Two-year clinical outcomes of autologous microfragmented adipose tissue in elderly patients with knee osteoarthritis: a multi-centric, international study

Impaired Remodeling of White Adipose Tissue in Obesity and Aging: From Defective Adipogenesis to Adipose Organ Dysfunction

The adipose organ adapts and responds to internal and environmental stimuli by remodeling both its cellular and extracellular components. Under conditions of energy surplus, the subcutaneous white adipose tissue (WAT) is capable of expanding through the enlargement of existing adipocytes (hypertrophy), followed by de novo adipogenesis (hyperplasia), which is impaired in hypertrophic obesity. However, an impaired hyperplastic response may result from various defects in adipogenesis, leading to different WAT features and metabolic consequences, as discussed here by reviewing the results of the studies in animal models with either overexpression or knockdown of the main molecular regulators of the two steps of the adipogenesis process. Moreover, impaired WAT remodeling with aging has been associated with various age-related conditions and reduced lifespan expectancy. Here, we delve into the latest advancements in comprehending the molecular and cellular processes underlying age-related changes in WAT function, their involvement in common aging pathologies, and their potential as therapeutic targets to influence both the health of elderly people and longevity. Overall, this review aims to encourage research on the mechanisms of WAT maladaptation common to conditions of both excessive and insufficient fat tissue. The goal is to devise adipocyte-targeted therapies that are effective against both obesity- and age-related disorders.

Intra-Articular Application of Autologous, Fat-Derived Orthobiologics in the Treatment of Knee Osteoarthritis: A Systematic Review

The aim of this study was to review the current literature regarding the effects of intra-articularly applied, fat-derived orthobiologics (FDO) in the treatment of primary knee osteoarthritis over a mid-term follow-up period. A systematic literature search was conducted on the online databases of Scopus, PubMed, Ovid MEDLINE, and Cochrane Library. Studies investigating intra-articularly applied FDO with a minimum number of 10 knee osteoarthritis patients, a follow-up period of at least 2 years, and at least 1 reported functional parameter (pain level or Patient-Reported Outcome Measures) were included. Exclusion criteria encompassed focal chondral defects and techniques including additional arthroscopic bone marrow stimulation. In 28 of 29 studies, FDO showed a subjective improvement in symptoms (pain and Patient-Reported Outcome Measures) up to a maximum follow-up of 7.2 years. Radiographic cartilage regeneration up to 3 years postoperatively, as well as macroscopic cartilage regeneration investigated via second-look arthroscopy, may corroborate the favorable clinical findings in patients with knee osteoarthritis. The methodological heterogeneity in FDO treatments leads to variations in cell composition and represents a limitation in the current state of knowledge. However, this systematic review suggests that FDO injection leads to beneficial mid-term results including symptom reduction and preservation of the affected joint in knee osteoarthritis patients.

Micro-Fragmented Adipose Tissue Demonstrates Comparable Clinical Efficacy to Other Orthobiologic Injections in Treating Symptomatic Knee Osteoarthritis: A Systematic Review of Level I to IV Clinical Studies

PURPOSE

To perform a systematic review of clinical outcomes in patients who underwent treatment with micro-fragmented aspirated tissue for symptoms of knee osteoarthritis.

METHODS

Medline, Embase, Scopus, and Google Scholar were screened for studies from 2000 to 2023. Risk of bias (ROB) was assessed using the Cochrane Collaboration's tools and the Risk Of Bias In Non-randomised Studies-of Interventions tool. Study quality was assessed with the modified Coleman Methodology Score and Methodological Index for Non-Randomized Studies score. Heterogeneity was assessed using χ2 and I2 statistics.

RESULTS

Twenty-one studies were included. One study had a high ROB, 1 had a critical ROB, 3 had serious ROB, and 16 had a moderate ROB. The mean Coleman score was 58, demonstrating fair study quality; the Methodological Index for Non-Randomized Studies score had a mean value of 13, indicating overall fair quality. Best evidence synthesis revealed moderate evidence. The visual analog scale score improved from 5.2 to 3.2 at 6 and 12 months. Knee injury and Osteoarthritis Outcome Score (KOOS) activities of daily living subscore improved from 58.8 to 70.2 at 6 months and 67.5 at 12 months. KOOS pain subscore improved from 54.3 to 70.2 at 6 months and 72.4 at 12 months. KOOS quality of life subscore improved from 33.1 to 43.6 at 6 months and 42.9 at 12 months. KOOS sports subscore improved from 23.7 to 43.6 at 6 months and 57.4 at 12 months. KOOS symptoms subscore improved from 55.3 to 70.1 at 6 months and 67.9 at 12 months. The Western Ontario and McMaster Universities Osteoarthritis Index score steadily increased from 61.8 at baseline to 78.4 at 12 months.

CONCLUSIONS

micro-fragmented aspirated tissue injection therapy for the treatment of symptomatic knee osteoarthritis is effective and improves pain and functional outcomes. Moderate study quality combined with a moderate risk of bias, moderate certainty of evidence, and moderate best synthesis evidence reduces external validity. Therefore, the results should be interpreted with a degree of caution.

LEVEL OF EVIDENCE

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

A Gender-Bias-Mitigated, Data-Driven Precision Medicine System to Assist in the Selection of Biological Treatments of Grade 3 and 4 Knee Osteoarthritis: Development and Preliminary Validation of precisionKNEE

Objective To identify key variables predictive of patient responses to microfragmented adipose tissue (MFAT) treatment in knee osteoarthritis (KOA) and evaluate its potential to delay or mitigate the need for total knee replacement (TKR). Methods We utilised a dataset comprising 329 patients treated with MFAT for KOA, incorporating variables such as gender, age, BMI, arthritic aetiology, radiological grade, and Oxford Knee Scores (OKS) pre- and post-treatment. We employed random forest regressors for model training and testing, with gender bias mitigation and outlier detection to enhance prediction accuracy. Model performance was assessed through root mean squared error (RMSE) and mean absolute error (MAE), with further validation in a TKR-suitable patient subset. Results The model achieved a test RMSE of 6.72 and an MAE of 5.38, reflecting moderate predictive accuracy across the patient cohort. Stratification by gender revealed no statistically significant differences between actual and predicted OKS improvements (p-values: males = 0.93, females = 0.92). For the subset of patients suitable for TKR, the model presented an increased RMSE of 9.77 and MAE of 7.81, indicating reduced accuracy in this group. The decision tree analysis identified pre-operative OKS, radiological grade, and gender as significant predictors of post-treatment outcomes, with pre-operative OKS being the most critical determinant. Patients with lower pre-operative OKS showed varying responses based on radiological severity and gender, suggesting a nuanced interaction between these factors in determining treatment efficacy. Conclusion This study highlights the potential of MFAT as a non-surgical alternative for KOA treatment, emphasising the importance of personalised patient assessments. While promising, the predictive model warrants further refinement and validation with a larger, more diverse dataset to improve its utility in clinical decision-making for KOA management.

Mid-term outcomes of microfragmented adipose tissue plus arthroscopic surgery for knee osteoarthritis: A randomized, active-control, multicenter clinical trial

BACKGROUND

Osteoarthritis (OA) is the most prevalent form of degenerative whole-joint disease. Before the final option of knee replacement, arthroscopic surgery was the most widely used joint-preserving surgical treatment. Emerging regenerative therapies, such as those involving platelet-rich plasma, mesenchymal stem cells, and microfragmented adipose tissue (MFAT), have been pushed to the forefront of treatment to prevent the progression of OA. Currently, MFAT has been successfully applied to treat different types of orthopedic diseases.

AIM

To assess the efficacy and safety of MFAT with arthroscopic surgery in patients with knee OA (KOA).

METHODS

A randomized, multicenter study was conducted between June 2017 and November 2022 in 10 hospitals in Zhejiang, China. Overall, 302 patients diagnosed with KOA (Kellgren-Lawrence grades 2-3) were randomized to the MFAT group (n = 151, were administered MFAT following arthroscopic surgery), or the control group (n = 151, were administered hyaluronic acid following arthroscopic surgery). The study outcomes were changes in the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, the visual analog scale (VAS) score, the Lequesne index score, the Whole-Organ Magnetic Resonance Imaging Score (WORMS), and safety over a 24-mo period from baseline.

RESULTS

The changes in the WOMAC score (including the three subscale scores), VAS pain score, and Lequesne index score at the 24-mo mark were significantly different in the MFAT and control groups, as well as when comparing values at the posttreatment visit and those at baseline (P < 0.001). The MFAT group consistently demonstrated significant decreases in the WOMAC pain scores and VAS scores at all follow-ups compared to the control group (P < 0.05). Furthermore, the WOMAC stiffness score, WOMAC function score, and Lequesne index score differed significantly between the groups at 12 and 24 mo (P < 0.05). However, no significant between-group differences were observed in the WORMS at 24 mo (P = 0.367). No serious adverse events occurred in both groups.

CONCLUSION

The MFAT injection combined with arthroscopic surgery treatment group showed better mid-term clinical outcomes compared to the control group, suggesting its efficacy as a therapeutic approach for patients with KOA.

Adipose Tissue-Derived Minimally Manipulated Products versus Platelet-Rich Plasma for the Treatment of Knee Osteoarthritis: A Systematic Review of Clinical Evidence and Meta-Analysis

The use of minimally manipulated adipose tissue (MM-AT) products is gaining increasing interest for the treatment of knee osteoarthritis (OA). MM-AT represents an easy way to exploit adipose tissue properties, although clinical evidence is still limited, as well as their benefits with respect to more documented orthobiologics like platelet-rich plasma (PRP). A systematic review and meta-analysis were performed to evaluate the safety and efficacy of MM-AT products for knee OA management. The risk of bias of the included studies was evaluated using the Dawns and Black checklist for all the included studies and RoB-2.0 for randomized controlled trials (RCTs). Thirty-three clinical studies were included in the qualitative analysis: 13 prospective case series, 10 retrospective case series, 7 RCTs, 2 retrospective comparative studies, and 1 prospective comparative study. An overall clinical improvement and few minor adverse events were observed. Five RCTs comparing MM-AT and PRP injections were meta-analyzed, showing comparable results. The analysis also highlighted the limits of the literature, with only a few high-level trials and an overall low quality. Even though the current literature is still limited, the available evidence suggests the safety and overall positive results of the intra-articular injections of MM-AT products for knee OA treatment.

Autologous micro-fragmented adipose tissue injection provides significant and prolonged clinical improvement in patients with knee osteoarthritis: a case-series study

PURPOSE

Among the conservative strategies to manage patients with symptomatic knee osteoarthritis (OA), an innovative approach exploiting the regenerative capability of adipose tissue and its resident MSCs (Mesenchymal Stem Cells or Medicinal Signalling Cells) has been proposed with encouraging results. This study aims to demonstrate the benefits of autologous micro-fragmented adipose tissue (MAT) injection in the conservative treatment of knee osteoarthritis and whether any variables may affect the outcome. This is a case series single-centre study in which patients underwent intraarticular MAT injection without any associated procedures.

METHODS

Based on inclusion and exclusion criteria, 49 patients (67 Knees) were included and retrospectively analysed with a mean follow-up of 34.04 ± 13.62 months (minimum 11 - maximum 59). Patients were assessed through the WOMAC and KOOS questionnaires at baseline (pre-treatment) and 1-, 3-, 6-, 12-, 24- and 36-month follow-up. A minimal clinically important difference (MCID) of at least 7.5 points for the WOMAC pain scale and 7.2 for the WOMAC function scale compared to the baseline value was used.

RESULTS

WOMAC and KOOS scores improved after treatment compared to baseline at all follow-ups with p < 0.001. Male gender and Kellgren-Lawrence (KL) grade 2 were associated with smaller improvement in WOMAC and KOOS scores (with respect to females and to KL grade 1, respectively) up to 24 months. The percentage of patients who reach the MCID for WOMAC pain is generally lower than that of patients who reach the MCID for WOMAC function (around 80% at all time points), but it increases significantly over time. Moreover, the baseline score of the WOMAC pain and function influence the outcome. Patients with worse symptoms are more likely to reach the MCID.

CONCLUSIONS

Intra-articular knee injection of MAT for the treatment of knee osteoarthritis (KOA), recalcitrant to traditional conservative treatments, proved to be effective in a high percentage of cases. The positive association between a worse pre-operative score and a better clinical response to the treatment would support the idea that intra-articular administration of MAT could be considered in patients with very symptomatic KOA in which joint-replacement surgeries are not indicated (or accepted).

LEVEL OF EVIDENCE

IV, case series.

Adipose Tissue-Derived Products May Present Inflammatory Properties That Affect Chondrocytes and Synoviocytes from Patients with Knee Osteoarthritis

Adipose tissue-derived cell-based injectable therapies have been demonstrated to have disease-modifying effects on joint tissues in preclinical studies on animal osteoarthritis (OA) models, but clinical results are heterogeneous and not always satisfactory. The aim of this study was to investigate the influence of adipose tissue properties on the therapeutic effects of the adipose-derived product in an in vitro OA setting. Micro-fragmented adipose tissue (MF-AT) samples were obtained from 21 OA patients (mean age 51.7 ± 11.8 years, mean BMI 25.7 ± 4.1 kg/m2). The analysis of the MF-AT supernatant was performed to analyze the release of inflammatory factors. The effects of MF-AT inflammatory factors were investigated on chondrocytes and synoviocytes gene expression levels. Patients' characteristics were analyzed to explore their influence on MF-AT inflammatory molecules and on the MF-AT effects on the gene expression of chondrocytes and synoviocytes. The study results demonstrated that adipose tissue-derived products may present inflammatory properties that influence the therapeutic potential for OA treatment, with products with a higher pro-inflammatory profile stimulating a higher expression of genes related to a more inflamed and catabolic phenotype. A higher pro-inflammatory cytokine pattern and a higher pro-inflammatory effect were found in adipose tissue-derived products obtained from OA patients with higher BMI.

Autologous microfragmented adipose tissue and leukocyte-poor platelet-rich plasma combined with hyaluronic acid show comparable clinical outcomes for symptomatic early knee osteoarthritis over a two-year follow-up period: a prospective randomized clinical trial

PURPOSE

The purpose of this prospective randomized clinical trial is to compare the clinical outcomes of three injections of leucocyte-poor platelet-rich plasma (LP-PRP) and hyaluronic acid (HA) to a single dose of autologous microfragmented adipose tissue (AMAT) in patients with mild osteoarthritis at a two-year follow-up.

METHODS

Eighty symptomatic knees in fifty patients (mean age: 62.38 ± 11.88 years) with Kellgren-Lawrence grade 0 to 2 osteoarthritis were non blinded, randomly allocated into two equal groups. Group 1 consisted of 40 knees that received autologous LP-PRP + HA; Group 2 consisted of 40 knees treated with a single dose of AMAT injection. The outcomes were measured by Tegner, Marx, Visual Analogue Scale (VAS) for pain, International Knee Documentation Committee, and Knee Injury and Osteoarthritis Outcome Score (KOOS) at 6 (T1), 12 (T2), and 24 (T3) months. Adverse events were recorded at each follow-up timepoint. To assess score differences among subjects of the same gender and age, a subgroup analysis was performed.

RESULTS

Both groups had significant clinical and functional improvement at 6, 12, and 24 months (p < 0.05). Comparing the two groups, the AMAT groups showed significantly higher pre-operative Marx score (3.35 ± 4.91 vs. 1.78 ± 3.91) and VAS score (5.03 ± 2.02 vs. 3.85 ± 1.68) (p < 0.05), higher VAS (3.89 ± 2.51 vs. 2.64 ± 2.00) at T2 and KOOS-ADL (79.60 ± 20.20 vs. 65.68 ± 23.62), and lower KOOS-Sports (50.30 ± 30.15 vs. 68.35 ± 30.39) at T3 (p < 0.05). No patient from either group had experienced major adverse effects. In the LP-PRP group 12 (30%) patients presented swelling, redness, and mild pain for one day after injection and two patients had synovitis for two days and required paracetamol and local ice. In AMAT group 5 (12.5%) patients had ecchymosis and bruising at the fat aspiration site for three days.

CONCLUSION

AMAT did not show significant superior clinical improvement compared with three LP-PRP combined with HA injections in terms of functional improvement at different follow-up points. Both procedures were safe with no major complications reporting good results at mid-term follow-up, improving knee function, pain, and quality of live regardless of age and gender.

LEVEL OF EVIDENCE

Level I-Prospective Randomized Clinical Trial.

Comparative Efficacy of Intra-Articular Injection, Physical Therapy, and Combined Treatments on Pain, Function, and Sarcopenia Indices in Knee Osteoarthritis: A Network Meta-Analysis of Randomized Controlled Trials

Knee osteoarthritis (KOA) is associated with a high risk of sarcopenia. Both intra-articular injections (IAIs) and physical therapy (PT) exert benefits in KOA. This network meta-analysis (NMA) study aimed to identify comparative efficacy among the combined treatments (IAI+PT) in patients with KOA. Seven electronic databases were systematically searched from inception until January 2023 for randomized controlled trials (RCTs) reporting the effects of IAI+PT vs. IAI or PT alone in patients with KOA. All RCTs which had treatment arms of IAI agents (autologous conditioned serum, botulinum neurotoxin type A, corticosteroids, dextrose prolotherapy (DxTP), hyaluronic acid, mesenchymal stem cells (MSC), ozone, platelet-rich plasma, plasma rich in growth factor, and stromal vascular fraction of adipose tissue) in combination with PT (exercise therapy, physical agent modalities (electrotherapy, shockwave therapy, thermal therapy), and physical activity training) were included in this NMA. A control arm receiving placebo IAI or usual care, without any other IAI or PT, was used as the reference group. The selected RCTs were analyzed through a frequentist method of NMA. The main outcomes included pain, global function (GF), and walking capability (WC). Meta-regression analyses were performed to explore potential moderators of the treatment efficacy. We included 80 RCTs (6934 patients) for analyses. Among the ten identified IAI+PT regimens, DxTP plus PT was the most optimal treatment for pain reduction (standard mean difference (SMD) = -2.54) and global function restoration (SMD = 2.28), whereas MSC plus PT was the most effective for enhancing WC recovery (SMD = 2.54). More severe KOA was associated with greater changes in pain (β = -2.52) and WC (β = 2.16) scores. Combined IAI+PT treatments afford more benefits than do their corresponding monotherapies in patients with KOA; however, treatment efficacy is moderated by disease severity.

An observational study evaluating the efficacy of microfragmented adipose tissue in the treatment of osteoarthritis

Aim: Osteoarthritis (OA) prevalence is increased in ageing and obese populations. This prospective single-arm cohort study aimed to investigate the efficacy of autologous microfragmented adipose tissue treatment of severe knee or shoulder OA. Materials & methods: Participants received an intra-articular microfragmented adipose tissue injection to the affected joint(s). Multiple patient reported outcome measures (PROMS) were recorded from 0 to 52 weeks for 63 consecutive joints. Results: Compared with baseline, there were significant improvements in all PROMS from 2 to 12 weeks and maintained at 52 weeks. Regression analysis revealed an inverse correlation with BMI and change in PROMS for knee joints. Conclusion: Our observed findings suggest this approach represents a safe, effective treatment for moderate-to-severe knee and shoulder OA, although efficacy may be reduced with increasing obesity.

Autologous micro-fragmented adipose tissue associated with arthroscopy in moderate–severe knee osteoarthritis: outcome at two year follow-up

Background

Adipose tissue has recently gained growing interest in the treatment of osteoarthritis (OA). The aim of the present study was to evaluate the efficacy of a single injection of autologous micro-fragmented adipose tissue (aMFAT) associated with arthroscopy (cartilage debridement/meniscal regularization or selective meniscectomy/micro-drilling) for symptomatic knee OA.

Methods

This retrospective, single-center study included 49 patients (50 knees) affected by knee OA (radiographic Kellgren-Lawrence III-IV) treated with a single injection of autologous micro-fragmented adipose tissue and knee arthroscopy. Knee Injury and Osteoarthritis Outcome Score (KOOS) and subjective International Knee Documentation Committee (IKDC) score were the primary outcome measures and were collected at one and 2 years post-operatively. Patients were divided into clusters based on age, complexity of arthroscopic procedures and chondral lesion grade.

Results

Four patients underwent knee replacement (8%). No major adverse events were reported. Minimal Clinically Important Difference (MCID) for KOOS and IKDC was reached by 84 and 74% of all cases at 1 year and by 80 and 76% at 2 years, respectively. High grade chondral lesions negatively affected the outcome at 2 years follow-up (p < 0.05 for IKDC, KOOS overall and 3 out of 5 subscales).

Conclusion

The injection of micro-fragmented adipose tissue associated with arthroscopy demonstrated to be a safe and effective procedure for the treatment of knee OA, with a substantial improvement in IKDC and KOOS scores and without major complications.

Is intra-articular injection of autologous micro-fragmented adipose tissue effective in hip osteoarthritis? A three year follow-up

Background

Recently, increased attention on regenerative medicine and biological injective treatments have been proposed to restore native cartilage. Micro-fragmented adipose tissue (MFAT) has been studied for its anti-inflammatory, paracrine, and immunomodulatory effects. The long-term effects of MFAT are still poorly understood: the aim of the present study is to demonstrate how hip articular injections with autologous MFAT can have an impact on clinical outcomes.

Methods

Seventy-one consecutive patients affected by early hip osteoarthritis underwent an ultrasound-guided hip injection of autologous MFAT between June 2017 and December 2018. Patients were divided into four groups according to the Oxford Hip Score. All patients received 4 mL of autologous micro-fragmented adipose tissue under an ultrasound guide. A clinical evaluation was done between 29 and 41 months after the initial treatment. During this follow-up period, we recorded any new treatment the patients had done, whether that be injection or arthroplasty surgery.

Results

The study included 55 patients. Out of 55 patients, 28 saw benefits and were in no need of further treatment. Moreover, the score between the beginning and control increased by 6.9 points. Ten patients underwent a new articular injection: the mean time between the two injections was 635.7 ± 180 days. Seventeen patients underwent total hip replacement: the mean period between the autologous MFAT injection and the surgery was 495 days.

Conclusion

This study found that intra-articular injections with autologous MFAT achieve beneficial clinical results in patients affected by early to moderate hip osteoarthritis, with an OHS between 48 and 30. Furthermore, these subjects are the ideal patients for whom this treatment obtains good clinical results.

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.

Platelet-Rich Plasma Versus Microfragmented Adipose Tissue for Knee Osteoarthritis: A Randomized Controlled Trial

Background:

Platelet-rich plasma (PRP) has been established as safe and effective for knee osteoarthritis (OA). Another orthobiologic therapy, microfragmented adipose tissue (MFAT), has gained attention because of its heterogeneous cell population (including mesenchymal stem cells). However, prospective comparative data on MFAT are lacking. Because of the safety, efficacy, and simplicity of PRP, new therapeutics such as MFAT should be compared directly with PRP.

Purpose:

To compare patient-reported outcomes of a single injection of PRP versus MFAT for knee OA.

Study Design:

Randomized controlled trial; Level of evidence, 2.

Methods:

A total of 58 patients with symptomatic knee OA (Kellgren-Lawrence grades 1-4) were randomized to receive a single injection of either leukocyte-rich PRP or MFAT under ultrasound guidance. PRP was created by processing 156 mL of whole blood. MFAT was created by harvesting 30 mL of adipose tissue via standard lipoaspiration. Scores for the Knee injury and Osteoarthritis Outcome Score (KOOS) subscales and visual analog scale for pain with Activities of Daily Living (VAS-ADL) were recorded at baseline and at 1, 3, and 6 months after the injection. The primary outcome was the KOOS–Pain subscore at 6 months after the injection.

Results:

The PRP group (n = 30) had a mean volume of 5.12 ± 1.12 mL injected. This consisted of a mean platelet count of 2673.72 ± 1139.04 × 10³/µL and mean leukocyte count of 25.36 ± 13.27 × 10³/µL (67.81% lymphocytes, 18.66% monocytes, and 12.33% neutrophils). The MFAT group (n = 28) had a mean volume of 7.92 ± 3.87 mL injected. The mean total nucleated cell count was 3.56 ± 4.62 million/mL. In both groups, KOOS subscale and VAS-ADL scores improved from baseline, and there was no significant difference between the PRP and MFAT groups in the final KOOS–Pain subscore (80.38 ± 16.07 vs 81.61 ± 16.37, respectively; P = .67) or any other outcome score.

Conclusion:

A single injection of either PRP or MFAT resulted in a clinically meaningful improvement for patients with knee OA at 6 months, with no difference between treatment groups.

Registration:

NCT04351087 (ClinicalTrials.gov identifier).

Non-homologous use of adipose-derived cell and tissue therapies: Osteoarthritis as a case study

Adipose tissue is widely recognized as an abundant and accessible human tissue that serves as a source of cells and extracellular matrix scaffolds for regenerative surgical applications. Increasingly, orthopedic surgeons are turning to adipose tissue as a resource in their treatment of osteoarthritis and related conditions. In the U.S., the regulatory landscape governing the orthopedic surgical utilization of autologous and allogeneic adipose tissue remains complex. This manuscript reviews the Food and Drug Administration's nomenclature and guidance regarding adipose tissue products. Additionally, it surveys recent pre-clinical and clinical trial literature relating to the application of adipose-derived cells and tissues in the treatment of osteoarthritis.

Mesenchymal Stem Cell Mechanisms of Action and Clinical Effects in Osteoarthritis: A Narrative Review

With the insufficient satisfaction rates and high cost of operative treatment for osteoarthritis (OA), alternatives have been sought. Furthermore, the inability of current medications to arrest disease progression has led to rapidly growing clinical research relating to mesenchymal stem cells (MSCs). The availability and function of MSCs vary according to tissue source. The three primary sources include the placenta, bone marrow, and adipose tissue, all of which offer excellent safety profiles. The primary mechanisms of action are trophic and immunomodulatory effects, which prevent the further degradation of joints. However, the function and degree to which benefits are observed vary significantly based on the exosomes secreted by MSCs. Paracrine and autocrine mechanisms prevent cell apoptosis and tissue fibrosis, initiate angiogenesis, and stimulate mitosis via growth factors. MSCs have even been shown to exhibit antimicrobial effects. Clinical results incorporating clinical scores and objective radiological imaging have been promising, but a lack of standardization in isolating MSCs prevents their incorporation in current guidelines.

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.

Attenuation of osteoarthritis progression through intra-articular injection of a combination of synovial membrane-derived MSCs (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome)

PURPOSE

Osteoarthritis (OA) as a progressive destructive disease of articular cartilage is the most common joint disease characterized by reduction of joint cartilage thickness, demolition of cartilage surface and new bone formation. To overcome these problems, the purpose of the current research was to evaluate and compare the in vivo effects of synovial membrane-derived mesenchymal stem cell (SMMSCs), platelet-rich plasma (PRP) and conditioned medium (secretome) on collagenase II-induced rat knee osteoarthritis (KOA) remedy.

METHODS

For the first step, SMMSCs were isolated and characterized. Also, secretome was collected from SMMSCs culture. Furthermore, PRP was collect from the rat heart venous blood. Second, two injection of collagenase II with an interval of 3 days was performed in the knee intra-articular space to induce osteoarthritis. Two weeks later, animals were randomly divided into 6 groups. Control group without treatment, positive group: taken an intra-articular sodium hyaluronate injection (0.1 ml), treatment groups taken an intra-articular injection of; treatment 1: SMMSCs (5 × 10⁶), treatment 2: SMMSCs (5 × 10⁶)/secretome (50 µl), treatment 3: SMMSCs (5 × 10⁶)/PRP (50 µl), and treatment 4: SMMSCs (5 × 10⁶)/ secretome (50 µl)/ PRP (50 µl). Three months later, rats were killed and the following assessments were executed: radiography, histopathology, and immunohistochemistry.

RESULTS

Our findings represented that a combination of the SMMSCs/secretome/PRP had a considerable effect on glycosaminoglycans (GAGs) and collagen II contents, articular cartilage preservation, compared with other groups. In addition, combination of the SMMSCs with PRP and secretome showed the lowest expression of mmp3, while SOX9 had the highest expression in comparison with other groups. Also, SMMSCs-injected groups demonstrated better results compared with positive and control groups.

CONCLUSIONS

Injecting a combination of the SMMSCs/secretome/PRP resulted in better efficacy in terms of joint space width, articular cartilage surface continuity and integrity, sub-chondral bone and ECM constituents such as collagen II. Indeed, transplantation of this combination could be considered as a preliminary therapy for clinical trial study in the future.

Potential New Treatments for Knee OA: A Prospective Review of Registered Trials

We aimed to evaluate potential new treatments for knee osteoarthritis (OA). The National Institute of Health ClinicalTrials.gov database was searched for “Osteoarthritis, Knee”. We found 565 ongoing interventional studies with a total planned enrollment of 111,276 subjects. Ongoing studies for knee OA represent a very small fraction of the registered clinical trials, but they are over a quarter of all knee trials and over two thirds of all OA studies. The most researched topic was arthroplasty, with aspects such as implant design changes, cementless fixation, robotic guidance, pain management, and fast track recovery. Intraarticular injections focused on cell therapies with mesenchymal stem cells sourced from adipose tissue, bone marrow, or umbilical cord. We could see the introduction of the first disease modifying drugs with an impact on knee OA, as well as new procedures such as geniculate artery embolization and geniculate nerve ablation.

Platelets and Adipose Stroma Combined for the Treatment of the Arthritic Knee

Knee osteoarthritis (OA) leads to significant pain and disability, prompting new cell-based injections to lessen the symptoms. Biological therapies such as autologous microfragmented adipose tissue (AMAT) and a stromal vascular fraction (SVF) are a common source for harvesting mesenchymal and progenitor cells. Platelet-rich plasma (PRP) is associated with cytokines and growth factors. Recent studies have reported good clinical outcomes with AMAT, SVF, and PRP in knee osteoarthritis treatment. However, the preparation, processing, and application technique are vital to achieving satisfactory results. Many studies have examined outcomes after AMAT, SVF, or PRP injection, with encouraging results. Still, there is a lack of studies describing a technique that combines both methods, the timing, and the amount of SVF or PRP injected. This technical note's objective was to describe a standardized new technique composed of platelet and adipose stroma to treat knee osteoarthritis (OA) and the processing method.

Microfragmented Adipose Tissue Injection (MFAT) May Be a Solution to the Rationing of Total Knee Replacement: A Prospective, Gender-Bias Mitigated, Reproducible Analysis at Two Years

Background

Knee osteoarthritis (KOA) is a significant cause of disability in a globally ageing population. Knee replacement surgery has been shown to improve function and quality of life. Access to this intervention can be limited for a number of reasons including rationing of care, lack of healthcare provision in austere environments, and more recently, due to the cessation of elective orthopaedic care as a result of the COVID pandemic. Referral for knee replacement surgery is often guided by the patient's Oxford Knee Score (OKS). Recent therapies including treatment with microfragmented adipose tissue (MFAT) have emerged as alternatives to relieve pain and improve function in such patients.

Method

We identified all patients with KOA Kellgren-Lawrence grade 3 and 4 in our dataset of patients treated with a single injection of MFAT and applied published OKS thresholds for referral for TKR to separate them into 3 cohorts according to their functional impairment. 220 patients (95 females, 125 males) with KOA were given one MFAT injection. The function (OKS) and quality of life (EuroQol-5) prior to and 24 months after therapy were compared.

Results

MFAT injection provided a statistically significant improvement in the quality of life (EQ-5D) at 24 months in patients with a baseline OKS of 39 or less (p value: <0.001) as well as those with OKS of 27 or less who are deemed suitable for a knee replacement (p value: <0.001).

Conclusion

MFAT injection improves quality of life in patients with KOA who are deemed suitable for the knee replacement. MFAT is a low-morbidity alternative biological treatment and can delay the need for total knee replacement in suitable patients.

A Prospective Study Comparing Leukocyte-Poor Platelet-Rich Plasma Combined with Hyaluronic Acid and Autologous Microfragmented Adipose Tissue in Patients with Early Knee Osteoarthritis

The objective of this study was to compare the clinical efficacy of repeated doses of leucocyte-poor platelet-rich plasma (LP-PRP) plus hyaluronic acid (HA) to a single dose of autologous microfragmented adipose tissue (AMAT) injections in patients with early osteoarthritis (OA) symptoms. Eighty knees in 50 patients (mean age: 61.3 years) were randomly allocated into two equal groups in a nonblinded design and prospectively followed for 12 months. Group 1 received three intra-articular injections (1 month apart) using autologous LP-PRP+HA. Group 2 received a single dose of AMAT injection. Outcomes were measured by PROMs Tegner, Marx, visual analog scale, and Knee Injury and Osteoarthritis Outcome Score (KOOS) at 6 and 12 months. Both groups had significant clinical and functional improvement at 6 and 12 months. The differences between groups were statistically significant in Tegner score and KOOS symptoms (both P < 0.05) at 6 months in group 2. The test with statistically significant differences (P < 0.05) at 12 months was Tegner (P < 0.001), with group 2 having a higher median than group 1. LP-PRP+HA and AMAT lead to clinical and functional improvement at 6 and 12 months. AMAT showed better clinical results in Tegner and KOOS symptoms at 6 months and Tegner at 12 months. Understanding which therapy offers the most benefits with the least risk can significantly improve the quality of life for millions of people affected by OA. Long-term randomized controlled studies are needed to verify differences in efficacy.