Platelet-Rich Plasma for the Management of Hip and Knee Osteoarthritis

Clinical Effect of Bushen Huoxue Method Combined with Platelet-Rich Plasma in the Treatment of Knee Osteoarthritis and Its Effect on IL-1, IL-6, VEGF, and PGE-2

Objective

To observe the clinical efficacy of the Bushen Huoxue method combined with platelet-rich plasma (PRP) in the treatment of knee osteoarthritis (KOA) and its effect on serum and joint fluid interleukin-1 (IL-1), interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), and prostaglandin E2 (PGE-2).

Methods

A total of 64 cases of KOA diagnosed and treated from January 2020 to January 2021 were randomly divided into research group and control group, with 32 cases in each group. The control group was treated with PRP, and the research group took the prescription of the Bushen Huoxue method on the basis of the control group. The clinical efficacy was assessed according to the criteria in "the diagnosis and Treatment of osteoarthritis," osteoarthritis index score and pain visual analogue score (VAS). Serum and articular fluid VAS, IL-1, IL-6, VEGF, and PGE-2 levels were detected by the enzyme-linked immunosorbent assay (ELISA).

Results

The clinical effective rate of the research group was 93.8%, which was significantly higher than that of the control group (90.6%). There was no significant difference in the scores of osteoarthritis index between the two groups before treatment, but the scores of both groups decreased after treatment and was lower in the research group than those in the control group. VAS was significantly decreased in two groups after treatment and it was lower in the research group than that in the control group. After treatment, the levels of IL-1, IL-6, and PGE-2 in serum and articular fluid all indexes were decreased, and the levels in the research group were lower than those in the control group.

Conclusions

PRP joint cavity injection combined with oral administration of Bushen Huoxue prescription, and PRP joint cavity injection alone can improve the efficacy of KOA, relieve knee pain, and promote the recovery of knee function. The mechanism may be related to the reduction of IL-1, IL-6, VEGF levels, and PGE-2 levels in the serum and joint fluid. However, the efficacy of combination therapy was superior to PRP alone.

The use of intra-articular platelet rich plasma for the symptomatic management of osteoarthritis of the knee: a pilot study

BACKGROUND

Osteoarthritis of the knee is a chronic inflammatory condition resulting in significant patient disability, with intra-articular platelet rich plasma (PRP) injections having shown potential to improve symptomatic outcomes. This retrospective cohort pilot study aimed to observe whether PRP injections were beneficial in the symptomatic management of knee osteoarthritis in an Australian population, based on patient reported outcomes. An additional aim was to observe for an association between the number of injections and patient characteristics, such as body mass index, age, sex and radiologically determined severity of the disease.

METHODS

The cohort was drawn from those who attended Ballarat Orthopaedic and Sports Medicine for PRP injections and who had completed the appropriate pre- and post-injection Western Ontario and McMaster Universities Arthritis Index (WOMAC) questionnaire. WOMAC scores were analysed to observe for any difference following a course of PRP injections.

RESULTS

The data suggest that the use of PRP improved patient reported WOMAC scores. Additionally, it was shown that two injections had a greater effect than one injection, with a third injection providing no further benefit. Finally, there was an association with lower WOMAC scores post PRP therapy amongst male participants compared to female participants.

CONCLUSION

These results suggest two PRP injections are optimal for the symptomatic management of knee osteoarthritis, identifying a need for further prospective research in this Australian population.

Platelet-rich plasma (PRP) augmentation does not result in more favourable outcomes in arthroscopic meniscal repair: a meta-analysis

Background

The efficacy and safety of platelet-rich plasma (PRP) augmentation for arthroscopic meniscal repair is controversial. This meta-analysis compared arthroscopic meniscal repair performed in isolation or augmented with PRP.

Methods

The present study was conducted according to PRISMA 2020 guidelines. Pubmed, Web of Science, Google Scholar and Embase were accessed in August 2021. All the clinical trials which compared arthroscopic meniscal repair performed in isolation or augmented with PRP were included.

Results

Eight hundred thirty-seven patients were included: 38% (318 of 837 patients) were women; the mean age of the patients was 35.6 (range, 20.8–64.3) years; the mean follow-up was 26.2 (range, 6–54) months. Similarity was found in analogue scale (VAS) (P = 0.5) and Lysholm (P = 0.9), and International Knee Documentation Committee (IKDC) scores (P = 0.9). Similarity was found in the rate of failure (P = 0.4) and rate of revision (P = 0.07).

Conclusion

The current published scientific evidence does not support PRP augmentation for arthroscopic meniscal repair.

Editorial Commentary: Intraoperative Platelet-Rich Plasma Injections for Open-Wedge High Tibial Osteotomies Effectively Improve Clinical Outcomes and Minimal Medial Joint Space Width: An Orthobiologic Application

Osteoarthritis is a significant cause of morbidity and mortality involving the knee joint, and high tibial osteotomy is becoming more commonly used to treat severe knee osteoarthritis. In addition, the best management and therapies to mitigate osteoarthritis symptoms and progression may include biologic injections, as we focus on more than just structural abnormalities but also on the inflammatory environment in the joint. These therapies include platelet-rich plasma, bone marrow aspirate concentrate, cell-based therapies, adipose-derived stromal cells, and amniotic suspension allografts. Recent research supports a promising therapy: combined high tibial osteotomy and intraoperative, intraarticular platelet-rich plasma injection.

Comparisons of Ultrasound-Guided Platelet-Rich Plasma Intra-Articular Injection and Extracorporeal Shock Wave Therapy in Treating ARCO I–III Symptomatic Non-Traumatic Femoral Head Necrosis: A Randomized Controlled Clinical Trial

Background and Objective

Osteonecrosis of the femoral head (ONFH) is a devastating disease, and there is some evidence that extracorporeal shock wave therapy (ESWT) and intra-articular platelet-rich plasma (PRP) injection might alleviate pain and improve joint function in individuals with ONFH. The objective of this study was to compare the effectiveness and safety of PRP and ESWT in symptomatic ONFH patients.

Methods

A total of 60 patients aged 40–79 with unilateral ONFH at Association Research Circulation Osseous (ARCO) stages I, II, and III were randomly assigned to the PRP (N=30) or the ESWT group (N=30). Four treatment sessions were provided in both groups. Assessments were performed at baseline, and 1-, 3-, 6-, and 12-month. Primary outcomes were measured by the visual analogue scale (VAS), and pressure pain thresholds (PPTs). Secondary outcomes were assessed by Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Harris Hip Score (HHS), and magnetic resonance imaging (MRI). The linear mixed-model analysis was used to evaluate the differences between groups and within groups and the “group by time” interaction effects.

Results

There were significant differences between groups in terms of changes over time for VAS, PPTs, WOMAC, and HHS since 3-month and maintained up to 12-month (P<0.05, except for PPTs at 12-month). The simple main effects showed that the patients in PRP group had greater improvements in VAS (mean difference = −0.82, 95% CI [−1.39, −0.25], P=0.005), WOMAC (mean difference = −4.19, 95% CI [−7.00, −1.37], P=0.004), and HHS (mean difference = 5.28, 95% CI [1.94, 8.62], P=0.002). No related adverse events were reported.

Conclusion

This study supported the effectiveness and safety of both the PRP injection and ESWT in treating ONFH patients. For symptomatic patients with ONFH, intra-articular PRP injection appeared superior to ESWT in pain relief and functional improvement.

Intra-articular placebo effect in the treatment of knee osteoarthritis: a survey of the current clinical evidence

Knee osteoarthritis (KOA) is a debilitating disease characterized by chronic pain, stiffness, and decreased mobility. Intra-articular injectable therapies show good clinical efficacy in improving symptoms; however, these therapies and their comparators (intra-articular saline) have been associated with a large underlying placebo effect. We aimed to describe the existing evidence on the challenges, hypotheses, and potential solutions to mitigate the intra-articular placebo effect in clinical trials in KOA. A targeted literature review was conducted by searching Embase, MEDLINE®, and CENTRAL using predefined study selection criteria. All eligible studies identified were extracted for relevant data, and results were narratively summarized. Forty-three studies were included following screening. Challenges associated with the intra-articular placebo effect included its ability to mask the comparative efficacy of active treatments in trials (n = 7 studies), long-lasting effects (up to 6 months; n = 3), and substantial variation of placebo effect sizes across populations (n = 3). Hypotheses for the mechanism of the placebo effect included aspiration of synovial fluid during administration (n = 6) and dilution of inflammatory mediators (n = 2). Factors affecting the placebo effect size were more invasive routes of administration (e.g., injection versus oral; n = 4) and patient expectations (n = 2). Proposed solutions included the suggestion for readers to weigh the relevance of clinical trial evidence against the presence of large underlying placebo effects (n = 9), discontinuation of intra-articular saline as an appropriate placebo (n = 5), and inclusion of 'no treatment' or sham injection as a control (n = 4). The intra-articular placebo effect is a well-documented occurrence in KOA clinical trials, and it is suggested that it be accounted for when designing randomized controlled trials. Awareness and understanding of the intra-articular placebo effect in KOA are required for fair interpretation of clinical trial evidence.

Healthcare and Scientific Treatment of Knee Osteoarthritis

Knee osteoarthritis is a chronic degenerative disease companied with chronic knee pain and dysfunction. However, the etiology and pathogenesis of knee osteoarthritis were unclear. Currently, age, diet, trauma, obesity, and inheritance are the main risk factors. The major pathological hallmarks of knee osteoarthritis included subchondral bone sclerosis, articular cartilage degeneration, arthrosynovitis, and osteophyte. With the acceleration of the aging process in China, the treatment of knee arthritis and the methods to improve the quality of life have become the focus of medical staff. Currently, therapies in clinical practice include surgery and nonoperative treatment; however, the clinical effects of different individuals at different stages will still be very different. This article reviews the recent advances in the treatment of knee osteoarthritis from three aspects: nonsurgical treatment, surgical treatment, and modern new medical means.

Serum Levels of VWF, t-PA, TNF-α, and ICAM-1 in Patients Receiving Hemocoagulase Combined with Platelet-Rich Plasma during Total Hip Replacement

Objectives

This study aimed to investigate the effect of hemocoagulase combined with platelet-rich plasma (PRP) in total hip replacement (THR) on reducing bleeding and improving knee joint function in the patients with osteoarthritis.

Methods

From February 2018 to February 2020, 80 osteoarthritis patients undergoing THR were included in the study, of which 40 cases were treated with PRP and hemocoagulase (test group) in the joint capsule in THR and the other 40 cases received saline and thrombin in the joint capsule after THR (control group). Postoperative drainage and corresponding functional exercise were performed for the two groups 12 hours after operation. The outcome measures including operation time, soft-tissue release, blood routine, drainage volume, perioperative blood loss, postoperative incision inflammation, deep vein thrombosis (DVT), and range of motion (ROM) of the joint were recorded.

Results

The hemoglobin and hematocrit values of the test group on the second postoperative day were significantly higher than those of the control group (P < 0.05). The postoperative drainage volume and perioperative blood loss were significantly lower than those of the control group (P < 0.05). The test group was better than the control group in the ROM of the joint at 7 and 15 days after the operation (P < 0.05). A lower value of prothrombin time and activated partial thromboplastin time was revealed in the test group compared with the control group (P < 0.05). No significant difference in the operation time, intraoperative soft-tissue release, postoperative incision inflammation, incidence of DVT, incidence of deep infection, and ROM at day 90 after THR was found in the two groups (P > 0.05).

Conclusions

The application of hemocoagulase combined with PRP in THR can reduce perioperative blood loss, increase wound healing speed and quality, and improve coagulation and immune function. It is a safe and effective method for the patients with knee osteoarthritis who underwent THR.

Intra-Articular Platelet-Rich Plasma Injections in Knee Osteoarthritis: A Review of Their Current Molecular Mechanisms of Action and Their Degree of Efficacy

Knee osteoarthritis (OA) is estimated to affect more than 10% of the population, with a lifetime risk of 45%. Contemporary guidelines advise control of body weight, therapeutic physical exercise, drug treatment (oral non-steroidal anti-inflammatory drugs, paracetamol, opioids), and mechanical aids (walking aids, braces, orthoses). Nevertheless, these treatments typically have only short-term benefits. Intra-articular corticosteroids are typically advised, but only for short-term pain alleviation, given that their benefits last only a few weeks. The efficacy of hyaluronic acid is controversial. When the aforesaid options fail, total knee arthroplasty is generally recommended as an efficacious treatment. However, it is costly and can involve medical and postoperative complications. Therefore, determining alternate safe and effective treatments for knee OA is paramount. Platelet-rich plasma (PRP) has lately been investigated for the treatment of knee OA. This article reviews recent knowledge concerning PRP’s molecular mechanisms of action. The effectiveness of intra-articular PRP injections in the knee joint remains controversial, although most recent publications show pain alleviation in the short term. Orthopedic surgeons treating people with knee OA are becoming increasingly interested in PRP, despite indecisive clinical data and basic science information. Further studies comparing PRP with placebo are required.

Applications of the regenerative capacity of platelets in modern medicine

Platelets produce platelet growth factors such as PDGF, IGF-1, EGF-, HGF, TGFβ, bFGF, and VEGF, which are crucial in regulating all stages of the wound healing process. The source of these substances is platelet-rich plasma (PRP). Over the past five decades, the interest and use of the regenerative properties of platelets have increased significantly in many different fields of medicine around the world. PRP and PRF plate preparations are used in: 1. Dentistry (they reduce bleeding, facilitate and accelerate soft tissue healing and bone regeneration - FGF 2, IGF-1, IGF-2, TGF-β1, and PDGF); 2. Sports medicine - IGF-1, IGF-2, TGF-β, VEGF, PDGF and bFGF, EGF); 3. dermatology and cosmetology (treatment of alopecia, hair reconstruction - FGF-7, HGF, acne scars, skin rejuvenation and regeneration, treatment of chronic and poorly healing wounds, burns, and acquired vitiligo); 4. Gynecology and reproductive medicine (treatment of infertility, erectile dysfunction - PDGF-β, TGF-β, IGF-1, in sexual dysfunction - PDGF, in vaginal atrophy); 5 Ophthalmology (in the healing of corneal epithelial wounds, in the treatment of dormant corneal ulcers, dry eye syndrome and the reconstruction of the corneal surface; 6. Neurology (regeneration of neurons, pain alleviation, and clinical symptoms - TGF-β 1, IGF-1, PDGF, VEGF) and FGF). Platelet-rich plasma therapy is a very interesting alternative and complement to traditional methods of treatment. However, the potential for using platelets is still not fully understood. The composition of platelet-rich plasma depends on many factors that may affect its use's efficacy and clinical benefits. Further research is necessary to standardize PRP delivery's preparation procedures and methods for a specific disease entity or clinical case.

PRP Injections for the Treatment of Knee Osteoarthritis: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

To evaluate effectiveness, in terms of patient-reported outcome measures, of platelet-rich plasma (PRP) injections for knee osteoarthritis compared to placebo and other intraarticular treatments.

DESIGN

PubMed, Cochrane Library, Scopus, Embase, Web of Science, as well as the gray literature were searched on January 17, 2020. Randomized controlled trials (RCTs) comparing PRP injections with placebo or other injectable treatments, in any language, on humans, were included. Risk of bias was assessed following the Cochrane guidelines; quality of evidence was graded using the GRADE guidelines.

RESULTS

Thirty-four RCTs, including 1403 knees in PRP groups and 1426 in control groups, were selected. WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) score favored PRP, with a statistically and clinically significant difference versus placebo at 12-month follow-up (P = 0.02) and versus HA (hyaluronic acid) at 6-month (P < 0.001) and 12-month (P < 0.001) follow-ups. A clinically significant difference favoring PRP versus steroids was documented for VAS (Visual Analogue Scale) pain (P < 0.001), KOOS (Knee Injury and Osteoarthritis Outcome Score) pain (P < 0.001), function in daily activities (P = 0.001), and quality of life (P < 0.001) at 6-month follow-up. However, superiority of PRP did not reach the minimal clinically important difference for all outcomes, and quality of evidence was low.

CONCLUSIONS

The effect of platelet concentrates goes beyond its mere placebo effect, and PRP injections provide better results than other injectable options. This benefit increases over time, being not significant at earlier follow-ups but becoming clinically significant after 6 to 12 months. However, although substantial, the improvement remains partial and supported by low level of evidence. This finding urges further research to confirm benefits and identify the best formulation and indications for PRP injections in knee OA.

Transarterial Embolization for the Treatment of Chronic Musculoskeletal Pain: A Systematic Review of Indications, Safety, and Efficacy

Objective

The study objective was to evaluate the safety and efficacy of transcatheter arterial “embolization” (TAE) in the treatment of chronic “musculoskeletal pain” refractory to standard therapy.

Methods

PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for original research articles evaluating TAE in patients with musculoskeletal conditions from database inception to January 21, 2020. Search terms employed were as follows: “embolization”, “pain”, “knee osteoarthritis”, joint replacement, epicondylitis, tenderness, inflammation, WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), microspheres, Embozene, geniculate artery, neovascularity, transcatheter, embolic, imipenem/cilastatin sodium, angiogenesis, and “musculoskeletal”. Studies involving particle “embolization” for painful musculoskeletal conditions were included. Studies of TAE for hemarthrosis or malignancy‐related “musculoskeletal pain” were excluded.

Results

The primary search yielded 1,099 sources; 7 articles and 4 abstracts were included for data extraction. All were cohorts or case series, with low risk of bias and moderate to poor level of evidence. Heterogeneity between studies was high, precluding meta‐analysis. The reviewed studies reported the safety and efficacy of TAE for the treatment of “knee osteoarthritis”; adhesive capsulitis of the shoulder; tendinopathy/enthesopathy of the knee, shoulder, elbow, and ankle; and cervical myalgia. All TAEs were reported as technically successful without major complications or subsequent serious adverse events, including no reported osteonecrosis, cutaneous ulceration, limb ischemia, cartilage degeneration, or myotendinous injury. TAE significantly reduced pain and improved function for all of the treated conditions, with durable response up to 24 months post procedure.

Conclusion

TAE appears to be a safe and effective treatment for some types of chronic refractory “musculoskeletal pain”. Randomized placebo‐controlled studies are necessary to confirm these findings.

Intraarticular Platelet Rich Plasma vs Corticosteroid Injections for Sacroiliac Joint Pain-a Double Blinded, Randomized Clinical Trial

OBJECTIVE

Using stringent inclusion criteria, a double-blinded study protocol, and fluoroscopic guided injections, we compare intraarticular sacroiliac joint platelet rich plasma injections to intraarticular steroids.

DESIGN

Double-blind, randomized controlled trial.

SETTING

Two large university-based interdisciplinary spine centers.

SUBJECTS

26 patients after positive diagnostic block (>80% relief).

METHODS

Subjects who a positive diagnostic block were randomized to either undergo a fluoroscopically-guided intra-articular injection of steroid or platelet rich plasma injection. Follow-up was at 1-month, 3 months, and 6-months. Outcomes included level of pain as indicated on a 0- to 100-mm Numeric Pain Rating Scale and functional disability score using the Oswestry Disability Index (ODI).

RESULTS

At one, three, and six months, both groups improved, however subjects who received steroid injections reported lower pain scores than subjects who received platelet rich plasma. Using categorical data, we observed significantly more responders (defined as pain scores which improved by 50% or more from baseline) at one and three months in the group that received steroids compared to the group that received platelet rich plasma.

CONCLUSION

While both groups showed improvements in pain and function, the steroid group had significantly greater response and significantly more responders than the PRP group.

Effect of Intra-articular Platelet-Rich Plasma vs Placebo Injection on Pain and Medial Tibial Cartilage Volume in Patients With Knee Osteoarthritis: The RESTORE Randomized Clinical Trial

IMPORTANCE

Most clinical guidelines do not recommend platelet-rich plasma (PRP) for knee osteoarthritis (OA) because of lack of high-quality evidence on efficacy for symptoms and joint structure, but the guidelines emphasize the need for rigorous studies. Despite this, use of PRP in knee OA is increasing.

OBJECTIVE

To evaluate the effects of intra-articular PRP injections on symptoms and joint structure in patients with symptomatic mild to moderate radiographic medial knee OA.

DESIGN, SETTING, AND PARTICIPANTS

This randomized, 2-group, placebo-controlled, participant-, injector-, and assessor-blinded clinical trial enrolled community-based participants (n = 288) aged 50 years or older with symptomatic medial knee OA (Kellgren and Lawrence grade 2 or 3) in Sydney and Melbourne, Australia, from August 24, 2017, to July 5, 2019. The 12-month follow-up was completed on July 22, 2020.

INTERVENTIONS

Interventions involved 3 intra-articular injections at weekly intervals of either leukocyte-poor PRP using a commercially available product (n = 144 participants) or saline placebo (n = 144 participants).

MAIN OUTCOMES AND MEASURES

The 2 primary outcomes were 12-month change in overall average knee pain scores (11-point scale; range, 0-10, with higher scores indicating worse pain; minimum clinically important difference of 1.8) and percentage change in medial tibial cartilage volume as assessed by magnetic resonance imaging (MRI). Thirty-one secondary outcomes (25 symptom related and 6 MRI assessed; minimum clinically important difference not known) evaluated pain, function, quality of life, global change, and joint structures at 2-month and/or 12-month follow-up.

RESULTS

Among 288 patients who were randomized (mean age, 61.9 [SD, 6.5] years; 169 [59%] women), 269 (93%) completed the trial. In both groups, 140 participants (97%) received all 3 injections. After 12 months, treatment with PRP vs placebo injection resulted in a mean change in knee pain scores of -2.1 vs -1.8 points, respectively (difference, -0.4 [95% CI, -0.9 to 0.2] points; P = .17). The mean change in medial tibial cartilage volume was -1.4% vs -1.2%, respectively (difference, -0.2% [95% CI, -1.9% to 1.5%]; P = .81). Of 31 prespecified secondary outcomes, 29 showed no significant between-group differences.

CONCLUSIONS AND RELEVANCE

Among patients with symptomatic mild to moderate radiographic knee OA, intra-articular injection of PRP, compared with injection of saline placebo, did not result in a significant difference in symptoms or joint structure at 12 months. These findings do not support use of PRP for the management of knee OA.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry Identifier: ACTRN12617000853347.

Limonin Inhibits IL-1β-Induced Inflammation and Catabolism in Chondrocytes and Ameliorates Osteoarthritis by Activating Nrf2

Osteoarthritis (OA), a degenerative disorder, is considered to be one of the most common forms of arthritis. Limonin (Lim) is extracted from lemons and other citrus fruits. Limonin has been reported to have anti-inflammatory effects, while inflammation is a major cause of OA; thus, we propose that limonin may have a therapeutic effect on OA. In this study, the therapeutic effect of limonin on OA was assessed in chondrocytes in vitro in IL-1β induced OA and in the destabilization of the medial meniscus (DMM) mice in vivo. The Nrf2/HO-1/NF-κB signaling pathway was evaluated to illustrate the working mechanism of limonin on OA in chondrocytes. In this study, it was found that limonin can reduce the level of IL-1β induced proinflammatory cytokines such as INOS, COX-2, PGE2, NO, TNF-α, and IL-6. Limonin can also diminish the biosynthesis of IL-1β-stimulated chondrogenic catabolic enzymes such as MMP13 and ADAMTS5 in chondrocytes. The research on the mechanism study demonstrated that limonin exerts its protective effect on OA through the Nrf2/HO-1/NF-κB signaling pathway. Taken together, the present study shows that limonin may activate the Nrf2/HO-1/NF-κB pathway to alleviate OA, making it a candidate therapeutic agent for OA.

Cell and Cell Free Therapies in Osteoarthritis

Osteoarthritis (OA) is the most common articular disease in adults and has a current prevalence of 12% in the population over 65 years old. This chronic disease causes damage to articular cartilage and synovial joints, causing pain and leading to a negative impact on patients' function, decreasing quality of life. There are many limitations regarding OA conventional therapies-pharmacological therapy can cause gastrointestinal, renal, and cardiac adverse effects, and some of them could even be a threat to life. On the other hand, surgical options, such as microfracture, have been used for the last 20 years, but hyaline cartilage has a limited regeneration capacity. In recent years, the interest in new therapies, such as cell-based and cell-free therapies, has been considerably increasing. The purpose of this review is to describe and compare bioregenerative therapies' efficacy for OA, with particular emphasis on the use of mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP). In OA, these therapies might be an alternative and less invasive treatment than surgery, and a more effective option than conventional therapies.

Photobiomodulation (λ=808nm) and Platelet-Rich Plasma (PRP) for the Treatment of Acute Rheumatoid Arthritis in Wistar Rats

Introduction: Rheumatoid arthritis (RA) causes inflammation, pain, edema, and articular degradation and its treatment can be based on anti-inflammatory drugs, photobiomodulation (PBM) and/or platelet-rich plasma (PRP) that can decrease cell flow and promote local healing. In the present study, we evaluate the effects of PBM and PRP on acute arthritis in Wistar rats through inflammatory and oxidative stress parameters. Methods: Thirty female Wistar rats were assigned to five groups (n=6, each group): Control, Sham, PRP, Laser, and PRP+Laser. For arthritis induction, all animals of groups Sham, PRP, Laser and PRP+Laser received an intraarticular injection of Zymosan® (200µg) in the right knee. Twenty-four hours post-arthritis induction, PRP was prepared and injected (8 × 105 of platelets) in animals of PRP and PRP+Laser groups. PBM was performed in Laser and PRP+Laser groups by single-dose therapy with the GaAlAs laser (λ=808 nm, P=25 mW, fluence=30 J/cm2, beam area=0.02 mm2, t=33 seconds, E=0.825 J, punctual application). After seven days of induction, serum samples were collected and thiobarbituric acid reactive substances (TBARS), nitric oxide (NO) and catalase activity were analysed. Morphological parameters were measured for inflammation areas, cartilage thickness, and C3 protein expression in knee samples. Statistical analysis was performed with an ANOVA test and Tukey's post-hoc test with a significance level of 5% (P<0.05). Results: NO was lower in the treated groups compared to the Sham group, and TBARS did not show any differences, while catalase showed greater activity between PRP+Laser versus PRP (P<0.05). Inflammatory areas and cartilage thickness were lower in the treated groups compared to Sham (P<0.05), while no differences in C3 protein expression was observed. Conclusion: PBM associated with PRP is better for anti-inflammatory and joint preservation by morphological aspects and NO levels that concern a potential clinical application.

Google Trends Analysis Shows Increasing Public Interest in Platelet-Rich Plasma Injections for Hip and Knee Osteoarthritis

BACKGROUND

Osteoarthritis is a chronic musculoskeletal condition that frequently affects the hip and knee joints. Given the burden associated with surgical intervention for hip and knee osteoarthritis, patients continue to search for potential nonoperative treatments. One biologic therapy with mixed clinical and basic science evidence for treating osteoarthritis is platelet-rich plasma injections into the affected joint. We used the Google Trends tool to provide a quantitative analysis of national interest in platelet-rich plasma injections for hip and knee osteoarthritis.

METHODS

Google Trends parameters were selected to obtain search data from January 2009 to December 2019. Various combinations of "arthritis," "osteoarthritis," "PRP," "platelet-rich plasma," "knee," and "hip" were entered into the Google Trends tool and trend analyses were performed.

RESULTS

Three linear models were generated to display search volume trends in the United States for platelet-rich plasma and osteoarthritis, hip osteoarthritis, and knee osteoarthritis, respectively. All models showed increased Google queries as time progressed (P < .001), with R² ranging from 0.837 to 0.940. Seasonal, income-related, and geographic variations in public interest in platelet-rich plasma for osteoarthritis were noted.

CONCLUSION

Our results demonstrate a significant rise in Google queries related to platelet-rich plasma injections for osteoarthritis of the hip and knee since 2009. Surgeons treating hip and knee osteoarthritis patients can expect continued interest in platelet-rich plasma, despite inconclusive clinical and basic science data. Trends in public interest may inform patient counseling, shared decision-making, and directions for future clinical research.

Autologous blood and platelet-rich plasma injection therapy for lateral elbow pain

BACKGROUND

Autologous whole blood or platelet-rich plasma (PRP) injections are commonly used to treat lateral elbow pain (also known as tennis elbow or lateral epicondylitis or epicondylalgia). Based on animal models and observational studies, these injections may modulate tendon injury healing, but randomised controlled trials have reported inconsistent results regarding benefit for people with lateral elbow pain.

OBJECTIVES

To review current evidence on the benefit and safety of autologous whole blood or platelet-rich plasma (PRP) injection for treatment of people with lateral elbow pain.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and Embase for published trials, and Clinicaltrials.gov and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) search portal for ongoing trials, on 18 September 2020.

SELECTION CRITERIA

We included all randomised controlled trials (RCTs) and quasi-RCTs comparing autologous whole blood or PRP injection therapy to another therapy (placebo or active treatment, including non-pharmacological therapies, and comparison between PRP and autologous blood) for lateral elbow pain. The primary comparison was PRP versus placebo. Major outcomes were pain relief (≥ 30% or ≥ 50%), mean pain, mean function, treatment success, quality of life, withdrawal due to adverse events, and adverse events; the primary time point was three months.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 32 studies with 2337 participants; 56% of participants were female, mean age varied between 36 and 53 years, and mean duration of symptoms ranged from 1 to 22 months. Seven trials had three intervention arms. Ten trials compared autologous blood or PRP injection to placebo injection (primary comparison). Fifteen trials compared autologous blood or PRP injection to glucocorticoid injection. Four studies compared autologous blood to PRP. Two trials compared autologous blood or PRP injection plus tennis elbow strap and exercise versus tennis elbow strap and exercise alone. Two trials compared PRP injection to surgery, and one trial compared PRP injection and dry needling to dry needling alone. Other comparisons include autologous blood versus extracorporeal shock wave therapy; PRP versus arthroscopic surgery; PRP versus laser; and autologous blood versus polidocanol. Most studies were at risk of selection, performance, and detection biases, mainly due to inadequate allocation concealment and lack of participant blinding. We found moderate-certainty evidence (downgraded for bias) to show that autologous blood or PRP injection probably does not provide clinically significant improvement in pain or function compared with placebo injection at three months. Further, low-certainty evidence (downgraded for bias and imprecision) suggests that PRP may not increase risk for adverse events. We are uncertain whether autologous blood or PRP injection improves treatment success (downgraded for bias, imprecision, and indirectness) or withdrawals due to adverse events (downgraded for bias and twice for imprecision). No studies measured health-related quality of life, and no studies reported pain relief (> 30% or 50%) at three months. At three months, mean pain was 3.7 points (0 to 10; 0 is best) with placebo and 0.16 points better (95% confidence interval (CI) 0.60 better to 0.29 worse; 8 studies, 523 participants) with autologous blood or PRP injection, for absolute improvement of 1.6% better (6% better to 3% worse). At three months, mean function was 27.5 points (0 to 100; 0 is best) with placebo and 1.86 points better (95% CI 4.9 better to 1.25 worse; 8 studies, 502 participants) with autologous blood or PRP injection, for absolute benefit of 1.9% (5% better to 1% worse), and treatment success was 121 out of 185 (65%) with placebo versus 125 out of 187 (67%) with autologous blood or PRP injection (risk ratio (RR) 1.00; 95% CI 0.83 to 1.19; 4 studies, 372 participants), for absolute improvement of 0% (11.1% lower to 12.4% higher). Regarding harm, we found very low-certainty evidence to suggest that we are uncertain whether withdrawal rates due to adverse events differed. Low-certainty evidence suggests that autologous blood or PRP injection may not increase adverse events compared with placebo injection. Withdrawal due to adverse events occurred in 3 out of 39 (8%) participants treated with placebo versus 1 out of 41 (2%) treated with autologous blood or PRP injection (RR 0.32, 95% CI 0.03 to 2.92; 1 study), for an absolute difference of 5.2% fewer (7.5% fewer to 14.8% more). Adverse event rates were 35 out of 208 (17%) with placebo versus 41 out of 217 (19%) with autologous blood or PRP injection (RR 1.14, 95% CI 0.76 to 1.72; 5 studies; 425 participants), for an absolute difference of 2.4% more (4% fewer to 12% more). At six and twelve months, no clinically important benefit for mean pain or function was observed with autologous blood or PRP injection compared with placebo injection.

AUTHORS' CONCLUSIONS

Data in this review do not support the use of autologous blood or PRP injection for treatment of lateral elbow pain. These injections probably provide little or no clinically important benefit for pain or function (moderate-certainty evidence), and it is uncertain (very low-certainty evidence) whether they improve treatment success and pain relief > 50%, or increase withdrawal due to adverse events. Although risk for harm may not be increased compared with placebo injection (low-certainty evidence), injection therapies cause pain and carry a small risk of infection. With no evidence of benefit, the costs and risks are not justified.

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

Background

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

Methods

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

Results

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

Conclusions

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

Trial registration

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

Supplementary Information

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

Osteoarthritis Progression: Mitigation and Rehabilitation Strategies

Osteoarthritis is the most common form of arthritis and is a substantial burden for patients with the disease. Currently, there is no cure for osteoarthritis, but many emerging therapies have been developed to aid in the mitigation of disease progression. When osteoarthritis reaches the end-stage of disease many patients undergo total joint arthroplasty to improve quality of life, yet some experience persistent pain and mobility limitations for extended periods following surgery. This review highlights recent therapeutic advancements in osteoarthritis treatment consisting of pharmacologics, nutraceuticals, biologics, and exercise while emphasizing the current state of post-arthroplasty rehabilitation.

Extracellular Vesicles as Biological Indicators and Potential Sources of Autologous Therapeutics in Osteoarthritis

Along with cytokines, extracellular vesicles (EVs) released by immune cells in the joint contribute to osteoarthritis (OA) pathogenesis. By high-resolution flow cytometry, we characterized 18 surface markers and 4 proinflammatory cytokines carried by EVs of various sizes in plasma and synovial fluid (SF) from individuals with knee OA, with a primary focus on immune cells that play a major role in OA pathogenesis. By multiplex immunoassay, we also measured concentrations of cytokines within (endo) and outside (exo) EVs. EVs carrying HLA-DR, -DP and -DQ were the most enriched subpopulations in SF relative to plasma (25–50-fold higher depending on size), suggesting a major contribution to the SF EV pool from infiltrating immune cells in OA joints. In contrast, the CD34⁺ medium and small EVs, reflecting hematopoietic stem cells, progenitor cells, and endothelial cells, were the most significantly enriched subpopulations in plasma relative to SF (7.3- and 7.7-fold higher). Ratios of EVs derived from neutrophils and lymphocytes were highly correlated between SF and plasma, indicating that plasma EVs could reflect OA severity and serve as systemic biomarkers of OA joint pathogenesis. Select subsets of plasma EVs might also provide next generation autologous biological products for intra-articular therapy of OA joints.

Frontier review of the roles of exosomes in osteoarthritis

Osteoarthritis (OA) is a common degenerative disease; however, its exact pathophysiology and early diagnosis are still a challenge. Growing attention to the exosomes may inspire innovations that would make the current management of OA more effective. The exosomes in synovial fluid are relatively stable, and they can be easily isolated by the relatively noninvasive procedure of liquid biopsy to provide diagnostic and monitoring value. Some miRNAs (miR-504, miR-146a, miR-26a, miR-200c, and miR-210) have been known to be secreted in exosomes of OA patients. On the other hand, intraarticular injection of platelet-rich plasma (PRP) is becoming a popular therapy for OA patients. PRP is also a source of exosomes and their numerous contents. It is evident from the literature that PRP-derived exosomes can induce chondrogenic gene expression in OA chondrocytes. Here, we review the latest findings on the roles of exosomes in OA with the emphasis on PRP-derived exosomes and their potential applications for treating OA.

Hip Instability in Ballet Dancers: A Narrative Review

BACKGROUND

Dancers possess a large degree of hip range of motion that results from a combination of innate and acquired osseous morphology and permissive soft tissues. Generalized hypermobility in dancers may predispose them to a spectrum of hip instability. The objective of this narrative review is to discuss the anatomical characteristics, pathogenesis, risk factors, clinical signs and symptoms, management, and outcomes of hip instability treatments in dancers.

METHODS

A retrospective search was performed beginning November 1, 2017, for English language articles regarding hip stability in the dancer. Key words used included but were not limited to: dance(r), ballet, hip, hypermobility, range of motion, instability, microinstability, and laxity. PubMed, Scopus, and MEDLINE databases were used.

RESULTS

Forty-three studies were analyzed. Groin pain was found to be the most common presenting symptom of hip instability. A variety of impingement and instability signs may be elicited during physical examination. Hypermobility is frequently observed and is thought to be a necessity for participation in elite levels of ballet. Radiographs and advanced planar imaging (magnetic resonance imaging and computed tomography) should be scrutinized to evaluate for dysplasia, cam, pincer, subspine, and rotational morphologies. Dysplasia (low volume acetabulum), cam morphology, femoral retroversion, and coxa valga are common findings in the ballet dancers' hip. Labral injuries and ligamentum teres tears are common and may potentiate instability in the hip. Management options include education, oral non-opioid medications, activity modification, exercise prescription, and surgery. Reported outcomes of these treatments in ballet are limited.

CONCLUSION

Hip hypermobility is prevalent in the ballet population and is a clear advantage. However, it may increase the risk of instability. It is important to identify the multifactorial osseous and soft tissue etiology of hip or groin pain in dancers. Practitioners should have a high level of suspicion for hip instability in the dancer presenting with hip pain and treat accordingly. There is a significant need for increased quantity and quality of investigation into the outcomes of treatment for hip instability in the dancer.

Efficacy of different platelet-rich plasma injections in the treatment of mild-moderate knee osteoarthritis: A systematic review and meta-analysis

AIMS

This study aimed to compare the efficacy of different numbered sets of injections of platelet-rich plasma (PRP) in the treatment of mild-moderate knee osteoarthritis (OA).

METHODS

A comprehensive search in three databases of Cochrane Library, Embase, and PubMed was conducted to find relevant articles that investigated the efficacy of PRP injection therapies in the treatment of mild-moderate knee OA through August 2020. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain and function scores were the primary outcomes and visual analogue scale (VAS) was the secondary outcome. The pooled improvements amongst different injection therapies were compared.

RESULTS

No significant differences in the improvement of WOMAC pain were observed amongst 1-, 2-, and 3-injection therapies at 3- (P = .26) and 6-month (P = .13) follow-ups. For a 12-month follow-up, the difference amongst different therapies reached borderline significance (P = .05) in which 3-injection therapy had a significantly better improvement than 2-injection therapy (P = .02) and reached borderline significance compared with 1-injection (P = .07). However, no significant differences in the improvement of VAS scores were observed amongst three injection therapies for all the follow-up visits (P > .05). For WOMAC function score, 3-injection therapy performed significantly better than 1-injection (P < .00001) or 2-injection therapy (P < .0001) only at 12-month follow-up visit.

CONCLUSIONS

Our results demonstrated that 3-injection therapy of PRP in the treatment of mild-moderate knee OA had the best efficacy in pain relief and function improvement compared with 1- and 2-injection therapies.

Autologous platelet-rich plasma repairs burn wound and reduces burn pain in rats

OBJECTIVE

To investigate the effects of autologous platelet-rich plasma (PRP) on burn wound and burn pain in rats.

METHODS

Rats were treated with high-temperature copper rod to induce skin burn. During treatment, the wound area of rats was recorded on days 0, 3, 7, 10, 14 and healing rates were calculated. After 14-day treatment, the paw withdrawal mechanical threshold (PWMT) as well as paw withdrawal thermal latency (PWTL) were measured. In addition, CD31 expression in burn wound was detected by Immunohistochemistry. The contents of TNF-α and IL-1β in wound tissues were detected by ELISA. Moreover, the mRNA and protein expression levels of VEGF, MMP-9 and TGF-β1 in wound tissues were detected by RT-qPCR together with Western blot.

RESULTS

Burn wound of rats in the PRP group gradually got better with a decreased wound area. Compared with the NS group, the wound area of the PRP group was significantly reduced and the healing rate was significantly increased. Meanwhile, PWMT of the rats in the PRP group was obviously increased compared with the NS group. Compared with the NS group, the rate of CD31-positive cells in the wound tissue of burned rats was increased; while the contents of TNF-α and IL-1β were significantly decreased after a subcutaneous injection of PRP. In addition, the mRNA and protein expression levels of VEGF, MMP-9 and TGF-β1 in the wound tissue of rats from PRP group were evidently increased.

CONCLUSION

Autologous platelet-rich plasma not only shortened the healing time, but also relieved the burn pain.

Orthobiologics in the treatment of hip disorders

Orthobiologics are biological materials that are intended for the regeneration or healing of bone, cartilage and soft tissues. In this review we discuss the use of orthobiologics for hip disorders providing an update. The orthobiologics included in this article are hyaluronic acid, platelet rich plasma, bone marrow, adipose tissue and expanded mesenchymal stem cells. We explain the concepts and definitions of each orthobiological product, and the literature regarding its use in the hip joint. The paucity of guidelines for the production and characterization of the biological products leads to uneven results across the literature. Each biologic therapy has indications and benefits; however, noteworthy are the characterization of the orthobiologics, the application method and outcome analysis for further improvement of each technique.

From Pathogenesis to Therapy in Knee Osteoarthritis: Bench-to-Bedside

Osteoarthritis (OA) is currently the most widespread musculoskeletal condition and primarily affects weight-bearing joints such as the knees and hips. Importantly, knee OA remains a multifactorial whole-joint disease, the appearance and progression of which involves the alteration of articular cartilage as well as the synovium, subchondral bone, ligaments, and muscles through intricate pathomechanisms. Whereas it was initially depicted as a predominantly aging-related and mechanically driven condition given its clear association with old age, high body mass index (BMI), and joint malalignment, more recent research identified and described a plethora of further factors contributing to knee OA pathogenesis. However, the pathogenic intricacies between the molecular pathways involved in OA prompted the study of certain drugs for more than one therapeutic target (amelioration of cartilage and bone changes, and synovial inflammation). Most clinical studies regarding knee OA focus mainly on improvement in pain and joint function and thus do not provide sufficient evidence on the possible disease-modifying properties of the tested drugs. Currently, there is an unmet need for further research regarding OA pathogenesis as well as the introduction and exhaustive testing of potential disease-modifying pharmacotherapies in order to structure an effective treatment plan for these patients.

Platelet-rich plasma vs bone marrow aspirate concentrate: An overview of mechanisms of action and orthobiologic synergistic effects

The use of orthobiologics as a novel therapy for the treatment of numerous musculoskeletal disorders has increased considerably over the past decade. Currently, there are multiple alternatives available as suitable treatments; however, the use of autologous blood-derived products such as platelet-rich plasma (PRP), bone marrow aspirate (BMA) and BMA concentrate (BMAC), specifically, is expanding. Although many investigations attempted to demonstrate the effectiveness of these therapies, even with positive results, the literature lacks standardized protocols and overall accuracy in study designs, which leads to variance and difficulty in reproducibility of protocols. The efficacy of PRP for the treatment of cartilage, bone and muscle tissues is well known. Although BMAC has generated optimistic results for the same purposes, its applicability in clinical trials is still relatively recent when compared to PRP. Both products demonstrate the potential to set forth reparative processes, each in their own distinct mechanism. The combination of these biological products has been previously proposed, yet little is known about their synergism. Evidence indicates that growth factor, cytokine, and chemokine profiles seen in both PRP and BMAC vary but are likely to work synergistically to enhance musculoskeletal healing. BMAC products seem to work well without PRP; however, the addition of PRP to BMAC has been shown to act as a rich and natural source of culture medium for stem cells located either peripherally or in the bone marrow itself. Nevertheless, additional variables associated with the use of BMAC and PRP in orthopedics must be further evaluated in order to consolidate the efficacy of this therapeutic strategy.

Non-surgical osteoarthritis therapy, intra-articular drug delivery towards clinical applications

Osteoarthritis (OA）is a common orthopaedic disease in middle-aged and aged people. To date, no disease-modifying drug is available to prevent the progression of OA. Surgical treatment of OA has complications such as pain and high costs with increased risk of post-operative infections. An intra-articular drug delivery is a conservative treatment method to apply therapeutic composites directly into the OA joint cavity. This method has an advantage to improve the bioavailability of therapeutics and hence is a widely preferred choice to test novel disease-modifying drug targets for OA. Herein, we summarised and discussed the current status of intra-articular therapy for OA treatment as well as outlined drug delivery of small molecular, protein and gene delivery for OA therapy. Currently, new targeted nano-based drug delivery systems, including nanoparticles, exosomes and hydrogel formulations under investigation for OA treatment via intra-articular injection are also addressed. The emerging trend demonstrates that intra-articular drug delivery has vast prospects for the clinical selective treatment of OA. The rational application of intra-articular injection of drugs and biological agents will be of great significance for alleviating the patients with OA, improving their quality of life, delaying surgery, and reducing the disease burden of OA.

Intra-Articular Injections in Knee Osteoarthritis: A Review of Literature

Knee osteoarthritis (OA) is a chronic, degenerative, and progressive disease of articular cartilage, producing discomfort and physical disability in older adults. Thirteen percent of elderly people complain of knee OA. Management options for knee OA could be divided into the following categories: conservative, pharmacological, procedural, and surgical. Joint replacement is the gold standard, reserved for severe grades of knee OA, due to its complications rate and increased risk of joint revision. A nonsurgical approach is the first choice in the adult population with cartilage damage and knee OA. Yearly, more than 10% of knee OA-affected patients undergo intra-articular injections of different drugs, especially within three months after OA diagnosis. Several molecules, such as corticosteroids injection, hyaluronic acid (HA), and platelet-rich plasma (PRP), are managed to reduce the symptoms of patients with knee OA. The aim of this review was to offer an overview of intra-articular injections used for the treatment of OA and report the conventional pharmacological products used.

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.

Effectiveness of Traditional Chinese Exercise for Symptoms of Knee Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background: Growing evidences have advocated the potential benefits of traditional Chinese exercise (TCE) on symptomatic improvement of knee osteoarthritis (KOA). However, most of them have been derived from cross-sectional studies or case reports; the effectiveness of TCE therapies has not been fully assessed with a randomized control trial (RCT). In order to evaluate the combined clinical effectiveness of TCE for KOA, we conducted a systematic review and meta-analysis on the existing RCTs on KOA. Methods: A systematic search was performed in four electronic databases: PubMed, Web of Science, Cochrane Library, and EMBASE from the time of their inception to February 2020. All eligible RCTs were included in which TCE was utilized for treating KOA as compared to a control group. Two reviewers independently extracted the data and evaluated the risk of bias following the Cochrane Risk of Bias Tool for RCT. The symptoms of KOA evaluated by the Western Ontario and McMaster Universities Arthritis Index (WOMAC) and the Knee Injury and Osteoarthritis Outcome Score (KOOS) were regarded as the primary outcomes in this study. Each outcome measure was pooled by a standardized mean difference (SMD) with 95% confidence intervals (CI). A meta-analysis was applied with a random or fixed effect model for the collected data to calculate the summary SMD with 95% CI based on different statistical heterogeneity. In addition, subgroup analyses were used to investigate heterogeneity and sensitivity analysis was carried out for the results of the meta-analysis. Egger’s test and the funnel plots were used to examine the potential bias in the RCTs. Results: A total of 14 RCTs involving 815 patients with KOA were included. Compared with a control group; the synthesized data of TCE showed a significant improvement in WOMAC/KOOS pain score (SMD = −0.61; 95% CI: −0.86 to −0.37; p < 0.001), stiffness score (SMD = −0.75; 95% CI: −1.09 to −0.41; p < 0.001), and physical function score (SMD = −0.67; 95% CI: −0.82 to −0.53; p < 0.001). Conclusions: Our meta-analysis suggested that TCE may be effective in alleviating pain; relieving stiffness and improving the physical function for patients with KOA. Yet; given the methodological limitations of included RCTs in this meta-analysis; more high-quality RCTs with large sample size and long-term intervention are required to further confirm the effectiveness and underlying mechanisms of TCE for treating KOA.

MiR-193b modulates osteoarthritis progression through targeting ST3GAL4 via sialylation of CD44 and NF-кB pathway

Osteoarthritis (OA) is a worldwide epidemic and debilitating disease. It is urgent to explore the potential molecular mechanisms of OA which has crucial roles in the treatment strategy. As a post-translational modification, sialylation mediates the progression of OA. In current study, differential expression of sialyltransferases (STs) in normal and OA cartilage tissues is detected. The ST3GAL4 expression is significantly increased and positively associated with modified Mankin's score in OA tissue. Alteration of ST3GAL4 respectively mediates the degradation of extracellular mechanisms (ECM), apoptosis and proliferation in chondrocytes. Additionally, miR-193b is identified as a direct regulatory target of ST3GAL4. Functional analysis shows that modulation of ST3GAL4 could be reversed by miR-193b. Over-expression ST3GAL4 modifies CD44 sialylation. Finally, sialylated CD44 reduces the binding capacity to lubricin and mediates the activity of the NF-кB pathway. Collectively, these researches indicate that miR-193b/ST3GAL4 axis impacts OA progression by regulating CD44 sialylation via NF-кB pathway. Our researches propose a precise molecular mechanism and provide a prospective therapeutic target in OA.

Leukocyte-dependent effects of platelet-rich plasma on cartilage loss and thermal hyperalgesia in a mouse model of post-traumatic osteoarthritis

OBJECTIVE

Platelet-rich plasma (PRP) is an emerging therapeutic strategy for treatment of osteoarthritis (OA); however, there is a lack of preclinical and clinical evidence for its efficacy and its mechanism of action is unclear. In the current study, we utilized leukocyte poor-PRP (LP-PRP) and leukocyte rich-PRP (LR-PRP) to mimic clinical point of care formulations and assessed their potential to alter disease progression in a mouse model of post-traumatic OA.

METHOD

Three-month-old wild-type male FVB/N mice received destabilization of the medial meniscus (DMM) surgery to induce OA. To assess the efficacy of LP-PRP and LR-PRP, mice were given intraarticular injections at 2-, 7- and 28-days post-surgery. Mice were then assessed at 5-, 9-, and 13-weeks post-surgery for changes in chronic pain using the hot plate nociceptive assay. At 14-weeks, OA pathogenesis was evaluated using histology and phase-contrast μCT.

RESULTS

Treatment with LP-PRP and to a lesser extent LR-PRP preserved cartilage volume and surface area compared to phosphate-buffered saline (PBS) as measured by phase-contrast μCT. However, both treatments had higher Osteoarthritis Research Society International (OARSI) and synovitis scores compared to sham, and neither substantially improved scores compared to PBS controls. With respect to thermal hyperalgesia, PBS-treated mice displayed reduced latency to response compared to sham, and LR-PRP but not LP-PRP improved latency to response at 5-, 9- and 13-weeks post-surgery compared to PBS.

CONCLUSION

The results of this study suggest that effects of PRP therapy on OA progression and disease-induced hyperalgesia may be leukocyte-dependent. And while LP-PRP and to a lesser extent LR-PRP protect from volume and surface loss, significant pathology is still seen within OA joints. Future work is needed to understand how the different components of PRP effect OA pathogenesis and pain, and how these could be modified to achieve greater therapeutic efficacy.

The Role of HDACs and HDACi in Cartilage and Osteoarthritis

Epigenetics plays an important role in the pathogenesis and treatment of osteoarthritis (OA). In recent decades, HDAC family members have been associated with OA. This paper aims to describe the different role of HDACs in the pathogenesis of OA through interaction with microRNAs and the regulation of relevant signaling pathways. We found that HDACs are involved in cartilage and chondrocyte development but also play a crucial role in OA. However, the distinct HDAC mechanism in the pathogenesis and treatment of OA require further investigation. Furthermore, HDAC inhibitors (HDACi) can protect cartilage from disease, which may represent a potential therapeutic approach against OA.

Autologous Protein Solution Injections for the Treatment of Knee Osteoarthritis: 3-Year Results

BACKGROUND

Blood derivative injections have been recently proposed to address osteoarthritis (OA) with overall positive results, although long-term data on their efficacy are lacking. A novel blood derivative has been developed to concentrate growth factors and antagonists of inflammatory cytokines and shown promising early findings.

PURPOSE

To investigate if the positive effects of a single intra-articular injection of autologous protein solution (APS) in patients affected by knee OA-previously documented at 1 year in a multicenter double-blind randomized saline-controlled trial-last up to 3 years.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 46 patients with Kellgren-Lawrence 2 or 3 knee OA were randomized into 2 groups: 1 ultrasound-guided APS injection (n = 31) or 1 saline injection (n = 15). At 1 year, the saline group was allowed to cross over. Patients were re-evaluated at 24 and 36 months through the visual analog scale for pain (VAS), Western Ontario and McMaster Universities Osteoarthritis Index Likert 3.1 (WOMAC LK 3.1), Knee injury and Osteoarthritis Outcome Score (KOOS), 36-Item Short Form Health Survey (SF-36), and Outcome Measures in Rheumatology-Osteoarthritis Research Society International (OMERACT-OARSI) responder rate. Magnetic resonance imaging evaluation was performed with the MRI Osteoarthritis Knee Score (MOAKS) before and at 24 months after treatment, and radiographs were assessed per Kellgren-Lawrence before and annually after treatment.

RESULTS

In the APS cohort, WOMAC pain improved from 11.5 ± 2.4 (mean ± SD) to 4.3 ± 4.0 at 1 year and to 5.7 ± 5.0 at 3 years (P < .0001 vs baseline). The APS cohort also showed a statistically significant improvement in its KOOS pain score from 39.4 ± 13.1 to 70.6 ± 21.5 at 1 year and to 64.1 ± 24.6 at 3 years (P < .0001 vs baseline) and VAS pain scores from 5.5 ± 2.2 to 2.6 ± 2.5 at 1 year and to 3.4 ± 2.9 at 3 years (P = .0184 vs baseline). VAS pain score significantly worsened from 12 to 36 months (P = .0411). All patients in the saline group decided to cross over to APS, and their final scores were better than baseline, although not significantly better than at the crossover point. Overall, 7 of 26 (26.9%) APS cases and 4 of 14 (28.6%) crossover cases were considered failures as patients underwent further injective treatments or surgical procedures between the 12- and 36-month follow-up. MOAKS findings showed no statistically significant differences. Patients with better cartilage had greater WOMAC pain improvement when their baseline scores were worse, whereas the trend was reversed for patients with cartilage loss at baseline.

CONCLUSION

Intra-articular use of APS for mild to moderate knee OA was safe, and significant pain improvement was documented 3 years after a single injection. Patients with better cartilage status seem to respond better than patients with more cartilage loss, with more clinical improvement even when starting from more painful conditions.

REGISTRATION

NCT02138890 (ClinicalTrials.gov identifier).

Intra-articular saline injection is as effective as corticosteroids, platelet-rich plasma and hyaluronic acid for hip osteoarthritis pain: a systematic review and network meta-analysis of randomised controlled trials

Objective

Intra-articular (IA) injections represent a commonly used modality in the treatment of hip osteoarthritis (OA). Commonly used injections include corticosteroids (CCS), hyaluronic acid (HA) and platelet-rich plasma (PRP). A network meta-analysis allows for comparison among more than two treatment arms and uses both direct and indirect comparisons between interventions. The objective of this network meta-analysis is to compare the efficacy of the various IA injectable treatments in treating hip OA at up to 6 months of follow-up.

Design

This is a systematic review and network meta-analysis. Bayesian random-effects model was performed to assess the direct and indirect comparisons of all treatment options.

Data sources

PubMed, Embase, Cochrane Central Register of Controlled Trials, Scopus and Web of Science, from inception to October 2019.

Eligibility criteria for selected studies

Randomised controlled trials assessing the efficacy of CCS, HA, PRP and placebo in the form of IA saline injection for patients with hip OA.

Results

Eleven randomised controlled trials comprising 1353 patients were included. For pain outcomes at both 2–4 and 6 months, no intervention significantly outperformed placebo IA injection. For functional outcomes at both 2–4 and 6 months, no intervention significantly outperformed placebo IA injection. Regarding change from baseline at 2–4 months and 6 months, pooled data demonstrated that all interventions (including placebo), with the exception of HA+PRP, led to a clinically important improvement in both pain, exceeding the minimal clinically important difference.

Conclusion

Evidence suggests that IA hip saline injections performed as well as all other injectable options in the management of hip pain and functional outcomes.

The efficiency of platelet-rich plasma treatment in patients with knee osteoarthritis

OBJECTIVE

The aim of this study was to determine the effects of platelet-rich plasma (PRP) treatment on pain, functionality, quality of life, and cartilage thickness in patients with knee osteoarthritis (OA).

METHODS

Sixty patients with chronic knee pain were randomly separated into two groups. The first group was administered 4-ml PRP intra-articularly (IA) in three doses at one-week intervals, and the second group had only one dose of a 4-ml saline solution IA. The patients' pain was measured using the Visual Analogue Scale (VAS); functionality was measured using the Western Ontario and McMaster University Osteoarthritis Index (WOMAC). The distal femur cartilage thickness was assessed using ultrasonography (USG).

RESULTS

All baseline parameters were similar (p> 0.05). In the first and sixth months after the treatment, the VAS scores of the PRP group were significantly low (p< 0.001). In the same group, only the pain sub-score was low in the WOMAC assessment in the first month after treatment. However, in the sixth month, all parameters of the WOMAC score were lower than those of the placebo group (p< 0.05). Cartilage thickness measurements were similar in the two groups (p< 0.05).

CONCLUSION

PRP treatment had positive effects on the pain, physical function, and quality of life of patients with knee OA, but it did not increase cartilage thickness.

Patient-Reported Outcomes After Platelet-Rich Plasma, Bone Marrow Aspirate, and Adipose-Derived Mesenchymal Stem Cell Injections for Symptomatic Knee Osteoarthritis

Objective:

The objective of this study was to compare platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and adipose-derived mesenchymal stem cell (MSC) injections in the treatment of osteoarthritis (OA) of the knee using functional scores.

Methods:

A total of 89 patients with painful knee OA were included in this study. Patients were assigned to one of the 3 treatments according to severity of OA as indicated by symptoms and radiography to PRP (stage I), BMAC (stage II), or adipose-derived MSC (stage III). Clinical assessment was performed using the Knee Society Score, which combines the Knee Score, based on the clinical parameters, and the Functional Score, and IKDC score. Surveys were completed at preoperative and at 90, 180, and 265 days postoperative. The follow-up responses were compared with baseline and between treatment groups.

Results:

Treatment with PRP, BMAC, and adipose-derived MSC included 29 (32.6%), 27 (30.3%), and 33 (37.1%) patients, respectively. For the total group, median age was 61 years (range: 22-84 years). Score values were comparable among treatment groups at baseline. Statistically significant improvement was observed in the 3 groups according to the 3 scores at all time points during follow-up compared with baseline. No difference was found among treatment type.

Conclusions:

Our findings support previous reports and encourage further research on the use of these cost-effective treatments for OA of the knee.

Intraosseous infiltrations of Platelet-Rich Plasma for severe hip osteoarthritis: A pilot study

OBJECTIVE

Addressing the subchondral bone through intraosseous infiltrations of Platelet-Rich Plasma (PRP) may improve the effectiveness of this technique for severe hip osteoarthritis (HOA).

METHODS

Forty patients with HOA degree 2 and 3 according to the Tönnis scale were recruited for this study. They were susceptible to a total hip arthroplasty, without response to previous treatment based on intraarticular infiltrations of PRP. Patients received a combination of intraosseous injections into the acetabulum and the femoral head, as well as intraarticular PRP infiltrations. The clinical outcome was evaluated at 2, 6 and 12 months using the Hip Osteoarthritis Outcome Score (HOOS) and the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index.

RESULTS

At 2, 6 and 12 months, patients had significant pain improvement according to HOOS pain, WOMAC pain, and VAS scores. After the treatment, the percentage of patients with minimal clinically important improvement was 40% (16 over 40 patients) at 2 months, 37.5% (15 over 40) at 6 months, and 40% (16 over 40) at 12 months. Conclusion: The combination of intra-articular and intra-osseous infiltrations of PRP showed a pain reduction and improvement in hip joint functionality up to 12 months in patients with severe HOA, with no severe adverse effects.

Intra-articular Injection of Pure Platelet-Rich Plasma Is the Most Effective Treatment for Joint Pain by Modulating Synovial Inflammation and Calcitonin Gene-Related Peptide Expression in a Rat Arthritis Model

BACKGROUND

Platelet-rich plasma (PRP) has emerged as a treatment for osteoarthritis (OA). However, the effect that leukocyte concentrations in PRP have on OA remains unclear.

PURPOSE

To clarify the optimal PRP formulation for OA treatment by comparing pure PRP, leukocyte-poor PRP (LP-PRP), and leukocyte-rich PRP (LR-PRP) in a rat arthritis model.

STUDY DESIGN

Controlled laboratory study.

METHODS

Knee arthritis was induced bilaterally in male Wistar rats with intra-articular injections of monosodium iodoacetate (MIA) on day 0. Rats were randomly assigned to 1 of 3 treatment groups (pure PRP, LP-PRP, and LR-PRP). On day 1, allogenic PRP was injected into the right knee of rats and phosphate-buffered saline was injected into the left knee as a control. Weight distribution on the hindlimbs was measured for 14 days to assess pain behavior. Rats were euthanized at day 5 or 14 for histological assessment of synovial tissue and cartilage. Immunohistochemical staining of calcitonin gene-related peptide (CGRP) and α-smooth muscle actin was performed to determine the mechanism of pain relief induced by the PRP preparations.

RESULTS

In all groups, PRP increased the load-sharing ratio on PRP-injected knees, with pure PRP eliciting the largest effect among the 3 kinds of PRP (P < .05). Structural changes in the synovial tissue were significantly inhibited in the pure-PRP group compared with the control group after both 5 and 14 days (P < .001 and P = .025, respectively), whereas no significant difference was found between the control, LP-PRP, and LR-PRP groups. An inhibitory effect on cartilage degeneration was observed only in the pure-PRP group on day 14. Pure PRP also significantly inhibited expression of CGRP-positive nerve fibers in the infrapatellar fat pad compared with the other groups (P < .05).

CONCLUSION

In an MIA-induced arthritis model, pure PRP injection was the most effective treatment for reduction of pain-related behavior and inhibition of synovial inflammation and pain sensitization.

CLINICAL RELEVANCE

PRP formulations should be optimized for each specific disease. This study shows the superiority of pure PRP for treatment of arthritis and joint pain.

Effectiveness of platelet-rich plasma in the management of hip osteoarthritis: a systematic review and meta-analysis

The effectiveness of platelet-rich plasma (PRP) injections for osteoarthritis (OA) is still controversial. Previous research supports the use of intra-articular PRP injections to promote a favorable environment for joint tissue healing and to delay the progression of OA. The purpose of this review is to investigate the effectiveness of PRP in the management of hip osteoarthritis (HOA). Five electronic databases were searched from inception to May 2019: Medline (via PubMed), SportDiscus via EBSCO, ProQuest Health & Medical Complete, CINAHL, and Cochrane. Risk of bias was assessed with the Cochrane risk of bias tool. The GRADE method was used to assess the level of evidence for the studies included in this review. Clinical trials evaluate PRP injections among adult patients diagnosed with HOA according to the American College of Rheumatology criteria. At least one outcome measure for pain or function must have been reported. A total of 4 trials (334 participants, 340 hips) were included, all marked as "moderate risk of bias". Pain and function were assessed throughout the studies with visual analogue scale (VAS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), and Harris Hip Score (HHS) tools. Intra-articular PRP injections were more effective at stages earlier than 3 months for both treatment groups with the exception of WOMAC score in one study. The superiority of PRP against comparative treatments was only reported in one study; longer-term evaluations from 4 to 12 months showed diverse results, with only one study reporting significantly better results for PRP. PRP may be beneficial and safe for patients with HOA at mid-term follow-up. However, its superiority over other procedures such as hyaluronic acid remains unclear. Further researches with high-quality designs and larger samples become imperative.

Augmentation of Meniscal Repair With Platelet-Rich Plasma: A Systematic Review of Comparative Studies

Background:

The effect of platelet-rich plasma (PRP) augmentation for meniscal repair (MR) is unclear, as current evidence is limited to small, mostly nonrandomized studies.

Purpose:

To systematically review the literature to evaluate the efficacy and safety of MR with PRP augmentation.

Study Design:

Systematic review; Level of evidence, 3.

Methods:

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify studies (level of evidence 1-3) that compared the clinical efficacy of MR performed with versus without PRP. The search phrase used was platelet-rich plasma meniscus. Patients were assessed based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the visual analog scale (VAS) for pain, the Lysholm score, the Knee injury and Osteoarthritis Outcome Score (KOOS), the subjective International Knee Documentation Committee (IKDC) score, and treatment failure.

Results:

We identified 6 studies (2 studies with level 1 evidence; 4 studies with level 3 evidence) that met inclusion criteria, for a total of 309 patients undergoing MR with PRP (mean age, 31.9 years) and 445 patients without PRP augmentation (mean age, 29.6 years). The mean follow-up was 32.8 months (range, 12-72 months). Overall, 17.0% of PRP patients experienced MR failure compared with 22.1% of non-PRP patients. No differences in VAS, Lysholm, or subjective IKDC scores were found between groups except in 1 study, in which postoperative subjective IKDC scores were significantly better in the PRP group (P < .01). Another study found significantly better postoperative WOMAC scores among PRP patients, and 2 studies found significantly better KOOS subscores among PRP patients.

Conclusion:

There are a limited number of high-quality studies comparing outcomes and healing rates between patients undergoing MR with versus without PRP augmentation. Based on the available evidence, patients undergoing MR with PRP augmentation experience similar clinical outcomes at midterm follow-up when compared with conventional MR, and additional studies are needed to determine the efficacy of MR augmented with PRP.

The effects of platelet-rich plasma injection in knee and hip osteoarthritis: a meta-analysis of randomized controlled trials

OBJECTIVE

We conducted this updated meta-analysis to evaluate the effects of PRP in patients with knee or hip OA.

METHOD

PubMed, Embase, and Web of Science were searched to identify randomized controlled trials (RCTs) that compared the efficacy of PRP with other intra-articular injections. The outcomes of interest included Western Ontario and McMaster (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS), Visual Analog Scale (VAS), Harris Hip Score (HHS), and International Knee Documentation Committee (IKDC).

RESULTS

Twenty-four RCTs with 21 at knee OA and three at hip OA were included in this meta-analysis. The PRP injections significantly improved the WOMAC score, VAS score, IKDC score, and HHS score as compared with comparators. The WOMAC pain, stiffness, and physical function scores were also significantly better in the PRP group than in the control group. Most of the evaluated parameters that favored PRP were observed in knee OA but not in hip OA, at short-term (at 1, 2, 3, 6, 12 months) but not long-term follow-up (at 18 months), in RCTs with low risk of bias.

CONCLUSIONS

Intra-articular PRP injection provided better effects than other injections for OA patients, especially in knee OA patients, in terms of pain reduction and function improvement at short-term follow-up. Key Points • This updated meta-analysis, based on great sample size and high-quality studies, evaluates the effects of PRP in patients with knee or hip OA. • Intra-articular PRP injection provided better effects than other injections for OA patients. • Most of the evaluated parameters that favored PRP were observed in knee OA at short term (at 1, 2, 3, 6, 12 months).