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

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.

Evaluation of Spin in Clinical Trials of Mesenchymal Stromal Cells for the Treatment of Knee Osteoarthritis: A Systematic Review

BACKGROUND

The regenerative potential of mesenchymal stromal cells (MSCs) has sparked interest in their use for knee osteoarthritis. Concurrently, there have been investigations on how data in scientific journals are reported and how they may influence readers' interpretations, or "spin bias." These studies are at risk for bias, given the limited number of patients and inconsistent blinding or controls. The risk of spin bias also complicates the interpretation, as results may be presented in a way that favors a particular outcome.

PURPOSE

To quantify and characterize spin bias in clinical trials of MSCs for knee osteoarthritis.

STUDY DESIGN

Systematic review.

METHODS

PubMed and Embase searches were conducted using the terms "mesenchymal stem cells" or "MSCs" and "knee arthritis" or "osteoarthritis" and "therapy" or "treatment" or "regeneration." Overall, 2 independent reviewers classified spin as high, moderate, or low and as 1 of 3 types: (1) emphasizing statistically significant results, (2) interpreting nonsignificant results as treatment effectiveness, and (3) claiming treatment benefits despite nonsignificant results. Journals were categorized as orthopaedic or nonorthopaedic. Descriptive statistics, the chi-square test, and the Fisher exact test were used to analyze the data, with alpha set at P < .05.

RESULTS

Among the 54 studies, spin was found in 80.0% of articles, with 14.5% having high, 25.5% moderate, and 40.0% low levels of spin. Type 1 was found in 54.5% of articles, type 2 in 18.2%, and type 3 in 29.1%. Spin was less frequently observed in the Methods section of articles compared with the abstract (17.52; P = .003). Reports on adipose-derived MSCs were associated with a higher frequency and level of spin compared with reports on MSCs from other sources (18.92; P = .026). There was no difference in the frequency of spin between orthopaedic and nonorthopaedic journals (0.48; P = .49) and no association with the impact factor (5.34; P = .07). There was no association between spin and financial disclosures (0.02; P = .577).

CONCLUSION

Spin bias was present in most MSC-related trials for knee osteoarthritis, with a higher frequency among those that utilized adipose-derived MSCs. Understanding the prevalence and strategies of spin can mitigate any potential misinterpretations of study outcomes.

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

BACKGROUND

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

PURPOSE

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

STUDY DESIGN

Systematic review. Level 1a.

METHODS

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

RESULTS

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

CONCLUSION

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

Microfragmented Adipose Tissue Has No Advantage Over Platelet-Rich Plasma and Bone Marrow Aspirate Injections for Symptomatic Knee Osteoarthritis: A Systematic Review and Meta-analysis

BACKGROUND

Microfragmented adipose tissue has been proposed for intra-articular treatment of knee osteoarthritis. There are little data comparing the outcomes of treatment between microfragmented adipose tissue and other biological treatments.

PURPOSE

To perform a systematic review and meta-analysis comparing microfragmented aspirated fat injections to other orthobiologics, hyaluronic acid, and corticosteroid injections for symptomatic knee osteoarthritis.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 2.

METHODS

A systematic review of the literature was performed to identify pertinent publications in the MEDLINE, Embase, Scopus, and Google Scholar databases, including all level 1 to 3 studies from 2000 to 2023. Validated knee scores (visual analog scale [VAS] for pain, Knee injury and Osteoarthritis Outcome Score [KOOS], Lysholm, International Knee Documentation Committee) were included as outcome measures. Risk of bias was assessed using Cochrane tools. The Grading of Recommendations Assessment, Development and Evaluation system was used to assess the quality of the body of evidence and the modified Coleman Methodology Score was used to assess study quality. Heterogeneity was assessed using χ2 and I2 statistics.

RESULTS

Five studies were included in the analysis. One study had a high risk of bias; 4 studies had some risk of bias. The overall study quality was fair, and the certainty of evidence was low. The pooled estimate for VAS scores did not demonstrate significant differences at 3, 6, and 12 months. The pooled estimate for the KOOS Pain, Symptoms, Activities of Daily Living, Sport and Recreation, and Quality of Life subscales did not demonstrate significant differences at 3, 6, and 12 months.

CONCLUSION

The results of this systematic review and meta-analysis demonstrated that there were no statistically significant differences for both the clinical outcomes and pain scores between microfragmented adipose tissue and other orthobiologics for the treatment of knee osteoarthritis. However, modest study quality, some risk of bias, and low certainty of evidence reduce external validity, and these results must be viewed with some caution.

Narrative review and call to action on reporting and representation in orthobiologics research for knee osteoarthritis

Osteoarthritis affects a significant portion of U.S. adults, and knee osteoarthritis contributes to 80% of disease burden. Previous data have shown that non-White patient populations often report worse symptoms and less favorable outcomes following arthroplasty, a definitive treatment for knee osteoarthritis. There is a lack of demographics data on race/ethnicity, as well as socioeconomic status (SES) and social determinants of health (SDOH), in knee osteoarthritis treatment guidelines and knee arthroplasty research. In addition, there is underrepresentation of non-White patient populations in the existing treatment guidelines for knee osteoarthritis. Over the past decade, orthobiologics have emerged as an alternative to surgical intervention. Our hypothesis is that there would be a similar lack of reporting of demographics data and underrepresentation of non-White populations in studies pertaining to orthobiologics, including evaluating differences in outcomes. This study reviewed U.S.-based research in orthobiologics as a treatment option for knee osteoarthritis. We identified a lack of demographics reporting in terms of race/ethnicity, and none of the studies reported SES or SDOH. Non-White populations were underrepresented; White patients contributed to 80% or more of all study populations that reported race/ethnicity. None studied the correlation between symptoms and outcome measures, and the race/ethnicity, SES, and SDOH of the patients. Based on a review of existing literature, we strongly advocate for ongoing research encompassing patients of all races/ethnicities, SES, and SDOH, and an exploration into potential variations in symptoms and outcomes among distinct population subgroups. Furthermore, SES barriers may influence health care delivery on orthobiologics for disadvantaged populations.

Randomized Controlled Trials for Platelet-Rich Plasma Use in Knee Osteoarthritis Rarely Report Key Sociodemographic Patient Variables: A Scoping Review

Purpose

To investigate the characteristics and rate of sociodemographic variables reported in randomized controlled trials (RCTs) studying platelet-rich plasma (PRP) injections in the treatment of knee osteoarthritis (OA).

Methods

In January 2024, PubMed, Scopus, and Web of Science databases were queried for the phrase "Platelet-Rich Plasma Knee Osteoarthritis." Included studies were RCTs investigating PRP use in knee OA published in English between 2012 and 2023. Each RCT was inspected for patient age and sex or gender as well as the following sociodemographic variables: race, ethnicity, insurance status, income, housing status, work status, and education. Data were presented in a descriptive fashion and analyzed using χ2 test and Fisher's exact test to compare 2 and 3 categorical variables, respectively, with significance defined as P < .05.

Results

From 2012 through 2023, 71 RCTs met inclusion criteria. Included publications reported both age and sex or gender in 71/71 papers (100%). Reporting rates for other sociodemographic variables were as follows: race (3/71, 4.23%), work status (5/71, 7.04%), and education (3/71, 4.23%). No studies included the ethnicity, insurance status, income, or housing status of the enrolled patients. There was no difference in reporting sociodemographic variables by journal (P = .083) or by year of publication (P = .340). Sociodemographic variables were reported significantly less frequently than age and sex or gender (P < .001).

Conclusions

In this study, we found that age and sex or gender are always reported in RCTs of PRP use for knee OA. However, other sociodemographic variables, such as race, work status, and education, that may be important to understand are rarely reported.

Clinical Relevance

Sociodemographic variables may affect outcomes in knee osteoarthritis. It is important to understand which of these variables are most studied and which variables are most overlooked. This will help us better understand the quality of the available information.

Adipose-derived stem cells and knee osteoarthritis: New perspectives, old concerns

In this editorial, we comment on the paper by Muthu et al published in the recent issue of the journal. This editorial review focusses on the use of adipose-derived stem cells (ADSCs) in knee osteoarthritis treatment. We discuss the differences between the stromal vascular fraction and microfragmented adipose tissue and highlight the results of clinical studies comparing both treatments and the use of hyaluronic acid, platelet-rich plasma, and bone marrow aspirate concentrate. The use of expanded ADSCs is also discussed; moreover, concerns regarding treatment with ADSCs, particularly the heterogeneity of published studies and the need to standardize protocols to explore clinical potential is explored.

Relationship of Body Mass Index on Patient-Reported Outcomes After Platelet-Rich Plasma Versus Microfragmented Adipose Tissue for Knee Osteoarthritis: A Secondary Analysis of a Randomized Controlled Trial

OBJECTIVE

Body mass index is known to contribute to outcomes for patients with knee osteoarthritis. Furthermore, body mass index influences the protein expression of orthobiologic treatments like platelet-rich plasma and microfragmented adipose tissue. We performed a secondary analysis of the association of body mass index with patient-reported outcomes for patients with knee osteoarthritis who received either platelet-rich plasma or microfragmented adipose tissue injections.

METHODS

Seventy-one patients with knee osteoarthritis were randomized to receive a single ultrasound-guided injection of platelet-rich plasma or microfragmented adipose tissue. Platelet-rich plasma was created from 180 cc of anticoagulated blood and processed using a double-spin, buffy-coat concentration system. Microfragmented adipose tissue was created using autologous lipoaspirate that was processed according to minimal manipulation guidelines. Patient-reported outcomes and osteoarthritis outcome scores (Knee Osteoarthritis and injury Outcome Score) were tracked for 12 mos.

RESULTS

Forty-nine patients (platelet-rich plasma = 23, microfragmented adipose tissue = 26) completed 12-mo follow-up. Knee Osteoarthritis and injury Outcome Score quality of life and activity of daily living subscores were inversely correlated (both P < 0.05) with body mass index in the microfragmented adipose tissue but not platelet-rich plasmagroup. Knee Osteoarthritis and injury Outcome Score pain and sport subscores showed a trend toward inverse correlation with body mass index in the microfragmented adipose tissue group ( P = 0.07 and P = 0.06, respectively), but not platelet-rich plasma.

CONCLUSIONS

Body mass index was negatively associated with patient-reported outcomes in patients who received microfragmented adipose tissue injections for knee osteoarthritis, but not for patients receiving platelet-rich plasma.

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

BACKGROUND

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

QUESTIONS/PURPOSES

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

METHODS

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

RESULTS

The use of uninformative control groups (treatments less invasive than the tested treatment, or treatments that might not outperform placebo but are not acknowledged as such) was found in 46% (47 of 103) of included studies. After accounting for potential confounding, there was no association between reporting positive treatment effects and the use of an uninformative control group. Studies with a low risk of bias had a lower likelihood of reporting a positive treatment effect (OR 0.2 [95% confidence interval 0.05 to 0.9]; p = 0.04, model pseudo R2 = 0.21).

CONCLUSION

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

LEVEL OF EVIDENCE

Level I, therapeutic study.

Platelet-Rich Plasma Versus Alternative Injections for Osteoarthritis of the Knee: A Systematic Review and Statistical Fragility Index-Based Meta-analysis of Randomized Controlled Trials

BACKGROUND

Based in part on the results of randomized controlled trials (RCTs) that suggest a beneficial effect over alternative treatment options, the use of platelet-rich plasma (PRP) for the management of knee osteoarthritis (OA) is widespread and increasing. However, the extent to which these studies are vulnerable to slight variations in the outcomes of patients remains unknown.

PURPOSE

To evaluate the statistical fragility of conclusions from RCTs that reported outcomes of patients with knee OA who were treated with PRP versus alternative nonoperative management strategies.

STUDY DESIGN

Systematic review and meta-analysis; Level of evidence, 2.

METHODS

All RCTs comparing PRP with alternative nonoperative treatment options for knee OA were identified. The fragility index (FI) and reverse FI were applied to assess the robustness of conclusions regarding the efficacy of PRP for knee OA. Meta-analyses were performed to determine the minimum number of patients from ≥1 trials included in the meta-analysis for which a modification on the event status would change the statistical significance of the pooled treatment effect.

RESULTS

In total, this analysis included outcomes from 1993 patients with a mean ± SD age of 58.0 ± 3.8 years. The mean number of events required to reverse significance of individual RCTs (FI) was 4.57 ± 5.85. Based on random-effects meta-analyses, PRP demonstrated a significantly higher rate of successful outcomes when compared with hyaluronic acid (P = .002; odds ratio [OR], 2.19; 95% CI, 1.33-3.62), as well as higher rates of patient-reported symptom relief (P = .019; OR, 1.55; 95% CI, 1.07-2.24), not requiring a reintervention after the initial injection treatment (P = .002; OR, 2.17; 95% CI, 1.33-3.53), and achieving the minimal clinically important difference (MCID) for pain improvement (P = .007; OR, 6.19; 95% CI, 1.63-23.42) when compared with all alternative nonoperative treatments. Overall, the mean number of events per meta-analysis required to change the statistical significance of the pooled treatment effect was 8.67 ± 4.50.

CONCLUSION

Conclusions drawn from individual RCTs evaluating PRP for knee OA demonstrated slight robustness. On meta-analysis, PRP demonstrated a significant advantage over hyaluronic acid as well as improved symptom relief, lower rates of reintervention, and more frequent achievement of the MCID for pain improvement when compared with alternative nonoperative treatment options. Statistically significant pooled treatment effects evaluating PRP for knee OA are more robust than approximately half of all comparable meta-analyses in medicine and health care. Future RCTs and meta-analyses should consider reporting FIs and fragility quotients to facilitate interpretation of results in their proper context.

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

BACKGROUND

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

Orthobiologics in knee osteoarthritis, dream or reality?

Cartilage restoration or repair, also known as orthobiologic therapy, is indicated after the failure of conservative or supportive treatment. However, there is paucity in evidence supporting the efficacy of orthobiologic therapy. The blood-derived products, such as platelet-rich plasma (PRP), is one of the commonly used orthobiologic therapy for knee osteoarthritis. Several studies have shown that PRP is superior to other treatments, but the anatomic changes are scarce. Treatment with mesenchymal stem cells (MSCs) offers the greatest potential for curing degenerative disease due to their self-renewal ability, ability to migrate towards injured tissues (homing/trafficking), and ability to promote repair and regeneration of osteochondral defects. However, ethical concerns and high costs remain major challenges associated with MSC therapy. Gene therapy, another promising orthobiologic therapy, is currently in phase II clinical trial and has shown promising results. The key factors for successful orthobiologic therapy include patient selection, appropriate dosing, treatment of underlying mechanical problems, age, severity, and cost-effectiveness.

Microfragmented adipose tissue versus platelet-rich plasma in the treatment of knee osteoarthritis: a systematic review and meta-analysis

This meta-analysis focuses on the controversial efficacy and safety of microfragmented adipose tissue (MFAT) as compared with platelet-rich plasma (PRP) in the clinical treatment of knee osteoarthritis (KOA). We have attempted to provide an evidence-based medicine protocol for the conservative treatment of KOA. Researchers collected and compared randomized controlled trials (RCTs) that used microfragmented adipose tissue and platelet-rich plasma to treat knee osteoarthritis. We searched CNKI, Wanfang Database, CMJD, PubMed, Sinomed, Cochrane Library, and Embase for studies published up to May 31, 2023. Two investigators independently screened literature, extracted data, and assessed bias risk using the Cochrane bias risk tool. The researchers then performed a meta-analysis using Revman 5.4 statistics software provided by the Cochrane Library. A total of 4 randomized controlled trials involving 266 patients (326 knees) were included. There were 161 knees in the MFAT group and 165 knees in the PRP group. Meta-analysis showed a statistically significant difference in VAS scores between the MFAT group and the PRP group at 12 months after treatment [MD=0.99, 95% CI (0.31, 1.67), P=0.004]. This result showed that VAS scores were lower in the PRP group than in the MFAT group, and that PRP injection reduced pain more effectively than MFAT injection. At 6 months after treatment, Tegner activity scale scores in the MFAT group were higher than that in the PRP group [MD=0.65, 95% CI (0.11, 1.19), P=0.02], and the difference was statistically significant. There were no significant differences in the remaining indicators between the two groups. Based on this meta-analysis, PRP appears to be more effective than MFAT in treating KOA in terms of long-term pain relief. However, MFAT was superior to PRP in improving short-term activity function. Overall, there was no significant difference between MFAT and PRP in the treatment of KOA. In addition, MFAT does not increase the risk of adverse events compared to PRP. However, at present, there are few clinical studies on MFAT and PRP, which need to be verified by more rigorously designed clinical trials.

Arthroscopic Management of Moderate-to-Severe Osteoarthritis of the Knee: A Systematic Review

BACKGROUND

Total knee arthroplasty (TKA) is the procedure of choice for osteoarthritis of the knee (OAK) when conservative treatment fails; however, high rates of dissatisfaction and poor implant longevity dissuade younger patients from TKA. There is a paucity of evidence that report outcomes and clinical effectiveness of arthroscopic knee procedures in patients with end-stage (grade 3-4) OAK. The purpose of this systematic review was to evaluate the efficacy of arthroscopic treatment for patients with moderate-to-severe (grade 3-4) OAK.

METHODS

A systematic review of the literature was performed with the terms "Knee," "Osteoarthritis," and/or "Arthroscopic debridement," "Arthroscopic lavage," "Arthroscopic microfracture," "Arthroscopic chondroplasty," "debridement," "lavage," "chondroplasty," "microfracture," and/or "arthroscopy" in PubMed (MEDLINE), Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL) databases in November 2023 according to Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Databases were searched for studies that evaluated outcomes (e.g., pain, function, and conversion to TKA) for patients with Kellgren-Lawrence grade 3 to 4 OAK after knee arthroscopy (including debridement, lavage, microfracture, or chondroplasty) at a minimum 6-month follow-up. Percent improvement from preoperative score was the primary outcome measure. Secondary outcome measures included achievement of minimal clinically importance difference and conversion to TKA.

RESULTS

Nine studies (410 knees with grades 3-4 OAK) were included. Arthroscopic debridement and lavage resulted in a 18.8% to 53.1% improvement at short-term follow-up (e.g., 6 months to 3 years) and a 50.0% improvement at long-term follow-up (e.g., 10 years) in knees with grade 3 OAK and a 15.0% to 41.3% improvement at short-term follow-up and a 46.9% improvement at long-term follow-up in knees with grade 4 OAK. Arthroscopic debridement and microfracture resulted in 1.6% to 50.8% improvement at short-term follow-up in knees with grade 3 OAK. No studies included long-term outcomes or evaluated knees with grade 4 OAK after arthroscopic debridement and microfracture. Conversion to TKA after arthroscopic debridement and lavage occurred in 21.9% of patients with grade 3 OAK and in 35.0% of patients with grade 4 OAK at short-term follow-up and in 47.4% of patients with grade 3 OAK and in 76.5% of patients with grade 4 OAK at long-term follow-up. Conversion to TKA after arthroscopic debridement and microfracture occurred in 10.9% of patients with grade 3 and 4 OAK at long-term follow-up.

CONCLUSION

Arthroscopic debridement, lavage, and microfracture can provide short- and long-term symptomatic relief and improvement in function by up to 50.0% in patients with grade 3 to 4 OAK. These procedures may result in fewer patients with grade 3 OAK undergoing TKA compared with patients with grade 4 OAK.

LEVEL OF EVIDENCE

Level IV; systematic review of Level II-IV studies. See Instructions for Authors for a complete description of levels of evidence.

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

Purpose

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

Methods

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

Results

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

Conclusion

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

Level of Evidence

Level I, systematic review of RCTs.

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

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

Randomized Controlled Trials on Platelet-Rich Plasma for Knee Osteoarthritis Poorly Adhere to the Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO) Guidelines: A Systematic Review

BACKGROUND

Platelet-rich plasma (PRP) treatment for knee osteoarthritis has grown exponentially over the past decade; however, its scientific evaluation is highly variable. The American Academy of Orthopaedic Surgeons addressed the need for the standardization of orthobiologics studies by publishing the Minimum Information for Studies Evaluating Biologics in Orthopaedics (MIBO) guidelines in May 2017. In total, the MIBO guidelines are divided into 12 categories, encompassing 23 checklist items.

HYPOTHESIS/PURPOSE

The purpose of this study was to analyze how well randomized controlled trials (RCTs) on PRP interventions for knee osteoarthritis adhered to the MIBO guidelines. We hypothesized that most articles would report <80% of the MIBO criteria.

STUDY DESIGN

Systematic review; Level of evidence, 1.

METHODS

PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines were used to perform a systematic review in the PubMed/MEDLINE and Web of Science databases. Inclusion criteria included English-language RCTs that assessed PRP interventions for knee osteoarthritis and reported beginning patient enrollment in June 2017 or later. The original 23 MIBO checklist items were separated and modified into a 44-point checklist. Adherence was determined by calculating the total percentage of checklist items that each article adequately and clearly reported from the 44-point checklist.

RESULTS

A total of 25 RCTs (2356 patients) were included in this study. The weighted mean age was 57.7 ± 4.4 years, with 42.9% being male. On average, only 53.1% ± 10.4% (range, 31.8%-77.3%) of the 44-point MIBO checklist items were reported per article. No articles had adherence rates ≥80%, 5 (20.0%) had rates between 60% and 79.9%, and 20 (80.0%) had rates ≤59.9%. Categories fluctuated in adherence, with "Intervention" having the greatest adherence (100.0%) and "Activation" having the lowest (14.0%). Additionally, 4 (33.3%) categories had adherence rates ≥80%, 0 had rates from 60% to 79.9%, and 8 (66.7%) had rates ≤59.9%.

CONCLUSION

The overall mean adherence to MIBO guidelines by RCTs on PRP interventions for knee osteoarthritis was 53.1%. To increase the reproducibility, improve transparency, and assess the treatment efficacy of future PRP studies, reporting of MIBO guidelines should be improved.

Adipose-derived regenerative therapies for the treatment of knee osteoarthritis

Knee osteoarthritis is a degenerative condition with a significant disease burden and no disease-modifying therapy. Definitive treatment ultimately requires joint replacement. Therapies capable of regenerating cartilage could significantly reduce financial and clinical costs. The regenerative potential of mesenchymal stromal cells (MSCs) has been extensively studied in the context of knee osteoarthritis. This has yielded promising results in human studies, and is likely a product of immunomodulatory and chondroprotective biomolecules produced by MSCs in response to inflammation. Adipose-derived MSCs (ASCs) are becoming increasingly popular owing to their relative ease of isolation and high proliferative capacity. Stromal vascular fraction (SVF) and micro-fragmented adipose tissue (MFAT) are produced by the enzymatic and mechanical disruption of adipose tissue, respectively. This avoids expansion of isolated ASCs ex vivo and their composition of heterogeneous cell populations, including immune cells, may potentiate the reparative function of ASCs. In this editorial, we comment on a multicenter randomized trial regarding the efficacy of MFAT in treating knee osteoarthritis. We discuss the study's findings in the context of emerging evidence regarding adipose-derived regenerative therapies. An underlying mechanism of action of ASCs is proposed while drawing important distinctions between the properties of isolated ASCs, SVF, and MFAT.

How to explain the beneficial effects of platelet-rich plasma

Platelet-rich plasma (PRP) is the platelet and leukocyte-containing plasmatic fraction of anticoagulated autologous blood. While evidence supporting the clinical use of PRP in dentistry is low, PRP is widely used in sports medicine, orthopedics, and dermatology. Its beneficial activity is commonly attributed to the growth factors released from platelets accumulating in PRP; however, evidence is indirect and not comprehensive. There is thus a demand to revisit PRP with respect to basic and translational science. This review is to (i) recapitulate protocols and tools to prepare PRP; (ii) to discuss the cellular and molecular composition of PRP with a focus on platelets, leukocytes, and the fibrin-rich extracellular matrix of coagulated plasma; and finally (iii) to discuss potential beneficial effects of PRP on a cellular and molecular level with an outlook on its current use in dentistry and other medical fields.

Most Publications Regarding Platelet-Rich Plasma Use in the Knee Are From Asia, Investigate Injection for Osteoarthritis, and Show Outcome Improvement: A Scoping Review

PURPOSE

To evaluate and synthesize the available literature related to platelet-rich plasma (PRP) treatment of knee pathologies and to provide recommendations to inform future research in the field.

METHODS

PubMed, CINAHL, and Scopus databases were queried on October 6, 2023. All identified citations were collated and uploaded into Covidence for screening and data extraction. Studies were included if they were human studies published in English with adult cohorts that received PRP as a procedural injection or surgical augmentation for knee pathologies with patient-reported outcome measures (PROMs) and level of evidence Levels I-IV.

RESULTS

Our search yielded 2,615 studies, of which 155 studies from 2006 to 2023 met the inclusion criteria. Median follow-up was 9 months (±11.2 months). Most studies (75.5%) characterized the leukocyte content of PRP, although most studies (86%) did not use a comprehensive classification scheme. In addition, most studies were from Asia (50%) and Europe (32%) and were from a single center (96%). In terms of treatment, 74% of studies examined PRP as a procedural injection, whereas 26% examined PRP as an augmentation. Most studies (68%) examined treatment of knee osteoarthritis. Many studies (83%) documented significant improvements in PROMs, including 93% of Level III/IV evidence studies and 72% of Level I/II evidence studies, although most studies (70%) failed to include minimal clinically important difference values. The visual analog scale was the most-used PROM (58% of studies), whereas the Short Form Health Survey 36-item was the least-used PROM (5% of studies).

CONCLUSIONS

Most published investigations of knee PRP are performed in Asia, investigate procedural injection for osteoarthritis, and show significant outcome improvements. In addition, this review highlights the need for better classification of PRP formulations.

LEVEL OF EVIDENCE

Level IV, scoping Review of level I-IV studies.

Microfragmented Adipose Tissue Is Equivalent to Platelet-Rich Plasma for Knee Osteoarthritis at 12 Months Posttreatment: A Randomized Controlled Trial

Background

Platelet-rich plasma (PRP) is an effective treatment for knee osteoarthritis (OA). Microfragmented adipose tissue (MFAT) is another orthobiologic that holds promise, but data supporting its use are limited. Previous studies showed that MFAT created using the Lipogems device was equivalent to PRP created via noncommercial laboratory-based processes.

Purpose

To perform a comparison of commercially available MFAT and PRP systems for treatment of knee OA.

Study Design

Randomized controlled trial; Level of evidence, 2.

Methods

A total of 71 patients with symptomatic knee OA (Kellgren-Lawrence grades 1-4) were randomized to receive a single injection of either leukocyte-rich PRP (Angel; Arthrex) or MFAT (Lipogems) under ultrasound guidance. Patient-reported outcomes (Knee injury and Osteoarthritis Outcome Score [KOOS], visual analog scale for pain with activities of daily living [VAS pain], and Tegner activity level) were recorded at baseline and at 1, 3, 6, and 12 months after injection. The primary outcome was the KOOS-Pain subscale score at 12 months after injection.

Results

Overall, 49 patients completed their 12-month follow-up (PRP group, n = 23; MFAT group, n = 26). All demographic features were similar between groups, except that more men were randomized to the PRP group and more women to the MFAT group. At 12 months posttreatment, KOOS-Pain scores improved in both groups, with no significant group difference (PRP, 78 ± 17.9 vs MFAT, 77.8 ± 19.3; P = .69). Similarly, other KOOS subscales, VAS pain scores, and Tegner scores improved at 12 months, with no differences between treatment groups.

Conclusion

Both PRP and MFAT injections for knee OA resulted in improved patient-reported outcomes at 12 months posttreatment, with no differences found between treatments.

Registration

NCT04351087 (ClinicalTrials.gov identifier).

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.

Knee Osteoarthritis: Clinical and MRI Outcomes After Multiple Intra-Articular Injections With Expanded Autologous Adipose-Derived Stromal Cells or Platelet-Rich Plasma

OBJECTIVE

To directly compare clinical and MRI outcomes of multiple intra-articular injections of adipose-derived stromal cells (ASCs) or platelet-rich plasma (PRP) in patients with knee osteoarthritis (OA).

DESIGN

We retrospectively compared 24-month outcomes in (1) 27 patients receiving 3-monthly intra-articular injections with a total of 43.8 million ASCs and (2) 23 patients receiving 3-monthly injections of 3-ml preparation of PRP. All patients had Kellgren-Lawrence grade 1, 2, or 3 knee OA with failed conservative medical therapy. The Numeric Pain Rating Scale (NPRS) scores; Knee injury and Osteoarthritis Outcome Score (KOOS) at baseline, 6, 12, and 24 months after the first injection; and the MRI Osteoarthritis Knee Score (MOAKS) at 12 and 24 months were considered as outcomes.

RESULTS

No major complications occurred in any patient. Both groups significantly improved in pain NPRS score and KOOS at 6 months. At 12- and 24-month evaluations, the ASC group significantly decreased scores to a greater degree (P < 0.001) than the PRP group. MOAKS scores indicated a decrease in disease progression in the ASC group.

CONCLUSION

Both ASCs and PRP were safe and resulted in clinical improvement in patients with knee OA at 6 months; however, at 12 and 24 months, ASCs outperformed leukocyte-poor PRP in clinical and radiological outcomes.

Autologous micro-fragmented adipose tissue in the treatment of atherosclerosis patients with knee osteoarthritis in geriatric population: A systematic review and meta-analysis

BACKGROUND

Atherosclerosis and osteoarthritis are closely related. However, no high-quality studies have investigated the potential of micro-fragmented adipose tissue to treat patients with atherosclerosis accompanied by osteoarthritis.

METHODS

PubMed, Embase, the Cochrane Library, Web of Science, China National Knowledge Infrastructure, WANFANG DATA, and CQVIP were searched for potentially eligible studies published before October 13, 2022. Due to the statistical limitations of the existing relevant literature, it is not possible to make direct statistics on the patients with osteoarthritis accompanied by atherosclerosis treated by micro-fragmented adipose tissue. The primary outcome consisted of two parts: 1) Correlation between atherosclerosis and osteoarthritis; 2) Scores of the Knee injury and Osteoarthritis Outcome Score (KOOS). And secondary outcomes were pain assessed by visual analog scale (VAS) or numeric rating scale (NRS), quality of life (QoL) (assessed using tools apart from the KOOS), and adverse events (AEs). Random meta-analysis was conducted using STATA 14.0.

RESULTS

Nineteen studies were included. The metaanalysis evidenced a positive association between atherosclerosis and osteoarthritis (OR 1.17, CI 1.01-1.36). The mean absolute difference in KOOS subscale scores between pre- and post-treatment (mean with 95% confidence interval [CI]) was 19.65 (13.66, 25.63), 14.20 (4.64, 23.76), 19.95 (13.02, 26.89), 25.23 (14.80, 35.66), and 26.01 (13.68, 38.35) for pain, symptoms, activities of daily living (ADL), sports/recreation, and quality-of-life (QOL), respectively. The mean differences in VAS, resting VAS, activity VAS, and NRS between pre- and post-treatment was -8.24 (-10.66, -5.82), -3.61 (-4.49, -2.72), -4.17 (-4.89, -3.44), and -2.17 (-4.06, and -0.28), respectively. The mean difference in score of Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), EQ-5D, and University of California in Los Angeles (UCLA) between pre- and post-treatment was -24.81 (-40.80, -8.82), 0.07 (0.02, 0.12), and 0.30 (-0.42, 1.02), respectively. The mean difference in Tegner score and the International Knee Documentation Committee (IKDC) score between pre- and post-treatment was 0.67 (-0.62, 1.97) and 13.70 (6.35, 21.04), respectively. The use of micro-fragmented adipose tissue was associated with risk of bruising, bleeding, hematoma, drainage, infection, soreness, swelling, pain, and stiffness in harvest and injection sites.

CONCLUSION

Atherosclerosis and osteoarthritis share common risk factors and comorbidity. And the use of micro-fragmented adipose tissue may benefit for improving symptoms of knee osteoarthritis accompanied by atherosclerosis although may lead to some mild adverse events. Randomized controlled trials with long-term follow-up are necessary for further evaluation because many limitations of this meta-analysis cannot be ignored.