Intra-articular injection of autologous adipose-derived stromal vascular fractions for knee osteoarthritis: a double-blind randomized self-controlled trial

Clinical Efficacy of Bone Marrow Aspirate Concentrate Versus Stromal Vascular Fraction Injection in Patients With Knee Osteoarthritis: A Systematic Review and Meta-analysis

BACKGROUND

Knee injection using either bone marrow aspirate concentrate (BMAC) or stromal vascular fraction (SVF) from adipose tissue has been shown to result in symptomatic improvement in patients with knee osteoarthritis (OA). It is still unclear whether one of these therapies is superior over the other.

PURPOSE

To systematically report the clinical studies evaluating BMAC and SVF in the treatment of knee OA and to compare the clinical efficacy of these 2 injection therapies.

STUDY DESIGN

Meta-analysis; Level of evidence, 4.

METHODS

This meta-analysis was performed per the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines. Studies were included if they reported the clinical outcomes after a single BMAC or SVF injection in the knee joint of patients with OA. Studies evaluating preparations of culture-expanded stem cells were excluded. A random effects model was used; the clinical efficacy of BMAC or SVF injection was assessed using the standardized mean difference (SMD) and compared. Visual analog scale (VAS) scores for pain and Western Ontario and McMaster Universities Osteoarthritis (WOMAC) knee index were the primary outcomes. The level of statistical significance was set at P < .05.

RESULTS

Ten studies and 472 patients with knee OA who received either BMAC (233 patients) or SVF (239 patients) were included. Patients who received an injection had improved VAS outcomes (mean ± SD): from 5.8 ± 1.3 to 2.6 ± 17 for BMAC and from 6.4 ± 1.4 to 3.4 ± 0.5 for SVF. They also experienced significantly reduced pain (SMD [VAS], 2.6 for BMAC and 3.4 for SVF) and improved function (SMD [WOMAC], 1.4 for BMAC and 1.2 for SVF). However, the SVF injection had a significantly greater effect on pain reduction than did the BMAC injection (P < .0001). Based on WOMAC, the clinical effect of BMAC versus SVF knee injection in patients with knee OA was equivalent (P = .626). Results were limited by the presence of publication bias as well as variability in the preparation methods utilized in the BMAC and SVF injection protocols. Complications were reported in 50% of the BMAC studies (knee stiffness, persistent knee swelling) and 67% of the SVF studies (knee swelling, knee pain, positive SVF cultures without symptoms of infection, and bleeding at the abdominal harvest site).

CONCLUSION

A single BMAC or SVF injection into the knee joint of patients with OA resulted in symptomatic improvement at short-term follow-up. However, SVF seemed to be more effective than did BMAC in the reduction of knee pain. There was significant variation in the BMAC and SVF injection preparation techniques used across the studies and a lack of stratification of outcomes based on the radiologic classification of OA. Therefore, these results should be taken with caution.

Methodological quality and risk of bias of systematic reviews and meta-analyses on stem cells for knee osteoarthritis: A cross-sectional survey

Clinical guidelines need high-quality studies to support clinical decision-making, in which the evidence often was collected from systematic reviews (SRs) and/or meta-analyses (MAs). At present, the methodological quality and risk of bias (RoB) of SRs/MAs on stem cell therapy for the treatment of knee osteoarthritis (KOA) has been poorly investigated. This study aims to strictly evaluate the methodological quality and RoB in SRs/MAs of stem cell therapy for KOA. Four electronic databases (PubMed, Embase, Cochrane Library, and Web of Science databases) were searched, from inception to October 5th, 2021. SRs/MAs involving randomized control trials (RCTs) or cohort studies on stem cell therapy for the treatment of KOA were included. The methodological quality and RoB were assessed using AMSTAR 2 and ROBIS tool respectively. In total, 22 SRs/MAs were included. According to the results obtained by AMSTAR 2 tool, all SRs/MAs were rated as "Critically low". Main methodological weaknesses were as follows: up to 81.82% did not meet protocol registration requirements, only 13.64% provided a list of excluded studies and justification, and 13.64% investigated and discussed the publication bias.. ROBIS-based RoB assessment showed that all the SRs/MAs were rated as "High". Besides, the lack of following the implementation of the PRISMA reporting guideline seems to reduce the methodological quality of the studies. The overall methodological quality of the SRs/MAs concerning the application of stem cell therapy in treating KOA is "Critically low", while the RoB is high. It is difficult to provide effective evidence for the formulation of guidelines for KOA treatment. We suggest that the relevant methodological quality assessment should be carried out in the future before the SRs/MAs are used as clinical evidence. In addition, it may be necessary for many journals to include the checklist with a submitted manuscript.

Mid-term prognosis of the stromal vascular fraction for knee osteoarthritis: a minimum 5-year follow-up study

Background

The short-term safety and efficacy of stromal vascular fraction (SVF) in treating knee osteoarthritis (KOA) have been extensively studied but the mid-term and long-term prognoses remain unknown.

Methods

126 KOA patients were recruited and randomly assigned to SVF group and hyaluronic acid (HA) group (control group). The scores of visual analogue scale (VAS) and the Western Ontario and McMaster University Osteoarthritis Index (WOMAC) were assessed and compared between the two groups 1, 2, 3, and 5 years after treatment. The endpoint was defined as surgeries related to KOA or clinical scores exceeding the patient acceptable symptom state (PASS).

Results

The VAS and WOMAC scores in the SVF group were significantly better than those in the HA group during the 5-year follow-up after treatment. The average responsive time to SVF treatment (61.52 months) was significantly longer than HA treatment (30.37 months). The adjusted Cox proportional hazards model showed that bone marrow lesion (BML) severity, body mass index (BMI) and treatment were independent risk factors and that the use of SVF reduced the risk of clinical failure by 2.602 times. The cartilage volume was reduced in both the SVF and control groups at 5 years but reduced less in the SVF group.

Conclusions

Up to 5 years after SVF treatment, acceptable clinical state was present for approximately 60% of patients. BML severity and BMI were independent predictors of the prognosis.

Trial Registry: This study was retrospectively registered at Chinses Clinical Trial Registry with identifier ChiCTR2100052818 and was approved by ethics committee of the First Affiliated Hospital of Zhejiang Chinese Medical University, number 2013-X-063.

Methodological Flaws in Meta-Analyses of Clinical Studies on the Management of Knee Osteoarthritis with Stem Cells: A Systematic Review

(1) Background: Conclusions of meta-analyses of clinical studies may substantially influence opinions of prospective patients and stakeholders in healthcare. Nineteen meta-analyses of clinical studies on the management of primary knee osteoarthritis (pkOA) with stem cells, published between January 2020 and July 2021, came to inconsistent conclusions regarding the efficacy of this treatment modality. It is possible that a separate meta-analysis based on an independent, systematic assessment of clinical studies on the management of pkOA with stem cells may reach a different conclusion. (2) Methods: PubMed, Web of Science, and the Cochrane Library were systematically searched for clinical studies and meta-analyses of clinical studies on the management of pkOA with stem cells. All clinical studies and meta-analyses identified were evaluated in detail, as were all sub-analyses included in the meta-analyses. (3) Results: The inconsistent conclusions regarding the efficacy of treating pkOA with stem cells in the 19 assessed meta-analyses were most probably based on substantial differences in literature search strategies among different authors, misconceptions about meta-analyses themselves, and misconceptions about the comparability of different types of stem cells with regard to their safety and regenerative potential. An independent, systematic review of the literature yielded a total of 183 studies, of which 33 were randomized clinical trials, including a total of 6860 patients with pkOA. However, it was not possible to perform a scientifically sound meta-analysis. (4) Conclusions: Clinicians should interpret the results of the 19 assessed meta-analyses of clinical studies on the management of pkOA with stem cells with caution and should be cautious of the conclusions drawn therein. Clinicians and researchers should strive to participate in FDA and/or EMA reviewed and approved clinical trials to provide clinically and statistically valid efficacy.

Micro-fragmentation is a valid alternative to cell expansion and enzymatic digestion of adipose tissue for the treatment of knee osteoarthritis: a comparative preclinical study

PURPOSE

The aim of this study was to compare three procedures to exploit adipose-derived cells for the treatment of osteoarthritis (OA) in a preclinical model, to understand their therapeutic potential and identify the most suitable approach for the clinical application.

METHODS

Biological samples from adipose tissue, processed by mechanical micro-fragmentation (MF), enzymatic digestion (SVF) or cell expansion (ADSCs), were first characterized in vitro and then used in vivo in a surgically induced OA rabbit model: Group 1-control group (untreated 12 knees/saline 12 knees), Group 2-MF (24 knees), Group 3-SVF (24 knees), Group 4-ADSCs (24 knees). Macroscopic, histological, histomorphometric, immunohistochemical and blood and synovial fluid analyses were evaluated at 2 and 4 months from the treatments.

RESULTS

Samples obtained by the three procedures yielded 85-95% of viable cells. In vivo assessments showed no significant side effects or inflammatory responses after the injection. The macroscopic Hanashi score did not show significant differences among treated groups and controls. The histopathological evaluation of synovial tissues showed lower signs of synovitis for MF, although the semiquantitative analysis (Krenn score) did not reach statistical significance. Instead, MF showed the best results both in terms of qualitative and semi-quantitative evaluations of articular cartilage, with a more uniform staining, a smoother surface and a significantly better Laverty score (p = 0.004).

CONCLUSION

MF, SVF, and expanded ADSCs did not elicit significant local or systemic adverse reactions in this preclinical OA model. Among the different methods used to exploit the adipose tissue potential, MF showed the most promising findings in particular in terms of protection of the articular surface from the joint degenerative OA processes.

LEVEL OF EVIDENCE

Preclinical animal study.

Therapeutic effect of adipose stromal vascular fraction spheroids for partial bladder outlet obstruction induced underactive bladder

BACKGROUND

Underactive bladder (UAB) is a common clinical problem but related research is rarely explored. As there are currently no effective therapies, the administration of adipose stromal vascular fraction (ad-SVF) provides a new potential method to treat underactive bladder.

METHODS

Male Sprague-Dawley rats were induced by partial bladder outlet obstruction (PBOO) for four weeks and randomly divided into three groups: rats treated with PBS (Sham group); rats administrated with ad-SVF (ad-SVF group) and rats performed with ad-SVF spheroids (ad-SVFsp group). After four weeks, urodynamic studies were performed to evaluate bladder functions and all rats were sacrificed for further studies.

RESULTS

We observed that the bladder functions and symptoms of UAB were significantly improved in the ad-SVFsp group than that in the Sham group and ad-SVF group. Meanwhile, our data showed that ad-SVF spheroids could remarkably promote angiogenesis, suppress cell apoptosis and stimulate cell proliferation in bladder tissue than that in the other two groups. Moreover, ad-SVF spheroids increased the expression levels of bFGF, HGF and VEGF-A than ad-SVF. IVIS Spectrum small-animal in vivo imaging system revealed that ad-SVF spheroids could increase the retention rate of transplanted cells in bladder tissue.

CONCLUSIONS

Ad-SVF spheroids improved functions and symptoms of bladder induced by PBOO, which contributes to promote angiogenesis, suppress cell apoptosis and stimulate cell proliferation. Ad-SVF spheroids provide a potential treatment for the future patients with UAB.

Intraarticular injection of microfragmented adipose tissue plus arthroscopy in isolated primary patellofemoral osteoarthritis is clinically effective and not affected by age, BMI, or stage of osteoarthritis

Purpose

This study aimed to report the clinical and functional results of a series of patients with isolated primary patellofemoral osteoarthritis (PFOA) treated with intraarticular injection of microfragmented autologous adipose tissue plus knee arthroscopy. The results were also analyzed in relation to the age and body mas index (BMI) of patients, and to the stage of PFOA.

Methods

Twenty-three patients with early-to-moderate (stage 1–3 according to the Iwano classification system) PFOA who received this treatment were retrospectively analyzed, with a mean follow-up of 22.1 ± 4.2 months. Patients were assessed using the International Knee Society (IKS) knee and function and visual analog scale (VAS) scores, and relative to their capacity for climbing stairs. Differences in improvements of IKS and VAS scores in relation to age (< 60 versus ≥ 60 years), BMI (< 30 versus ≥ 30 kg/m²), and stage of PFOA (stages 1–2 versus stage 3) were finally analyzed.

Results

The mean IKS knee score significantly improved from 35.6 ± 14.9 points preoperatively to 61.9 ± 17.8 points at the latest follow-up, while the mean IKS function score significantly improved from 52.0 ± 14.7 points preoperatively to 82.3 ± 19.1 points at the latest follow-up. The mean VAS score significantly decreased from 8.7 ± 2.2 preoperatively to 5.2 ± 2.5 at the latest follow-up. A significant improvement in the capacity to climb stairs was found. No significant differences in improvements of IKS knee and function and VAS scores were found in relation to age, BMI, or stage of PFOA.

Conclusion

Intraarticular injection of microfragmented autologous adipose tissue following arthroscopic debridement significantly improved overall clinical and functional scores in patients with early or moderate isolated primary PFOA at a mean follow-up of almost 2 years. Improvements were not significantly affected by age, BMI, or stage of PFOA.

Level of evidence

Level IV, retrospective case series.

Does vehicle-based delivery of mesenchymal stromal cells give superior results in knee osteoarthritis? Meta-analysis of randomized controlled trials

STUDY DESIGN

Meta-analysis.

OBJECTIVES

We aim to analyze and compare the efficacy and safety of vehicle-based delivery of Mesenchymal Stromal Cells (MSCs) in the management of osteoarthritis of the knee from Randomized Controlled Trials (RCTs) available in the literature.

MATERIALS AND METHODS

We conducted independent and duplicate electronic database searches including PubMed, Embase, Web of Science, and Cochrane Library till August 2021 for RCTs analyzing the efficacy and safety of vehicle-based delivery of MSCs in the management of knee osteoarthritis. Visual Analog Score (VAS) for Pain, Western Ontario McMaster Universities Osteoarthritis Index (WOMAC), Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score, and adverse events were the outcomes analyzed. Analysis was performed in R-platform using OpenMeta [Analyst] software.

RESULTS

21 studies involving 936 patients were included for analysis. None of the studies made a direct comparison of the direct and vehicle-based delivery of MSCs, hence we pooled the results of all the included studies of both groups and made a comparative analysis of their outcomes. Although at 6 months, both direct and vehicle-based delivery of MSCs showed significantly better VAS improvement (p = 0.002, p = 0.010), it was not consistent at 1 year for the vehicle delivery (p = 0.973). During 6 months and 12 months, direct delivery of MSCs (p < 0.001, p < 0.001) outperformed vehicle delivery (p = 0.969, p = 0.922) compared to their control based on WOMAC scores respectively. Both direct (p = 0.713) and vehicle-based delivery (p = 0.123) of MSCs did not produce significant adverse events compared to their controls.

CONCLUSION

Our analysis of literature showed that current clinically employed methods of vehicle-based delivery of MSCs such as platelet-rich plasma, hyaluronic acid did not demonstrate superior results compared to direct delivery, concerning the efficacy of treatment measured by improvement in pain, functional outcomes, and safety. Hence, we urge future clinical trials to be conducted to validate the effectiveness of advanced delivery vehicles such as composite bioscaffolds to establish their practical utility in cartilage regeneration with respect to its encouraging in-vitro evidence.

The Effect of Autologous Adipose-Derived Stromal Vascular Fractions on Cartilage Regeneration Was Quantitatively Evaluated Based on the 3D-FS-SPGR Sequence: A Clinical Trial Study

Background

Numerous reports confirmed the safety and clinical efficacy of autologous adipose-derived stromal vascular fractions (SVF), which have recently been used to treat osteoarthritis (OA). However, there is still no consensus as to whether SVF can promote cartilage regeneration. Herein, the purpose of our study was to evaluate the effectiveness of SVF versus hyaluronic acid (HA) in cartilage regeneration by establishing a cartilage model based on the three-dimensional fat-suppressed spoiled gradient recalled echo (3D-FS-SPGR) sequence.

Methods

Patients with symptomatic OA were recruited in our research, who were randomized into two groups. Meanwhile, patients in Kellgren-Lawrence (K-L) grades 2 and 3 were distinguished in each group. In the test group, patients received SVF injections of the knee, while patients in the control group received the same dose of HA. Each patient underwent the 3D-FS-SPGR sequence to establish a cartilage model at baseline, 6 months, and 12 months, respectively. The cartilage was characterized into six regions, and relevant parameters of the cartilage model were counted. Clinical and radiographic scores were recorded in one-year follow-up.

Results

In all regions, the thickness and volume of cartilage defect and the volume of healthy cartilage were improved to some extent in the test group, especially the medial femoral condyle (MF) and medial tibial condyle (MT). In grades 2 and 3, the thickness and volume of cartilage defect decreased by 0.92 ± 0.18 mm and 1.03 ± 0.23 mm and 84.00 ± 32.30 mm³ and 130.30 ± 49.56 mm³ in MF and by 0.96 ± 0.22 mm and 0.99 ± 0.14 mm and 64.18 ± 21.40 mm³ and 95.11 ± 19.93 mm³ in MT, respectively. No such phenomenon was observed in the control group. Meanwhile, the SVF-treated knees showed significant improvement in clinical and radiographic scores at 12 months. Nevertheless, these scores of the control group became worse at 12-month follow-up visit.

Conclusion

Taken together, this study shows that intra-articular injection of SVF markedly improved the clinical symptoms without adverse events, thereby repairing the damaged articular cartilage through cartilage regeneration.

Knee intra-articular administration of stromal vascular fraction obtained from adipose tissue: A systematic review

Osteoarthritis is a debilitating chronic degenerative disease of cartilage joint surfaces and the knee is the weight-bearing joint most frequently plagued. Intra-articular cell therapies have recently emerged as a method to manage knee osteoarthritis. A literature search identifying all articles involving use of SVF to treat knee osteoarthritis was performed, consulting several databases. In conclusion, 24 clinical trials analysed report good to excellent clinical and radiographic results for the treatment of knee OA with the use of intraarticular administration of SVF.

The Effects of Autologous Fat Transfer in an In Vitro Model of Basal Joint Osteoarthritis

PURPOSE

Basal joint osteoarthritis (OA) is a highly prevalent and debilitating condition. Recent clinical evidence suggests that autologous fat transfer (AFT) may be a promising, minimally invasive treatment for this condition. However, the mechanism of action is not fully understood. It is theorized that AFT reduces inflammation in the joint, functions to regenerate cartilage, or acts as a mechanical buffer. The purpose of this study was to better understand the underlying mechanism of AFT using an in vitro model. We hypothesize that the addition of stromal vascular fraction (SVF) cells will cause a reduction in markers of inflammation.

METHODS

Articular chondrocytes were expanded in culture. Liposuction samples were collected from human subjects and processed similarly to AFT protocols to isolate SVF rich in adipose-derived stem cells. A control group was treated with standard growth media, and a positive control group (OA group) was treated with inflammatory cytokines. To mimic AFT, experimental groups received inflammatory cytokines and either a low or high dose of SVF. Expression of relevant genes was measured, including interleukin (IL)-1ß, IL-1 receptor antagonist, and matrix metalloproteinases (MMP).

RESULTS

Compared to the OA group, significant decreases in IL-1ß, MMP3, and MMP13 expression on treatment day 3 were found in the high-dose SVF group, while MMP13 expression was also significantly decreased in the low-dose SVF group on day 3.

CONCLUSIONS

In this study, we found that SVF treatment reduced expression of IL-1ß, MMP3, and MMP13 in an in vitro model of OA. These results suggest that an anti-inflammatory mechanism may be responsible for the clinical effects seen with AFT in the treatment of basal joint OA.

CLINICAL RELEVANCE

An anti-inflammatory mechanism may be responsible for the clinical benefits seen with AFT for basal joint arthritis.

Is Culture Expansion Necessary in Autologous Mesenchymal Stromal Cell Therapy to Obtain Superior Results in the Management of Knee Osteoarthritis?-Meta-Analysis of Randomized Controlled Trials

Study Design: Meta-analysis. Objectives: We aimed to analyze the impact of cultured expansion of autologous mesenchymal stromal cells (MSCs) in the management of osteoarthritis of the knee from randomized controlled trials (RCTs) available in the literature. Materials and Methods: We conducted independent and duplicate electronic database searches including PubMed, Embase, Web of Science, and Cochrane Library until August 2021 for RCTs analyzing the efficacy and safety of culture-expanded compared to non-cultured autologous MSCs in the management of knee osteoarthritis. The Visual Analog Score (VAS) for pain, Western Ontario McMaster University's Osteoarthritis Index (WOMAC), Lysholm score, Knee Osteoarthritis Outcome Score (KOOS), and adverse events were the analyzed outcomes. Analysis was performed in R-platform using OpenMeta [Analyst] software. Results: Overall, 17 studies involving 767 patients were included for analysis. None of the studies made a direct comparison of the culture expanded and non-cultured MSCs, hence we pooled the results of all the included studies of non-cultured and cultured types of MSC sources and made a comparative analysis of the outcomes. At six months, culture expanded MSCs showed significantly better improvement (p < 0.001) in VAS outcome. Uncultured MSCs, on the other hand, demonstrated significant VAS improvement in the long term (12 months) in VAS (p < 0.001), WOMAC (p = 0.025), KOOS score (p = 0.016) where cultured-expanded MSCs failed to demonstrate a significant change. Culturing of MSCs did not significantly increase the complications noted (p = 0.485). On sub-group analysis, adipose-derived uncultured MSCs outperformed culture-expanded MSCs at both short term (six months) and long term (12 months) in functional outcome parameters such as WOMAC (p < 0.001, p = 0.025), Lysholm (p < 0.006), and KOOS (p < 0.003) scores, respectively, compared to their controls. Conclusions: We identified a void in literature evaluating the impact of culture expansion of MSCs for use in knee osteoarthritis. Our indirect analysis of literature showed that culture expansion of autologous MSCs is not a necessary factor to obtain superior results in the management of knee osteoarthritis. Moreover, while using uncultured autologous MSCs, we recommend MSCs of adipose origin to obtain superior functional outcomes. However, we urge future trials of sufficient quality to validate our findings to arrive at a consensus on the need for culture expansion of MSCs for use in cellular therapy of knee osteoarthritis.

Method Categorization of Stem Cell Therapy for Degenerative Osteoarthritis of the Knee: A Review

Current clinical applications of mesenchymal stem cell therapy for osteoarthritis lack consistency because there are no established criteria for clinical processes. We aimed to systematically organize stem cell treatment methods by reviewing the literature. The treatment methods used in 27 clinical trials were examined and reviewed. The clinical processes were separated into seven categories: cell donor, cell source, cell preparation, delivery methods, lesion preparation, concomitant procedures, and evaluation. Stem cell donors were sub-classified as autologous and allogeneic, and stem cell sources included bone marrow, adipose tissue, peripheral blood, synovium, placenta, and umbilical cord. Mesenchymal stem cells can be prepared by the expansion or isolation process and attached directly to cartilage defects using matrices or injected into joints under arthroscopic observation. The lesion preparation category can be divided into three subcategories: chondroplasty, microfracture, and subchondral drilling. The concomitant procedure category describes adjuvant surgery, such as high tibial osteotomy. Classification codes were assigned for each subcategory to provide a useful and convenient method for organizing documents associated with stem cell treatment. This classification system will help researchers choose more unified treatment methods, which will facilitate the efficient comparison and verification of future clinical outcomes of stem cell therapy for osteoarthritis.

Comparative effectiveness of nonsurgical interventions in the treatment of patients with knee osteoarthritis: A PRISMA-compliant systematic review and network meta-analysis

BACKGROUND

To find out, based on the available recent randomized controlled trials (RCTs), if the nonsurgical interventions commonly used for knee osteoarthritis patients are valid and quantify their efficiency.

METHODS

The database of MEDLINE and EMBASE were searched for RCTs evaluating nonsurgical treatment strategies on patients with mild to moderate knee osteoarthritis. A Bayesian random-effects network meta-analysis was performed. The primary outcome was the mean change from baseline in the Western Ontario and McMaster university (WOMAC) total score at 12 months. Raw mean differences with 95% credibility intervals were calculated. Treatments were ranked by probabilities of each treatment to be the best.

RESULTS

Thirteen trials assessed 7 strategies with WOMAC at 12 months: injection of platelet rich plasma (PRP), corticosteroids, mesenchymal stem cells (MSCs), hyaluronic acid, ozone, administration of nonsteroidal anti-inflammatory drugs with or without the association of physiotherapy. For treatment-specific effect size, a greater association with WOMAC decrease was found significantly for MSCs (mean difference, -28.0 [95% CrI, -32.9 to -22.4]) and PRP (mean difference, -19.9 [95% CrI, -24.1 to -15.8]). Rank probabilities among the treatments indicated that MSCs had a much higher probability (P = .91) of being the best treatment compared with other treatments, while PRP ranked as the second-best treatment (P = .89).

CONCLUSION

In this systematic review and network meta-analysis, the outcomes of treatments using MSCs and PRP for the management of knee osteoarthritis were associated with long-term improvements in pain and function. More high quality RCTs would be needed to confirm the efficiency of MSCs and PRP for the treatment of patients with knee osteoarthritis.

Adipose Tissue-Derived Mesenchymal Stem Cells as a Potential Restorative Treatment for Cartilage Defects: A PRISMA Review and Meta-Analysis

Cartilage defects are a predisposing factor for osteoarthritis. Conventional therapies are mostly palliative and there is an interest in developing newer therapies that target the disease’s progression. Mesenchymal stem cells (MSCs) have been suggested as a promising therapy to restore hyaline cartilage to cartilage defects, though the optimal cell source has remained under investigation. A PRISMA systematic review was conducted utilising five databases (MEDLINE, EMBASE, Cochrane Library, Scopus, Web of Science) which identified nineteen human studies that used adipose tissue-derived MSC (AMSC)-based therapies, including culture-expanded AMSCs and stromal vascular fraction, to treat cartilage defects. Clinical, imaging and histological outcomes, as well as other relevant details pertaining to cartilage regeneration, were extracted from each study. Pooled analysis revealed a significant improvement in WOMAC scores (mean difference: −25.52; 95%CI (−30.93, −20.10); p < 0.001), VAS scores (mean difference: −3.30; 95%CI (−3.72, −2.89); p < 0.001), KOOS scores and end point MOCART score (mean: 68.12; 95%CI (62.18, 74.05)), thus showing improvement. The studies in this review demonstrate the safety and efficacy of AMSC-based therapies for cartilage defects. Establishing standardised methods for MSC extraction and delivery, and performing studies with long follow-up should enable future high-quality research to provide the evidence needed to bring AMSC-based therapies into the market.

Does the Source of Mesenchymal Stem Cell Have an Effect in the Management of Osteoarthritis of the Knee? Meta-Analysis of Randomized Controlled Trials

STUDY DESIGN

Meta-analysis.

OBJECTIVES

To compare the efficacy and safety of bone marrow(BM)-derived mesenchymal stem cell(MSCs) and adipose-derived(AD) MSCs in the management of osteoarthritis of knee from randomized controlled trials(RCTs) available in the literature.

MATERIALS AND METHODS

We conducted electronic database searche from PubMed, Embase, and Cochrane Library till May 2020 for RCTs analyzing the efficacy and safety of MSCs in management of osteoarthritis of knee. Visual Analog Score(VAS) for Pain, Western Ontario McMaster Universities Osteoarthritis Index(WOMAC), Lysholm Knee Scale(Lysholm), Whole-Organ Magnetic Resonance Imaging Score(WORMS), Knee Osteoarthritis Outcome Score(KOOS), and adverse events were the outcomes analyzed. Analysis was performed in R platform using OpenMeta[Analyst] software.

RESULTS

Nineteen studies involving 811 patients were included for analysis. None of the studies compared the source of MSCs for osteoarthritis of knee and results were obtained by pooled data analysis of both sources. At 6 months, AD-MSCs showed significantly better VAS(P<0.001,P=0.069) and WOMAC(P=0.134,P=0.441) improvement than BM-MSCs, respectively, compared to controls. At 1 year, AD-MSCs outperformed BM-MSCs compared to their control in measures like WOMAC(P=0.007,P=0.150), KOOS(P<0.001;P=0.658), and WORMS(P<0.001,P=0.041), respectively. Similarly at 24 months, AD-MSCs showed significantly better Lysholm score(P=0.037) than BM-MSCs(P=0.807) although VAS improvement was better with BM-MSCs at 24 months(P<0.001). There were no significant adverse events with either of the MSCs compared to their controls.

CONCLUSION

Our analysis establishes the efficacy, safety, and superiority of AD-MSC transplantation, compared to BM-MSC, in the management of osteoarthritis of knee from available literature. Further RCTs are needed to evaluate them together with standardized doses.

Comparison of Minimally Invasive Procedures to Treat Knee Pain Secondary to Osteoarthritis: A Systematic Review and Meta-Analysis

PURPOSE

To review and indirectly compare the outcomes of minimally invasive therapies for the treatment of lower urinary tract symptoms secondary to benign prostatic hyperplasia.

MATERIALS AND METHODS

A literature search via Medline and Cochrane Central databases was completed for randomized control studies published between January 2000 to April 2020 for the following therapies: Rezum, Urolift, Aquablation, and prostate artery embolization (PAE). Data on the following variables were included: international Prostate Symptom Score (IPSS), maximum urinary flow rate (Qmax), quality of life (QoL), and post-void residual (PVR). Standard mean differences between treatments were compared through a meta-analysis using transurethral resection of the prostate (TURP) to assess differences in treatment effect.

RESULTS

No significant difference in outcomes between therapies were noted for IPSS at the 3-, 6-, and 12-month follow-ups. Although outcomes for rezum were only available out to 3 months, there were no consistently significant differences in outcomes when comparing Aquablation vs PAE vs Rezum. TURP PVR was significantly better than Urolift at 3-, 6-, and 12 months. No significant differences in minor or major AEs were noted.

CONCLUSION

Although significant differences in outcomes were limited, aquablation and PAE were the most durable at 12 months. PAE has been well studied on multiple randomized control trials with minimal adverse events while aquablation has limited high quality data and has been associated with bleeding-related complications.

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.

Mechanobiology-based physical therapy and rehabilitation after orthobiologic interventions: a narrative review

PURPOSE

This review aims to summarize the evidence for the role of mechanotherapies and rehabilitation in supporting the synergy between regeneration and repair after an orthobiologic intervention.

METHODS

A selective literature search was performed using Web of Science, OVID, and PubMed to review research articles that discuss the effects of combining mechanotherapy with various forms of regenerative medicine.

RESULTS

Various mechanotherapies can encourage the healing process for patients at different stages. Taping, bracing, cold water immersion, and extracorporeal shockwave therapy can be used throughout the duration of acute inflammatory response. The regulation of angiogenesis can be sustained with blood flow restriction and resistance training, whereas heat therapy and tissue loading during exercise are recommended in the remodeling phase.

CONCLUSION

Combining mechanotherapy with various forms of regenerative medicine has shown promise for improving treatment outcomes. However, further studies that reveal a greater volume of evidence are needed to support clinical decisions.

Attenuation of Knee Osteoarthritis Progression in Mice through Polarization of M2 Macrophages by Intra-Articular Transplantation of Non-Cultured Human Adipose-Derived Regenerative Cells

Adipose-derived regenerative cells (ADRCs) are non-cultured heterogeneous or mixed populations of cells obtained from adipose tissue by collagenase digestion. The injection of ADRCs have been tried clinically for the treatment of osteoarthritis (OA). The purpose of this study was to evaluate the effect of intra-articular transplantation of human ADRCs on OA progression in mice and the effect of ADRCs on macrophage polarization. In in vivo experiments, BALB/c-nu mice with knee OA received intra-articular transplantation of either phosphate buffered-saline or human ADRCs. OA progression was evaluated histologically and significantly attenuated in the ADRC group at both four and eight weeks postoperatively. The expression of OA-related proteins in the cartilage and macrophage-associated markers in the synovium were examined by immunohistochemistry. The numbers of MMP-13-, ADAMTS-5-, IL-1β-, IL-6- and iNOS-positive cells significantly decreased, and type II collagen- and CD206-positive cells were more frequently detected in the ADRC group compared with that in the control group. In vitro co-culture experiments showed that ADRCs induced macrophage polarization toward M2. The results of this study suggest that the intra-articular transplantation of human ADRCs could attenuate OA progression possibly by reducing catabolic factors in chondrocytes and modulating macrophage polarization.

Stromal Vascular Fraction for Osteoarthritis of the Knee Regenerative Engineering

Purpose

The knee joint is prone to osteoarthritis (OA) due to its anatomical position, and several reports have implicated the imbalance between catabolic and anabolic processes within the joint as the main culprit, thus leading to investigations towards attenuation of these inflammatory signals for OA treatment. In this review, we have explored clinical evidence supporting the use of stromal vascular fraction (SVF), known for its anti-inflammatory characteristics for the treatment of OA.

Methods

Searches were made on PubMed, PMC, and Google Scholar with the keywords “adipose fraction knee regeneration, and stromal vascular fraction knee regeneration, and limiting searches within 2017–2020.

Results

Frequently found interventions include cultured adipose-derived stem cells (ADSCs), SVF, and the micronized/microfragmented adipose tissue-stromal vascular fraction (MAT-SVF). Clinical data reported that joints treated with SVF provided a better quality of life to patients. Currently, MAT-SVF obtained and administered at the point of care is approved by the Food and Drug Administration (FDA), but more studies including manufacturing validation, safety, and proof of pharmacological activity are needed for SVF. The mechanism of action of MAT-SVF is also not fully understood. However, the current hypothesis indicates a direct adherence and integration with the degenerative host tissue, and/or trophic effects resulting from the secretome of constituent cells.

Conclusion

Our review of the literature on stromal vascular fraction and related therapy use has found evidence of efficacy in results. More research and clinical patient follow-up are needed to determine the proper place of these therapies in the treatment of osteoarthritis of the knee.

Lay Summary

Reports have implicated the increased inflammatory proteins within the joints as the main cause of osteoarthritis (OA). This has attracted interest towards addressing these inflammatory proteins as a way of treatment for OA. The concentrated cell-packed portion of the adipose product stromal vascular fraction (SVF) from liposuction or other methods possesses anti-inflammatory effects and has been acclaimed to heal OA. Thus, we searched for clinical evidence supporting their use, for OA treatment through examining the literature. Data from various hospitals support that joints treated with SVF provided a better quality of life to patients. Currently, there is at least one version of these products that are obtained and given back to patients during a single clinic visit, approved by the FDA.

Meta-Analysis of Adipose Tissue Derived Cell-Based Therapy for the Treatment of Knee Osteoarthritis

Osteoarthritis (OA) is a degenerative disorder associated with cartilage loss and is a leading cause of disability around the world. In old age, the capacity of cartilage to regenerate is diminished. With an aging population, the burden of OA is set to rise. Currently, there is no definitive treatment for OA. However, cell-based therapies derived from adipose tissue are promising. A PRISMA systematic review was conducted employing four databases (MEDLINE, EMBASE, Cochrane, Web of Science) to identify all clinical studies that utilized adipose tissue derived mesenchymal stem cells (AMSCs) or stromal vascular fraction (SVF) for the treatment of knee OA. Eighteen studies were included, which met the inclusion criteria. Meta-analyses were conducted on fourteen of these studies, which all documented WOMAC scores after the administration of AMSCs. Pooled analysis revealed that cell-based treatments definitively improve WOMAC scores, post treatment. These improvements increased with time. The studies in this meta-analysis have established the safety and efficacy of both AMSC therapy and SVF therapy for knee OA in old adults and show that they reduce pain and improve knee function in symptomatic knee OA suggesting that they may be effective therapies to improve mobility in an aging population.

Fresh autologous stromal tissue fraction for the treatment of knee osteoarthritis related pain and disability

Knee osteoarthritis (KOA) is a very common condition with multifactorial etiology leading to severe pain and disability in the adult population. Although KOA is considered a non-inflammatory arthritis, upregulation of inflammatory and catabolic pathways with increased production of proinflammatory cytokines leading to cartilage degradation and extracellular matrix degeneration has been reported. Intra-articular injection of fresh fat derived stromal vascular fraction (SVF) fraction has been proposed as a valid and alternative treatment for symptomatic KOA that guarantees mechanical support through viscosupplementation, anti-inflammatory, and anabolic action. We retrospectively reviewed a case series of 84 consecutive adult patients with KOA who underwent intra-articular injection of fresh fat derived SVF. Significant improvement in pain levels (NRS score decrease 3.5±1.1, p<0.001), WOMAC pain (-7.02±3.45 score change, p<0.001), WOMAC stiffness (-1.97±1.02, p<0.001), and ROM improvement (+17.13±5.22°, p<0.001). The only complication noted was knee joint swelling lasting for less than 7 days after the injection in 7% of the patients.

Emerging Biological Treatment Methods for Ankle Joint and Soft Tissue Conditions: Clinical Applications as Alternative or Adjuvant

In the past 2 decades, there has been a rapid expansion of clinical studies investigating the safety and efficacy of biological treatment methods for a wide range of diseases. These biological treatment methods increasingly are used in clinical practice based on limited available evidence. This article provides an overview of evidence on biological treatment methods for foot and ankle pathologies, including ankle osteoarthritis, osteochondral lesions of the talus, and Achilles tendinopathy.

Biofat grafts as an orthobiologic tool in osteoarthritis: An update and classification proposal

Among degenerative musculoskeletal disorders, osteoarthritis remains one of the main causes of pain and disability in the adult population. Current available alternatives to alleviate symptoms include conservative treatments such as physical therapy, anti-inflammatory drugs and an educational approach to lifestyle modification. The use of certain analgesics, such as opiates and corticosteroids offer short-term results but does not address the etiological source of pain and disability. In addition, prolonged use of such medications can cause additional complications. Therefore, the demand for regeneration of joint cartilage has led to an alternative approach called "orthobiologics". This alternative is based on cellular and molecular components capable of inducing and promoting tissue repair. Products derived from adipose tissue have been studied as an excellent source of orthobiologics in an attempt to promote joint cartilage repair. However, the lack of standardization regarding collection and processing protocols presents a challenge for the generalization of study results and determination of effectiveness. To the best of our knowledge, orthobiologics derived from fat have not yet been classified. Therefore, this manuscript proposes the HGS classification system which aims to describe certain parameters that are relevant to the quality of organic products regarding harvesting techniques (H), graft type (G), and number of centrifugations (S). The more parameters used would imply greater characterization and complexity of the evaluation of the biological product used. The HGS classification may provide a valuable contribution to the understanding of clinical procedures and research results, aiming to ultimately usher in a standardization of optimal practice.

Stromal Vascular Fraction and Amniotic Epithelial Cells: Preclinical and Clinical Relevance in Musculoskeletal Regenerative Medicine

Musculoskeletal regenerative medicine is mainly based on the use of cell therapy to heal damaged tissues such as bone, cartilage, and tendons. Throughout the years, different cell types have been employed for the treatment of musculoskeletal diseases, in particular, mesenchymal stem cells (MSCs) derived from bone marrow (BMSCs) and adipose tissue (ADSCs). Though the results of these literature studies have been encouraging, there are some limitations, especially on long-term results. Recently, some interest has shifted towards new cell types such as the stromal vascular fraction (SVF) and amniotic endothelial cells (AECs). The aim of the present literature review is to evaluate preclinical and clinical studies that used SVF and AECs for musculoskeletal tissue regeneration. Forty-eight preclinical and clinical studies, performed in the last 10 years, were identified. Both SVF and AECs, injected or implanted with or without scaffolds, were shown to be valid alternatives, and in some ways superior, to ADSCs and BMSCs, being able to differentiate towards osteogenic, chondrogenic, and tenogenic lineages, and to promote cell and tissue regenerative potential. The use of SVF and AECs could represent a new regenerative treatment in several musculoskeletal pathologies, solving the problem of cell expansion in vitro.

Mesenchymal stromal cell products for intra-articular knee injections for conservative management of osteoarthritis

Sports injuries and secondary joint problems, mainly of the knee, are common, especially in sports associated with high impact activities and/or torsional loading. The consequences can be career ending in elite athletes and reduce exercise activities in recreational people. Various cell products can be injected intra-articularly. First, fresh cellular mixtures can be prepared and injected in the same day, such as stromal vascular fraction of adipose tissue (SVF) and bone marrow concentrates (BMCs). Second, autologous mesenchymal stromal cells (MSCs) can be isolated from BMCs or SVF and, after several weeks of laboratory expansion, several millions of MSCs can be obtained for intra-articular injection. Finally, allogeneic MSCs from the bone marrow, adipose tissue or perinatal tissues of selected donors constitute an ‘off-the-shelf’ experimental treatment for injection delivery in patients with osteoarthritis of the knee. The perceived efficacy of all these products is based on the hypothesis of a paracrine mechanism of action: when living cells are delivered within the joint, they establish a molecular cross-talk with immune cells and local cell phenotypes, thereby modulating inflammation with subsequent modifications in the catabolic/degenerative milieu. Current clinical research examines whether injection delivery of MSCs translates into actual clinical benefits. Overall, clinical studies lack the quality needed to answer major research questions, including clinical and structural efficacy, optimal cell dose, and number of injections and specific protocol for cell delivery. Poor experimental designs are exacerbated by the diversity of patient phenotypes that hinder comparisons between treatments. Further understanding of disease pathology is paramount to develop potent function assays and understand whether the host tissue, the cell product or both should be primed before MSCs are injected intra-articularly.

Cryopreserved human adipose-derived stromal vascular fraction maintains fracture healing potential via angiogenesis and osteogenesis in an immunodeficient rat model

Background

Novel therapeutic strategies for the healing of nonunion, which has serious effects on the quality of life of patients, are needed. We evaluated the therapeutic effect of local transplantation of human stromal vascular fraction (SVF) cells on fracture healing in a rat non-healing fracture model and compared the effects between freshly isolated (F) and cryopreserved (C)-SVFs.

Methods

Non-healing fracture model was induced in the femur of female immunodeficient rats (F344/N Jcl rnu/rnu) with cauterizing periosteum. Immediately after the creation of non-healing fracture, rats received local transplantation of F and C-SVFs suspended in phosphate-buffered saline (PBS) or the same volume of PBS without cells using the same scaffold as a control group. During 8 weeks post-surgery, radiologic, histological, immunohistochemical, and biomechanical analyses were performed to evaluate fracture healing. The comparison of radiological results was performed with a chi-square test, and the multiple comparisons of immunohistochemical, histological, and biomechanical results among groups were made using a one-way analysis of variance. A probability value of 0.05 was considered to denote statistical significance.

Results

At week 8, in 60% of animals receiving F-SVF cells and in 50% of animals receiving C-SVF cells, the fracture radiologically healed with bone union whereas nonunion was observed in the control group. The healing potential was also confirmed by histological and biomechanical assessments. One of the mechanisms underlying healing involving intrinsic angiogenesis/osteogenesis was enhanced in F- and C-SVF groups compared with that in the control group. Human cell-derived vasculogenesis/osteogenesis, which was also confirmed in an in vitro differentiation assay, was also enhanced in the F- and C-SVF groups compared with that in the control groups and could be another mechanism for healing.

Conclusions

SVF cells can enhance bone healing and cryopreserved cells have almost equal potential as fresh cells. SVF cells can be used for improving nonunion bone fracture healing as an alternative to other mesenchymal stem cells and the effect of SVF cells can be maintained under cryopreservation.

Mesenchymal Stem Cells: A New Choice for Nonsurgical Treatment of OA? Results from a Bayesian Network Meta-Analysis

Objective

Osteoarthritis (OA) is the most common degenerative joint disease, causing joint pain, stiffness, and even disability. Guidelines recommend intra-articular injections as an alternative treatment to relieve OA symptoms for patients who demonstrate poor tolerability or compliance to oral administration of drugs. Mesenchymal stem cells (MSCs) are a potential treatment for of OA. We conducted this network meta-analysis to comprehensively compare the efficacy and safety between hyaluronic acid (HA), corticosteroids (GCs), platelet-rich plasma (PRP), and MSCs.

Design

Systematic review and Bayesian network meta-analysis. Data Sources. Relevant studies, published from January 2000 to January 2020, in the PubMed, Cochrane library, EMBASE, and CKNI databases.

Methods

Bayesian network and conventional meta-analyses were conducted. Pain relief, functional improvement, improvement in joint stiffness, and risk of adverse effects (AEs) were assessed.

Results

Twenty-five articles with 4642 patients were included. Overall, MSC therapy was the most effective treatment for pain relief (standardized mean difference compared with placebo = 3.61, 95% CI [1.87 to 5.35]). Both MSC and PRP therapies improved every symptom of OA effectively and have an advantage over HA and GCs which are recommended by guidelines. MSCs, PRP, HA, and GCs are tolerated well for patients in long-term treatment of OA compared with placebo.

Conclusions

The results show that MSCs relieve pain, stiffness, and dysfunction due to OA better than PRP, HA, and GCs and are not statistically correlated with greater safety concerns. More high-quality trials are needed to reconfirm the findings of this study, however, standardization of preparation of MSCs and PRP should be investigated in the future.

Osteoarthritis year in review 2020: imaging

This narrative "Year in Review" highlights a selection of articles published between January 2019 and April 2020, to be presented at the OARSI World Congress 2020 within the field of osteoarthritis (OA) imaging. Articles were obtained from a PubMed search covering the above period, utilizing a variety of relevant search terms. We then selected original and review studies on OA-related imaging in humans, particularly those with direct clinical relevance, with a focus on the knee. Topics selected encompassed clinically relevant models of early OA, particularly imaging applications on cruciate ligament rupture, as these are of direct clinical interest and provide potential opportunity to evaluate preventive therapy. Further, imaging applications on structural modification of articular tissues in patients with established OA, by non-pharmacological, pharmacological and surgical interventions are summarized. Finally, novel deep learning approaches to imaging are reviewed, as these facilitate implementation and scaling of quantitative imaging application in clinical trials and clinical practice. Methodological or observational studies outside these key focus areas were not included. Studies focused on biology, biomechanics, biomarkers, genetics and epigenetics, and clinical studies that did not contain an imaging component are covered in other articles within the OARSI "Year in Review" series. In conclusion, exciting progress has been made in clinically validating human models of early OA, and the field of automated articular tissue segmentation. Most importantly though, it has been shown that structure modification of articular cartilage is possible, and future research should focus on the translation of these structural findings to clinical benefit.

Assessment of safety and efficacy of intra-articular injection of stromal vascular fraction for the treatment of knee osteoarthritis-a systematic review

PURPOSE

Stromal vascular fraction (SVF) as an injectable regenerative therapy for knee osteoarthritis (OA) has gained recent popularity. However, there is no clear consensus on the outcomes of such treatment. We systematically reviewed available evidence on the use of SVF injection in the treatment of knee OA.

METHODS

The study was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, with keyword search in PubMed, Scopus, and the Cochrane Library Database and related article search in Google Scholar. Clinical studies demonstrating effects of SVF in knee OA and published in English literature were included. Risk of bias assessment was done with modified Coleman Methodology Scoring (CMS).

RESULTS

Eleven studies (9 prospective, 2 retrospective) that contributed to 290 knees in 200 patients were included. Two studies that contributed to 3718 knee injections were excluded from pooled analysis and were scrutinized separately. Majority of patients reported improvement in pain, range of motion (ROM), functional rating, six metre walking distance, and functional outcome scores. There was no major donor-site morbidity. There was only one reported case of knee joint infection and no case of tumour formation in relation to SVF injection.

DISCUSSION

Intra-articular injection of SVF can be a simple, affordable, and minimally invasive treatment that could serve as an interim option for patients who failed other conservative and arthroscopic options.

CONCLUSION

Intra-articular injection of SVF is a safe and effective technique for the management of knee OA. However, comparative Level I studies are needed to support the use of adjuvants with SVF and also to compare the use of SVF (with or without adjuvants) with ADMSCs, PRP, and bone marrow concentrate.

Editorial Commentary: Intra-Articular Injections for Painful Knee Osteoarthritis: What Is the Current Treatment Paradigm?

Intra-articular corticosteroids are useful for acute and short-term pain relief, whereas hyaluronic acid is useful for a longer-term treatment effect for patients with knee osteoarthritis. More rigorous research using homogeneous preparations and techniques and randomizing larger numbers of knee osteoarthritis patients are warranted before recommending any wider acceptance of platelet-rich plasma and stem cell therapies. This is of utmost importance, especially with several new injectables such as anti-nerve growth factor antibodies, Wnt pathway inhibitors, and capsaicin showing promise to enter the market soon.

Intra-Articular Injections of Hyaluronic Acid or Steroids Associated With Better Outcomes Than Platelet-Rich Plasma, Adipose Mesenchymal Stromal Cells, or Placebo in Knee Osteoarthritis: A Network Meta-analysis

PURPOSE

To evaluate the clinical effects of hyaluronic acid (HA), steroids, platelet-rich plasma (PRP), or adipose mesenchymal stromal cell (MSC) injections in the treatment of knee osteoarthritis (OA).

METHODS

Randomized controlled trials with OA of the knee that compared HA, steroids, PRP, adipose MSC, or their combination with placebo or in head-to-head combination were identified from the MEDLINE, EMBASE, Cochrane Library, Web of Science, and SCOPUS databases up to June 30, 2019. We performed a network meta-analysis of the relevant literature to determine whether there was benefit from HA, steroids, PRP, or adipose MSC treatment as compared with placebo.

RESULTS

A total of 43 trials covering 5554 patients were included. Steroids were ranked most likely to be effective for the management of pain or function, with adipose MSC and multiple PRP appearing least likely to be effective. Although no significant difference was observed among the 6 interventions, except for single PRP with respect to adverse effects, steroids and HA exhibited a lower rate of AEs compared with the placebo. In view of severe adverse effects, only single PRP was superior to placebo. Direct pairwise meta-analysis for pain relief showed that HA was superior to placebo or single PRP, but steroids had a significantly worse effect than single PRP. In addition, direct pairwise meta-analysis for adverse effects favored steroids in comparison to HA.

CONCLUSIONS

The ranking statistics like surface under the cumulative ranking curve values of our network meta-analysis support the use of steroids and HA for appropriate patients with knee OA. For pain relief and AEs, steroids are most likely the best treatment, followed by HA. Single PRP, multiple PRP, and adipose MSC interventions do not result in a relevant reduction of joint pain nor improvement of joint function compared with placebo. However, treatment effect differences were small and potentially not clinically meaningful, indicating that other factors, such as cost and patient preferences, may be more important in patients with knee OA.

LEVEL OF EVIDENCE

meta-analysis of non-homogenous randomized controlled trials, Level II.

Editorial Commentary: Stem Cell Treatment in Knee Osteoarthritis: What for? Pain Management or Cartilage Regeneration?

The efficacy of mesenchymal stem cells regarding clinical outcomes and cartilage regeneration in knee osteoarthritis remains unclear; however, their theoretical role in multilineage cellular differentiation and immunomodulation of the arthritic cascade has been investigated. Several studies have reported that the use of stem cell therapy for knee osteoarthritis helps in pain improvement, but its effect on cartilage regeneration has not yet been explored. Moreover, numerous studies have reported high heterogeneity in the cell sources, as well as methods of culture expansion or cell concentration, and differences in delivery methods, assessment tools, and concomitant surgical procedures, which could affect the clinical outcomes or evaluation of cartilage regeneration potency. Furthermore, future studies are warranted to examine these factors in detail to interpret the results of mesenchymal stem cell treatment for knee osteoarthritis.

Intra-Articular Mesenchymal Stromal Cell Injections Are No Different From Placebo in the Treatment of Knee Osteoarthritis: A Systematic Review and Meta-analysis of Randomized Controlled Trials

PURPOSE

To evaluate the efficacy and safety of intra-articular mesenchymal stromal cells (MSCs) injections for knee osteoarthritis (OA) treatment.

METHODS

We performed a systematic literature search in PubMed, Embase, Scopus, and the Cochrane Library through April 2020 to identify level I randomized controlled trials (RCTs) that evaluated the clinical efficacy of MSCs versus control treatments for knee OA. Outcomes were analyzed on an intention-to-treat basis with random-effects models.

RESULTS

A total of 13 RCTs were included in the meta-analysis. Compared with placebo, there was no significant difference in VAS for pain (mean difference [MD] 1.62, 95% confidence interval [CI -0.60 to 3.85), WOMAC pain score (MD 1.88, 95% CI -0.21 to 3.98), WOMAC function score (MD -0.67, 95% CI -6.54 to 5.19), or WOMAC stiffness score (MD 0.64, 95% CI -0.86 to 2.14) for MSCs. Moreover, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the minimum clinically important difference (MCID). Additionally, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and placebo groups for VAS for pain (relative risk [RR] 0.93, 95% CI 0.55 to 1.57) or WOMAC total score (RR 0.40, 95% CI 0.13 to 1.21). Compared with hyaluronic acid (HA), MSC injection was associated with significantly better improvement in VAS for pain (MD 2.00, 95% CI 0.94 to 3.07), WOMAC pain score (MD 4.58, 95% CI 0.49 to 8.67), WOMAC total score (MD 14.86, 95% CI 10.59 to 19.13), and WOMAC stiffness score (MD 1.85, 95% CI 0.02 to 3.69). However, the smallest treatment effect of VAS for pain, WOMAC pain score, WOMAC function score, and WOMAC stiffness score did not exceed the MCID. Moreover, there was no significant difference in percentage of patients crossing the MCID threshold between MSC and HA groups for WOMAC total score (RR 0.57, 95% CI 0.21 to 1.55). We also found that MSCs did not increase adverse events compared with HA and placebo.

CONCLUSIONS

Intra-articular MSC injection was not found to be superior to placebo in pain relief and functional improvement for patients with symptomatic knee OA. However, additional direct testing and combination trials of different type of cells, doses, and number of injections of MSCs are required to further enhance clinical decision making for people with symptomatic knee OA.

LEVEL OF EVIDENCE

I, meta-analysis of level I studies.

Simple and Rapid Non-Enzymatic Procedure Allows the Isolation of Structurally Preserved Connective Tissue Micro-Fragments Enriched with SVF

The stromal vascular fraction (SVF) consists of a heterogeneous population of stem and stromal cells, generally obtained from adipose tissue by enzymatic digestion. For human cell-based therapies, mechanical process methods to obtain SVF represent an advantageous approach because they have fewer regulatory restrictions for their clinical use. The aim of this study was to characterize a novel commercial system for obtaining SVF from adipose tissue by a mechanical approach without substantial manipulations. Lipoaspirate samples collected from 27 informed patients were processed by a simple and fast mechanical system (by means of Hy-Tissue SVF). The Hy-Tissue SVF product contained a free cell fraction and micro-fragments of stromal connective tissue. The enzymatic digestion of the micro-fragments increased the yield of free cells (3.2 times) and CFU-F (2.4 times). Additionally, 10% of free cells from SVF were positive for CD34+, suggesting the presence of endothelial cells, pericytes, and potential adipose-derived stem cells (ADSC). Moreover, the SVF cells were able to proliferate and differentiate in vitro toward adipocytes, osteocytes, and chondrocytes. The immunophenotypic analysis of expanded cells showed positivity for typical mesenchymal stem cell markers. The Hy-Tissue SVF system allows the isolation of stromal vascular fraction, making this product of potential interest in regenerative medicine.

Mesenchymal Stem Cell Implantation in Knee Osteoarthritis: Midterm Outcomes and Survival Analysis in 467 Patients

Background

A cell-based tissue engineering approach that uses mesenchymal stem cells (MSCs) has addressed the issue of articular cartilage repair in knees with osteoarthritis (OA).

Purpose

To evaluate the midterm outcomes, analyze the survival rates, and identify the factors affecting the survival rate of MSC implantation to treat knee OA.

Study Design

Case series; Level of evidence, 4.

Methods

We retrospectively evaluated 467 patients (483 knees) who underwent MSC implantation on a fibrin glue scaffold for knee OA with a minimum 5-year follow-up. Clinical outcomes were determined based on the International Knee Documentation Committee (IKDC) and Tegner activity scale results measured preoperatively and during follow-up. Standard radiographs were evaluated using Kellgren-Lawrence grading. Statistical analyses were performed to determine the survival rate and the effect of different factors on the clinical outcomes.

Results

The mean IKDC scores (baseline, 39.2 ± 7.2; 1 year, 66.6 ± 9.6; 3 years, 67.2 ± 9.9; 5 years, 66.1 ± 9.7; 9 years, 62.8 ± 8.5) and Tegner scores (baseline, 2.3 ± 1.0; 1 year, 3.4 ± 0.9; 3 years, 3.5 ± 0.9; 5 years, 3.4 ± 0.9; 9 years, 3.2 ± 0.9) were significantly improved until 3 years postoperatively and gradually decreased from 3- to 9-year follow-up (P < .05 for all, except for Tegner score at 5 years vs 1 year [P = .237]). Gradual deterioration of radiological outcomes according to the Kellgren-Lawrence grade was found during follow-up. Survival rates based on either a decrease in IKDC or an advancement of radiographic OA with Kellgren-Lawrence scores were 99.8%, 94.5%, and 74.5% at 5, 7, and 9 years, respectively. Based on multivariate analyses, older age and the presence of bipolar kissing lesion were associated with significantly worse outcomes (P = .002 and .013, respectively), and a larger number of MSCs was associated with significantly better outcomes (P < .001) after MSC implantation.

Conclusion

MSC implantation provided encouraging outcomes with acceptable duration of symptom relief at midterm follow-up in patients with early knee OA. Patient age, presence of bipolar kissing lesion, and number of MSCs were independent factors associated with failure of MSC implantation.

Autologous adipose stem cell therapy for knee osteoarthritis: where are we now?

Introduction: The purpose of this study was to evaluate the efficacy and safety of adipose-derived stem cell (ADSC) or stromal vascular fraction (SVF) injections for knee osteoarthritis (OA) treatment by analyzing all randomized controlled trials dealing with this topic. Materials and methods: The following search terms were used in PUBMED, EMBASE, Scopus, and the Cochrane Library Database on 14 November 2019: 'adipose derived stem cell' OR 'stromal vascular fraction' OR 'SVF' OR 'multipotent mesenchymal stromal cells' OR 'stem cell' OR 'derived stem cell' OR 'autologous' AND 'knee' OR 'osteoarthritis' OR 'chondral defect' OR 'randomized' OR 'controlled trial.' No time limit was given to publication date. We included randomized controlled trials (RCTs) based on the following criteria: (1) English studies; (2) patient population diagnosed with knee OA and treated with ADSCs or SVF injections; (3) comparison group treated with placebo, surgery, or adjuvant injections, such as platelet rich-plasma or hyaluronic acid. Results: Intra-articular injections of adipose stem cell therapy in the form of ADSC or SVF is a safe procedure for the treatment of knee OA, with good clinical and radiological outcomes in the early follow-up period (12-24 months). In addition, treatment with fat-derived cells showed a very low complication rate (16.15%) of which all were considered to be minor. Conclusions: ADSCs and SVF seem to produce promising good to excellent clinical results for the treatment of knee OA. However, the length and modalities of follow-up in the different conditions are extremely variable. Nevertheless, it appears that the use of adipose-derived stem cells is associated with clinical and radiological improvements and minimal complication rates. To avoid bias deriving from the use of biological adjuvants or surgical procedures, randomized controlled trials comparing ADSCs or SVF and other treatments (for example, platelet rich-plasma or hyaluronic acid injections) should be performed.

Biological strategies for osteoarthritis: from early diagnosis to treatment

PURPOSE

To provide an updated review of the literature on the use of orthobiologics as a potential treatment option to alleviate symptoms associated with osteoarthritis (OA), slow the progression of the disease, and aid in cartilage regeneration.

METHODS

A comprehensive review of the literature was performed to identify basic science and clinical studies examining the role of orthobiologics in the diagnosis and management of osteoarthritis.

RESULTS

Certain molecules (such as interleukin-6 (IL-6), interleukin-8 (IL-8), matrix metalloproteinase (MMPs), cartilage oligomeric matrix protein (COMP), and tumor necrosis factor (TNF), microRNAs, growth differentiation factor 11 (GDF-11)) have been recognized as biomarkers that are implicated in the pathogenesis and progression of degenerative joint disease (DJD). These biomarkers have been used to develop newer diagnostic applications and targeted biologic therapies for DJD. Local injection therapy with biologic agents such as platelet-rich plasma or stem cell-based preparations has been associated with significant improvement in joint pain and function in patients with OA and has increased in popularity during the last decade. The combination of PRP with kartogenin or TGF-b3 may also enhance its biologic effect. The mesenchymal stem cell secretome has been recognized as a potential target for the development of OA therapies due to its role in mediating the chondroprotective effects of these cells. Recent experiments have also suggested the modification of gut microbiome as a newer method to prevent OA or alter the progression of the disease.

CONCLUSIONS

The application of orthobiologics for the diagnosis and treatment of DJD is a rapidly evolving field that will continue to expand. The identification of OA-specific and joint-specific biomarker molecules for early diagnosis of OA would be extremely useful for the development of preventive and therapeutic protocols. Local injection therapies with HA, PRP, BMAC, and other stem cell-based preparations are currently being used to improve pain and function in patients with early OA or those with progressed disease who are not surgical candidates. Although the clinical outcomes of these therapies seem to be promising in clinical studies, future research will determine the true role of orthobiologic applications in the field of DJS.

Treatment of Grade 3 and 4 Osteoarthritis with Intraoperatively Separated Adipose Tissue-Derived Stromal Vascular Fraction: A Comparative Case Series

Osteoarthritis (OA) is the most common form of arthritis of the joints. The stromal vascular fraction (SVF) is a regenerative cell population that can be isolated from adipose tissue. It is the immunomodulatory properties of the stromal vascular fraction that make it a promising candidate for the regenerative treatment of OA. Patients with grade 3 and 4 osteoarthritis were treated with the stromal vascular fraction with and without platelet-rich plasma (PRP) and followed up on their Knee Injury and Osteoarthritis Outcome Score (KOOS) score for 12 months, with MRI and subjective evaluation of the procedure. Magnetic resonance imaging (MRI) revealed a widening of the joint space, a restructuring of the cartilage, and an alleviation of effusions in the treated joints. In three of the four treatment groups, a substantial improvement of the KOOS scores was documented at the 12-month follow-up time point. According to the subjective evaluation, 67% of the patients were satisfied or very satisfied with the procedure and would recommend it to others. No serious adverse events or unwanted side effects related to the SVF treatment were observed or reported. Prior to an invasive artificial joint replacement, the treatment of arthritic knee joints with the intraarticular injection of autologous adipose tissue-derived SVF should be considered a regenerative treatment option.

Exosomes From Adipose-Derived Stem Cells: The Emerging Roles and Applications in Tissue Regeneration of Plastic and Cosmetic Surgery

Adipose-derived stem cells (ASCs) are an important stem cell type separated from adipose tissue, with the properties of multilineage differentiation, easy availability, high proliferation potential, and self-renewal. Exosomes are novel frontiers of intercellular communication regulating the biological behaviors of cells, such as angiogenesis, immune modulation, proliferation, and migration. ASC-derived exosomes (ASC-exos) are important components released by ASCs paracrine, possessing multiple biological activities. Tissue regeneration requires coordinated “vital networks” of multiple growth factors, proteases, progenitors, and immune cells producing inflammatory cytokines. Recently, as cell-to-cell messengers, ASC-exos have received much attention for the fact that they are important paracrine mediators contributing to their suitability for tissue regeneration. ASC-exos, with distinct properties by encapsulating various types of bioactive cargoes, are endowed with great application potential in tissue regeneration, mechanically via the migration and proliferation of repair cells, facilitation of the neovascularization, and other specific functions in different tissues. Here, this article elucidated the research progress of ASC-exos about tissue regeneration in plastic and cosmetic surgery, including skin anti-aging therapy, dermatitis improvement, wound healing, scar removal, flap transplantation, bone tissue repair and regeneration, obesity prevention, fat grafting, breast cancer, and breast reconstruction. Deciphering the biological properties of ASC-exos will provide further insights for exploring novel therapeutic strategies of tissue regeneration in plastic and cosmetic surgery.

Development and Prospect of Intra-Articular Injection in the Treatment of Osteoarthritis: A Review

Osteoarthritis (OA) is a common degenerative disease that affects the vast majority of the elderly and may eventually embark on the road of the total knee arthroplasty (TKA), although controversy still exists in the medical community about the best therapies for osteoarthritis. Compared with physical therapy, oral analgesics and other non-operative treatments, intra-articular injection is more safe and effective. Moreover, intra-articular injection is much less invasive and has fewer adverse reactions than surgical treatment. This article reviews mechanism, benefits and adverse reactions of corticosteroids (CS), hyaluronic acid (HA), platelet-rich plasma (PRP), mesenchymal stem cell (MSCs), stromal vascular fraction (SVF) and other new therapies (for example: gene therapy). The application prospect of intra-articular injection was analyzed according to the recent progress in drug research.

Deep Learning for Hierarchical Severity Staging of Anterior Cruciate Ligament Injuries from MRI

Purpose

To evaluate the diagnostic utility of two convolutional neural networks (CNNs) for severity staging of anterior cruciate ligament (ACL) injuries.

Materials and Methods

In this retrospective study, 1243 knee MR images (1008 intact, 18 partially torn, 77 fully torn, and 140 reconstructed ACLs) from 224 patients (mean age, 47 years ± 14 [standard deviation]; 54% women) were analyzed. The MRI examinations were performed between 2011 and 2014. A modified scoring metric was used. Classification of ACL injuries using deep learning involved use of two types of CNN, one with three-dimensional (3D) and the other with two-dimensional (2D) convolutional kernels. Performance metrics included sensitivity, specificity, weighted Cohen κ, and overall accuracy, and the McNemar test was used to compare the performance of the CNNs.

Results

The overall accuracies for ACL injury classification using the 3D CNN and 2D CNN were 89% (225 of 254) and 92% (233 of 254), respectively (P = .27), and both CNNs had a weighted Cohen κ of 0.83. The 2D CNN and 3D CNN performed similarly in classifying intact ACLs (2D CNN, sensitivity of 93% [188 of 203] and specificity of 90% [46 of 51] vs 3D CNN, sensitivity of 89% [180 of 203] and specificity of 88% [45 of 51]). Classification of full tears by both networks was also comparable (2D CNN, sensitivity of 82% [14 of 17] and specificity of 94% [222 of 237] vs 3D CNN, sensitivity of 76% [13 of 17] and specificity of 100% [236 of 237]). The 2D CNN classified all reconstructed ACLs correctly.

Conclusion

Two-dimensional and 3D CNNs applied to ACL lesion classification had high sensitivity and specificity, suggesting that these networks could be used to help nonexperts grade ACL injuries. Supplemental material is available for this article. © RSNA, 2020.

Autologous Mesenchymal Stem Cell Treatment is Consistently Effective for the Treatment of Knee Osteoarthritis: The Results of a Systematic Review of Treatment and Comparison to a Placebo Group

Background: Numerous studies have used autologous mesenchymal stem cell injections (AMSCI) to treat osteoarthritis. We hypothesized that AMSCI is an effective osteoarthritis treatment with increasing efficacy at higher doses. Methods: We conducted a PubMed search for human clinical studies using AMSCI for the treatment of osteoarthritis (OA) and a second search for placebo arms of injectate OA treatment. Inclusion criteria included treatment outcomes ratings both pre-treatment and at least 6 months post-treatment. Results: 45 AMSCI cohorts from 34 studies met criteria. All AMSCI cohorts showed improvement at mean 15.3 months post-treatment. Mean WOMAC and VAS scores improved at 6-months and at final follow-up (p < 0.0001 for all). Scores > 2 years were also significant (WOMAC p = 0.001/VAS p = 0.004). Results greatly exceeded the minimal clinically important difference (MCID) at each time point. AMSCI improvement also substantially exceeded previously published 6-month placebo-treatment improvement. No dose-response relationship was seen. AMSCI cohorts showed continuing improvement ≥ 6 months, and continued upward at one year. Placebo scores were already trending downward by 6 months. Conclusions: AMSCI is a consistently significantly effective treatment for osteoarthritis. It should no longer be stated that data is insufficient to establish AMSCI efficacy for OA. Given its excellent safety profile, AMSCI should be widely used for the treatment of osteoarthritis.

Evaluation of cartilage biomechanics and knee joint microenvironment after different cell-based treatments in a sheep model of early osteoarthritis

PURPOSE

Aiming to prevent cartilage damage during early osteoarthritis (OA), the therapeutic challenge is to restore and maintain the physiological and functional properties of such a tissue with minimally invasive therapeutic strategies.

METHODS

Accordingly, an in vivo model of early OA in sheep was here treated through three different cell therapies (culture expanded ADSCs, SVF, and culture expanded AECs) thus to preserve the joint surface from the progression of the pathology. Three months after the treatment injections, their performance was assessed through mechanical automated mapping (Young's modulus and cartilage thickness), gross evaluation of articular surfaces, and biochemical analysis of the synovial fluid.

RESULTS

No severe degeneration was observed after three months from OA induction. Cartilage mechanical properties were crucial to identify early degeneration. All the treatments improved the macroscopic cartilage surface aspect and reduced pro-inflammatory cytokines in the synovial fluid. Among the three treatments, SVF highlighted the best performance while ADSCs the worst.

CONCLUSION

Despite that the evaluated experimental time is an early follow-up and, thus, longer trial is mandatory to properly assess treatments effectiveness, the proposed multidisciplinary approach allowed to obtain preliminary, but also crucial, results concerning the reduction in OA signs on cartilage properties, in osteophyte development and in all the inflammatory markers.

Evidence on ankle injections for osteochondral lesions and osteoarthritis: a systematic review and meta-analysis

PURPOSE

To evaluate the evidence supporting safety and effectiveness of intra-articular injective treatments for ankle lesions ranging from osteochondral lesions of the talus (OLT) to osteoarthritis (OA).

METHODS

A systematic review and a meta-analysis were performed on PubMed, Embase, and Cochrane Library in March 2020. Safety was evaluated through the reported side effects and effectiveness through the scores used. The quality of the studies was assessed using the Cochrane Collaboration Risk of Bias 2.0 tool and the Downs and Black checklist. For each outcome, the quality of evidence was graded according to GRADE guidelines.

RESULTS

Twenty-four studies (21 for OA, 3 for OLT) were included on hyaluronic acid (HA), platelet-rich plasma (PRP), saline, methylprednisolone, botulinum toxin type A (BoNT-A), mesenchymal stem cells (MSCs), and prolotherapy. No severe adverse events were reported. For OLT, a comparison was possible between HA and PRP showing no significant difference. For ankle OA, a significant difference favouring HA versus saline was documented at six months (p < 0.001). The GRADE level of evidence was very low.

CONCLUSION

This meta-analysis supports the safety of intra-articular treatment for ankle OA and OLT, while only a very low evidence supports the efficacy of HA in terms of better results versus placebo for the treatment of ankle OA, and other conclusions are hindered by the scarcity of the available literature. This urges further and stronger trials to specifically investigate potential and limitations of these different injective approaches for the treatment of OLT and ankle OA.

Mesenchymal Stromal Cell-Based Therapy-An Alternative to Arthroplasty for the Treatment of Osteoarthritis? A State of the Art Review of Clinical Trials

Osteoarthritis (OA) is the most common degenerative joint disorder worldwide and to date no regenerative treatment has been established in clinical practice. This review evaluates the current literature on the clinical translation of mesenchymal stromal cell (MSC)-based therapy in OA management with a focus on safety, outcomes and procedural specifics. PubMed, Cochrane Library and clinicaltrials.gov were searched for clinical studies using MSCs for OA treatment. 290 articles were initially identified and 42 articles of interest, including a total of 1325 patients, remained for further examination. Most of the included studies used adipose tissue-derived MSCs or bone-marrow-derived MSCs to treat patients suffering from knee OA. MSC-based therapy for knee OA appears to be safe and presumably effective in selected parameters. Yet, a direct comparison between studies was difficult due to a pronounced variance regarding methodology, assessed outcomes and evidence levels. Intensive scientific engagement is needed to identify the most effective source and dosage of MSCs for OA treatment in the future. Consent on outcome measures has to be reached and eventually patient sub-populations need to be identified that will profit most from MSC-based treatment for OA.