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

Randomized Controlled Trials Studying Nonoperative Treatments of Osteoarthritis Often Use Misleading and Uninformative Control Groups: A Systematic Review

BACKGROUND

Because there are no known treatments that alter the natural course of the pathophysiology of osteoarthritis, nonoperative treatment needs to be compared with known effective treatments that seek to mitigate symptoms or with similarly invasive inert (placebo) treatments to determine effectiveness. Comparing a treatment to an uninformative control group may inappropriately legitimize and support the use of potentially ineffective treatments. We therefore investigated the prevalence of inappropriate control groups in musculoskeletal research and asked whether these are associated with reporting a positive treatment effect.

QUESTIONS/PURPOSES

We systematically reviewed randomized trials of nonoperative treatments of osteoarthritis and asked: (1) What proportion of randomized trials use uninformative control groups (defined as a treatment less invasive than the tested treatment, or a treatment that might possibly not outperform placebo but is not acknowledged as such)? (2) Is the use of uninformative control groups independently associated with reporting a positive treatment effect (defined as p < 0.05 in favor of the intervention, or as making a recommendation favoring the intervention over the control treatment)?

METHODS

In a systematic review following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched PubMed, Cochrane, and Embase up to September 2023 for randomized controlled trials published between 2020 to 2022 that compared one or more nonoperative treatments for the symptoms of osteoarthritis. We excluded studies that contained a surgical treatment group. We identified 103 trials that met eligibility criteria, with a total of 15,491 patients. The risk of bias was high in 60% (n = 62) of trials using the Cochrane Risk of Bias Tool, version 2. Although the high risk of bias in the included studies is concerning, it does not invalidate our design; instead, it highlights that some studies may use flawed methods to recommend treatments with unproven effectiveness beyond nonspecific effects because the kinds of bias observed would tend to increase the apparent benefit of the treatment(s) being evaluated. We used logistic regression to test the association of uninformative control groups with a positive treatment effect, accounting for potential confounders such as conflict of interest and study bias using the Cochrane Risk of Bias score.

RESULTS

The use of uninformative control groups (treatments less invasive than the tested treatment, or treatments that might not outperform placebo but are not acknowledged as such) was found in 46% (47 of 103) of included studies. After accounting for potential confounding, there was no association between reporting positive treatment effects and the use of an uninformative control group. Studies with a low risk of bias had a lower likelihood of reporting a positive treatment effect (OR 0.2 [95% confidence interval 0.05 to 0.9]; p = 0.04, model pseudo R 2 = 0.21).

CONCLUSION

The finding that recent studies that mimic high-level evidence often use uninformative control groups that do not adequately account for nonspecific effects (perceived treatment benefits unrelated to a treatment's direct physiological effects) points to a high risk of legitimizing ineffective treatments. This raises the ethical imperative for patients, clinicians, journal peer reviewers, and journal editors to hold researchers to the standard of an adequate, informative control group. Awareness and risk of bias checklists might help patients and clinicians forgo new treatments based on seemingly high-level evidence that may carry only iatrogenic, financial, and psychological harm (false hope, in particular).

LEVEL OF EVIDENCE

Level I, therapeutic study.

Sodium hyaluronate and acupotomy bone decompression alleviates inflammatory responses in patients with knee osteoarthritis

OBJECTIVE

Knee osteoarthritis (KOA), predominantly affecting middle-aged and elderly populations, induces localized joint pain and functional impairment. It was to evaluate the effectiveness of acupotomy bone decompression (ABD) combined with sodium hyaluronate (SH) intra-articular injection on inflammatory responses in treating KOA.

METHODS

Clinical data from 128 patients with KOA were retrospectively collected, categorized into SH group (n = 55) and ABD + SH group (n = 73). Pain was assessed using the visual analogue scale (VAS), knee joint function was evaluated, and knee joint balance and gait parameters were measured. The status of articular cartilage and bone marrow edema was evaluated using quantitative magnetic resonance imaging (MRI). Interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, matrix metalloproteinase (MMP)-3, MMP-9, and hypersensitive C-reactive protein (hs-CRP) were detected.

RESULTS

ABD + SH group showed drastic reductions in VAS scores, decreased indices of different axial balances, and increased stride length and walking speed versus the SH group (P < 0.05). Quantitative MRI examination revealed that relative to the SH group, ABD + SH group exhibited increased thickness of articular cartilage and reduced area of bone marrow edema post-treatment (P < 0.05). Post-treatment levels of hs-CRP, IL-6, IL-1β, TNF-α, MMP-3, and MMP-9 were markedly lower in the ABD + SH group versus SH group (P < 0.05). Moreover, the clinical effective rate in the ABD + SH group was drastically superior to the SH group (95.9% vs. 78.2%, P < 0.05).

CONCLUSION

Combining ABD with SH treatment for KOA effectively alleviates patient pain and inflammatory responses.

Systematic Review of Randomized Controlled Trials Evaluating the Use of Platelet-Rich Plasma for Knee Osteoarthritis: Adherence to Minimum Information for Studies Evaluating Biologics in Orthopaedics

BACKGROUND

The Minimum Information for Studies Evaluating Biologics in Orthopedics (MIBO) guidelines were developed in May 2017 to encourage improved reporting standards, promote increased transparency and reproducibility, and enhance clinical evaluation capabilities. The MIBO guidelines consist of 23 checklist items considered necessary to critically appraise clinical studies evaluating platelet-rich plasma (PRP).

PURPOSE

To assess randomized controlled trials that evaluated PRP for the treatment of knee osteoarthritis in order to systematically review their adherence to the MIBO guidelines.

STUDY DESIGN

Systematic review. Level 1a.

METHODS

A search was performed following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The inclusion criteria were randomized controlled trials reporting on knee osteoarthritis treated with intra-articular PRP. The studies were categorized into pre-, peri-, and post-MIBO groups based on the start date of data collection. The overall MIBO scores, defined as percentage of checklist items out of the 23 checklist items reported in 1 study, individual item scores, defined as percentage of studies reporting the checklist item within a specified group, and overall item score defined as the average of the individual item scores from all the included studies were calculated.

RESULTS

The review included 87 studies (7925 patients; 8118 knees). Of these, 51 studies were assigned to the pre-MIBO group, 19 studies to the peri-MIBO group, and 17 studies to the post-MIBO group. The overall MIBO score was 72%. No statistically significant differences in MIBO scores were found among the 3 MIBO groups (P = .345). The majority of the studies (62 studies; 71%) had MIBO scores <80%. MIBO items with particularly low item scores included reporting of whole-blood characteristics (20%), platelet recovery rate (22%), PRP analysis (30%), and PRP activation (47%). No significant difference among the 3 MIBO groups was found for the item scores except for the reporting of the recipient details (P = .012).

CONCLUSION

This study highlights the deficiencies in adherence to the MIBO guidelines, particularly in reporting key variables such as whole-blood characteristics, platelet recovery rate, PRP analysis, and PRP activation. These findings suggest that the publication of the MIBO guidelines has not resulted in improved reporting practices in studies investigating intra-articular PRP for the treatment of knee osteoarthritis.

Comparison of hyaluronic acid and platelet-rich plasma in knee osteoarthritis: a systematic review

BACKGROUND

Knee osteoarthritis (KOA) is a common joint disorder, and intra-articular injections of hyaluronic acid (HA) or platelet-rich plasma (PRP) are frequently employed therapeutic interventions. However, there remains controversy regarding their efficacy. This systematic review aims to compare the effectiveness and safety of HA and PRP through a meta-analysis, with the objective of identifying the optimal treatment protocol for KOA and enhancing its management.

METHODS

Randomized controlled trials evaluating the clinical outcomes of patients receiving intra-articular injections of either HA or PRP were included as eligible studies. Two independent investigators assessed the selected studies and evaluated their risk of bias. Primary outcome measures included the Visual Analog Scale (VAS) score, the Western Ontario and McMaster Universities Arthritis Index (WOMAC) score, and other relevant assessment indices. Dichotomous variables were analyzed using risk ratios (RR) with 95% confidence intervals (CI). Data analysis was conducted using RevMan software (version 5.3).

RESULTS

A total of forty-two randomized controlled trials were included in this meta-analysis. No significant differences were observed between the patient populations in the two groups. The analysis demonstrated that PRP resulted in lower VAS and WOMAC scores compared to HA. Additionally, PRP exhibited superior performance across other evaluation indices. Notably, the incidence of adverse events was higher in the PRP group; however, all reported complications were mild.

CONCLUSIONS

Based on the current evidence, intra-articular injection of PRP appears to be more effective than HA for the treatment of KOA, as indicated by the analysis of VAS, WOMAC scores, and other evaluation indices.

TRIAL REGISTRATION

Retrospectively registered.

Long-term effectiveness of intra-articular injectables in patients with knee osteoarthritis: a systematic review and Bayesian network meta-analysis

BACKGROUND

Intra-articular injectables are proposed as a solution for pain relief and functional improvement in knee osteoarthritis (OA), however most studies involving intra-articular knee injectables are focused on short-term relief, leaving the recommendations regarding long-term management unclear. This network meta-analysis aimed to evaluate the mid- to long-term effectiveness of intra-articular knee injection of platelet-rich plasma (PRP), hyaluronic acid (HA), corticosteroids (CS), and their combinations for management of knee OA.

METHODS

Relevant studies were searched through PubMed, EMBASE, Scopus, and Cochrane Register of Trials databases from inception to 20th October, 2024 for randomized controlled trials (RCTs) of knee OA patients who had taken intra-articular injectable treatment with a follow-up duration of at least one year. The study included 37 RCTs involving 5089 patients. The outcomes assessed were pain relief and functional improvement of knee joint. The random effects Bayesian model was carried out for network meta-analysis. The surface under the cumulative ranking (SUCRA) curve demonstrated the rank probability of each injectable therapy for different outcomes.

RESULTS

Analysis revealed that, in terms of both knee pain relief and improvement of functional outcomes, the combined intra-articular injection of PRP and HA was ranked ahead of the isolated administration of PRP, followed by combination of HA with CS, HA alone, placebo, and CS at the end of one year.

CONCLUSION

These findings emphasize the sustained efficacy of PRP, particularly when combined with HA, in providing superior long-term pain relief and functional improvement in knee OA compared to other intra-articular injectables, highlighting its potential as a preferred treatment modality.

Most Orthopaedic Platelet-Rich Plasma Investigations Don't Report Protocols and Composition: An Updated Systematic Review

PURPOSE

To systematically review the literature to assess the heterogeneity of platelet-rich plasma (PRP) preparation and composition reporting for the treatment of musculoskeletal/orthopaedic pathologies.

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I and Level II studies from 2016 to 2022 that evaluated the use of PRP therapy for musculoskeletal pathologies. The search phrase used was "platelet-rich plasma clinical studies." Studies were assessed based on their reporting of the PRP preparation methods and reporting of PRP composition.

RESULTS

One hundred twenty-four studies (in 120 articles) met inclusion criteria for analysis. Of these studies, 15 (12.1%) provided comprehensive reporting, including a clear, well-described, and reproducible preparation protocol that future investigators can follow. Thirty-three studies (26.6%) quantitatively reported the final PRP product composition.

CONCLUSIONS

Among the studies using PRP for the treatment of musculoskeletal/orthopaedic pathologies, less than 20% provided a clear, well-described, and reproducible PRP preparation protocol, and only one-fourth of studies reported on the final PRP product composition.

CLINICAL RELEVANCE

A diverse current reporting of PRP composition between studies provides a high heterogeneity of the term "PRP," which becomes a limitation for a comparison of studies using PRP.

Bone Marrow Aspiration Concentrate in the Treatment of Osteoarthritis: A Review of its Current Clinical Application

BACKGROUND

Bone marrow aspiration concentrate (BMAC) has gained acceptance as a safe orthobiologic for treating osteoarthritis (OA), despite lacking robust supporting evidence. Although several publications have documented the use of BMAC in OA, evidence confirming its unequivocal efficacy remains limited.

METHODS

This review aims to summarize the current clinical evidence regarding BMAC as a therapeutic for OA, while also presenting the author's perspective. Sixteen studies were reviewed, including ten randomized clinical trials (RCTs) and six cohort studies.

RESULTS

From the review of existing literature, BMAC injections do not appear to significantly improve pain and function compared to conventional therapies such as hyaluronic acid and corticosteroids, although some studies report a longer duration of effectiveness. Furthermore, the evidence for structural improvement, which was the original rationale for cell therapy, is seldom reported.

CONCLUSION

In light of these findings, it is suggested that high-quality data from a large patient cohort is needed to determine the role of BMAC injections in OA treatment and address reimbursement issues. From the author's perspective, the introduction of a national registry system that provides valuable information on the cost-effectiveness of various orthopedic procedures may offer a solution.

Quality of life changes in patients suffering from knee osteoarthritis treated with bone marrow aspirate concentrate, platelet-rich plasma and hyaluronic acid injections

BACKGROUND

This study aimed to compare the effects of different treatments on quality of life in knee osteoarthritis patients. It focused on three therapies: bone marrow aspirate concentrate (BMAC), platelet-rich plasma (PRP), and hyaluronic acid (HA).

METHODOLOGY

The trial was conducted at a single center with 175 patients over a 12-month period with the knee OA, KL grade II-IV. Outcomes were measured using the WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index) and SF-36 scales, which assess physical and emotional well-being. Linear mixed models (LMMs) were used to analyze which treatment had the most positive impact on quality of life.

RESULTS

Patients treated with BMAC showed the most substantial improvement, particularly in physical health and mobility (p ≤ 0,001). PRP outperformed HA in some aspects, but BMAC consistently led to greater gains. The most notable enhancements were seen in areas like role limitations due to physical health and overall physical functioning.

CONCLUSIONS

The study suggested that BMAC treatment may contribute to improved quality of life in patients with knee osteoarthritis, particularly in terms of physical function. The correlation between WOMAC and SF-36 scores supports these findings, indicating a potential role for BMAC in enhancing mobility.

CLINICAL TRIAL REGISTRATION

NCT03825133 (ClinicalTrials.gov).

Management of knee osteoarthritis using bone marrow aspirate concentrate: a systematic review

INTRODUCTION

Knee osteoarthritis (OA) is a common degenerative joint condition and a major cause of disability in the general population.

SOURCE OF DATA

Recent published literature identified from PubMed, EMBASE, Google Scholar, and Scopus.

AREAS OF AGREEMENT

Orthobiological therapies try to regenerate articular cartilage and stop the progression of the degenerative lesion. Intra-articular injections of biological derivates have been increasingly used in the last decade.

AREAS OF CONTROVERSY

The indications for the use of bone marrow aspirate concentrate (BMAC) are still unclear.

GROWING POINTS

We systematically reviewed the current literature on BMAC in the management of knee OA, giving an update on the current indications for the selection of the ideal patient and the preparations and efficacy of BMAC compared to other biological alternatives.

AREAS TIMELY FOR DEVELOPING RESEARCH

BMAC is a valuable source of mesenchymal stem cells, offering potential benefits in attenuating the inflammatory pathway associated with knee OA. Intra-articular injection of BMAC has shown effectiveness in clinical trials improving functional outcomes of knee OA patients. The superiority of BMAC over other orthobiological treatments cannot be assessed because of conflicting results.

Comparison of Different Molecular Weights of Intra-Articular Hyaluronic Acid Injections for Knee Osteoarthritis: A Level I Bayesian Network Meta-Analysis

Background: The present Bayesian network meta-analysis compared the efficacy of intra-articular injections of different molecular weights of hyaluronic acid (HA) in patients with knee osteoarthritis. Methods: In November 2024, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. All randomised controlled trials investigating the efficacy of intra-articular HA injections for knee osteoarthritis were accessed. The outcome of interest was to evaluate pain according to the visual analogue scale (VAS). The groups included for comparison were the ultra-high molecular weight (UHMW), high molecular weight (HMW), medium molecular weight (MMW), and low molecular weight (LMW). Results: Data from 9822 patients were collected. The mean age of the patients was 62.1 ± 5.0 years with given comparability at baseline. Different follow-up periods were compared. The longest control period ranged from four to six months, and the UHMW and HMW injections were the interventions associated with the greatest reduction in the VAS. LMW HA was the intervention associated with the lowest decrease in VAS, falling short of the control group. Conclusions: The main findings of the present Bayesian network meta-analysis, with a current level I of evidence, suggests that the UHMW and HMW HA has a beneficial effect on pain at 6 months post intervention in patients with knee osteoarthritis.

Innovative Approaches in Knee Osteoarthritis Treatment: A Comprehensive Review of Bone Marrow-Derived Products

Knee osteoarthritis (OA) is a chronic articular disease characterized by the progressive degeneration of cartilage and bone tissue, leading to the appearance of subchondral cysts, osteophyte formation, and synovial inflammation. Conventional treatments consist of non-steroidal anti-inflammatory drugs (NSAIDs), analgesics, and glucocorticoids. However, the prolonged use of these drugs causes adverse effects. NSAIDs, for instance, are known to be nephrotoxic, increasing the damage to articular cartilage. New therapies capable of accelerating the process of tissue regeneration and repair are being discussed, such as the use of orthobiologics that are naturally found in the body and obtained through minimally invasive collection and/or laboratory manipulations. Bone marrow aspirate (BMA) and bone marrow aspirate concentrate (BMAC) are both rich in hematopoietic stem cells, mesenchymal stem cells (MSCs), and growth factors (GFs) that can be used in the healing process due to their anabolic and anti-inflammatory effects. The aim of this literature review is to assess the efficacy of BMA and BMAC in the treatment of knee OA based on the favorable results that researchers have obtained with the use of both orthobiologics envisaging an accelerated healing process and the prevention of OA progression.

Posterior iliac crest vs. proximal tibia: distinct sources of anti-inflammatory and regenerative cells with comparable 6-month clinical outcomes in treatment of osteoarthritis

BACKGROUND

Human bone marrow is a source of mesenchymal stem cells (MSCs), other progenitor cells, and factors with anti-inflammatory and regenerative capacity. Though the fraction of MSCs out of the nucleated cells is very small, bone marrow aspirate (BMA) for osteoarthritis (OA) has noteworthy effects. BMA is usually collected from the posterior or anterior iliac crest, and rarely from the proximal tibia. We investigated the clinically beneficial concentration of ex vivo MSCs, derived from BM harvested from the posterior iliac crest and proximal tibia by Marrow Cellution™ Aspiration System, and their phenotypic differences, in comparison to autologous Platelet-Rich Plasma (PRP) treatment prepared with a manual, closed system.

METHODS

A single-center, parallel, randomized controlled study was designed to investigate the efficacy of BMA from the posterior iliac crest compared to BMA from the proximal tibia, against a control group treated with PRP, in knee OA. Thirty patients with knee OA grade I-IV, according to Kellgren-Lawrence (KL), were distributed into each group. Visual Analog Scale (VAS) and Western Ontario & McMaster Universities Arthritis Index (WOMAC) score were used for clinical outcome evaluation.

RESULTS

Data from an intermediate analysis of 6-months follow-up, involving 15 patients in each arm, showed that the posterior iliac crest was significantly more densely populated with mononuclear cells, than the proximal tibia (p = 0.005). Flow cytometric analysis on ex vivo BMA showed a significantly greater number of MSCs in the BM-derived from the posterior iliac crest when compared with the proximal tibia (p < 0.001), together with a significantly higher number of platelets (PLTs) (p < 0.001). Surprisingly, despite these differences in cells number, the improvement in early pain and function scores, after each treatment, were statistically significant within each of the three arms. BM from the proximal tibia showed the highest ΔWOMAC, while BM from the posterior iliac crest showed the highest ΔVAS; however, these differences were not statistically significant across the three arms (p > 0.05). A better outcome, in terms of ΔVAS, was observed in patients classified as KL I-II, when treated with BMA from crest (p < 0.001) and PRP (p = 0.004). Moreover, the effect of BMA treatment on ΔVAS depends on MSCs % only in the Tibia Arm (r = -0.59, p = 0.021), where we also found a correlation between ΔWOMAC and monocytes (r = 0.75, p = 0.016).

CONCLUSION

The results indicate that the iliac crest yields a higher concentration of MSCs compared to the proximal tibia, however both BM, independently of the MSCs concentration, show a beneficial clinical outcome in the treatment of knee OA. Furthermore, BMA is not superior to PRP treatment.

Advanced Non-Operative Interventions for Anterior Knee Pain

PURPOSE OF REVIEW

This review presents evidence for advanced non-operative interventions, including extracorporeal shockwave therapy (ESWT), prolotherapy, platelet-rich plasma (PRP), adipose tissue-derived cells, bone marrow aspirate concentrate, various additional non-corticosteroid injectates, and needle-based interventions for common causes of anterior knee pain in the adult population. These etiologies include osteoarthritis of the knee, patellofemoral pain syndrome, chondromalacia patella, Hoffa fat pad impingement syndrome, patellar/quadriceps tendinopathy, and prepatellar bursitis. This review discusses patient care options using a case-based understanding of interventions by condition while recognizing strength of evidence.

RECENT FINDINGS

ESWT and PRP are the most robustly studied and have greatest evidence for treating tibiofemoral osteoarthritis and for long-term benefit in treating patellar tendinopathy. PRP may have evidence for treatment of chondromalacia and prolotherapy for management of tibiofemoral arthritis; both have limited evidence. Botulinum neurotoxin type A has strong evidence to support use in treating patellofemoral pain syndrome. There is limited evidence to support the use of viscosupplementation, percutaneous needle tenotomy, and medicinal signaling cell-based therapies beyond platelet-rich plasma for anterior knee pain. There is limited research on the management of quadriceps tendinopathy, prepatellar bursitis, patellofemoral osteoarthritis, and Hoffa's fat pad impingement syndrome. Further research and standardization of protocols are necessary to fully assess these treatments' efficacy. ESWT, cell-based, and needle-based interventions, may serve as effective treatment options for patients with anterior knee pain. Selection of each intervention requires understanding the evidence, level of risk, and appropriate application based on a patient's level of activity to enable clinicians to enhance patient outcomes and quality of life.

Bone Marrow Aspirate Concentrate Injections for the Treatment of Knee Osteoarthritis: A Systematic Review of Randomized Controlled Trials

Background

Osteoarthritis (OA) poses a significant global burden, with conventional treatments like corticosteroid and hyaluronic acid (HA) injections commonly used. Emerging injectable biologics, including bone marrow aspirate concentrate (BMAC), show promise in OA management.

Purpose

To investigate the clinical efficacy of BMAC injection compared with other injection treatments for knee OA.

Study Design

Systematic review; Level of evidence, 1.

Methods

A systematic review was conducted using PubMed, Embase, Cochrane Library, and Google Scholar to identify randomized controlled trials with Level 1 evidence that compared the clinical efficacy of BMAC with other injections. The visual analog scale for pain and the Pain subscale of the Knee injury and Osteoarthritis Outcome Score (KOOS) were used as clinical scores representing pain. For functional assessment, the Western Ontario and McMaster Universities Osteoarthritis Index and the International Knee Documentation Committee subjective form were used. For studies comparing BMAC with HA, each clinical score was standardized to pain and function scales based on the minimal clinically important difference (MCID).

Results

Eight studies, consisting of a total of 937 patients, were included. Patients treated with BMAC showed a significant improvement in clinical scores compared with baseline, starting at 1 month postinjection. For pain scores at 6-month (P = .033) and 12-month follow-up (P = .011), BMAC demonstrated favorable results over HA, with a statistically significant difference. However, these differences did not exceed the MCID. When BMAC was compared with other injections, no significant differences were observed in the degree of clinical score improvement. No serious adverse events or events significantly associated with BMAC compared with other treatments were reported.

Conclusion

BMAC injections demonstrated effectiveness in providing pain relief and functional improvement for patients with knee OA. When BMAC was compared with other intra-articular injection options, distinct differences surpassing the MCID were not evident. Further research is deemed necessary to investigate the role of BMAC in the treatment of knee OA.

Platelet-Rich Plasma for Knee and Hip Osteoarthritis Pain: A Scoping Review

PURPOSE OF REVIEW

Platelet-rich plasma (PRP) is an emerging biological intervention for osteoarthritis (OA), yet the outcomes remain uncertain. The purpose of this study was to review current literature regarding the use of PRP for knee and hip OA.

RECENT FINDINGS

Recent systematic reviews have found significant clinical improvements in outcomes after the administration of PRP compared to hyaluronic acid (HA) in patients with knee OA. One of these reviews included bone marrow aspirate concentrate (BMAC) as a comparison group and found no significant differences in outcomes between PRP and BMAC. Currently, the literature is lacking on whether leukocyte-rich or leukocyte-poor PRP is superior in patients with knee OA. The literature on PRP for hip OA has not provided consistent results as it has for the knee. Two recent systematic reviews evaluated RCTs for patients undergoing treatment with either PRP or HA for hip OA and found no significant differences in clinical outcomes between groups at final follow-up. Current literature regarding the association between OA grade and PRP efficacy has found varying results. The use of PRP injections in the treatment of knee OA appears to be favorable, resulting in clinically comparable or superior outcomes compared to other injection treatments. However, the clinical efficacy of PRP injections in hip OA is far less consistent. Evidence is lacking to suggest that the presence of leukocytes significantly influences clinical outcomes. Further randomized controlled trials on larger cohorts, with longer follow-up, and with comparable formulations are required before recommendations can be made regarding use of PRP for hip OA, the effect of leukocyte concentration, and clinical efficacy based on OA grade.

Clinical efficacy of mesenchymal stem cells and platelet-rich plasma in the therapy of osteoarthritis: a meta-analysis

BACKGROUND

Intra-articular administration of mesenchymal stem cells (MSCs) presents a novel methodology for managing osteoarthritis, but there is still no definite evidence of its efficacy.

AIM

To assess the comparative effectiveness of MSCs and platelet-rich plasma (PRP) for managing osteoarthritis by reviewing the literature and using meta-analysis.

METHODS

Randomized controlled trials and cohort studies comparing MSCs and PRP for managing osteoarthritis were included. We searched 'osteoarthritis', 'mesenchymal stem cell', 'platelet-rich plasma', and other words in Pubmed, Embase, and Cochrane Library database. The search period encompassed the entire duration of the databases, starting from its inception until April 2024. Two researchers conducted the literature search, extracting data, and evaluating quality as distinct processes. Meta-analysis was carried out using the software RevMan5.3, and the calculation of weighted mean difference (WMD) and 95% confidence interval (CI) were performed using either a fixed-effect model or a random-effects model.

RESULTS

Eleven studies were included, comprising 8 randomized controlled trials and 3 cohort studies. A total of 693 individuals participated in the study, of which 394 received intra-articular injections of MSCs (group A) and 299 received intra-articular injections of PRP (group B). The two groups were comparable in the five dimensions of knee injury and osteoarthritis outcome score (KOOS) [pain (WMD: 0.38, 95% CI: -3.62 to 4.38, P > 0.05), symptoms (WMD: -1.48, 95% CI: -5.90 to 2.94, P > 0.05), activities of daily living (ADL, WMD: -2.36, 95% CI: -6.87 to 2.14, P > 0.05), function in sport and recreation (Sport/Rec, WMD: -3.84, 95% CI: -10.60 to 2.92, P > 0.05), knee-related quality of life (QOL, WMD: 0.09, 95% CI: -5.48 to 5.67, P > 0.05)] and Western Ontario and McMaster Universities osteoarthritis index (WOMAC, WMD: 0.47, 95% CI: -3.76 to 4.70, P > 0.05). Compared with group A, the International Knee Documentation Committee Subjective Knee Form (IKDC, WMD: 4.19, 95% CI: 2.57 to 5.82, P < 0.001) score of group B was higher.

CONCLUSION

The short-term effectiveness of intra-articular administration of PRP for managing osteoarthritis is slightly better than that of MSCs. However, because of the limited quantity of incorporated research studies and the potential for bias, requisite in the future are studies of substantial size and superior quality.

Comparison of Pain and Complications between Outpatients and Inpatients Treated with Bone Marrow Aspirate Concentrate for Knee Osteoarthritis

Bone marrow aspirate concentrate (BMAC) has been increasingly used as an injectable treatment for knee osteoarthritis (OA). However, there remains a lack of studies on the pain and complications associated with BMAC treatment. This study compared the pain and complications of BMAC treatment between outpatients and inpatients with Kellgren-Lawrence grade II-III knee osteoarthritis (OA) during a follow-up period of ≥3 months. This study included 40 outpatients (40 knees) and 80 inpatients (80 knees) as controls who received BMAC articular injections for knee OA between December 2023 and March 2024. Outpatients were administered BMAC under local anesthesia alone, whereas inpatients were administered BMAC under local anesthesia and intravenous anesthesia. The outcomes were the visual analog scale (VAS) pain score during the BMAC procedure and the complications associated with harvest and injection sites. The mean VAS pain score in the outpatient group was significantly higher than that in the inpatient group during trocar insertion (5.2 vs. 1.3, p < 0.05) and bone marrow aspiration (6.2 vs. 1.4, p < 0.05), but it was similar between the two groups during BMAC injection (2.2 vs. 2.3, p = 0.858). Transient post-treatment complications were observed in 17.5% (7/40) of outpatients and 16.3% (13/80) of inpatients. No significant differences were observed in complications between the two groups, all of which were resolved within 2 months without any specific problem. Moreover, no major complications occurred in any group. In conclusion, outpatients who received only local anesthesia reported significant pain during BMAC treatment. The addition of intravenous anesthesia is necessary to alleviate pain during the BMAC procedure.

Systematic Review of Platelet-Rich Plasma in Medical and Surgical Specialties: Quality, Evaluation, Evidence, and Enforcement

Background: Platelet-rich plasma (PRP) is widely used in various medical and surgical specialties for its regenerative properties, including aesthetics (facial rejuvenation, hair restoration, and skin tightening) and orthopedics (treatment of tendinitis and osteoarthritis). However, the inconsistent literature on PRP's efficacy and safety leads to critical knowledge gaps. This systematic review evaluates quality control measures in PRP preparation and application and explores the regulatory environment governing its clinical use. Methods: Following PRISMA guidelines, a comprehensive search was conducted across multiple databases, including PubMed, EMBASE, and Web of Science, for studies published from January 2020 to April 2024. The review included randomized controlled trials (RCTs) involving human participants undergoing PRP treatment for aesthetic or regenerative purposes. Key parameters such as the PRP preparation methods, platelet concentration, and quality control measures were analyzed. The study protocol was registered with PROSPERO (ID: CRD42024557669). Results: Out of 75 RCTs involving 5726 patients, the review identified significant variability in PRP preparation methods and application techniques, including differences in centrifugation protocols and platelet concentration levels. A new evidence-based scoring system, the William-Eqram Scoring System for PRP Quality Reporting (WESS-PQR), was proposed to address these inconsistencies. Correlation analysis revealed a strong positive correlation (r = 0.79) between proper temperature control during preparation and PRP efficacy. Initial platelet count assessment showed a moderate positive correlation (r = 0.57) with efficacy. Conclusions: Standardized PRP preparation protocols and robust regulatory frameworks are urgently needed to ensure the safety and efficacy of PRP treatments. The proposed WESS-PQR scoring system can serve as a valuable tool for clinicians and researchers, promoting consistency and reliability in PRP applications.

Platelet-rich plasma intra-articular knee injections from open preparation techniques do not pose a higher risk of joint infection: A systematic review of 91 randomized controlled trials and 5914 injections

Purpose

To compare the infection rate of intraarticular platelet-rich plasma (PRP) knee injections between open and closed techniques in randomized controlled trials (RCTs) published in the last decade.

Methods

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, PubMed, Scopus and Virtual Health Library were accessed in October 2022 using the terms 'platelet-rich plasma', 'PRP', 'knee' and 'tibiofemoral' alone and in combination with Boolean operators AND/OR. RCTs published during the last 10 years evaluating PRP intra-articular knee injections were considered eligible. Studies were excluded if the kit/preparation technique was not described. Data were presented using individual studies' absolute values, totals, and pooled percentages. Publication bias was assessed using the ROBIS tool.

Results

Ninety-one studies met the predetermined eligibility criteria. Forty-one implemented a closed technique, while 50 were open. All studies implementing a closed technique disclosed their commercial kits. Only 16 studies (17.58%) failed to report joint infections. Among the studies reporting joint infections as outcomes, 30 implemented a closed technique with 1195 patients, 1921 intra-articular knee injections and 95.44% of patient follow-up. On the other hand, 45 of them implemented an open technique with 2290 patients, 3993 intra-articular knee injections and 97.07% of patient follow-up. No patient had a joint infection among the included studies. Thirty-three studies prepared their PRP in controlled environments (36.26%). Most studies did not report where the preparation occurred (48.35%). Only twelve studies disclosed using laminar flow during preparation (13.19%). The infection rate for both techniques was 0 per 1000 knee injections.

Conclusion

Open PRP preparation techniques do not pose a higher risk of joint infection and can lower manufacturing costs when appropriate facilities are available. However, PRP preparation setting and laminar flow implementation data are deficient, and minimal requirements for good manufacturing practices demand further studies while adhering to local and regional regulations.

Level of Evidence

Level I, systematic review of RCTs.

Short-Term Clinical Results of Single-Injection Autologous Bone Marrow Aspirate Concentrate (BMAC) as a Therapeutic Option/Tool in Knee Osteoarthritis

Purpose: Knee osteoarthritis (KOA) is a very common cartilage disorder affecting millions of people globally and is characterized by pain, stiffness, swelling, loss of articular cartilage, and osteophyte formation, resulting in disability. The presently available treatments for KOA are palliative. Hence, there is a need to explore a non-surgical treatment portfolio. Bone marrow aspirate concentrate (BMAC) is one of the predominant attention-drawing managements/treatments for KOA in recent times due to its potential advantages of disease-modifying and regeneration capacities. Principle: This study aimed to evaluate the role of single-injection autologous BMAC as a therapeutic option in the treatment of KOA and evaluate the functional and clinical outcomes of KOA patients. In this study, 132 patients with KOA (Kellgren and Lawrence (KL) grade II and III) were included as per the inclusion criteria. Autologous bone marrow was aspirated and separated, and concentrated bone marrow aspirate was administered into the knee joint of the affected individual. Results: At the end of the 12th month (end of the follow-up period), 95% of patients showed complete pain relief and improvement in joint function, which shows that the results were promising and encouraging. Unpaired t-test results also indicated that the two-tailed p-value is less than 0.0001, and the difference is extremely statistically significant. No adverse effects were observed in the study patients. Conclusions: BMAC therapy has potential, with satisfactory, efficient, and durable results in KL grades II and III in KOA patients. This can be a safe alternative therapy in the treatment of KOA, especially in the early grades of OA. In summary, to the best of our knowledge, this is the first study from India that evaluated BMAC efficacy both subjectively and objectively in KOA (KL-II and KL-III) patients.

A case series utilizing bone marrow aspirate concentrate, cancellous bone autograft, platelet-rich plasma and autologous fibrin for the treatment of femur nonunions

Aim: To assess the efficacy of a bioregenerative scaffold derived from bone marrow aspirate, cancellous bone autograft, platelet-rich plasma and autologous fibrin in treating supracondylar femur nonunions. Methods & materials: Three patients with nonunions following multiple surgical failures underwent bone stabilization and the application of a novel bioregenerative scaffold. x-rays and subjective scales were collected before surgery and at 6, 12 and 24 months post-surgery. Results: All nonunions exhibited healing with sufficient callus formation, as confirmed radiologically. After 6 months, all patients resumed full weight-bearing walking without pain. Statistical analysis showed improvements in all scales compared with pre-surgical values. Conclusion: This method presents itself as an option for treating supracondylar femur nonunions following multiple surgical failures.

Platelet-Rich Plasma, Bone Marrow Aspirate Concentrate, and Hyaluronic Acid Injections Outperform Corticosteroids in Pain and Function Scores at a Minimum of 6 Months as Intra-Articular Injections for Knee Osteoarthritis: A Systematic Review and Network Meta-analysis

PURPOSE

To compare the efficacy of common intra-articular injections used in the treatment of knee osteoarthritis, including corticosteroid (CS), hyaluronic acid (HA), platelet-rich plasma (PRP), and bone marrow aspirate concentrate (BMAC), with a minimum follow-up of 6-months.

METHODS

A literature search was conducted using the 2020 Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines in August 2022 in the following databases: PubMed/MEDLINE, Scopus, Cochrane Database of Controlled Trials, and the Cochrane Database of Systematic Reviews. Level I to II randomized clinical trials with a minimum follow-up of 6 months that investigated the treatments of interest were included. Patient-reported outcome scores for pain and function at baseline and at latest follow-up were extracted, and the change in scores was converted to uniform 0 to 100 scales. Arm-based Bayesian network meta-analysis using a random-effects model was created to compare the treatment arms in pain and function.

RESULTS

Forty-eight studies comprising a total of 9,338 knees were included. The most studied intra-articular injection was HA (40.9%), followed by placebo (26.2%), PRP (21.5%), CS (8.8%), and then BMAC (2.5%). HA and PRP both led to a significant improvement in pain compared with placebo. HA, PRP, and BMAC all led to a significant improvement in function scores when compared with placebo. Surface under the cumulative ranking curves (SUCRAs) of the interventions revealed that PRP, BMAC, and HA were the treatments with the highest likelihood of improvement in both pain and function, with overall SUCRA scores of 91.54, 76.46, and 53.12, respectively. The overall SUCRA scores for CS and placebo were 15.18 and 13.70, respectively.

CONCLUSIONS

At a minimum 6-month follow-up, PRP demonstrated significantly improved pain and function for patients with knee osteoarthritis compared with placebo. Additionally, PRP exhibited the highest SUCRA values for these outcomes when compared with BMAC, HA, and CS.

LEVEL OF EVIDENCE

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

Navigating the Therapeutic Landscape: A Comprehensive Review of Platelet-Rich Plasma and Bone Marrow Aspirate Concentrate in Knee Osteoarthritis

This comprehensive review provides an in-depth analysis of platelet-rich plasma (PRP) and bone marrow aspirate concentrate (BMAC) as potential treatments for knee osteoarthritis. It explores their mechanisms of action, clinical efficacy, safety considerations, and the importance of personalised treatment approaches. The review highlights promising findings regarding the ability of PRP and BMAC to alleviate symptoms, improve joint function, and potentially slow disease progression. It emphasises the need for further research into long-term outcomes, direct comparative studies, protocol standardisation, biomarker identification, and cost-effectiveness assessments to enhance clinical practice. While the review does not directly compare PRP and BMAC, it provides valuable insights into their respective roles in knee osteoarthritis management. The review aims to contribute to evidence-based advancements in regenerative therapies for knee osteoarthritis by addressing critical research priorities and refining treatment strategies.

Intra-articular injection of bone marrow aspirate concentrate (mesenchymal stem cells) in KL grade III and IV knee osteoarthritis: 4 year results of 37 knees

Cell based therapies are increasingly used and results of bone marrow aspirate concentrate (BMAC) show encouraging short- to middle term results, superior to hyaluronic acid and platelet rich plasma (PRP). Most studies describe patients with mild to moderate arthritis and results of patients with KL III and IV osteoarthritis of the knee are limited to short term evaluations. Hence, the aim of this prospective study was to investigate the mid-term outcome of BMAC injections in patients with severe osteoarthritis of the knee. The BMAC was retrieved from the iliac crest as previously published with the "reorientation technique" from the iliac crest in supine position in analgosedation and injected into the patients' osteoarthritic knees. Patients were followed-up for 4 years. WOMAC, IKDC, SF 36 and walking distance were measured in a total of 37 participants. There was an improvement of IKDC and WOMAC from the first year onwards and a significant improvement beginning from year 2 up to the mid-term follow-up: IKDC increased significantly from 56 ± 12 (range 34-81) to 73 ± 13 (range 45-100), p < 0.001. WOMAC decreased significantly from 40 ± 23 (range 6-96) to 18 ± 18 (range 0-67), p < 0.001. 35 of 37 knees improved regarding IKDC and WOMAC score from the first to the last follow-up. Not a single protheses had to be implanted. Elaborate statistical analysis was done to exclude covariates and confounders (age, time, BMI,…). In summary, this is the first study on BMAC injections into 37 osteoarthritic knees with a 4-year follow up showing significant improvements in IKDC and WOMAC scores, and with a 95% success rate and significant improvement in walking distance.Clinical relevance Describes the 4-year outcome of BMAC injections for knees with severe osteoarthritis.

Comparative effectiveness of intra-articular therapies in knee osteoarthritis: a meta-analysis comparing platelet-rich plasma (PRP) with other treatment modalities

INTRODUCTION

Knee osteoarthritis (KOA) is a progressive joint disease commonly treated with intra-articular injections, including platelet-rich plasma (PRP), hyaluronic acid (HA), or corticosteroids (CS). This updated meta-analysis aims to enhance the statistical power of the results and provide comprehensive clinical evidence that reflects the most current research. By doing so, the authors aim to suggest a reliable estimate for the development of guidelines, addressing the pressing need for effective and minimally invasive treatment options.

METHODS

PubMed, Scopus, clinicaltrials.gov, Cochrane Central were searched until March 2023, for randomized controlled trials (RCTs) comparing the effectiveness of intra-articular injectable therapies, including PRP, HA, CS, and placebo, in KOA. Data extraction involved baseline characteristics and outcome measures [Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores, Visual Analog Scale (VAS) pain scores, KOOS, and IKDC scores] at 1, 3, 6 and 12 months. Statistical analysis, including subgroup analysis, assessment of heterogeneity, and publication bias, was conducted using Review Manager.

RESULTS

Our meta-analysis of 42 studies involving 3696 patients demonstrated that PRP treatment resulted in significant pain relief compared to HA injections, as evidenced by improved WOMAC pain (MD: -0.74; 95% CI: -1.02 to -0.46; P≤0.00001; I 2=94%) and VAS pain (MD: -0.65; 95% CI: -1.24 to -0.06; P=0.03; I2=97%) outcomes. Similarly, PRP showed greater efficacy in reducing WOMAC pain (MD: -8.06; 95% CI: -13.62 to -2.51: P=0.004; I 2=96%) and VAS pain (MD: -1.11; 95% CI: -1.64 to -0.59; P≤0.0001; I 2=68%) compared to CS injections, with the most significant improvement observed at 6 months.

CONCLUSIONS

PRP is an effective treatment for KOA. It provides symptomatic relief, has the potential to reduce disease progression, and has sustained effects up to 12 months. PRP offers superior pain relief and functional enhancement compared to CS and HA injections.

Advances in Stem Cell-Based Therapies in the Treatment of Osteoarthritis

Osteoarthritis (OA) is a chronic, degenerative joint disease presenting a significant global health threat. While current therapeutic approaches primarily target symptom relief, their efficacy in repairing joint damage remains limited. Recent research has highlighted mesenchymal stem cells (MSCs) as potential contributors to cartilage repair, anti-inflammatory modulation, and immune regulation in OA patients. Notably, MSCs from different sources and their derivatives exhibit variations in their effectiveness in treating OA. Moreover, pretreatment and gene editing techniques of MSCs can enhance their therapeutic outcomes in OA. Additionally, the combination of novel biomaterials with MSCs has shown promise in facilitating the repair of damaged cartilage. This review summarizes recent studies on the role of MSCs in the treatment of OA, delving into their advantages and exploring potential directions for development, with the aim of providing fresh insights for future research in this critical field.

Platelet-Rich Plasma Therapy: An Effective Approach for Managing Knee Osteoarthritis

Platelet-rich plasma (PRP) is a promising non-invasive therapeutic intervention for knee osteoarthritis (KOA) that has generated significant interest due to anecdotal accounts of its efficacy, resulting in reduced recovery time in various orthopedic interventions. This systematic review examines the effectiveness of PRP in managing KOA. Specifically, it seeks to determine the extent to which PRP can treat KOA patients effectively, alleviate KOA symptoms, and improve patient outcomes. Additionally, the review aims to identify the optimal concentration and composition of PRP required to achieve therapeutic results in KOA. Furthermore, the review investigates whether PRP can modify the synovial environment structurally and immunologically to improve outcomes in KOA patients. We conducted a comprehensive literature search on PubMed, Orthogate, Clinicaltrials.gov, and Embase of clinical trials investigating PRP treatment in KOA patients in the last five years. The results indicated that PRP is effective in treating KOA patients. Evidence shows that PRP therapy can alleviate pain, enhance joint function, increase range of motion, and improve mobility in KOA patients. PRP was effective in treating KOA when the mean platelet concentration of PRP treatment was 4.83 to 5.91 times higher than the baseline whole blood platelet concentration. However, studies investigating PRP with a mean platelet concentration of 3.48 to 4.04 times higher than baseline failed to demonstrate statistically significant improvements. PRP therapy slowed down KOA progression, which validates its effectiveness in impeding further structural damage and arresting the degenerative impact of the disease. Nonetheless, further investigation is necessary to examine how PRP therapy can modify the progression of the disease. Furthermore, future research should identify the most effective platelet concentration levels that provide optimal symptom relief. There is a need for further research to identify the specific PRP configuration that is most pertinent in a clinical setting, as there is a lack of standardization in PRP manufacturing protocols, including the variety of experimental setups and dosing schedules utilized in different studies.

The role of osteoarthritis severity, BMI and age on clinical efficacy of bone marrow aspirate concentrate in the treatment of knee osteoarthritis

Aim: The aim of this study was to assess whether BMI, severity of knee osteoarthritis, age and gender have any influence on the final clinical results of bone marrow aspirate concentrate injection. Method: A total of 111 study participants with painful knee osteoarthritis and different characteristics concerning before mentioned factors underwent bone marrow aspirate concentrate (BMAC) therapy and were followed up for 1 year. Result: Significant pain and functional improvement were observed in all participant groups. Participants' age and BMI did not influence the clinical outcome, but there was an influence of OA severity, especially among older patients. Conclusion: This study shows that BMAC therapy is effective. Younger patients with milder OA changes could be better candidates for long-lasting and more efficient BMAC therapy. Clinical Trial Registration: NCT03825133 (ClinicalTrials.gov).

Current evidence on mesenchymal stem cells for hip osteoarthritis: a narrative review

There are limited data on the use of mesenchymal stem cell injections for hip osteoarthritis. The goal of this study was to evaluate the literature by analyzing outcomes and comparing methodologies. Online search of PubMed, SportsDiscus and Case Reports Keywords was completed using the keywords 'stem cells' and 'hip' and 'osteoarthritis'. Six studies met the inclusion and exclusion criteria. Five out the six studies had statistically significant improvement in patient reported outcomes after mesenchymal stem cell injections. Only two studies provided information on radiological changes and findings were positive. None of the studies reported major complications. Small series of non-randomized controlled trials completed to date in the use of mesenchymal stem cells for the treatment of hip osteoarthritis reported the procedures to be safe and provide a positive clinical response. Randomized controlled trials must be performed to further confirm mesenchymal stem cells as a treatment option for hip osteoarthritis.

Treatment of postherpetic neuralgia by bone marrow aspirate injection: A case report

BACKGROUND

Postherpetic neuralgia (PHN) is the most frequent and a difficult-to-treat complication of herpes zoster (HZ). Its symptoms include allodynia, hyperalgesia, burning, and an electric shock-like sensation stemming from the hyperexcitability of damaged neurons and varicella-zoster virus-mediated inflammatory tissue damage. HZ-related PHN has an incidence of 5%–30%, and in some patients, the pain is intolerable and can lead to insomnia or depression. In many cases, the pain is resistant to pain-relieving drugs, necessitating radical therapy.

CASE SUMMARY

We present the case of a patient with PHN whose pain was not cured by conventional treatments, such as analgesics, block injections, or Chinese medicines, but by bone marrow aspirate concentrate (BMAC) injection containing bone marrow mesenchymal stem cells. BMAC has already been used for joint pains. However, this is the first report on its use for PHN treatment.

CONCLUSION

This report reveals that bone marrow extract can be a radical therapy for PHN.

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.

Multiple Injections of Platelet-Rich Plasma Versus Hyaluronic Acid for Knee Osteoarthritis: A Systematic Review and Meta-Analysis of Current Evidence in Randomized Controlled Trials

In recent years, various clinical trials have focused on treating knee osteoarthritis (KOA) with multiple injections of platelet-rich plasma (PRP). However, compared with the multiple hyaluronic acid (m-HA) injections, the clinical efficacy of multiple PRP (m-PRP) injections for KOA still remains controversial among these studies. Therefore, we aimed to compare the clinical effectiveness of m-PRP injections with m-HA injections in the treatment of KOA in this systematic review. Relevant clinical trials were searched via bibliographic databases, including Medline, PubMed, Embase, Web of Science, and Cochrane Central Register of Controlled Trials, to compare the m-PRP and m-HA injections in the treatment of KOA. Finally, fourteen randomized controlled trials, including 1512 patients, showed the postoperative VAS, WOMAC, IKDC, or EQ-VAS scores and were enrolled in this systematic review. Compared with the group of intra-articular m-HA injections, the group of intra-articular m-PRP injections was lower in the VAS scores at 3-month (WMD = −0.25; 95%CI, −0.40 to −0.10, p = 0.0009) and 12-month (WMD = −0.64; 95%CI, −0.79 to −0.49, p < 0.00001) follow-ups. In addition, the group of intra-articular m-PRP injections was also lower in the WOMAC scores at 1-month (WMD = −1.23; 95%CI, −2.17 to −0.29, p = 0.01), 3-month (WMD = −5.34; 95%CI, −10.41 to −0.27, p = 0.04), 6-month (WMD = −11.02; 95%CI, −18.09 to −3.95, p = 0.002), and 12-month (WMD = −7.69; 95%CI, −12.86 to −2.52, p = 0.004) follow-ups. Furthermore, compared with the group of intra-articular m-HA injections, the group of intra-articular m-PRP injections was higher in the IKDC scores at 3-month (WMD = 7.45; 95%CI, 2.50 to 12.40, p = 0.003) and 6-month (WMD = 5.06; 95%CI, 1.94 to 8.18, p = 0.001) follow-ups. However, the long-term adverse side of m-PRP injections for KOA still needs more large-scale trials and long-term follow-ups.

Comparison of clinical efficiency between intra-articular injection of platelet-rich plasma and hyaluronic acid for osteoarthritis: a meta-analysis of randomized controlled trials

Background

Platelet-rich plasma (PRP) and hyaluronic acid (HA) are non-surgical treatments for osteoarthritis (OA), but the comparison of their efficiency is still inconclusive.

Objectives

The objectives of this study were to compare the efficacy of PRP and HA in the treatment of OA by meta-analysis and to explore the effects of different injection times and leukocyte concentration on the efficacy of PRP.

Design

Meta-analysis and subgroup analysis were conducted. The data were analyzed by Review Manager v5.4.1.

Data sources and methods

Articles were retrieved and screened from PubMed, the Cochrane Library, Web of Science, and Embase. The outcome included the total Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), the visual analog scale (VAS), adverse events (AEs), the International Knee Documentation Committee (IKDC), and the satisfaction rate.

Results

A total of 30 articles involving 2733 patients were included. The total WOMAC score and IKDC score of the PRP group were better than those of the HA group at the last follow-up time, while there was no significant difference in AEs, satisfaction rate, and VAS between the two groups. In our subgroup analysis, there was no significant difference between single-injection PRP and triple-injection PRP. Leukocyte-poor PRP (LP-PRP) was better than leukocyte-rich PRP (LR-PRP) in IKDC, but there was no significant difference between them in the other scores.

Conclusions

In the treatment of OA, compared with HA, PRP performed better in the improvement of the patient's function. There was no significant difference in VAS and AEs between the two groups, and the safety was comparable. LP-PRP looked to be superior to LR-PRP in functional recovery, but there appeared to be no significant difference in pain relief between them. There was no significant difference between single PRP and triple PRP in the subgroup analysis.

Interventional Therapies for Osteoarthritis: An Update

Osteoarthritis (OA) is one of the most common diseases worldwide and is expected to increase in incidence as the age of the general population rises. Both oral medications, such as NSAIDs, and surgical treatments used for OA management have limitations. Demand is rising for minimally invasive techniques such as intraarticular injections and percutaneous interventions for use in place of or in conjunction with oral medications and surgical therapies, and the past 2 decades have seen a rapid expanse in both pharmacologic and nonpharmacologic minimally invasive OA treatments. Image guidance with fluoroscopy, CT, or ultrasound is often used in conjunction with these procedures to achieve precise treatment localization to achieve maximal therapeutic effect. The choice of modality used for image guidance is often influenced by clinician experience, patient characteristics, and equipment availability. This article reviews the mechanisms of action, contraindications, complications, and efficacy of conventional and developing minimally invasive OA treatments. The minimally invasive treatment options described in this Review include therapeutic injections such as antiinflammatory agents, viscosupplements, and biologics, as well as nonpharmacologic treatments of subchondroplasty, nerve ablation, genicular artery embolization, intraarticular pulsed radiofrequency therapy, and MRI-guided focused ultrasound therapy.

Assessment of the effectiveness and satisfaction of platelet-rich plasma compared with hyaluronic acid in knee osteoarthritis at minimum 7-year follow-up: A post hoc analysis of a randomized controlled trial

Background: Knee osteoarthritis (KOA) can be effectively treated conservatively using platelet-rich plasma (PRP) injections into the affected joints. While the short-term therapeutic clinical benefits were well documented, the mid-term results remain undetermined. To clarify its efficacy, the mid-term clinical outcomes of intra-articular injections of either PRP or hyaluronic acid (HA) in KOA were compared. Methods: One hundred patients who complied with the inclusion criteria were randomized to undergo once a week 3 weeks, intra-articular injections of either PRP or HA. Patients were evaluated before the injection, at 3, 6, and a mean of 78.9 months of follow-up. Eighty-five patients reached the final evaluation. Data on survival, re-intervention, pain, function, imaging, and satisfaction were collected and analyzed. Results: With surgery for any reason as the endpoint, the cumulative survival rate of the PRP group was 90%, while that of the HA group was 74%. There was a significant difference between the two groups in the total re-intervention rate (56.7% vs 16.2%, p < 0.05). The comparative analyses showed significant intergroup differences in the visual analog scale (VAS) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC) (p < 0.01, p < 0.05, respectively) at the final follow-up. And base on the regression analyses, the type of treatment, age, and Kellgren-Lawrence (K-L) grade served as statistically an independent determinants of VAS (p < 0.001, p = 0.034, p < 0.001, respectively). Likewise, those variables independently determined WOMAC in our study. However, no difference was observed in the imaging evaluation, containing the K-L grade and Cartilage Lesion Score, between the two groups (p > 0.05). Besides, the satisfaction treated by the PRP was 78.6%, with a superiority compared with HA (55.8%, p < 0.05), and no complications were noted in the whole treatment process among patients who participated. Conclusion: PRP was more effective than HA in survival and re-intervention rates, VAS, and WOMAC, although there were no significant differences in the imaging evaluation between the two groups. Furthermore, patients treated with PRP were associated with higher satisfaction compared with HA.

Efficacy and safety of platelet-rich plasma combined with hyaluronic acid versus platelet-rich plasma alone for knee osteoarthritis: a systematic review and meta-analysis

Purpose

To systematically evaluate the curative efficacy and safety of platelet-rich plasma (PRP) combined with hyaluronic acid (HA) in the treatment of knee osteoarthritis (KOA), comparing with platelet-rich plasma alone.

Methods

Cochrane Library, PubMed, China National Knowledge Infrastructure (CNKI) and Embase were searched for randomized controlled trials (RCTs) and cohort studies regarding the efficacy and safety of platelet-rich plasma (PRP) combined with hyaluronic acid (HA) in the treatment of knee osteoarthritis (KOA) comparing with platelet-rich plasma alone before January 15, 2022. The methodological quality of the ultimately included studies was assessed comprehensively, and meta-analysis was implemented using RevMan 5.3 software.

Results

Thirteen articles (9 RCTs, 4 cohort studies), including 1118 patients, were covered. There was no significant difference between the PRP + HA therapy and PRP-alone therapy in VAS scores at 3 months, 6 months and 12 months, WOMAC total scores at 3 months and KOOS at 1 month and 6 months. Compared with PRP-alone therapy, PRP + HA therapy was associated with significantly better improvement in VAS scores at 1 month, WOMAC total scores at 6 months, KOOS at 3 months, IKDC scores at 6 months and Lequesne index scores at 3 and 6 months. However, the smallest treatment effect of VAS scores, WOMAC total scores, KOOS and IKDC scores did not exceed the minimum clinically important difference (MCID). However, PRP + HA therapy got a greater reduction in the rate of adverse events, compared with PRP-alone therapy.

Conclusion

The results of this meta-analysis indicated that PRP + HA therapy was not found to be superior to PRP-alone therapy in pain relief and function improvement for patients with KOA. However, combined PRP with HA injections was generally safer than PRP injections alone, by assessing the incidence of adverse events.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13018-022-03398-6.

Mesenchymal stem cells for subchondral bone marrow lesions: From bench to bedside

Subchondral bone marrow lesions (BMLs) are areas of disease within subchondral bone that appear as T1 hypointense and T2 hyperintense ill-defined areas of bone marrow on magnetic resonance imaging. The most common bone marrow lesions include subchondral lesions related to osteoarthritis, osteochondral defects, and avascular necrosis. Emerging therapies include autologous biologic therapeutics, in particular mesenchymal stem cells (MSCs), to maintain and improve cartilage health; MSCs have become a potential treatment option for BMLs given the unmet need for disease modification. Active areas in the preclinical research of bone marrow lesions include the paracrine function of MSCs in pathways of angiogenesis and inflammation, and the use of bioactive scaffolds to optimize the environment for implanted MSCs by facilitating chondrogenesis and higher bone volumes. A review of the clinical data demonstrates improvements in pain and functional outcomes when patients with knee osteoarthritis were treated with MSCs, suggesting that BM-MSCs can be a safe and effective treatment for patients with painful knee osteoarthritis with or without bone marrow lesions. Preliminary data examining MSCs in osteochondral defects suggest they can be beneficial as a subchondral injection alone, or as a surgical augmentation. In patients with hip avascular necrosis, those with earlier stage disease have improved outcomes when core decompression is augmented with MSCs, whereas patients in later stages post-collapse have equivalent outcomes with or without MSC treatment. While the evidence for the use of MSCs in conditions with associated bone marrow lesions seems promising, there remains a need for continued investigation into this treatment as a viable treatment option.

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Common BMLs include osteoarthritis, osteochondral defects, and avascular necrosis.

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Patients with knee osteoarthritis treated with MSCs show improved pain and function.

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MSCs used as subchondral injection or surgical augmentation in osteochondral defects

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Improved outcomes of early hip avascular necrosis after core decompression with MSCs

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Additional preclinical and clinical evidence of MSCs as treatment for BMLs is needed.

Percutaneous autologous bone marrow concentrate for knee osteoarthritis: patient-reported outcomes and progenitor cell content

PURPOSE

Knee osteoarthritis (OA) is a common, progressively debilitating joint disease, and the intra-articular injection of autologous bone marrow concentrate (BMC) may offer a minimally invasive method of harnessing the body's own connective tissue progenitor cells to counteract accompanying degenerative effects of the disease. However, the extent to which the progenitor cell content of BMC influences treatment outcomes is unclear. We sought to determine whether patient-reported outcome measures associated with BMC treatment for knee OA are related to the concentration of progenitor cells provided.

METHODS

In the present study, 65 patients (72 knees) underwent treatment for knee OA with autologous BMC and self-reported their outcomes for up to one year using follow-up questionnaires tracking function, pain, and percent improvement. A small fraction of each patient's BMC sample was reserved for quantification with a haematological analyzer and cryopreserved for subsequent analysis of potential connective tissue progenitor cells using a colony-forming unit fibroblast (CFU-F) assay.

RESULTS

Patients reported significant increases in function and overall percent improvement in addition to decreases in pain relative to baseline levels following treatment with autologous BMC that persisted through 12 months. Patients reporting improved outcomes (46 of 72 knees) received BMC injections having higher CFU-F concentrations than non-responding patients (21.1×10³ ± 12.4×10³ vs 14.3×10³ ± 7.0 x10³ CFU-F per mL). A progenitor cell concentration of 18×10³ CFU-F per mL of BMC was found to best differentiate responders from non-responders.

CONCLUSION

This study provides supportive evidence for using autologous BMC in the minimally invasive treatment of knee OA and suggests that increased progenitor cell content leads to improved treatment outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT03011398, 1/7/17.

Platelet Rich Plasma in the Repair of Articular Cartilage Injury: A Narrative Review

OBJECTIVE

This paper reviews the research of platelet-rich plasma (PRP) in articular cartilage injury repair, to assess the mechanism, utilization, and efficacy of PRP in the treatment of articular cartilage injury, hoping to provide a theoretical basis for the clinical application of PRP in the future.

MATERIALS AND METHODS

A comprehensive database search on PRP applications in cartilage repair was performed. Among them, the retrieval time range of PRP in clinical trials of repairing knee cartilage injury was from January 1, 2021 to January 1, 2022. Non-clinical trials and studies unrelated to cartilage injury were excluded.

RESULT

PRP can affect inflammation, angiogenesis, cartilage protection, and cellular proliferation and differentiation after articular cartilage injury through different pathways. In all, 13 clinical trials were included in the analysis.

CONCLUSION

PRP is an emergent therapeutic approach in tissue engineering. Most studies reported that PRP has a positive effect on cartilage injury, improving the joint function, meanwhile there is a lack of standardized standards. The technology of PRP in the repair and treatment of articular cartilage injury is worthy of further research.

Reorientation technique has benefits in bone marrow aspiration of stem cells

We treated patients with osteoarthritis of the knee using injections of bone marrow aspirate concentrate (stem cell therapy). Since multiple controversial harvesting methods using different sites, needles, volumes and techniques have been described, we aimed to compare those methods. Four different harvesting sites at the iliac crest, three different types of needles, three different types of volumes and two different harvesting techniques were compared in 48 bone marrow aspirations. The conventional technique (Group 1) was compared with a reorientation technique (Group 2). The number of leucocytes and CD34 + cells and the viability in bone marrow aspirate (BMA) were analysed with a CytoFLEX Flow Cytometer. The reorientation technique showed significantly higher cell counts than the conventional technique in all parameters. Leucocytes per nl increased from 5 ± 2 to 12 ± 4 (p < .001), and CD 34 + cells per μl increased from 40 ± 40 to 140 ± 98 (p = .003). There was no difference between anterior and posterior harvesting at the iliac crest or between use of a thick and use of a thin needle. Use of the reorientation technique, compared to employing the conventional technique, has a significant advantage since the number of leucocytes and CD34 + cells can be tripled. For the use of bone marrow aspirate in the case of arthritis, it might therefore be a future option to harvest a maximum cell yield through the new reorientation technique and to omit centrifugation. However, the clinical relevance of these findings remains the subject of future studies.

Level of Evidence: Level I.

Clinical relevance: Enhanced technique of BMA for knee surgeons to ensure the maximum cell yield for stem cell therapy in regenerative medicine.

The Current Status of Clinical Trials on Biologics for Cartilage Repair and Osteoarthritis Treatment: An Analysis of ClinicalTrials.gov Data

OBJECTIVE

Biologics are increasingly used for cartilage repair and osteoarthritis (OA) treatment. This study aimed to provide an overview of the clinical trials conducted on this subject.

DESIGN

Two-word combinations of two sets of key words "cartilage"; "joint"; "osteoarthritis" and "biologics"; "stem cells"; "cell implantation" were used to search the database of ClinicalTrials.gov and supplemented with searches of PubMed and EMbase. The registered trials were analyzed for clinical conditions, completion status, phases, and investigated biologics. Recently completed trials with posted/published results were summarized.

RESULTS

From 2000 to 2022, a total of 365 clinical trials were registered at ClinicalTrials.gov to use biologics for cartilage repair and OA treatment. Since 2006, the number of registered trials accelerated at an annual rate of 16.4%. Of the 265 trials designated with a phase, 72% were early Phase 1, Phase 1, and Phase 2. Chondrocytes and platelet-rich plasma (PRP) were studied in nearly equal number of early- and late-stage trials. Mesenchymal stem/stromal cells (MSCs) were the most commonly investigated biologics (38%) and mostly derived from bone marrow and adipose tissue (70%). In last 5 years, 32 of the 72 completed trials posted/published results, among which seven Phase 3 trials investigated chondrocytes, PRP, bone marrow aspirate concentrate, hyaluronic acid, collagen membrane, and albumin.

CONCLUSIONS

There was a rapid increase in the number of registered clinical trials in recent years, using a variety of biologics for cartilage repair and OA treatment. Majority of the biologics still require late-stage trials to validate their clinical effectiveness.

Role of Platelets in Osteoarthritis-Updated Systematic Review and Meta-Analysis on the Role of Platelet-Rich Plasma in Osteoarthritis

Platelets are an essential component of hemostasis, with an increasing role in host inflammatory processes in injured tissues. The reaction between receptors and vascular endothelial cells results in the recruitment of platelets in the immune response pathway. The aim of the present review is to describe the role of platelets in osteoarthritis. Platelets induce secretion of biological substances, many of which are key players in the inflammatory response in osteoarthritis. Molecules involved in cartilage degeneration, or being markers of inflammation in osteoarthritis, are cytokines, such as tumor necrosis factor α (TNFα), interleukins (IL), type II collagen, aggrecan, and metalloproteinases. Surprisingly, platelets may also be used as a treatment modality for osteoarthritis. Multiple randomized controlled trials included in our systematic review and meta-analyses prove the effectiveness of platelet-rich plasma (PRP) as a minimally invasive method of pain alleviation in osteoarthritis treatment.

Impact of the Process Variables on the Yield of Mesenchymal Stromal Cells from Bone Marrow Aspirate Concentrate

Human bone marrow (BM) has been highlighted as a promising source of mesenchymal stromal cells (MSCs) containing various growth factors and cytokines that can be potentially utilized in regenerative procedures involving cartilage and bone. However, the proportion of MSCs in the nucleated cell population of BM is only around 0.001% to 0.01% thereby making the harvesting and processing technique crucial for obtaining optimal results upon its use in various regenerative processes. Although several studies in the literature have given encouraging results on the utility of BM aspiration concentrate (BMAC) in various regenerative procedures, there is a lack of consensus concerning the harvesting variables such as choice of anesthetic agent to be used, site of harvest, size of the syringe to be used, anticoagulant of choice, and processing variables such as centrifugation time, and speed. In this review article, we aim to discuss the variables in the harvesting and processing technique of BMAC and their impact on the yield of MSCs in the final concentrate obtained from them.

Efficacy of Intra-Articular Injection of Platelet-Rich Plasma Combined with Mesenchymal Stem Cells in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-Analysis

OBJECTIVE

This study systematically evaluated the effect of intra-articular injection of platelet-rich plasma (PRP) and mesenchymal stem cells (MSC) on knee osteoarthritis (KOA).

METHODS

Randomized controlled trials (RCTs) of PRP combined with MSC in the treatment of KOA were collected from PubMed, Cochrane Library, Web of Science, Wiley online library, CNKI, and Wanfang databases from inception to July 30, 2022. Two researchers read and screened the literature to extract the data, respectively. After conducting a risk-of-bias assessment of included data, RevMan 5.3 software was used for meta-analysis. The Cochrane Handbook risk-of-bias assessment tool was used to evaluate the included literature.

RESULTS

A total of 9 papers with 480 KOA patients were included in this study. Significant differences in terms of visual analogue scale (VAS) score (MD = -1.10, 95% CI -1.91 to -0.29), P = 0.008) and knee injury and osteoarthritis outcome score (KOOS) (MD = 4.56, 95% CI 0.54-8.58, P = 0.050) were noted between the 2 groups. Subgroup analysis found that MD = 1.66 in KOOS-pain-1 group (95% CI (0.10, 3.22), P = 0.040), which is significant. The MD for KOOS total score and IKDC scores between the two groups was MD = 6.31 (95% CI 2.73-9.88, P = 0.0005) and MD = 3.05 (95% CI -7.09-13.20, P = 0.56), respectively.

CONCLUSION

The results of this study provide a theoretical basis for the clinical treatment of KOA with PRP combined with MSC.