Bone Marrow Aspirate Concentrate for Orthopaedic Use

Safety and Efficacy of Bone-Marrow Aspirate Concentrate in Hip Osteoarthritis: A Systematic Review of Current Clinical Evidence

Introduction

Hip osteoarthritis (OA) is one of the leading causes of disability and morbidity worldwide. It is estimated to affect 9.2% individuals globally with age over 45 years. Conventional treatment modalities have limitations and side-effects. To overcome these limitations, over the last decade, there has been an increased interest in the use of orthobiologics derived from autologous sources including platelet-rich plasma (PRP), bone-marrow aspirate concentrate (BMAC) and adipose tissue derived formulations. This review qualitatively presents the in-vitro, pre-clinical, clinical and on-going clinical studies exploring the safety and efficacy of BMAC for management of hip OA.

Materials and methods

The electronic database search was done through PubMed, Embase, Web of Science, Scopus, ProQuest and Google Scholar till February 2024. The search terms used were "osteoarthritis" OR "hip osteoarthritis" OR "orthobiologics" OR "efficacy or use of orthobiologic treatment" OR "bone-marrow concentrate" OR "bone-marrow aspirate concentrate", AND "BMAC". The inclusion criteria were clinical studies of any level of evidence written in the English language, published till February 2024, evaluating the safety and efficacy of intra-articular administration of BMAC for the management of hip OA.

Results

A total of 5 studies were included in this review for qualitative data synthesis. The total number of patients who participated in the study was 182, ranging from 4 to 112 in a single study. No adverse events were reported throughout the duration of the study. In addition, intra-articular administration of BMAC led to reduced pain, and improved function and overall quality of life (QoL).

Conclusion

The results from this review demonstrated that administration of BMAC is safe and potentially efficacious in terms of reducing pain, improving function and overall QoL of patients with hip OA in short- and mid-term average follow-up based on the included studies. Nonetheless, more adequately powered, multi-center, prospective, double-blind, non-randomized and randomized controlled trials with long-term follow-up are warranted to establish long-term safety and efficacy of BMAC for management of hip OA and justify its routine clinical use.

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

LEVEL OF EVIDENCE

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

Preclinical Animal Study and Pilot Clinical Trial of Using Enriched Peripheral Blood-Derived Mononuclear Cells for Intervertebral Disc Degeneration

Low back pain (LBP) is a leading cause of long-term disability globally. Intervertebral disk degeneration (IVDD) is mainly responsible for discogenic pain in LBP-affected young patients. There is no effective therapy to reverse disease severity and IVDD progression. This study investigates the effect of human peripheral blood-derived mononuclear cells (PBMCs) on pain relief and life quality improvement in IVDD patients. The enriched monocytes of the PBMCs could differentiate into CD14 and CD206 double-positive M2 macrophages in vitro. Preclinical evidence in rats showed that the transplanted PBMCs exhibited anti-inflammatory and moderate tissue-repair effects on controlling IVDD progress in the rat model. The PBMCs significantly steered the aggrecan and type II collagen expressions and attenuated the pro-inflammatory cytokines in the affected disk. Based on the animal results, 36 patients with chronic low back pain (CLBP) were included in clinical trials. The control group was conservative care only, and the experimental group was platelet-rich plasma (PRP) and PBMCs intradiscal injections. We first confirmed the single lumbar disk causing the discogenic pain by provocative discography or magnetic resonance imaging (MRI). Discogenic LBP participants received one intradiscal injection of autologous PBMCs and followed for 6 months. Our clinical trial showed that patients' LBP and disability were significantly ameliorated after the PBMCs transplantation rather than PRP. These preclinical and pilot clinical studies indicate that intradiscal injection of the enriched PBMCs might be a feasible and potential cell therapy to control pain and disability in IVDD patients.

Patients With Knee Osteoarthritis Who Receive Platelet-Rich Plasma or Bone-Marrow Aspirate Concentrate Injections Have Better Outcomes Than Patients Who Receive Hyaluronic Acid: Systematic Review and Meta-analysis

PURPOSE

To systematically review the literature in order to compare the efficacy and safety of platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC), and hyaluronic acid (HA) injections for the treatment of knee osteoarthritis (OA).

METHODS

A systematic review was performed by searching PubMed, the Cochrane Library, and Embase to identify Level I studies that compared the clinical efficacy of at least 2 of the following 3 injection therapies: PRP, BMAC, and HA for knee OA. The search phrase used was knee AND osteoarthritis AND randomized AND ("platelet rich plasma" OR "bone marrow aspirate" OR "hyaluronic acid"). Patients were primarily assessed based on patient-reported outcome scores (PROs) including the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), visual analog scale (VAS) for pain, and Subjective International Knee Documentation Committee (IKDC) score.

RESULTS

Twenty-seven studies (all Level I) met inclusion criteria, including 1,042 patients undergoing intra-articular injection(s) with PRP (mean age 57.7 years, mean follow-up 13.5 months), 226 patients with BMAC (mean age 57.0 years, mean follow-up 17.5 months), and 1,128 patients with HA (mean age 59.0 years, mean follow-up 14.4 months). Non-network meta-analyses demonstrated significantly better post-injection WOMAC (p < 0.001), VAS (p < 0.01), and Subjective IKDC scores (p < 0.001) in PRP patients when compared to HA patients. Similarly, network meta-analyses demonstrated significantly better post-injection WOMAC (p < 0.001), VAS (p = 0.03), and Subjective IKDC (p < 0.001) scores in BMAC patients when compared to HA patients. There were no significant differences in post-injection outcome scores when comparing PRP to BMAC.

CONCLUSION

Patients undergoing treatment for knee OA with PRP or BMAC can be expected to experience improved clinical outcomes when compared to HA patients.

LEVEL OF EVIDENCE

I, Meta-Analysis of Level I studies.

Factors Influencing the Yield of Progenitor Cells in Bone Marrow Aspiration Concentrate—A Retrospective Analysis of 58 Patients

This study aims to identify the role of subjective factors (age, sex, and comorbidities) and procedure-specific factors (aspiration volume) in influencing the yield of progenitor cells in bone marrow aspiration concentrate (BMAC) harvested from the iliac crest. A retrospective analysis was conducted on 58 patients (male:female = 31:27; mean age: 52.56 ± 18.14 years) who underwent BMAC therapy between January 2020 and June 2021. The factors analyzed include individual factors such as age, sex, and comorbid conditions, and procedural factors such as aspirate volume. The mononuclear cell (MNC) count and colony-forming unit (CFU) assay were used to assess the yield of progenitors in the aspirate. Pearson’s correlation test was performed for the age, aspirate volume, and outcome parameters, such as MNC and CFU. We used the chi-square test to analyze the role of sex and comorbidities on cellular yield. The mean volume of aspirate used for BMAC therapy was 66.65 (±17.82) mL. The mean MNC count of the BMAC was 19.94 (±16.34) × 106 cells, which formed 11 (±12) CFUs. Evidence of statistically significant positive associations was noted between the CFUs developed from the BMAC and the MNC count within them (r = 0.95, p < 0.001). The sex of the individual did not play any significant role in MNC count (p = 0.092) or CFUs formed (p = 0.448). The age of the individual showed evidence of a statistically significant negative association with the MNC count (r = −0.681, p < 0.001) and CFUs (r = −0.693, p < 0.001), as did the aspiration volume with the MNC count (r = −0.740, p < 0.001) and CFUs (r = −0.629, p < 0.001). We also noted a significant reduction in the MNC count (p = 0.002) and CFUs formed (p = 0.004) when the patients presented comorbidities. Individual factors such as age, comorbid conditions, and procedure factors such as aspirate volume significantly affected the yield of progenitor cells in the BMAC. The sex of the individual did not influence the yield of progenitor cells in BMAC.

Prospective Randomized Trial of Biologic Augmentation With Bone Marrow Aspirate Concentrate in Patients Undergoing Arthroscopic Rotator Cuff Repair

BACKGROUND

Although initial studies have demonstrated that concentrated bone marrow aspirate (cBMA) injections promote rotator cuff repair (RCR) healing, there are no randomized prospective studies investigating clinical efficacy.

HYPOTHESIS/PURPOSE

To compare outcomes after arthroscopic RCR (aRCR) with and without cBMA augmentation. It was hypothesized that cBMA augmentation would result in statistically significant improvements in clinical outcomes and rotator cuff structural integrity.

STUDY DESIGN

Randomized controlled trial; Level of evidence, 1.

METHODS

Patients indicated for aRCR of isolated 1- to 3-cm supraspinatus tendon tears were randomized to receive adjunctive cBMA injection or sham incision. Bone marrow was aspirated from the iliac crest, concentrated using a commercially available system, and injected at the aRCR site after repair. Patients were assessed preoperatively and serially until 2 years postoperatively via the following functional indices: American Shoulder and Elbow Surgeons (ASES), Single Assessment Numeric Evaluation (SANE), Simple Shoulder Test, 12-Item Short Form Health Survey, and Veterans RAND 12-Item Health Survey. Magnetic resonance imaging (MRI) was performed at 1 year to assess rotator cuff structural integrity according to Sugaya classification. Treatment failure was defined as decreased 1- or 2-year ASES or SANE scores as compared with preoperative baseline, the need for revision RCR, or conversion to total shoulder arthroplasty.

RESULTS

An overall 91 patients were enrolled (control, n = 45; cBMA, n = 46): 82 (90%) completed 2-year clinical follow-up and 75 (82%) completed 1-year MRI. Functional indices significantly improved in both groups by 6 months and were sustained at 1 and 2 years (all P < .05). The control group showed significantly greater evidence of rotator cuff retear according to Sugaya classification on 1-year MRI (57% vs 18%; P < .001). Treatment failed for 7 patients in each group (control, 16%; cBMA, 15%).

CONCLUSION

cBMA-augmented aRCR of isolated supraspinatus tendon tears may result in a structurally superior repair but largely fails to significantly improve treatment failure rates and patient-reported clinical outcomes when compared with aRCR alone. Additional study is warranted to investigate the long-term benefits of improved repair quality on clinical outcomes and repair failure rates.

REGISTRATION

NCT02484950 (ClinicalTrials.gov identifier).

Enriched Peripheral Blood-Derived Mononuclear Cells for Treating Knee Osteoarthritis

Osteoarthritis (OA) is a common chronic skeletal disease in the elderly. There is no effective therapy to reverse disease severity and knee OA (KOA) progression, particularly at the late stage. This study aims to examine the effect of peripheral blood-derived mononuclear cells (PBMNCs) on pain and motor function rescue in patients with Kellgren-Lawrence (KL) grade II to IV KOA. Participants received one intra-articular (IA) injection of autologous PBMNCs. The mononuclear cells were isolated from peripheral blood, enriched by a specialized medium (MoFi medium), and separated by Ficoll-Paque solution. The isolated and enriched PBMNCs could differentiate into M1 and M2 macrophages in vitro. The in vivo anti-inflammatory effect of the PBMNCs was similar to that of bone marrow mesenchymal stem cells, evaluated by complete Freund's adjuvant-induced arthritis in rodents. A single-arm and open-label pilot study showed that patients' knee pain and motor dysfunction were significantly attenuated after the cell transplantation, assessed by visual analogue scale (VAS) and Knee injury and Osteoarthritis Outcome Score (KOOS) at 6 and 12 months post-treatment. Notably, the therapeutic effect of the PBMNCs treatment can be stably maintained for 24 months, as revealed by the KOOS scores. These preclinical and pilot clinical data suggest that IA injection of MoFi-PBMNCs might serve as a novel medical technology to control the pain and the progress of KOA.

The use of biologics to improve patient-reported outcomes in hip preservation

Despite lack of clear understanding, the use of biologic treatment methods has increased in the United States. Therapeutic methods, including platelet-rich plasma (PRP), bone marrow aspirate concentrate (BMAC) and hyaluronic acid (HA) among other biologics, are commonly associated with relief of pain in a number of different orthopedic conditions. Within the past two decades, hip preservationists have investigated the roles of these biologic treatments in both non-operative and surgical management of common hip conditions. The purpose is to review the published literature surrounding the application and efficacy of biologics, most notably PRP, BMAC and HA, in the clinical management of hip conditions. The hip conditions examined in this review include hip osteoarthritis, femoroacetabular impingement syndrome and associated labral tear pathology, avascular necrosis of the femoral head and gluteal/hamstring tendinopathy. While our review of the literature suggests that there is support for the implementation of biologics to relieve pain and improve function for hip conditions. Through further research efforts, it is important to stay updated with the clinical efficacy of biologics in hip preservation.

Bone Marrow Concentrate Injection Treatment Improves Short-term Outcomes in Symptomatic Hip Osteoarthritis Patients: A Pilot Study

BACKGROUND

Osteoarthritis (OA) is one of the leading causes of disability in the United States, the hip being the second most affected weightbearing joint. Autologous bone marrow concentrate (BMC) is a promising alternative therapy to conventional treatments, with the potential to mitigate inflammation and improve joint function.

PURPOSE

To investigate the effectiveness of a single intra-articular BMC injection for patients with symptomatic hip OA.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 24 patients diagnosed with symptomatic hip OA who elected to undergo a single BMC injection were prospectively enrolled in the study. Patients were excluded if they reported a preinjection Numeric Rating Scale (NRS) score for pain with activity of <6 points out of 10. The Western Ontario and McMaster Universities Arthritis Index (WOMAC), modified Harris Hip Score (mHHS), Hip Outcome Score-Activities of Daily Living (HOS-ADL), 12-Item Short Form Health Survey (SF-12), and NRS pain scores were collected before and after the procedure (6 weeks, 3 months, and 6 months). Joint space and Tönnis OA grade scores were recorded on preinjection anteroposterior pelvis radiographs.

RESULTS

A total of 18 hips from 16 patients (7 male and 9 female) (mean age, 57.6 ± 11; mean body mass index, 25.9 ± 3.6 kg/m2) were used in the final analysis. Significant improvements were observed in NRS pain with activity (from 8 to 4.5; P < .001) and without activity (from 5 to 1; P < .001), WOMAC (from 31 to 16; P = .006), mHHS (from 63 to 80; P = .004), and HOS-ADL (from 71 to 85; P = .014) over 6 months. At 6 months, all patients maintained their improvements and did not return to preprocedure status. BMI significantly correlated with baseline WOMAC scores (P = .012) and inversely correlated with 6-month SF-12 Physical Component Summary (P = .038). Tönnis grades 2 and 3 were inversely correlated with 6-week SF-12 Mental Component Summary (P = .008) and 3-month pain with activity (P = .032). No serious adverse events were reported from the BMC harvest or injection procedure.

CONCLUSION

A single BMC injection can significantly improve subjective pain and function scores up to 6 months in patients with symptomatic hip OA. Further studies are warranted to evaluate BMC treatment against other therapeutics in a larger sample size and compare the biological signature profiles that may be responsible for the therapeutic effect.

Effect of Oral Losartan on Orthobiologics: Implications for Platelet-Rich Plasma and Bone Marrow Concentrate-A Rabbit Study

Recent efforts have focused on customizing orthobiologics, such as platelet-rich plasma (PRP) and bone marrow concentrate (BMC), to improve tissue repair. We hypothesized that oral losartan (a TGF-β1 blocker with anti-fibrotic properties) could decrease TGF-β1 levels in leukocyte-poor PRP (LP-PRP) and fibrocytes in BMC. Ten rabbits were randomized into two groups (N = 5/group): osteochondral defect + microfracture (control, group 1) and osteochondral defect + microfracture + losartan (losartan, group 2). For group 2, a dose of 10mg/kg/day of losartan was administrated orally for 12 weeks post-operatively. After 12 weeks, whole blood (WB) and bone marrow aspirate (BMA) samples were collected to process LP-PRP and BMC. TGF-β1 concentrations were measured in WB and LP-PRP with multiplex immunoassay. BMC cell populations were analyzed by flow cytometry with CD31, CD44, CD45, CD34, CD146 and CD90 antibodies. There was no significant difference in TGF-β1 levels between the losartan and control group in WB or LP-PRP. In BMC, the percentage of CD31+ cells (endothelial cells) in the losartan group was significantly higher than the control group (p = 0.008), while the percentage of CD45+ cells (hematopoietic cells-fibrocytes) in the losartan group was significantly lower than the control group (p = 0.03).