, reduced VAS and WOMAC scores, providing the potential for articular cartilage regeneration and inhibiting knee osteoarthritis progression.

Role of platelet rich plasma in management of early knee osteoarthritis pain: A retrospective observational study

Introduction

Knee joint osteoarthritis is a well-known cause of pain and disability in patients above 40 years of age. It is treated by use of non-steroidal inflammatory drugs, corticosteroids, glucosamine, chondroitin sulfate, physiotherapy with limited success. The platelet rich plasma (PRP) contains a large amount of platelet derived growth factors, cytokines and anti-inflammatory molecules which showed promising results in recent studies to relieve pain of knee joint osteoarthritis. The present study aims to determine the efficacy of intraarticular PRP for pain relief and functional improvement in patients with early knee joint osteoarthritis.

Methods

It is a retrospective observation study involving patients who underwent single intraarticular administration of PRP for knee pain with Kellgren-Lawrence (KL) grades I or II knee joint osteoarthritis. The Visual analogue scale (VAS) score and Oxford knee score (OKS) were recorded pre-procedure and at 1- and 6-month post-procedure.

Results

A total of 31 patients (20 females, 11 males) underwent PRP therapy for knee pain (16 kL grade I, 15 kL grade II). The mean age and duration of symptoms were of 53.9 years (range: 79-42 years) and 5.53 ± 2.35 years respectively. There was a significant reduction (p < 0.05) in VAS scores from pre-procedure (68.06 ± 8.33) to post procedure at 1 month (37.74 ± 11.16) and 6 months (54.52 ± 11.78). There was also significant improvement (p < 0.05) in OKS score from pre-procedure (31.1 ± 3.47) to post-procedure at 1 month (39.06 ± 3.37) and 6 months (34.10 ± 3.75). No adverse effects were reported in patients during the study period.

Conclusion

This small retrospective study suggests that a single administration of intraarticular PRP may be safe and effective for pain relief and functional improvement for up to 6 months in patients of early-stage osteoarthritis.

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

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

Combination of percutaneous endoscopic lumbar discectomy and platelet-rich plasma hydrogel injection for the treatment of lumbar disc herniation

OBJECTIVE

To determine the safety and efficacy of percutaneous endoscopic lumbar discectomy (PELD) combined with platelet-rich plasma (PRP) hydrogel injection in patients with lumbar disc herniation (LDH).

METHODS

A total of 98 consecutive patients with LDH who underwent either PELD combined with PRP hydrogel injection or PELD alone were reviewed. This retrospective study was performed between January 2019 and January 2021. Clinical outcomes were compared in the visual analog scale (VAS) for low back pain and leg pain, Oswestry disability index (ODI), Japanese Orthopaedic Association (JOA) scores, and Macnab criteria. Intervertebral disc height on MRI was measured, and the Pfirrmann grade classification was used pre-operatively and post-operatively.

RESULTS

No severe adverse events were reported during an 18-month follow-up period. VAS scores for back pain were decreased at 1 month, 3 months, and 18 months in the treatment group than that in the control group. JOA score and ODI in the treatment group at 3-month and 18-month follow-up was lower than that in the control group (P < 0.05). The excellent and good rate of the Macnab criteria was 92.0% (46/50) in the treatment group and 89.6% (43/48) in the control group (P > 0.05). The comparison of Pfirrmann grading and disc height at 18-month follow-up showed significant difference in two groups (P < 0.05). The recurrence of LDH in the treatment group was lower than that in the control group (P < 0.05).

CONCLUSIONS

We suggest that PELD combined with PRP hydrogel injection to treat patients with LDH is a safe and promising method. PRP injection was beneficial for disc remodelling after PELD.

Do age, gender, BMI and disease duration influence the clinical outcomes in patients of knee osteoarthritis treated with serial injections of autologous platelet rich plasma?

Purpose

To study whether age, gender, body mass index(BMI) and disease duration influence the clinical outcomes in kellgren-Lawrence(K-L) grade II,III knee osteoarthritis(KOA) patients treated with serial injections of platelet rich plasma(PRP).

Patients and methods

65 patients were given three monthly intra-articular injections of PRP in this prospective interventional study. The patients were divided into subgroups depending on the factor studied: by age(in years) into young <45(n = 7), middle age 45-60(n = 35), and elderly >60(n = 23): by BMI(in kg/m2) into; normal <25(n = 25), overweight 25-30(n = 27) and obese >30(n = 13) and disease duration; less(n = 32) or more than 1 year(n = 33) symptom duration. Visual analogue scale (VAS) and Western Ontario and McMaster Universities Arthritis Index (WOMAC) were used as outcome measures and assessed before each injection and then at 6 and 9 months post injection. Groups were homogenous with respect to baseline characteristics.

Results

Mean VAS and WOMAC scores showed a statistically significant improvement (P < 0.0001) across all groups and subgroups (age,gender,BMI,disease duration) at follow up. On intra-subgroup comparison, we found no significant differences(P > 0.05) among age, BMI or gender subgroups, however the scores were significantly better in patients with disease duration of less than 1 year than those with more than 1 year duration at both 6 and 9 months[P < 0.001(RC = 9.630,95% CI = 4.037-15.222,P = 0.001)].

Conclusion

PRP injections if given serially can improve the short term subjective scores of VAS and WOMAC scores in patients with K-L grade II and III KOA irrespective of age, gender, BMI or disease duration, however, clinical benefits can be maximized if given early in the disease course.

Orthobiologics: a review

PURPOSE

The use of biologic materials in orthopaedics (orthobiologics) has gained significant attention over the past years. To enhance the body of the related literature, this review article is aimed at summarizing these novel biologic therapies in orthopaedics and at discussing their multiple clinical implementations and outcomes.

METHODS

This review of the literature presents the methods, clinical applications, impact, cost-effectiveness, and outcomes, as well as the current indications and future perspectives of orthobiologics, namely, platelet-rich plasma, mesenchymal stem cells, bone marrow aspirate concentrate, growth factors, and tissue engineering.

RESULTS

Currently available studies have used variable methods of research including biologic materials as well as patient populations and outcome measurements, therefore making comparison of studies difficult. Key features for the study and use of orthobiologics include minimal invasiveness, great healing potential, and reasonable cost as a nonoperative treatment option. Their clinical applications have been described for common orthopaedic pathologies such as osteoarthritis, articular cartilage defects, bone defects and fracture nonunions, ligament injuries, and tendinopathies.

CONCLUSIONS

Orthobiologics-based therapies have shown noticeable clinical results at the short- and mid-term. It is crucial that these therapies remain effective and stable in the long term. The optimal design for a successful scaffold remains to be further determined.

Is 3D Printing Promising for Osteochondral Tissue Regeneration?

Osteochondral tissue regeneration is quite difficult to achieve due to the complexity of its organization. In the design of these complex multilayer structures, a fabrication method, 3D printing, started to be employed, especially by using extrusion, stereolithography and inkjet printing approaches. In this paper, the designs are discussed including biphasic, triphasic, and gradient structures which aim to mimic the cartilage and the calcified cartilage and the whole osteochondral tissue closely. In the first section of the review paper, 3D printing of hydrogels including gelatin methacryloyl (GelMa), alginate, and polyethylene glycol diacrylate (PEGDA) are discussed. However, their physical and biological properties need to be augmented, and this generally is achieved by blending the hydrogel with other, more durable, less hydrophilic, polymers. These scaffolds are very suitable to carry growth factors, such as TGF-β1, to further stimulate chondrogenesis. The bone layer is mimicked by printing calcium phosphates (CaPs) or bioactive glasses together with the hydrogels or as a component of another polymer layer. The current research findings indicate that polyester (i.e. polycaprolactone (PCL), polylactic acid (PLA) and poly(lactide-co-glycolide) (PLGA)) reinforced hydrogels may more successfully mimic the complex structure of osteochondral tissue. Moreover, more recent printing methods such as melt electrowriting (MEW), are being used to integrate polyester fibers to enhance the mechanical properties of hydrogels. Additionally, polyester scaffolds that are 3D printed without hydrogels are discussed after the hydrogel-based scaffolds. In this review paper, the relevant studies are analyzed and discussed, and future work is recommended with support of tables of designed scaffolds. The outcome of the survey of the field is that 3D printing has significant potential to contribute to osteochondral tissue repair.

The effect of PRP and hyperosmolarity simultaneous use on expression profile alteration of miRNAs associated with cartilage differentiation in human adipose tissue-derived mesenchymal stem cells

BACKGROUND

Mesenchymal stem cells (MSC) are a type of multipotent stem cell whose differentiation into cartilage cells has been considered in recent years. Platelet-rich plasma (PRP) may impair cartilage differentiation due to its richness in growth factors and hyperosmolarity due to its proximity to the required cartilage environment.

OBJECTIVES

The main purpose of this study was to treat human adipose tissue-derived MSCs concurrently with PRP and hyperosmolarity to investigate the expression profile of micro-RNA (miRNA) involved in the cartilage process differentiation. We examined the effect of PRP and the increase in osmolarity on the expression of miR-27, miR-101, miR-140, miR-145, miR-146, and miR-199.

METHODS

Mesenchymal stem cells were extracted from human adipose tissue and differentiated into chondrocytes and the effect of baseline cultures (diff), PRP (prp), hyperosmolarity (os), base plus hyperosmolarity (diff + os), PRP plus hyperosmolarity (prp + os) next to the control group were studied in cartilage differentiation using specific stains such as Alcian blue, hematoxylin and eosin, and collagen type 2 and 10 immunohistochemistry. In addition, the expression of miR-27, miR-140, miR-199, miR-146, miR-101, and miR-145 was evaluated using real-time PCR.

CONCLUSION

Human adipose tissue-derived MSCs with the ability to differentiate into adipocytes and osteocytes showed the properties of chondrocytes in all differentiation groups. Alkaline phosphatase (ALP) enzyme activity and calcium deposition were lower in the diff + os group than in other groups. Therefore, the diff + os group may be a more suitable environment for cartilage differentiation. Furthermore, 5% PRP concentration and hyperosmolarity showed a positive effect on miR-140, miR-199, miR-27, and, miR-146 and a negative effect on miR-101 and miR-145 on cartilage differentiation.

Comparison of intra-articular lumbar facet joint injection of platelet-rich plasma and steroid in the treatment of chronic low back pain: A prospective study

Study design: Prospective randomized clinical study. Purpose: To compare the effectiveness and safety of intra-articular platelet-rich plasma (PCP) and steroid along with radiofrequency ablation (RFA) in the treatment of chronic low back pain (LBP) due to facet joint arthropathy. Overview of literature: Facet joint pathology is an important cause of LBP—15–30% of all LBP cases. Lumbar intra-articular PRP is a relatively new method in the treatment of LBP. PRP stimulates the cells involved in regeneration. Hence, it seems a suitable option for the treatment of lumbar facet joint syndrome. Methods: We evaluated the efficacy and safety of facet joint injections in LBP secondary to facet joint arthropathy. Chronic LBP for ≥3 months (visual analogue scale (VAS) > 4), failed conservative treatment, no neurological deficit, unilateral facet joint pain, focal tenderness with hyperextension pain, and relief by diagnostic medial branch block were included. Patients were randomly allocated to Group S: Steroid (Triamcinolone) + RFA or Group P: PRP + RFA or Group R: 0.9% saline + RFA as control. Demographic, clinico-radiological, and outcome parameters were recorded till 6 months. Data were analyzed using SPSS and p < 0.05 was considered significant. Results: We studied 45 patients (n = 15 in each group) in the final analysis. Mean age was 45.7 ± 13.6 years and 60% were females in all groups. VAS decreased to 1.6 ± 0.8 (Group S) and 3.2 ± 0.8 (Group P) on day 1 ( p < 0.05). At 3 and 6 months, VAS reduced more in Group P (0.47 ± 0.5; 0.07 ± 0.2) versus Group S (2.53 ± 0.5; 3.07 ± 0.2) ( p < 0.001). Mean Oswestry Disability Index (ODI) score at baseline was 72.8 ± 7.6 (all groups). At 1 month, Group S (17.2 ± 3.2) showed better improvement than Group P (23.2 ± 3.1) ( p < 0.05). At 6 months, Group P (8.9 ± 1.2) had more decrease in ODI than Group S (29.0 ± 2.1) ( p < 0.001). NSAIDs usage and Patient Satisfaction Score (PSS) were significantly better at 6 months in Group P than Group S ( p < 0.01; p < 0.05, respectively). Conclusion: Both PRP and corticosteroid injections were determined to be effective and safe for the treatment of lumbar facet joint syndrome after 6 months of follow-up. However, autologous PRP may be a superior treatment option for longer efficacy.

Patients With Knee Osteoarthritis Who Receive Platelet-Rich Plasma or Bone-Marrow Aspirate Concentrate Injections Have Better Outcomes Than Patients Who Receive Hyaluronic Acid: Systematic Review and Meta-analysis

PURPOSE

To systematically review the literature in order to compare the efficacy and safety of platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and hyaluronic acid (HA) injections for the treatment of knee osteoarthritis (OA).

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I studies that compared the clinical efficacy of at least 2 of the following 3 injection therapies: PRP, BMAC, and HA for knee OA. The search phrase used was knee AND osteoarthritis AND randomized AND ("platelet rich plasma" OR "bone marrow aspirate" OR "hyaluronic acid"). Patients were primarily assessed based on patient-reported outcome scores (PROs) including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) score.

RESULTS

Twenty-seven studies (all Level I) met inclusion criteria, including 1,042 patients undergoing intra-articular injection(s) with PRP (mean age 57.7 years, mean follow-up 13.5 months), 226 patients with BMAC (mean age 57.0 years, mean follow-up 17.5 months), and 1,128 patients with HA (mean age 59.0 years, mean follow-up 14.4 months). Non-network meta-analyses demonstrated significantly better post-injection WOMAC (p < 0.001), VAS (p < 0.01), and Subjective IKDC scores (p < 0.001) in PRP patients when compared to HA patients. Similarly, network meta-analyses demonstrated significantly better post-injection WOMAC (p < 0.001), VAS (p = 0.03), and Subjective IKDC (p < 0.001) scores in BMAC patients when compared to HA patients. There were no significant differences in post-injection outcome scores when comparing PRP to BMAC.

CONCLUSION

Patients undergoing treatment for knee OA with PRP or BMAC can be expected to experience improved clinical outcomes when compared to HA patients.

LEVEL OF EVIDENCE

I, Meta-Analysis of Level I studies.

The role of Platelet-Rich Plasma (PRP) intraarticular injections in restoring articular cartilage of osteoarthritic knees. A systematic review and meta-analysis

Objective

To assess the effect of PRP on knee articular cartilage content (thickness/volume) and examine the correlation between cartilage changes and clinical outcomes in patients with knee OA.

Method

A systematic literature search was performed using the Cochrane methodology in four online databases. Studies were included if they reported on cartilage content with cross-sectional imaging pre- and post-injection. A random-effects model meta-analysis was performed. Correlation with clinical outcomes was evaluated.

Results

14 studies (n ​= ​1099 patients) from 1452 records met the inclusion criteria: seven RCTs (n ​= ​688), one prospective (n ​= ​50), one retrospective (n ​= ​68), and four case-series (n ​= ​224). The PRP preparation process and treatment protocol varied widely (follow-up 6-12 months). In meta-analysis, PRP treatment was not associated with a significant increase in cartilage thickness (4 studies, n ​= ​187, standardized mean difference: Hedges g: 0.079; 95%CI: 0.358 - 0.516; p ​= ​0.723). Meta-analysis of 3 RCTs (n ​= ​112) showed no significant difference in the change of overall knee cartilage content with PRP injections compared with no PRP (Hedges' g: 0.217; 95%CI: 0.177 - 0.611; P ​= ​0.281).

Conclusion

The current literature does not support the PRP as chondrogenic in treatment of knee OA. However, there is substantial heterogeneity in the evaluated studies which limits the robustness of any conclusion. An adequately powered RCT, with a standardized PRP regime and standardized high-resolution MRI is needed to definitely define any effect of PRP on knee cartilage content and its relation to clinical outcomes. Until such high-quality evidence becomes available, we recommend that PRP is not administered with the intention of promoting chondrogenesis.

Multiple platelet-rich plasma injections are superior to single PRP injections or saline in osteoarthritis of the knee: the 2-year results of a randomized, double-blind, placebo-controlled clinical trial

INTRODUCTION

The primary purposes of this study were to prove the efficacy of PRP injection therapy on knee pain and functions by comparing patients with mild to moderate OA with a placebo control group, and also to understand the effectiveness of multiple doses compared to a single dose. It was hypothesized that PRP would lead to more favorable results than the placebo at 1, 3, 6, 12 and 24 months after treatment.

MATERIALS AND METHODS

237 patients diagnosed with OA were randomly separated into 4 groups, who were administered the following: single dose of PRP (n: 62), single dose of sodium saline (NS) (n: 59), three doses of PRP (n: 63), and three doses of NS (n: 53). Clinical evaluations were made pre-treatment and at 1, 3, 6, 12 and 24 months post-treatment, using the Knee Injury and Osteoarthritis Result Score (KOOS), Kujala Patellofemoral Score, knee joint range of motion (ROM), measurements of knee circumference (KC), and mechanical axis angle (MAA) and a Visual Analog Scale (VAS) for the evaluation of pain.

RESULTS

The better score values in the groups were recorded at 3 and 6 months. Patients treated with PRP maintained better scores at 3, 6 and 12 months compared to the NS groups (p < 0.05). Multiple doses of PRP were seen to be more effective than single-dose PRP at 6 and 12 months (p < 0.05). At the end of 24 months, there was no significant score difference across all the groups. The most positive change in scores was found in stage 2 OA, and the most positive change in ROM was in stage 3 OA patients. In the PRP groups, KC decreased more at 1 and 6 months (p < 0.05). Compared to other age groups, patients aged 51-65 years scored better at 6 months (p < 0.05). A negative correlation was determined with MAA scores (r = - 0.508, p < 0.001).

CONCLUSION

In comparison to the placebo (NS), leukocyte-rich PRP treatment was determined to be effective in the treatment of OA. Multiple doses of PRP increase the treatment efficacy and duration. Of all the patients treated with PRP, the best results were obtained by patients aged 51-65 years, with lower MAA, and by K/L stage 2 OA patients.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

REGISTRATION

NCT04454164 (ClinicalTrials.gov identifier).

The retrospective analysis of platelet-rich plasma and corticosteroid injection under epiduroscopic guidance for radiculopathy in operated or unoperated patients for lumbar disc herniation

Objectives: Epiduroscopy is a treatment method that can be applied to operated or non-operated patients with lumbar disc pathology. The aim of our study was to investigate and compare the efficacy of corticosteroid and platelet-rich plasma (PRP) therapy that we have injected in epidural and foraminal spaces under the guidance of epiduroscopy in the operated or unoperated patients with radicular pain.

Patients and methods: The retrospective study was conducted with 62 patients (40 females, 22 males; mean age: 48±12.3 years; range, 20 to 75 years) between January 2014 and September 2020. Of the patients, 32 were unoperated, whereas 30 were operated. All the patients had radicular pain. All the patients were evaluated by the Visual Analog Scale (VAS) and the Oswestry Disability Index (ODI) at the start, on the 10th day, and at one and six months after the procedure by polyclinic control and by a phone call for their last follow-up.

Results: The VAS and ODI scores of patients treated with corticosteroid and PRP were decreased on the 10th day, at one and six months and the last follow-up, and this decrease was statistically significant.

Conclusion: Both PRP and corticosteroid injections were effective in pain scores during short-term and long-term follow-ups owing to the contribution of epiduroscopic intervention by allowing local administration of PRP or corticosteroids and analgesic agents as well as its mechanical adhesiolysis effect.

Platelet-Rich Plasma Versus Hyaluronic Acid for Hip Osteoarthritis Yields Similarly Beneficial Short-Term Clinical Outcomes: A Systematic Review and Meta-analysis of Level I and II Randomized Controlled Trials

PURPOSE

To systematically review the literature to compare the efficacy of platelet-rich plasma (PRP) and hyaluronic acid (HA) injections for the treatment of hip osteoarthritis (OA).

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify randomized controlled trials that compared the clinical efficacy of PRP and HA injections for hip OA. The search phrase used was hip, osteoarthritis, platelet-rich plasma, hyaluronic acid, randomized. Patients were assessed based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the Visual Analog Scale (VAS) for pain, and the Harris Hip Score (HHS). Subanalyses were performed for any outcome score in which ≥3 studies reported results.

RESULTS

Six studies (5 level I, 1 level II) met inclusion criteria, including 211 patients undergoing intra-articular injection with PRP (mean age 60.0 years, mean follow-up 12.2 months) and 197 patients with HA (mean age 62.3 years, mean follow-up 11.9 months). No significant differences were found in the weighted improvement of any outcome score (WOMAC, VAS, or HHS) from preinjection to postinjection between groups. When excluding a study with the highest risk of bias to eliminate heterogeneity, pooled subanalysis demonstrated no significant differences in WOMAC subscores between PRP and HA groups. Similarly, in a pooled subanalysis that isolated patients treated with leukocyte-poor PRP, no significant differences in WOMAC subscores were found between PRP and HA groups.

CONCLUSION

Patients undergoing treatment for hip OA with either PRP or HA injections can expect to experience similarly beneficial short-term clinical outcomes.

LEVEL OF EVIDENCE

II, systematic review of level I and II studies.

A single intraarticular platelet-rich plasma improves pain and function for patients with early knee osteoarthritis: Analyses by radiographic severity and age

BACKGROUND

Most studies use platelet-rich plasma (PRP) requiring multiple intraarticular injections for knee osteoarthritis (OA).

OBJECTIVE

To investigate the efficacy of a single intraarticular PRP injection for patients with early knee OA and consider subgroup analyses of radiographic severity and age, respectively.

METHODS

Forty-one patients with knee OA (Kellgren-Lawrence grade 1-2) received a single PRP injection into the target knee and were assessed at baseline and 1, 3, and 6 months postinjection. The primary outcome was the mean change from baseline in the visual analog scale (VAS) pain (0-100 mm) at 6 months postinjection. Secondary outcomes included the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Lequesne index, single leg stance test (SLS), use of rescue analgesics and patients' satisfaction.

RESULTS

Thirty-eight patients completed the study. The mean pain VAS decreased significantly from 45.6 ± 13.0 mm at baseline to 16.9 ± 13.4 mm, 14.0 ± 13.1 mm and 15.5 ± 14.0 mm at 1, 3 and 6-month follow-ups (p< 0.001 for all). Significant improvements in WOMAC, Lequesne index, SLS and consumption of analgesics from baseline (p< 0.001 for all) were noted at each follow-up. Patients' satisfaction was high. No serious adverse events occurred. Subgroup analyses revealed that patients with grade 1 OA showed significantly greater VAS pain reduction at 3 months (p= 0.006) and 6 months (p= 0.005) than patients with grade 2 OA. The older-age group (age > 60) showed significantly greater improvements in VAS pain, WOMAC function subscale scores and total scores at 6-month postinjection, compared with the younger age-group (age ≤ 60). The younger-age group reported better satisfaction at 1 and 3-month postinjection.

CONCLUSIONS

One injection of PRP improved pain and function for 6 months for patients with early knee OA. This study supports putting the one-injection regimen into clinical practice. Further research is needed for more definite conclusions.

Hypertonic Dextrose Prolotherapy, an alternative to intra-articular injections with Hyaluronic Acid in the treatment of knee osteoarthritis: systematic review and meta-analysis

ABSTRACT

Intra-articular injections with hyaluronic acid are recommended in the treatment of knee osteoarthritis (KOA); however, hypertonic dextrose prolotherapy (HDP) has been reported as effective and safe. The aim was to evaluate the effectiveness of HDP for pain reduction and improvement of function in individuals with KOA in comparison with hyaluronic acid by meta - analysis. The search was performed in electronic databases. Six studies were included (395 participants). No statistically significant differences were found between prolotherapy and hyaluronic acid in pain control in the short term, however, in the sub-analysis where included only the studies that used intra-articular injection within the prolotherapy scheme, an effect was found in favor of the prolotherapy groups (d = -1.33, 95% CI -2.50 to -0.16, p (z) 0.03). Also, an effect was found in favor of the prolotherapy group in the improvement in function (d = -1.05, 95% CI -2.03 to -0.08, p (z) 0.03). No major adverse reactions or side effects were reported in any of the studies. HDP appears to be an effective intervention to decrease pain and improve function in KOA, with efficacy similar to intra-articular injections with hyaluronic acid in the short-term follow-up. Nonetheless, better-quality clinical trials are necessary.

Bone Marrow Aspirate Concentrate versus Platelet Rich Plasma or Hyaluronic Acid for the Treatment of Knee Osteoarthritis

Background: In the last decade, regenerative therapies have become one of the leading disease modifying options for treatment of knee osteoarthritis (OA). Still, there is a lack of trials with a direct comparison of different biological treatments. Our aim was to directly compare clinical outcomes of knee injections of Bone Marrow Aspirate Concentrate (BMAC), Platelet-rich Plasma (PRP), or Hyaluronic acid (HA) in the OA treatment. Methods: Patients with knee pain and osteoarthritis KL grade II to IV were randomized to receive a BMAC, PRP, and HA injection in the knee. VAS, WOMAC, KOOS, and IKDC scores were used to establish baseline values at 1, 3, 6, 9, and 12 months. All side effects were reported. Results: A total of 175 patients with a knee osteoarthritis KL grade II-IV were randomized; 111 were treated with BMAC injection, 30 with HA injection, and 34 patients with PRP injection. There were no differences between these groups when considering KL grade, BMI, age, or gender. There were no serious side effects. The mean VAS scores after 3, 7, 14, and 21 days showed significant differences between groups with a drop of VAS in all groups but with a difference in the BMAC group in comparison to other groups (p < 0.001). There were high statistically significant differences between baseline scores and those after 12 months (p < 0.001) in WOMAC, KOOS, KOOS pain, and IKDC scores, and in addition, there were differences between these scores in the BMAC group in comparison with other groups, except for the PRP group in WOMAC and the partial IKDC score. There were no differences between the HA and PRP groups, although PRP showed a higher level of clinical improvement. Conclusions: Bone marrow aspirate concentrate, Leukocyte rich Platelet Rich Plasma, and Hyaluronic acid injections are safe therapeutic options for knee OA and provide positive clinical outcomes after 12 months in comparison with findings preceding the intervention. BMAC could be better in terms of clinical improvements in the treatment of knee OA than PRP and HA up to 12 months. PRP provides better outcomes than HA during the observation period, but these results are not statistically significant. More randomized controlled trials and high quality comparative studies are needed for direct correlative conclusions.

Cell penetration and chondrogenic differentiation of human adipose derived stem cells on 3D scaffold

The ability of cells to penetrate the scaffold and differentiate into chondrocyte is important in cartilage engineering. The aim of this research was to evaluate the use of silk fibroin 3D scaffold in facilitating the growth of stem cell and to study the role of L-ascorbic acid and platelet rich plasma (PRP) in proliferation and differentiation genes. Cell penetration and type II collagen content in the silk fibroin scaffold was analyzed by confocal microscopy. Relative expressions of CDH2, CCND1, CTNNB1 and COL2A1 were analyzed by reverse transcription-quantitative PCR (RT-qPCR). The silk fibroin 3D scaffold could facilitate cell penetration. L-ascorbic acid and PRP increased the expression of CDH2 and COL2A1 on the 21st day of treatment while PRP inhibited CTNNB1 and CCND1.

Orthobiologics and hyaluronic acid usage in the Netherlands: an electronic survey of 265 orthopaedic surgeons and sports physicians

Purpose

“Biologic therapies” in the field of orthopaedic surgery and sports medicine, so called orthobiologics, have been gaining significant interest from physicians and patients, with increasing usage over the recent years. The aim of this study is to (1) evaluate the usage of orthobiologics in the Netherlands, (2) to clarify the reasons for the use or non-use of orthobiologics, and (3) the most addressed disease for use of orthobiologics.

Methods

The authors created a 19-quenstion online survey comprised of both closed-ended and open-ended response questions in order to examine the use of and the indication for orthobiologics. The survey was sent to all the members of the Dutch Orthopaedic Association and Netherlands Association of Sports Medicine of which 15% responded.

Results

The majority of the 265 respondents (65%) did not treat patients with or refer patients for treatment with orthobiologics. The most important reasons for not using orthobiologics were the lack of scientific evidence, the lack of good experience, and the lack of insurance coverage. Of the physicians that used orthobiologics, the most used hyaluronic acid (76%) and platelet-rich plasma (27%). Orthobiologics were most used for knee osteoarthritis and medial or lateral epicondylitis.

Conclusion

Although some orthobiologic treatments might be effective and the research interest is growing, our study shows that the majority of orthopaedic and sport physician clinicians in the Netherlands still does not make use of orthobiologics as a treatment option, but almost a third of them is contemplating to start using orthobiologics.

Level of evidence

III.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40634-021-00380-9.

Efficacy and Safety of a Single Intra-articular Injection of Platelet-rich Plasma on Pain and Physical Function in Patients With Ankle Osteoarthritis-A Prospective Study

Ankle osteoarthritis (OA) can cause disabling symptoms, and some patients prefer to be treated with minimally invasive procedures. The aim was to evaluate the efficacy and safety of a single intraarticular injection of platelet-rich plasma (PRP) for patients with ankle OA. In a prospective study done in a university-affiliated tertiary care medical center, 44 patients with symptomatic ankle OA for at least 6 months were recruited. Patients received a single injection of PRP (3 mL) into symptomatic ankles. The primary outcome was the change from baseline in the visual analog scale (VAS) pain (0-10 cm) at 6 months. Secondary outcomes included the Ankle Osteoarthritis Scale (AOS) score, American Orthopedic Foot and Ankle Society (AOFAS) hindfoot-ankle score, single-leg stance test (SLS), rescue analgesics consumption and patient satisfaction. Thirty-nine participants (88.64%) completed the study. Significantly improvement in the VAS and AOS was noted at 1-, 3-, and 6-month follow-ups (p < .001). The mean VAS pain decreased significantly from 4.1 ± 1.7 at baseline to 2.2 ± 1.9, 1.7 ± 1.5, and 1.8 ± 1.6 at 1, 3, and 6 months (p < .001). The mean total AOS score reduced by 1.5, 2.2, and 2.1 from baseline respectively postinjection (p < .001). The mean AOFAS hindfoot-ankle score improved from 80.3 points at baseline to 87.2, 91.6, and 89.7 points at 1, 3, and 6 months (p < .001). SLS tests improved significantly (p < .001) at each follow-up. Acetaminophen consumption dropped significantly (p < .001) and no serious adverse events occurred. The study showed promise for a single intraarticular injection of PRP in the treatment of ankle OA.

Intra-Articular Injections of Platelet-Rich Plasma, Adipose Mesenchymal Stem Cells, and Bone Marrow Mesenchymal Stem Cells Associated With Better Outcomes Than Hyaluronic Acid and Saline in Knee Osteoarthritis: A Systematic Review and Network Meta-analysis

PURPOSE

To perform a network meta-analysis to evaluate clinical efficacy and treatment-related adverse events (AEs) of intra-articular hyaluronic acid (HA), leukocyte-poor platelet-rich plasma (LP-PRP), leukocyte-rich platelet-rich plasma (LR-PRP), bone marrow mesenchymal stem cells (BM-MSCs), adipose mesenchymal stem cells (AD-MSCs), and saline (placebo) during 6 and 12 months of follow-up.

METHODS

Six databases were searched for randomized controlled trials. Outcome assessment included the visual analog scale (VAS) score, Western Ontario and McMaster Universities Osteoarthritis (WOMAC) pain subscore, WOMAC score, International Knee Documentation Committee (IKDC) subjective score, and treatment-related AEs. Main inclusion criteria were at least one of the aforementioned outcome measurements, a minimum follow-up period of 5 months, and >80% patient follow-up. Treatments combined with the use of other operations or drugs were excluded.

RESULTS

Forty-three studies meeting the eligibility criteria were included. At 6 months, VAS scores and WOMAC pain subscores showed that AD-MSCs were the best treatment option (surface under the cumulative ranking curve [SUCRA] = 96.7%, SUCRA = 85.3%, respectively). According to WOMAC scores and subjective IKDC scores, LP-PRP was the most effective treatment (SUCRA = 86.0%, SUCRA = 80.5%, respectively). At 12 months, only AD-MSCs were associated with improved VAS scores compared with the placebo (weighted mean difference [WMD] = -20.93, 95% credibility interval [CrI], -41.71 to -0.78). Both LP-PRP and AD-MSCs were more beneficial than the placebo for improving WOMAC pain subscores (WMD = -30.08; 95% CrI, -53.59 to -6.25; WMD = -34.85; 95% CrI, -68.03 to -4.86, respectively). For WOMAC scores, LP-PRP and LR-PRP were significantly associated with improved WOMAC scores compared with the placebo after sensitivity analysis was performed (WMD = -35.26; 95% CrI, -64.99 to -6.01; WMD = -38.69; 95% CrI, -76.21 to -2.76). LP-PRP exhibited relatively better efficacy in improving subjective IKDC scores than the placebo (WMD = 13.67; 95% CrI, 4.05-23.39). Regarding safety, all treatments except for LP-PRP (relative risk = 1.83; 95% CrI, 0.89-4.64) increased treatment-related AEs compared with the placebo.

CONCLUSIONS

Based on the results of current research findings, during 6 months of follow-up, AD-MSCs relieved pain the best; LP-PRP was most effective for functional improvement. During the 12-month follow-up, both AD-MSCs and LP-PRP showed potential clinical pain relief effects; functional improvement was achieved with LP-PRP. Unfortunately, AD-MSC/LP-PRP functional comparisons were only based on WOMAC scores due to missing IKDC scores. BM-MSCs seem to have potentially beneficial effects, but the wide credibility interval makes it impossible to draw a well-supported conclusion. HA viscosupplementation clinical efficacy was lower than that of biological agents during follow-up, which may be related to the properties of the drugs. Considering the evaluation of treatment-related AEs, LP-PRP is the most advisable choice; although the AEs of these treatments are not serious, they may affect treatment compliance and satisfaction.

LEVEL OF EVIDENCE

Level II, meta-analysis of Level I and II studies.

Intra-articular platelet-rich plasma injections versus intra-articular corticosteroid injections for symptomatic management of knee osteoarthritis: systematic review and meta-analysis

Background

Intra-articular (IA) corticosteroid (CS) injections are the mainstay of treatment for symptomatic management in knee osteoarthritis (OA), particularly in the UK. IA platelet-rich plasma (PRP) injections are a promising alternative, but no systematic reviews to date have compared them to the current standard of care, IA CS injections. We aim to investigate the effect of IA PRP injections versus IA corticosteroid injections for the symptomatic management of knee OA.

Methods

All published trials comparing IA PRP and CS injections for knee OA were included. MEDLINE, EMBASE, Scopus and Web of Science were searched through June 2020. Risk of bias was assessed using the Cochrane Risk of Bias tool. A random effects model was used to calculate standardized mean difference with 95% confidence interval in WOMAC/VAS score (or subscores), comparing IA PRP to CS injections across studies.

Results

Included were eight studies and 648 patients, 443 (68%) were female, mean age 59 years, with a mean BMI of 28.4. Overall, the studies were considered at low risk of bias. Compared with CS injections, PRP was significantly better in reducing OA symptoms (pain, stiffness, functionality) at 3, 6 and 9 months post-intervention (P < 0.01). The greatest effect was observed at 6 and 9 months (− 0.78 (− 1.34 to − 0.23) standard mean deviations (SMD) and − 1.63 (− 2.14 to − 1.12) SMD respectively). At 6 months, this equates to an additional reduction of 9.51 in WOMAC or 0.97 on the VAS pain scales. At 6 months PRP allowed greater return to sporting activities than CS, measured by the KOOS subscale for sporting activity, of magnitude 9.7 (− 0.45 to 19.85) (P = 0.06). Triple injections of PRP, generally separated by a week, were superior to single injections over 12 months follow-up (P < 0.01).

Conclusions

IA-PRP injections produce superior outcomes when compared with CS injections for symptomatic management of knee OA, including improved pain management, less joint stiffness and better participation in exercise/sporting activity at 12 months follow-up. Giving three IA-PRP, with injections separated by a week, appears more effective than 1 IA-PRP injection.

Prospero trial registration number

CRD42020181928.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12891-021-04308-3.

Review: Mesenchymal Stem Cell Therapy in Canine Osteoarthritis Research: "Experientia Docet" (Experience Will Teach Us)

Osteoarthritis (OA) is currently an incurable and progressive condition in dogs causing chronic joint pain and possibly increasing disability. Due to the poor healing capacity of cartilage lesions that occur with OA, development of effective therapeutics is difficult. For this reason, current OA therapy is mostly limited to the management of pain and inflammation, but not directed ad disease modification. In the search for a safe and effective OA treatment, mesenchymal stem cells (MSCs) have been of great interest since these cells might be able to restore cartilage defects. The designs of OA studies on MSC usage, however, are not always consistent and complete, which limits a clear evaluation of MSC efficacy. The general study results show a tendency to improve lameness, joint pain and range of motion in dogs suffering from naturally-occurring OA. Assessment of the cartilage surface demonstrated the ability of MSCs to promote cartilage-like tissue formation in artificially created cartilage defects. Immunomodulatory capacities of MSCs also seem to play an important role in reducing pain and inflammation in dogs. It should be mentioned, however, that in the current studies in literature there are specific design limitations and further research is warranted to confirm these findings.

Glenohumeral Osteoarthritis: The Role for Orthobiologic Therapies: Platelet-Rich Plasma and Cell Therapies

The glenohumeral (GH) joint ranks third on the list of the large joints that are most commonly affected by osteoarthritis, after the knee and the hip. General nonsurgical modalities, including changes in daily activities, physical therapy, pharmacotherapy, and corticosteroid injections, constitute the mainstay of treatment. Most of these options, however, have shown moderate and short-term effectiveness. Arthroplasty techniques have proven to be successful for elderly patients. Nevertheless, replacement options are not optimal for younger patients because their functional demands are higher and prostheses have a finite life span. This has led to the search for new nonoperative treatment options to target this subgroup of patients. It has been suggested that orthobiologic therapies, including platelet-rich plasma (PRP) and cell therapies, present great promise and opportunity for the treatment of GH osteoarthritis. Despite the promising results that have been shown by cell therapies and PRP for treating degenerative joint conditions, additional studies are needed to provide more definitive conclusions.

Osteoarthritis of the shoulder in under-50 year-olds: A multicenter retrospective study of 273 shoulders by the French Society for Shoulder and Elbow (SOFEC)

INTRODUCTION

Osteoarthritis (OA) of the shoulder in under-50 year-olds is rare, and treatment is delicate. Shoulder replacement incurs frequent long-term risk of progression and a high revision rate, making it unsuited to young active patients. The aim of the present study was to determine the epidemiology of shoulder OA in under-50 year-olds and to assess the clinical results of the various treatment options.

HYPOTHESIS

The main study hypothesis was that well-conducted non-operative treatment can allow shoulder replacement to be postponed. The secondary hypothesis was that anatomic total shoulder arthroplasty (TSA) is the treatment of choice when other options fail.

MATERIALS AND METHODS

A multicenter retrospective study included primary (POA) and post-instability osteoarthritis (PIOA) in patients aged≤50years at symptom onset. Exclusion criteria comprised post-traumatic OA, rheumatoid arthritis and necrosis. Two hundred and sixty-six patients for 273 shoulders were included from 13 shoulder surgery centers: 2 types of non-operative treatment (28 by platelet-rich plasma [PRP] and 88 by viscosupplementation), 73 arthroscopies, and 150 implantations (62 humeral hemiarthroplasties [HA], comprising 10 hemi-metal, 24 hemi-pyrocarbon and 28 hemi-resurfacing; 77 anatomic total prostheses, and 11 reverse prostheses). Minimum follow-up was 12 months for non-operative treatment and 24 months for arthroplasty (some patients having both). Endpoints comprised Constant score, Subjective Shoulder Value (SSV) and number of complications/revision procedures.

RESULTS

Mean age at treatment was 43 years (range, 23-65 years), with 75% male predominance. Symptom onset was earlier in PIOA than in POA: 36 vs. 39 years (range, 20-50 years). PRP and viscosupplementation postponed implantation by a mean 3.5 years in 86% of cases, as did arthroscopy in 56%. ER1 restriction was the most negative factor. At 74 months' follow-up for HA and 95 months for TSA, mean Constant score was significantly lower for HA (56 vs. 67; p=0.004), with higher rates of complications (31% vs. 11%) and implant exchange (13% vs. 9%).

DISCUSSION/CONCLUSION

PRP, viscosupplementation and arthroscopy allow implantation to be postponed until the shoulder becomes stiff and painful. In case of failure, TSA is the most effective solution in the medium-term.

LEVEL OF EVIDENCE

IV a; therapeutic study - investigating the results of treatment.

Comparative Analysis of Mesenchymal Stem Cell Cultivation in Fetal Calf Serum, Human Serum, and Platelet Lysate in 2D and 3D Systems

In vitro two-dimensional (2D) and three-dimensional (3D) cultivation of mammalian cells requires supplementation with serum. Mesenchymal stem cells (MSCs) are widely used in clinical trials for bioregenerative medicine and in most cases, in vitro expansion and differentiation of these cells are required before application. Optimized expansion and differentiation protocols play a key role in the treatment outcome. 3D cell cultivation systems are more comparable to in vivo conditions and can provide both, more physiological MSC expansion and a better understanding of intercellular and cell-matrix interactions. Xeno-free cultivation conditions minimize risks of immune response after implantation. Human platelet lysate (hPL) appears to be a valuable alternative to widely used fetal calf serum (FCS) since no ethical issues are associated with its harvest, it contains a high concentration of growth factors and cytokines and it can be produced from expired platelet concentrate. In this study, we analyzed and compared proliferation, as well as osteogenic and chondrogenic differentiation of human adipose tissue-derived MSCs (hAD-MSC) using three different supplements: FCS, human serum (HS), and hPL in 2D. Furthermore, online monitoring of osteogenic differentiation under the influence of different supplements was performed in 2D. hPL-cultivated MSCs exhibited a higher proliferation and differentiation rate compared to HS- or FCS-cultivated cells. We demonstrated a fast and successful chondrogenic differentiation in the 2D system with the addition of hPL. Additionally, FCS, HS, and hPL were used to formulate Gelatin-methacryloyl (GelMA) hydrogels in order to evaluate the influence of the different supplements on the cell spreading and proliferation of cells growing in 3D culture. In addition, the hydrogel constructs were cultivated in media supplemented with three different supplements. In comparison to FCS and HS, the addition of hPL to GelMA hydrogels during the encapsulation of hAD-MSCs resulted in enhanced cell spreading and proliferation. This effect was promoted even further by cultivating the hydrogel constructs in hPL-supplemented media.

Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Platelet-rich plasma (PRP) and hyaluronic acid (HA) are 2 nonoperative treatment options for knee osteoarthritis (OA) that are supposed to provide symptomatic relief and help delay surgical intervention.

PURPOSE

To systematically review the literature to compare the efficacy and safety of PRP and HA injections for the treatment of knee OA.

STUDY DESIGN

Meta-analysis of level 1 studies.

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify level 1 studies that compared the clinical efficacy of PRP and HA injections for knee OA. The search phrase used was platelet-rich plasma hyaluronic acid knee osteoarthritis randomized. Patients were assessed via the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) scale. A subanalysis was also performed to isolate results from patients who received leukocyte-poor and leukocyte-rich PRP.

RESULTS

A total of 18 studies (all level 1) met inclusion criteria, including 811 patients undergoing intra-articular injection with PRP (mean age, 57.6 years) and 797 patients with HA (mean age, 59.3 years). The mean follow-up was 11.1 months for both groups. Mean improvement was significantly higher in the PRP group (44.7%) than the HA group (12.6%) for WOMAC total scores (P < .01). Of 11 studies based on the VAS, 6 reported PRP patients to have significantly less pain at latest follow-up when compared with HA patients (P < .05). Of 6 studies based on the Subjective IKDC outcome score, 3 reported PRP patients to have significantly better scores at latest follow-up when compared with HA patients (P < .05). Finally, leukocyte-poor PRP was associated with significantly better Subjective IKDC scores versus leukocyte-rich PRP (P < .05).

CONCLUSION

Patients undergoing treatment for knee OA with PRP can be expected to experience improved clinical outcomes when compared with HA. Additionally, leukocyte-poor PRP may be a superior line of treatment for knee OA over leukocyte-rich PRP, although further studies are needed that directly compare leukocyte content in PRP injections for treatment of knee OA.

Effect of platelet-rich plasma on healing in laser pilonidoplasty for pilonidal sinus disease

The aim of this study was to evaluate the effects of application of platelet-rich plasma in addition to laser pilonidoplasty for the treatment of pilonidal sinus. Twenty-five patients who were treated by laser pilonidoplasty for pilonidal sinus (group 1) and 25 patients who were treated by platelet-rich plasma in addition to laser pilonidoplasty (group 2) at this clinic were included in the study. Patients were classified according to the Irkorucu and Adana Numune's classification and treatment concept. Duration of stay of the patients in the hospital, time to start daily activities, duration of wound healing, recurrence, and complications were evaluated. Among the 50 patients included in the study, 41 (%82) were males and 9 (%18) were females. The mean age was 25.6 ± 2.4 years and 24.8 ± 3.8 years in groups 1 and 2, respectively. The locations of the pilonidal sinus were similar in the two groups. No statistically significant differences were found in the duration of hospital stay, duration of the procedure, time to return to work, and complication rates between the two groups. Nevertheless, duration of wound healing was 6.1 ± 2.3 and 4.1 ± 0.9 weeks in groups 1 and 2, respectively, and was shorter in group 2. Duration of wound healing was statistically significantly different in the two groups. We concluded in this study that application of platelet-rich plasma in addition to laser pilonidoplasty significantly shortens the time of wound healing.

Meta-analysis Comparing Platelet-Rich Plasma vs Hyaluronic Acid Injection in Patients with Knee Osteoarthritis

PURPOSE

The purpose of this meta-analysis was to compare platelet-rich plasma (PRP) and hyaluronic acid (HA) in patients with knee osteoarthritis (KOA).

METHODS

Randomized controlled trials (RCTs) comparing the use of PRP and HA in KOA patients were retrieved from each database from the establishment date to April 2018. Outcome measurements were the Western Ontario and McMaster Universities Arthritis Index (WOMAC), visual analog scale (VAS), International Knee Documentation Committee, and Lequesne Index scores and adverse events. The pooled data were evaluated with Review Manager 5.3.5.

RESULTS

Fifteen RCTs (N = 1,314) were included in our meta-analysis. The present meta-analysis indicated that PRP injections reduced pain more effectively than HA injections in patients with KOA at six and 12 months of follow-up, as evaluated by the WOMAC pain score; the VAS pain score showed a significant difference at 12 months. Moreover, better functional improvement was observed in the PRP group, as demonstrated by the WOMAC function score at three, six, and 12 months. Additionally, PRP injections did not display different adverse event rates compared with HA injections.

CONCLUSION

In terms of long-term pain relief and functional improvement, PRP injections might be more effective than HA injections as a treatment for KOA. The optimal dosage, the timing interval and frequency of injections, and the ideal treatment for different stages of KOA remain areas of concern for future investigations.

Systemic Review: Is an Intradiscal Injection of Platelet-Rich Plasma for Lumbar Disc Degeneration Effective?

Current studies evaluating the outcomes of intradiscal platelet-rich plasma (PRP) injections in degenerative disc disease (DDD) are limited. The purpose of this review was to determine if an intradiscal injection of PRP for degenerative discs results in a statistically significant improvement in clinical outcomes. A systematic review was performed using Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Level I-IV investigations of intradiscal PRP injections in DDD were sought in multiple databases. The Modified Coleman Methodology Score (MCMS) was used to analyze the methodological quality of the study. Only the outcome measurements used by more than 50% of the studies were included in the data analysis. The study heterogeneity and nature of evidence (mostly retrospective, non-comparative) precluded meta-analysis. Pre and post-injection pain visual analog scales (VAS) were compared using two sample Z-tests. Five articles (90 subjects, mean age 43.6 ± 7.7 years, mean follow-up 8.0 ± 3.6 months) were analyzed. Four articles were level IV evidence and one article was level II. Mean MCMS was 56.0 ± 10.3. There were 43 males and 37 females (10 unidentified). Pain VAS significantly improved following lumbar intradiscal PRP injection (69.7 mm to 43.3 mm; p<0.01). Two patients (2.2%) experienced lower extremity paresthesia after treatment. One patient (1.1%) underwent re-injection. No other complications were reported. In conclusion, intradiscal injection of PRP for degenerative discs resulted in statistically significant improvement in VAS with low re-injection and complication rates in this systematic review. It is unclear whether the improvements were clinically significant given the available evidence. The low level of evidence available (level IV) does not allow for valid conclusions regarding efficacy; however, the positive results suggest that further higher-quality studies might be of value.

Efficacy of Platelet-rich Plasma for Low Back Pain: A Systematic Review and Meta-analysis

BACKGROUND

 Platelet-rich plasma (PRP) may be beneficial for patients with low back pain. However, the results remain controversial. We conducted a systematic review and meta-analysis to explore the efficacy of PRP for low back pain.

METHODS

 PubMed, Embase, Web of Science, EBSCO, and Cochrane Library databases were searched systematically. Randomized controlled trials (RCTs) assessing the effect of PRP on low back pain were included. Two investigators independently searched articles, extracted data, and assessed the quality of included studies. The primary outcome was pain scores within 8 weeks. Meta-analysis was performed using the random-effects model.

RESULTS

 Three RCTs involving 131 patients were included in the meta-analysis. Overall, compared with control intervention for low back pain, PRP injection was found to reduce pain scores significantly (mean difference: - 1.47; 95% confidence interval [CI], - 2.12 to - 0.81; p < 0.0001), improve the number of patients with > 50% pain relief at 3 months (risk ratio [RR]: 4.14; 95% CI, 2.22-7.74; p < 0.00001), and offer relatively good patient satisfaction (RR: 1.91; 95% CI, 1.04-3.53; p = 0.04). No increase in adverse events was reported after PRP injection (RR: 1.92; 95% CI, 0.94-3.91; p = 0.07).

CONCLUSIONS

 Compared with control intervention for low back pain, PRP injection was found to improve pain relief and patient satisfaction significantly with no increase in adverse events.

Progenitor Cells Activated by Platelet Lysate in Human Articular Cartilage as a Tool for Future Cartilage Engineering and Reparative Strategies

Regenerative strategies for human articular cartilage are still challenging despite the presence of resident progenitor cell population. Today, many efforts in the field of regenerative medicine focus on the use of platelet derivatives due to their ability to reactivate endogenous mechanisms supporting tissue repair. While their use in orthopedics continues, mechanisms of action and efficacy need further characterization. We describe that the platelet lysate (PL) is able to activate chondro-progenitor cells in a terminally differentiated cartilage tissue. Primary cultures of human articular chondrocytes (ACs) and cartilage explants were set up from donor hip joint biopsies and were treated in vitro with PL. PL recruited a chondro-progenitors (CPCs)-enriched population from ex vivo cartilage culture, that showed high proliferation rate, clonogenicity and nestin expression. CPCs were positive for in vitro tri-lineage differentiation and formed hyaline cartilage-like tissue in vivo without hypertrophic fate. Moreover, the secretory profile of CPCs was analyzed, together with their migratory capabilities. Some CPC-features were also induced in PL-treated ACs compared to fetal bovine serum (FBS)-control ACs. PL treatment of human articular cartilage activates a stem cell niche responsive to injury. These facts can improve the PL therapeutic efficacy in cartilage applications.

Therapeutic Potential of Dental Pulp Stem Cells and Leukocyte- and Platelet-Rich Fibrin for Osteoarthritis

Osteoarthritis (OA) is a degenerative and inflammatory joint disorder with cartilage loss. Dental pulp stem cells (DPSCs) can undergo chondrogenic differentiation and secrete growth factors associated with tissue repair and immunomodulation. Leukocyte- and platelet-rich fibrin (L-PRF) emerges in regenerative medicine because of its growth factor content and fibrin matrix. This study evaluates the therapeutic application of DPSCs and L-PRF in OA via immunomodulation and cartilage regeneration. Chondrogenic differentiation of DPSCs, with or without L-PRF exudate (ex) and conditioned medium (CM), and of bone marrow-mesenchymal stem cells was compared. These cells showed differential chondrogenesis. L-PRF was unable to increase cartilage-associated components. Immature murine articular chondrocytes (iMACs) were cultured with L-PRF ex, L-PRF CM, or DPSC CM. L-PRF CM had pro-survival and proliferative effects on unstimulated and cytokine-stimulated iMACs. L-PRF CM stimulated the release of IL-6 and PGE2, and increased MMP-13, TIMP-1 and IL-6 mRNA levels in cytokine-stimulated iMACs. DPSC CM increased the survival and proliferation of unstimulated iMACs. In cytokine-stimulated iMACs, DPSC CM increased TIMP-1 gene expression, whereas it inhibited nitrite release in 3D culture. We showed promising effects of DPSCs in an in vitro OA model, as they undergo chondrogenesis in vitro, stimulate the survival of chondrocytes and have immunomodulatory effects.

How to Choose Platelet-Rich Plasma or Hyaluronic Acid for the Treatment of Knee Osteoarthritis in Overweight or Obese Patients: A Meta-Analysis

Objective

The purpose of this meta-analysis was to determine whether platelet-rich plasma (PRP) was better than hyaluronic acid (HA) for the treatment of knee osteoarthritis (OA) in overweight or obese patients.

Design

Two reviewers independently used the keywords combined with free words to search English-based electronic databases according to Cochrane Collaboration guidelines, such as PubMed, Embase, ScienceDirect, and Cochrane library. The pooled data were analyzed using RevMan 5.3.

Results

Ten randomized controlled trials (RCTs) with 1096 patients were included. During the first two months of follow-up, there was no significant difference between the two groups. At the 3rd, 6th, and 12th months of follow-up, the pooled analysis showed that PRP was better than HA for the treatment of knee OA in overweight or obese patients. There were significant differences between the two groups at Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) total score (3 months: MD = -1.35, [95% CI: -2.19 to -0.50], P=0.002, I 2 = 0%; 6 months: MD = -7.62, [95% CI: -13.51 to -1.72], P=0.01, I 2 = 88%; 12 months: MD = -12.11, [95% CI: -20.21 to -4.01], P=0.003, I 2 = 94%).

Conclusions

For overweight or obese patients with knee OA, intra-articular injection of PRP in a short time was not necessarily superior to HA, but long-term use was better than HA in pain and functional relief.

Combination of low intensity electromagnetic field with chondrogenic agent induces chondrogenesis in mesenchymal stem cells with minimal hypertrophic side effects

Background: There are different methods to develop in vitro neo-chondral tissues from adipose-derived stem cells (ADSCs). Application of electromagnetic field (EMF) on ADSCs is one of popular approaches, which results in chondrogenesis. If chondrogenic impact of EMF on ADSCs is supposed to be generalized as a protocol in translational medicine field, possible emergence of early or late hypertrophic maturation, mineralization and inflammatory side effects in chondrogenically differentiating ADSCs should be considered.Methods: The advent of chondrogenic and hypertrophic markers by differentiated cells under standard, platelet-rich plasma (PRP)-based or EMF treatments were monitored. Along with monitoring the expressions of chondrogenic markers, inflammatory and hypertrophic markers, VEGF/TNFα secretion, calcium deposition and ALP activity were evaluated.Results: Accordingly, treatment with %5 PRP results in higher GAG production, enhanced SOX9 transcription, lowered TNFα and VEGF secretions compared to other treatments. Although PRP up-regulates miR-146a and miR-199a in early and late stages of chondrogenesis, respectively, application of EMF + PRP down regulates miR-101 and -145 while up-regulates miR-140 and SOX9 expression.Conclusion: Comparing our results with previous reports suggests that presented EMF-ELF in this study with f = 50 Hz, EMF intensity of less than 30 mT, and 5% PRP (v/v), would facilitate chondrogenesis via mesenchymal stem cells with minor inflammation and hypertrophic maturation.Abbreviations: MSCs: mesenchymal stem cells; TGFβ: transforming growth factor-beta; PRP: platelet-rich plasma; ELF-EMF: extremely low-frequency electromagnetic fields; GAGs: glycosaminoglycans; ADSCs: adipose-derived stem cells; VEGF: vascular endothelial growth factor; TNFα: tumor necrosis factor alpha; ALP: alkaline phosphatase.

A randomized controlled trial of effectiveness of platelet-rich plasma gel and regular dressing on wound healing time in pilonidal sinus surgery: Role of different affecting factors

Background

The aim of this study was to assess the possible association between different factors such as age, sex, antibiotic consumption duration, angiogenesis and pain and “acceleration of wound healing” in pilonidal sinus patients after treating with platelet-rich plasma (PRP).

Methods

In this clinical trial, 110 patients were randomly divided into treatment arm and control group. After surgery, control group underwent classic wound dressing and the treatment arm experienced PRP gel therapy. Before achieving complete healing, wound incisional biopsy was performed in order to evaluate angiogenesis. During the study, other data such as pain and antibiotic consumption duration were also collected. Wound healing time of pilonidal sinus disease was analyzed using Extended and Stratify Cox model. Data were analyzed using R and STATA software. p<0.05 were considered statistically significant.

Results

The average wound volume was calculated 41.9 ± 8.01 cc in the controls and 42.35 ± 10.81 in the treatment arm group. The mean of healing time was 8.7 ± 1.18, 4.8 ± 0.87 weeks for control and treatment arm, respectively. There was a significant and strong negative association between healing time and wound volume (p<0.01). Moreover, a significant negative association was found between pain duration and angiogenesis (p<0.001), a strong positive significant association was found between healing time of the treatment arms (p<0.01), and the rate of wound healing for participants treated with PRP gel was 37.2 times more than that of controls.

Conclusion

Authors hope for these finding to help the future researches to more thoroughly focus on the mentioned factors in order to find a suitable strategy for wound healing using PRP.

Use of Ultrasound-Guided Platelet-Rich Plasma Injection of the Sacroiliac Joint as a Treatment for Chronic Low Back Pain

Back pain and its associated complications are of increasing importance among military members. The sacroiliac joint (SIJ) is a common source of chronic low back pain (LBP) and functional disability. Many patients suffering from chronic LBP utilize opioids to help control their symptoms. Platelet-rich plasma (PRP) has been used extensively to treat pain emanating from many different musculoskeletal origins; however, its use in the SIJ has been studied only on a limited basis. The patient in this case report presented with chronic LBP localized to the SIJ and subsequent functional disability managed with high-dose opioids. After failure of traditional treatments, she was given an ultrasound-guided PRP injection of the SIJ which drastically decreased her pain and disability and eventually allowed for complete opioid cessation. Her symptom relief continued 1 year after the injection. This case demonstrates the potential of ultrasound-guided PRP injections as a long-term treatment for chronic LBP caused by SIJ dysfunction in military service members, which can also aid in the weaning of chronic opioid use.

Progress and Applications of Polyphosphate in Bone and Cartilage Regeneration

Patients with bone and cartilage defects due to infection, tumors, and trauma are quite common. Repairing bone and cartilage defects is thus a major problem for clinicians. Autologous and artificial bone transplantations are associated with many challenges, such as limited materials and immune rejection. Bone and cartilage regeneration has become a popular research topic. Inorganic polyphosphate (polyP) is a widely occurring biopolymer with high-energy phosphoanhydride bonds that exists in organisms from bacteria to mammals. Much data indicate that polyP acts as a regulator of gene expression in bone and cartilage tissues and exerts morphogenetic effects on cells involved in bone and cartilage formation. Exposure of these cells to polyP leads to the increase of cytokines that promote the differentiation of mesenchymal stem cells into osteoblasts, accelerates the osteoblast mineralization process, and inhibits the differentiation of osteoclast precursors to functionally active osteoclasts. PolyP-based materials have been widely reported in in vivo and in vitro studies. This paper reviews the current cellular mechanisms and material applications of polyP in bone and cartilage regeneration.

Platelet-Rich Fibrin Scaffolds for Cartilage and Tendon Regenerative Medicine: From Bench to Bedside

Nowadays, research in Tissue Engineering and Regenerative Medicine is focusing on the identification of instructive scaffolds to address the requirements of both clinicians and patients to achieve prompt and adequate healing in case of injury. Among biomaterials, hemocomponents, and in particular Platelet-rich Fibrin matrices, have aroused widespread interest, acting as delivery platforms for growth factors, cytokines and immune/stem-like cells for immunomodulation; their autologous origin and ready availability are also noteworthy aspects, as safety- and cost-related factors and practical aspects make it possible to shorten surgical interventions. In fact, several authors have focused on the use of Platelet-rich Fibrin in cartilage and tendon tissue engineering, reporting an increasing number of in vitro, pre-clinical and clinical studies. This narrative review attempts to compare the relevant advances in the field, with particular reference being made to the regenerative role of platelet-derived growth factors, as well as the main pre-clinical and clinical research on Platelet-rich Fibrin in chondrogenesis and tenogenesis, thereby providing a basis for critical revision of the topic.

Interventional radiology techniques for pain reduction and mobility improvement in patients with knee osteoarthritis

Osteoarthritis of the knee is the most common cause of chronic knee pain being more prevalent in middle-aged and elderly patients. Symptomatic patients complain of pain and mobility impairment. Therapeutic armamentarium includes physical therapy, oral pharmacologic therapy, intra-articular injections, nerve ablation or modulation, trans-catheter arterial embolization, minimally invasive arthroscopic treatment and partial or total knee arthroplasty. Interventional radiology therapies for knee osteoarthritis include intra-articular injections, neurotomy and neuromodulation techniques as well as transcatheter intra-arterial therapies. These therapies aim to control pain and inflammation, improve mobility and function whilst the novel cell-based therapies have the potential for bone and cartilage regenerative repair facilitating the delay to surgery. The purpose of this review is to illustrate the technical aspects, the indications and the methodology of local therapies for knee osteoarthritis performed by interventional radiologists and provide current evidence.

The use of PRP injections in the management of knee osteoarthritis

Osteoarthritis (OA) is a degenerative disease involving joint damage, an inadequate healing response and progressive deterioration of the joint architecture that commonly affects the knee and/or hip joints. It is a major world public health problem and is predicted to increase rapidly with an ageing population and escalating rate of obesity. Autologous blood-derived products possess much promise in the repair and regeneration of tissue and have important roles in inflammation, angiogenesis, cell migration and metabolism in pathological conditions, including OA. Utilising platelet-rich plasma (PRP) to treat tendon, ligament and skeletal muscle has shown variable results across many studies with the current evidence base for the efficacy of PRP in treating sports injuries remaining inconclusive. More uniformly positive results have been observed by various studies for PRP in OA knee in comparison to hyaluronic acid, other intra-articular injections and placebo than in other musculoskeletal tissue. However, methodological concerns as well as satisfactory PRP product classification prevent the true characterisation of this treatment. Thus, further research is required to investigate how leukocyte inclusion, activation and platelet concentration affect therapeutic efficacy. Furthermore, the optimisation of timing, dosage, volume, frequency and rehabilitation strategies need to be ascertained. For knee OA management, these concerns must be addressed before this promising treatment can be widely implemented.

Allogeneic platelet rich plasma serves as a scaffold for articular cartilage derived chondroprogenitors

Limited self-restorative ability of the cartilage has necessitated the use of cell and tissue engineering based therapies. Recent advances in the isolation, expansion and characterization of articular cartilage derived chondroprogenitors(CPs) has gained popularity in its role for cartilage repair. Platelet rich plasma (PRP) is a reliable biological scaffold for in-vitro and in-vivo studies with reported therapeutic applications in cartilage and bone pathologies. The aim of this study was to evaluate whether human allogeneic PRP could serve as a biological scaffold for chondroprogenitors (CPs) in cartilage repair. CPs were isolated from the superficial layer of three osteoarthritic knee joints by fibronectin adhesion assay and characterized using flow cytometric analysis. Allogeneic citrated blood was harvested from three subjects to obtain PRP. CPs at a concentration of one million cells per ml were gelled with PRP using calcium chloride. The PRP-CP scaffolds were subjected for adipogeneic, osteogenic, chondrogeneic differentiation and processed for post differentiation-staining studies (Oil Red O, Von Kossa, Alcian blue staining), immunofluorescence (collagen II) and live dead assays (Calcein AM-Ethidium Homodimer). We show that PRP was able to sustain CP cell viability and differentiate towards adipogenic, osteogenic and chondrogenic lineage under appropriate culture conditions. We also noted positive extracellular matrix production in PRP-CP scaffolds cultured without chondrogenic supplementation. Our results suggest that PRP could be a promising bio-active scaffold due to its synergistic effect in supporting cell proliferation, maintaining cell viability and favoring extracellular matrix production. PRP can be used as biological scaffold for the delivery of CPs in cartilage healing.

Intra-articular Injection of Platelet-Rich Plasma Is Superior to Hyaluronic Acid or Saline Solution in the Treatment of Mild to Moderate Knee Osteoarthritis: A Randomized, Double-Blind, Triple-Parallel, Placebo-Controlled Clinical Trial

PURPOSE

To prospectively compare the efficacy of intra-articular injections of platelet-rich plasma (PRP) and hyaluronic acid (HA) with a sham control group (normal saline solution [NS]) for knee osteoarthritis in a randomized, dose-controlled, placebo-controlled, double-blind, triple-parallel clinical trial.

METHODS

A total of 87 osteoarthritic knees (53 patients) were randomly assigned to 1 of 3 groups receiving 3 weekly injections of either leukocyte-poor PRP (31 knees), HA (29 knees), or NS (27 knees). The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and International Knee Documentation Committee (IKDC) subjective score were collected at baseline and at 1, 2, 6, and 12 months after treatment. Data were analyzed using generalized estimating equations.

RESULTS

All 3 groups showed statistically significant improvements in both outcome measures at 1 month; however, only the PRP group sustained the significant improvement in both the WOMAC score (63.71 ± 20.67, increased by 21%) and IKDC score (49.93 ± 17.74, increased by 40%) at 12 months. For the intergroup comparison, except for the first month, there was a statistically significant difference between the PRP and NS groups in both scores throughout the study duration (regression coefficients of 8.72 [P = .0015], 7.94 [P = .0155], and 11.92 [P = .0014] at 2, 6, and 12 months, respectively, for WOMAC score, and 9.1 [P = .0001], 10.28 [P = .0002], and 13.97 [P < .0001], respectively, for IKDC score). There was no significant difference in both functional outcomes between the HA and NS groups at any time point. Only the PRP group reached the minimal clinically important difference in the WOMAC score at every evaluation (15%, 21%, 18%, and 21% at 1, 2, 6, and 12 months, respectively) and the minimal clinically important difference in the IKDC score at 6 months (improvement of 11.6).

CONCLUSIONS

Intra-articular injections of leukocyte-poor PRP can provide clinically significant functional improvement for at least 1 year in patients with mild to moderate osteoarthritis of the knee.

LEVEL OF EVIDENCE

Level I, randomized controlled single-center trial.

Current Concepts and Future Directions of Minimally Invasive Treatment for Knee Pain

PURPOSE OF REVIEW

The purpose of this paper is to review the percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.

RECENT FINDINGS

Corticosteroid injection and viscosupplementation have been the most studied, but there is still no consensus about their value. Thermal nerve ablation, including both radiofrequency ablation and cryoneurolysis, is a promising new modality of therapy that may increase in clinical use given current data showing favorable outcomes. Of the future therapies that are currently under investigation, synovial embolization via the geniculate arteries represents an exciting new approach that may soon be available clinically. There are various percutaneous interventions available for the treatment of osteoarthrosis of the knee that address pain and prolong the time to arthroplasty.