Bone Marrow Aspirate Concentrate Harvesting and Processing Technique

Enhancing Cartilage Repair: Surgical Approaches, Orthobiologics, and the Promise of Exosomes

Treating cartilage damage is challenging as its ability for self-regeneration is limited. Left untreated, it can progress to osteoarthritis (OA), a joint disorder characterized by the deterioration of articular cartilage and other joint tissues. Surgical options, such as microfracture and cell/tissue transplantation, have shown promise as techniques to harness the body's endogenous regenerative capabilities to promote cartilage repair. Nonetheless, these techniques have been scrutinized due to reported inconsistencies in long-term outcomes and the tendency for the defects to regenerate as fibrocartilage instead of the smooth hyaline cartilage native to joint surfaces. Orthobiologics are medical therapies that utilize biologically derived substances to augment musculoskeletal healing. These treatments are rising in popularity because of their potential to enhance surgical standards of care. More recent developments in orthobiologics have focused on the role of exosomes in articular cartilage repair. Exosomes are nano-sized extracellular vesicles containing cargo such as proteins, lipids, and nucleic acids, and are known to facilitate intercellular communication, though their regenerative potential still needs to be fully understood. This review aims to demonstrate the advancements in cartilage regeneration, highlight surgical and biological treatment options, and discuss the recent strides in understanding the precise mechanisms of action involved.

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

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

Current Review of Regenerative Medicine Therapies for Spine-Related Pain

PURPOSE OF REVIEW

Persistent spinal pain syndromes are pervasive and lead to functional impairment, increased healthcare utilization, potential disability, and high societal costs. Spinal (cervical, thoracic, lumbar, and sacroiliac joint) pain includes mechanical, degenerative, inflammatory, oncologic, and infectious etiologies. Regenerative medicine is a novel biotechnology targeting mechanical, degenerative, and inflammatory conditions believed to cause pain. Preparations including platelet-rich plasma, mesenchymal stem cells (adipose tissue and bone marrow aspirate concentrates), and growth factors are derived from an autologous donor. The goal of intervention through guided injection of the regenerative media is to reduce inflammation and reverse the degenerative cascade in hopes of restoring normal cellular composition (physiologic homeostasis) and anatomical function to improve pain and function. The authors review limited research supporting the use of platelet-rich plasma injections for facet joint arthropathy and sacroiliac joint pain compared to traditional steroid treatments, as well as the use of platelet rich plasma or mesenchymal stem cells for lumbar discogenic and radicular pain.

RECENT FINDINGS

Current evidence to support regenerative medicine for spine-related pain is limited. Although several studies demonstrated a reduction in pain, many of these studies had a small number of participants and were case series or prospective trials. Regenerative medicine treatments lack evidence for the treatment of spine-related pain. Large randomized controlled trials are needed with consistent study protocols to make further recommendations.

Efficacy of using autologous cells with graft substitutes for spinal fusion surgery: A systematic review and meta-analysis of clinical outcomes and imaging features

Over the past several decades, there has been a notable increase in the total number of spinal fusion procedures worldwide. Advanced spinal fusion techniques, surgical approaches, and new alternatives in grafting materials and implants, as well as autologous cellular therapies, have been widely employed for treating spinal diseases. While the potential of cellular therapies to yield better clinical results is appealing, supportive data are needed to confirm this claim. This meta-analysis aims to compare the radiographic and clinical outcomes between graft substitutes with autologous cell therapies and graft substitutes alone. PubMed, Scopus, Web of Science, ClinicalTrials.gov, and the Cochrane Central Register of Controlled Trials were searched for studies comparing graft substitutes with autologous cell therapies and graft substitutes alone up to February 2024. The risk of bias of the included studies was evaluated using the Downs and Black checklist. The following outcomes were extracted for comparison: fusion success, complications/adverse events, Visual Analog Scale (VAS) score, and Oswestry Disability Index (ODI) score. Thirteen studies involving 836 patients were included, with 7 studies considered for the meta-analysis. Results indicated that the use of graft substitutes with autologous cell therapies demonstrated higher fusion success rates at 3, 6, and 12 months, lower VAS score at 6 months, and lower ODI score at 3, 6, and 12 months. The complication rate was similar between graft substitutes with autologous cell therapies and graft substitutes alone. Although the current literature remains limited, this meta-analysis suggests that the incorporation of cellular therapies such as bone marrow and platelet derivatives with graft substitutes is associated with a higher fusion rate and significant improvements in functional status and pain following spinal fusion. Future well-designed randomized clinical trials are needed to definitively assess the clinical effectiveness of cellular therapies in spinal fusion.

Core Decompression with Bone Marrow Aspirate Concentrate Implantation in Osteonecrosis of the Femoral Head with a Minimum of 2-year Follow-up - A Pilot Study

Introduction

Osteonecrosis of the femoral head (ONFH), resulting from impaired blood supply to the head of the femur, presents a significant challenge to clinicians due to its debilitating nature. Conservative treatment often offers insufficient pain relief and debilitating functional outcomes which necessitate alternative therapies. Bone marrow aspirate concentrate (BMAC), a potent orthobiologics and rich in mesenchymal stromal cells and growth factors, holds good promise as the minimally invasive procedure for ONFH. With the preceding research suggesting clinical and functional efficacy, we assessed the therapeutic effectiveness of BMAC in ONFH management in joint preservation.

Materials and Methods

A prospective cohort study was conducted with 20 patients suffering from ONFH who failed to respond to 6 months of conservative treatment. A uniform surgical procedure was performed by a single surgeon, involving bone marrow extraction from the anterior iliac crest and subsequent processing into an 8-10 mL of BMAC concentrate. The BMAC was then injected into the implanted into the decompressed femoral head. The post-operative protocol comprised weight-bearing mobilization, physiotherapy, and a 4-week NSAID-free regimen. Outcome measures included pain scores, hip function, knee symptoms, sports activities, patient satisfaction, and recommendation of the procedure.

Results

Of the 20 patients suffering from ONFH, primarily the left side, most of whom were at stage 2b, significant pain reduction and functional improvement were observed over 24 months. The mean pain score decreased from 9.00 to 3.55, while the hip function score increased from 46.12 to 88.60. However, some patients encountered complications such as symptom recurrence (5%), disease progression (10%), and persistent pain (5%).

Conclusion

Core decompression with BMAC implantation emerges as a promising, effective, and safe treatment for ONFH with better costeffectiveness and minimal side effects, making it a feasible treatment alternative.

Effect of Cellular Dosage of Bone Marrow Aspiration Concentrate on the Radiological Outcomes in Knee Osteoarthritis: A Phase I Dose-Escalation Study

Introduction

Knee osteoarthritis(KOA), a chronic degenerative disease, significantly impairs quality of life due to pain and mobility limitations. Traditional treatments focus on symptom management without addressing the underlying disease progression, leading to a growing interest in regenerative medicine approaches. Bone marrow aspirate concentrate (BMAC), rich in mesenchymal stem cells and growth factors, has shown potential for cartilage repair and symptom relief in KOA. Despite promising outcomes, the optimal BMAC dosage for knee OA treatment remains undetermined. This study aims to evaluate the radiological outcomes of varying BMAC dosages in knee OA treatment.

Methods

This prospective controlled dose-escalation study involved 75 patients with early-stage knee OA, categorized into three groups based on BMAC dosage administered 10x106 cells (low-dose group), 50 × 106 cells (medium-dose group), or 100x106 cells (high-dose group). All the patients underwent a single intra-articular injection of BMAC and were monitored over a year. The primary outcomes include magnetic resonance observation of cartilage repair tissue (MOCART 2.0) score to assess the cartilage.

Results

We noted significant improvement in the overall MOCART score (p = 0.027) and subchondral change sub-score (p = 0.048) and defect filling sub-score (p = 0.025) in the medium- and high-dose cohorts compared to the low-dose cohort at 1 year follow-up. Although we noted positive correlation between the clinical and radiological outcome (r = 0.43), we did not find any significant different in the clinical outcome between the treatment groups.

Conclusion

BMAC for OA knee resulted in significant improvement in the radiological scores compared to the baseline. Medium and high doses of BMAC result in significantly higher radiological scores compared to low-dose BMAC at 1 year. However, the radiological improvement did not translate into functional improvement, irrespective of the dosage administered at 1 year. Further research is necessary on the long-term outcomes to understand and optimize the dosing strategy based on clinico-radiological results.

Increased Cellular Dosage of Bone Marrow Aspiration Concentrate Does Not Translate to Increased Clinical Effectiveness in Knee Osteoarthritis: A Phase I Dose Escalation Study

Introduction

Knee osteoarthritis (KOA), a chronic degenerative disease, significantly impairs quality of life due to pain and mobility limitations. Traditional treatments focus on symptom management without addressing the underlying disease progression, leading to a growing interest in regenerative medicine approaches. Bone marrow aspirate concentrate (BMAC), rich in mesenchymal stem cells and growth factors, has shown potential for cartilage repair and symptom relief in KOA. Despite promising outcomes, the optimal BMAC dosage for knee OA treatment remains undetermined. This study aims to evaluate the clinical efficacy and safety of varying BMAC dosages in knee OA treatment.

Methods

This prospective controlled dose-escalation study involved 75 patients with early-stage knee OA, categorized into three groups based on BMAC dosage administered 10 × 106 cells (low-dose group), 50 × 106 cells (medium-dose group), or 100 × 106 cells (high-dose group). All the patients underwent a single intra-articular injection of BMAC and were monitored over a year. The primary outcomes include Visual Analog Scale (VAS) for pain and the Knee Injury and Osteoarthritis Outcome Score (KOOS) for joint function recorded at baseline, 1, 3, 6, and 12 months post-intervention. Adverse events were also documented.

Results

Significant clinical improvements in VAS and KOOS scores were noted across all groups at all time points compared to the baseline. However, these improvements did not significantly differ between dosage groups throughout the follow-up period. Adverse effects were minimal and primarily consisted of transient post-injection pain and effusion, with no dose-dependent increase in complications.

Conclusion

BMAC treatment for knee OA is safe and demonstrates potential for significant pain relief and functional improvement, irrespective of the dosage administered within the tested range. The lack of significant differences among varying dosages suggests a plateau in therapeutic efficacy beyond a certain threshold. Further research is necessary on the long-term outcomes to optimize the dosing strategy.

Improving Fertility in Non-obstructive Azoospermia: Results from an Autologous Bone Mar-row-Derived Mesenchymal Stromal/Stem Cell Phase I Clinical Trial

BACKGROUND

In this phase I clinical trial, our primary objective was to develop an innovative therapeutic approach utilizing autologous bone marrow-derived mesenchymal stromal/stem cells (BM-MSCs) for the treatment of nonobstructive azoospermia (NOA). Additionally, we aimed to assess the feasibility and safety of this approach.

MATERIALS AND METHODS

We recruited 80 participants in this non-randomized, open-label clinical trial, including patients undergoing NOA treatment using autologous BM-MSCs (n=40) and those receiving hormone therapy as a control group (n=40). Detailed participant characteristics, such as age, baseline hormonal profiles, etiology of NOA, and medical history, were thoroughly documented. Autotransplantation of BM-MSCs into the testicular network was achieved using microsurgical testicular sperm extraction (microTESE). Semen analysis and hormonal assessments were performed both before and six months after treatment. Additionally, we conducted an in-silico analysis to explore potential protein-protein interactions between exosomes secreted from BM-MSCs and receptors present in human seminiferous tubule cells.

RESULTS

Our results revealed significant improvements following treatment, including increased testosterone and inhibin B levels, elevated sperm concentration, and reduced levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and prolactin. Notably, in nine patients (22.5%) previously diagnosed with secondary infertility and exhibiting azoospermia before treatment, the proposed approach yielded successful outcomes, as indicated by hormonal profile changes over six months. Importantly, these improvements were achieved without complications. Additionally, our in-silico analysis identified potential binding interactions between the protein content of BM-MSC-derived exosomes and receptors integral to spermatogenesis.

CONCLUSION

Autotransplantation of BM-MSCs into the testicular network using microTESE in NOA patients led to the regeneration of seminiferous tubules and the regulation of hormonal profiles governing spermatogenesis. Our findings support the safety and effectiveness of autologous BM-MSCs as a promising treatment modality for NOA, with a particular focus on the achieved outcomes in patients with secondary infertility (registration number: IRCT20190519043634N1).

Bone Marrow Aspirate Concentrate for Treatment of Primary Knee Osteoarthritis: A Prospective, Single-Center, Non-randomized Study with 2-Year Follow-Up

Introduction

Knee osteoarthritis (OA) is a widespread, disabling condition with no intervention to fully restore cartilage or halt progression. Bone marrow aspirate concentrate (BMAC), an autologous product from bone marrow aspiration, has shown promise as a regenerative therapy due to its cell composition and chondrogenic effects. Our study aims to assess the functional outcomes, including pain, function, satisfaction, and complications post-BMAC injection in knee OA patients.

Materials and Methods

In this prospective, single-center study, 63 patients with grade II-III knee OA (Kellgren-Lawrence (K-L) scale) unresponsive to conservative management underwent BMAC injection. The procedure involved bone marrow aspiration from the anterior iliac crest, processing to obtain a concentrate, followed by intra-articular injection. Patients were followed for 24 months, assessing outcomes using the Visual Analog Scale (VAS), International Knee Documentation Committee (IKDC) score, and MOCART 2.0 score.

Results

The cohort, with a slight female predominance and predominantly aged 41-50 years, majorly comprised K-L grade III OA patients. BMAC treatment resulted in significant improvements in VAS pain scores, IKDC functional scores, and MOCART 2.0 scores over the 24-month follow-up.

Conclusion

BMAC injection provides significant improvement in both pain and functional outcomes at mid-term follow-up in patients with mild-to-moderate OA of the knee. Further high-quality, adequately powered, multi-center, prospective, double-blinded, randomized controlled trials with longer follow-up are necessary to justify the routine clinical use of BMAC for treatment of patients suffering with knee OA.

Graphical Abstract

Effectiveness and Complications of Bone Marrow Aspirate Concentrate in Patients with Knee Osteoarthritis of Kellgren-Lawrence Grades II-III

This study aimed to identify the effectiveness and potential complications on the harvest site and knee of bone marrow aspirate concentrate (BMAC) treatment of patients with Kellgren-Lawrence (K-L) grades II-III knee osteoarthritis (OA) over a minimum follow-up period of 6 months. This study retrospectively evaluated data from 231 patients (285 knees) with knee OA treated with BMAC articular injection at a single center from August 2023 to October 2023. The inclusion criteria were a longstanding knee pain unresponsive to conservative treatments for at least 6 weeks with K-L grades II-III OA. The exclusion criteria were age of <40 years or >80 years, previous knee surgery, rheumatological or other systemic disease, malignancy, uncontrolled diabetes mellitus, or infections. Bone marrow was aspirated from the anterior iliac crest and concentrated by the single-spin centrifugation technique. The visual analog scale (VAS) pain score and Knee Society Score were used to evaluate the clinical outcomes and complications associated with harvest and injection sites were evaluated. The mean follow-up period was 7.2 months (range: 6-8 months). The pretreatment VAS pain score decreased from 4.3 to 0.4 points at the final follow-up (p < 0.05). Pretreatment Knee Society knee and function scores were improved from 86.9 to 98.1 (p < 0.05) and from 68.4 to 83.3 points (p < 0.05), respectively. A total of 15 complications (5.3%, 15/285) were observed, including 3 hematomas, 2 numbness, 2 contact dermatitis, and 1 superficial infection in the harvest site and 4 mild and moderate swelling and 3 severe swelling and pain in the injection site. BMAC is a reliable and effective treatment for patients with K-L grades II-III knee OA, but the orthopedic surgeon should consider that bleeding tendency by heparin causes severe joint swelling and pain after intra-articular knee injection.

A New Approach to Postoperative Rehabilitation following Mosaicplasty and Bone Marrow Aspiration Concentrate (BMAC) Augmentation

BACKGROUND

Chondral defects in the knee present a significant challenge due to their limited self-healing capacity, often leading to joint degeneration and functional disability. Current treatments, including surgical approaches like mosaicplasty and regenerative therapies such as bone marrow aspirate concentrate (BMAC) augmentation, aim to address these defects and improve patient outcomes.

MATERIALS AND METHODS

This study conducted a single-center, randomized controlled trial to evaluate the efficacy of different treatment approaches and rehabilitation protocols for chondral defects. Thirty-seven subjects presenting with symptomatic chondral or osteochondral defects (>3 cm2) in the weight-bearing region of the femoral condyle were partitioned into three groups, and underwent mosaicplasty with or without BMAC augmentation, followed by either a 6-week or 12-week rehabilitation program. Group 1 (n = 10) received mosaicplasty combined with BMAC augmentation and engaged in a twelve-week two-phase rehabilitation protocol. Group 2 (n = 15) underwent mosaicplasty alone and participated in the same twelve-week two-phase rehabilitation regimen. Meanwhile, Group 3 (n = 12) underwent mosaicplasty and underwent a shorter six-week one-phase rehabilitation program. Clinical assessments were performed using the visual analog scale (VAS) for pain, goniometry for the knee's range of motion (ROM), manual muscle testing (MMT) for quadricep strength, and the Western Ontario and McMaster University Arthritis Index (WOMAC) for functional evaluation in three test phases.

RESULTS

Significant differences in WOMAC scale scores were observed between the three groups at the intermediate (F(2, 34) = 5.24, p < 0.010) and final (F(2, 34) = 111, p < 0.000) stages, with post hoc Tukey tests revealing variations shared among all three groups. The between-group analysis of the VAS scale demonstrated no statistically significant difference initially (F(2, 34) = 0.18, p < 0.982), but significant differences emerged following the intermediate (F(2, 34) = 11.40, p < 0.000) and final assessments (F(2, 34) = 59.87, p < 0.000), with post hoc Tukey tests revealing specific group variations, notably between Group 1 and both Group 2 and Group 3, and also between Group 3 and Group 2. The between-group analysis of quadricep muscle strength using MMT scores revealed no statistically significant differences initially (F(2, 34) = 0.376, p < 0.689) or following the intermediate assessment (F(2, 34) = 2.090, p < 0.139). The one-way ANOVA analysis showed no significant difference in the knee ROM initially (F(2, 34) = 1.037, p < 0.366), but significant differences emerged following intermediate (F(2, 34) = 9.38, p < 0.001) and final assessments (F(2, 34) = 11.60, p < 0.000). Post hoc Tukey tests revealed significant differences between Groups 1 and 2, Groups 1 and 3, and Groups 2 and 3 at intermediate and final assessments.

CONCLUSIONS

The patients who received BMAC augmentation and completed a 12-week rehabilitation protocol had significantly better outcomes in pain relief, knee function, and ROM when compared to those who did not receive BMAC augmentation or those who completed a shorter rehabilitation period. Our findings suggest that combining mosaicplasty with BMAC augmentation and a comprehensive rehabilitation program can lead to superior clinical outcomes for patients with chondral defects in the knee.

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.

Biologic therapies in stress fractures: Current concepts

Stress fractures, a common overuse injury in physically active individuals, present a significant challenge for athletes and military personnel. Patients who sustain stress fractures have demanding training regimes where periods of rest and immobilisation have unacceptable negative consequences on sports goals and finances. Aside from being an overuse injury, there are various contributing risk factors that put certain individuals at risk of a stress fracture. The main two being nutritional deficiencies and hormonal variations, which have significant effects on bone metabolism and turnover. Historically, treatment of stress fractures focused on conservative strategies such as rest and immobilisation. Calcium and vitamin D deficiencies have been closely linked to stress fractures and so over time supplementation has also played a role in treatment. With the introduction of biologics into orthopaedics, newer treatment strategies have been applied to accelerate fracture healing and perhaps improve fracture callus quality. If such therapies can reduce time spent away from sport and activity, it would be ideal for treating stress fractures. This article aims to offer insights into the evolving landscape of stress fracture management. It investigates the pre-clinical evidence and available published clinical applications. Though fracture healing is well understood, the role of biologics for fracture healing is still indeterminate. Available literature for the use of biologic therapies in stress fractures are restricted and most reports have used biologics as a supplement to surgical fixation in subjects in studies that lack control groups. Randomised control trials have been proposed and registered by a few groups, with results awaited. Assessing individuals for risk factors, addressing hormonal imbalances and nutritional deficiencies seems like an effective approach to addressing the burden of stress fractures. We await better designed trials and studies to accurately determine the clinical benefit of adding biologics to the management of these injuries.

Using Computed Tomography-Based Three-dimensional Modeling and Computer Navigation for Minimally Invasive Core Decompression and Adjuvant Orthobiologic Therapy of Femoral Head Avascular Necrosis

Avascular necrosis of the femoral head is a debilitating condition that can lead to femoral head collapse. Core decompression with adjuvant cellular therapies, such as bone marrow aspirate concentrate, delays disease progression and improves outcomes. However, inconsistent results in the literature may be due to limitations in surgical technique and difficulty in targeting the necrotic lesions. Here, we present a surgical technique utilizing computed tomography-based three-dimensional modeling and instrument tracking to guide the therapy to the center of the lesion. This method minimizes the number of attempts to reach the lesion and confirms the three-dimensional positioning of the instrumentation within the lesion. Our technique may improve the outcomes of core decompression and adjuvant therapy and prevent or delay hip collapse in patients with femoral head avascular necrosis.

Bone Marrow Aspirate Concentrate Harvest Techniques for the Sports Medicine Surgeon

The use of bone marrow aspirate concentrate (BMAC) as a surgical augment to enhance biologic healing has been gaining popularity in a variety of sports medicine procedures. Due to its reliable availability from multiple sites, including the proximal tibia, proximal humerus, and anterior superior iliac spine, BMAC can be harvested at a location selected to be adjacent to the primary procedure. This Technical Note aims to highlight 3 different harvest sites for BMAC, allowing orthopaedic sports medicine surgeons to localize their harvest site based on the proximity of the planned procedure and ultimately increase efficiency.

Pain and Complications Following Bone Marrow Aspirate Concentrate Harvested From the Iliac Crest in Foot and Ankle Surgery

BACKGROUND

Autologous bone graft is the gold standard in orthopedics, with the iliac crest the most common harvest site. In an attempt to minimize morbidity with open bone graft harvest from the iliac crest and still maintain the benefit of collecting and transplanting live cells and growth factors, bone marrow aspirate concentrate (BMAC) from the iliac crest has become increasingly popular. However, any harvest procedure can potentially cause pain and complications. The purpose of this study was to evaluate the safety and complications of BMAC from the iliac crest for use in foot and ankle fusion procedures.

METHODS

A retrospective chart review was performed on all patients who underwent BMAC harvest from the iliac crest with their foot or ankle procedure by 1 of 4 fellowship-trained surgeons (2014-2017) with a minimum of 6-month follow-up. Patients were evaluated for complications, pain, and functional limitation secondary to the harvest. The final outcome follow-up was conducted using a specifically designed telephone questionnaire to assess patient satisfaction. A total of 55 patients were included, with a median age of 58 years (range 31-81 years) and 69% were women.

RESULTS

Out of 55 patients, 52 (94.5%) reported good to excellent results, and satisfaction with the procedure at the time of the questionnaire. Three patients reported persistent complications and some element of dissatisfaction after 6 months. Some patients reported transient complications (hematomas and numbness) that eventually resolved. Fifty percent of patients reported some element of immediate post-operative pain. However, at the time of final follow-up, only 2 reported persistent pain at the harvest site lasting up to 6 months, but it was not activity limiting.

CONCLUSION

BMAC harvest is a safe procedure with a high rate of patient satisfaction and minimal morbidity.

LEVELS OF EVIDENCE

Level IV: Case series.

Bone marrow aspirate concentrate - A novel approach to alter the course of temporomandibular joint osteoarthritis (a clinical study)

INTRODUCTION

TMJ OA is characterized by severe osteocartilaginous degradation of the joint structure resulting in severe deterioration of both joint function as well as joint structure. bone marrow aspirate concentrate (BMAC) gained wide acceptance as an auspicious addition for regenerative medicine as it is confirmed to be a rich source of pluripotent mesenchymal stem cells and growth factors that produce promising relief of clinical symptoms with significant repair of the joint structure. Thus, the study aims at assessing the efficacy of bone marrow aspirate concentrate (BMAC) as a treatment modality for TMJ osteoarthritis and compare its efficacy with that of hyaluronic acid (HA).

METHODS

24 patients were included in the present study and divided into 12 patients in each group. Joint arthrocentesis was performed to all patients followed by intra-articular BMAC injection in Group I. While Group II received HA acid injection RESULTS: A trend towards long term joint repair at 12 and 18 months follow up period was observed in the bone marrow aspirate concentrate (BMAC) group as a therapeutic modality for TMJ OA by providing necessary growth factors and anti-inflammatories that impedes the progression of the osteoarthritic degeneration. On the contrary to the viscosupplementary action of hyaluronic acid (HA) that showed relapse of patients conditions.

CONCLUSION

Bone marrow aspirate concentrate (BMAC) is able to reverse the degenerative effects of TMJ OA however,further studies are mandatory with larger population and longer follow-up time.

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

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

Combinatorial Influence of Bone Marrow Aspirate Concentrate (BMAC) and Platelet-Rich Plasma (PRP) Treatment on Cutaneous Wound Healing in BALB/c Mice

Bone marrow, a soft spongy tissue, is containing mesenchymal stem cells, that are well-recognized according to their self-renewability and stemness. Therefore, we hypothesized that bone marrow aspirate concentrate (BMAC) could have a pivotal influence on the process of wound healing in particular when it is combined with platelet-rich plasma (PRP). Thirty-six albino mice (BALB/c) were used in the study and they were grouped as negative-control, PRP treated, BMAC treated and BMAC plus PRP treated. An incisional wound (1 cm2) was made at the back of mouse and their wounds were treated according to their treatment plan and group allocations. Later, the skin at the treated wound sites was collected on days 7, 14, and 21 for histopathological investigation. The results showed that there was a statistically significant difference in BMAC+PRP-treated wounds over the rest of the treated groups in the acceleration of wound healing throughout the experiment by increasing the rate of wound contraction, re-epithelization process, and granulation tissue intensity with fluctuated infiltration in the number of the neutrophils, macrophages, and lymphocytes, also restoration of the epidermal and dermal thickness with less scarring and hair follicle regeneration vs to the negative-control, PRP and BMAC only treated groups. Our findings indicated that BMAC containing mesenchymal stem cells is an efficient approach, which can be used to enhance a smooth and physiopathological healing process, especially when it is used in combination with PRP.

An Update on Orthobiologics: Cautious Optimism

Orthobiologics are rapidly growing in use given their potential to augment healing for multiple musculoskeletal conditions. Orthobiologics consist of a variety of treatments including platelet-rich plasma and stem cells that provide conceptual appeal in providing local delivery of growth factors and inflammation modulation. The lack of standardization in nomenclature and applications within the literature has led to a paucity of high-quality evidence to support their frequent use. The purpose of this review was to describe the current landscape of orthobiologics and the most recent evidence regarding their use.

Autologous bone plug-sliding with core decompression and bone marrow aspirate concentrate application: a joint-preserving surgical technique for corticosteroid-induced osteonecrosis of femoral head

This study aimed to describe a surgical procedure for the management of corticosteroid-induced osteonecrosis of the femoral head (ONFH) and report its clinical results. The technique included harvesting a bone plug from the lateral femoral neck, core decompression, and bone marrow aspirate concentrate (BMAC) application; the procedure was completed by press-fit insertion of the autologous bone plug in the debrided area. Autologous bone plug-sliding with core decompression and bone marrow concentrate aspirate application provides good clinical outcomes in the management of ONFH. A retrospective review was performed using records of patients operated on between October 2019 and June 2021. Only patients with Ficat-Arlet stage-2 ONFH, who underwent the procedure described, were included. Twenty- nine hips (18 patients) were included and evaluated clinically and radiologically. Clinical evaluation included the Harris hip score (HHS) and Visual analogue scale (VAS) for pain, while radiological evaluation included direct radiographs. The average age was 39.8 years (± 11.7, range: 24-65 years). The average follow-up was 13.5 months (± 3.4, range: 8-19 months). There were improvements in the VAS pain and Harris hip scores in all patients. Average HHS increased from 61.90 to 87.45 (p < 0.001), while the average VAS pain score decreased from 7.14 to 3.27 (p < 0.001). No complications were encountered in any of the patients during the follow-up. None of the patients had femoral head collapse on the latest radiograph or required total hip replacement. The combination of the novel autologous bone plug-sliding method with conventional regenerative methods is a successful treatment choice for ONFH.

A Comprehensive Review of Treatment Strategies for Early Avascular Necrosis

Avascular necrosis (AVN), characterised by compromised blood supply leading to bone necrosis, poses a significant challenge in orthopaedic and rheumatologic practice. This review comprehensively examines early AVN treatment strategies, including aetiology and risk factors, clinical presentation, conservative and surgical approaches, emerging therapies, and rehabilitation. Key findings underscore the importance of early detection, personalised treatment plans, and a multidisciplinary approach involving orthopaedic specialists, rheumatologists, and physical therapists. The implications for clinical practice emphasise individualised care, staying abreast of emerging therapies, and patient education. Recommendations for future management strategies highlight the need for imaging technology advancements, regenerative therapies integration, and ongoing research into genetic and molecular pathways. As the field continues to evolve, translating research findings into clinical practice holds promise for improving outcomes and enhancing the overall quality of life for individuals affected by AVN.

Cytokine Dynamics in Autism: Analysis of BMAC Therapy Outcomes

Autism spectrum disorder (ASD) has recently been linked to neuroinflammation and an aberrant immune response within the central nervous system. The intricate relationship between immune response and ASD remains elusive, with a gap in understanding the connection between specific immune mechanisms and neural manifestations in autism. In this study, we employed a comprehensive statistical approach, fusing both overarching and granular methods to examine the concentration of 16 cytokines in the cerebrospinal fluid (CSF) across each autologous bone marrow aspirate concentrate (BMAC) intrathecal administration in 63 male and 17 female autism patients. Following a six-month period post the third administration, patients were stratified into three categories based on clinical improvement: Group 1- no/mild (28 subjects), Group 2-moderate (16 subjects), and Group 3-major improvement (15 subjects). Our integrated analysis revealed pronounced disparities in CSF cytokine patterns and clinical outcomes in autism subjects pre- and post-BMAC transplantation. Crucially, our results suggest that these cytokine profiles hold promise as predictive markers, pinpointing ASD individuals who might not exhibit notable clinical amelioration post-BMAC therapy.

Successful treatment of a benign, non-infected cyst in a dog by bone marrow injections

Bone cysts are rare orthopaedic problems in dogs. There are no clear treatment guidelines. A young male Shih Tzu was referred to Small Animal Clinic with fifth-degree lameness (5/5) of the left thoracic limb, and with swelling and deformation of the distal humeral region. The radiological assessment revealed an enlargement of the distal brachium and an extensive hypodense osteolytic lesion in the distal metaphyseal region of the humerus. Diagnosis of the bone cyst was formulated and treated with a mini-invasive method using autologous non-concentrated bone marrow injections. The treatment was successful, and at the three weeks, the cyst significantly changed its structure. The follow-up at 12 weeks after the first injection, and at one year revealed complete recovery. To our knowledge, this is the first evidence of a bone cyst in a young dog successfully treated with a minimally-invasive method by using a non-concentrated autologous bone marrow injection.

Outcomes and Complications After Bone Marrow Aspirate Harvest From the Calcaneus

Background

Bone marrow aspirate (BMA) is used with the putative goal of enhancing healing of injured tissue. The most common sites to harvest BMA are the iliac crest, the tibia, and the calcaneus. Investigators have found that the tibia and calcaneus have fewer progenitor cells than the iliac crest. This retrospective review evaluates the efficacy and safety profile of harvesting BMA from the calcaneus bone. We hypothesized that harvesting BMA from the calcaneus will have high efficacy and safety profile with low complication rates.

Methods

A retrospective chart review of patients undergoing bone marrow aspiration from the calcaneus bone from January 2019 to October 2022 was performed. The main data points evaluated were patient satisfaction and pain level, follow-up times, quantity of BMA harvested, fusion rates, and complications including nerve damage, infections, and nonunions.

Results

There were 45 (34 female and 11 male) patients who underwent 45 procedures. The average age, BMI, and amount of BMA were 45.1 years (range 23-79), 33.1 (range 19.2-61.3), and 10.3 mL (range 2-40), respectively. There was no pain reported at the final follow-up in 32 patients (71.1%), and there was minimal to no pain in the area of surgery in the remaining 13 patients (28.9%). The 10 cases of fusion successfully healed with combined use of allograft and BMA. The average follow-up time was 12.3 months (range 2.4-33.7). There were no infections, wound complications, or nerve injuries.

Conclusion

Harvesting BMA from the calcaneus bone is a safe procedure. In this heterogenous series where BMA augmented other surgical strategies, patients had little to no pain and there were no cases of wound complication or iatrogenic neuropraxia after undergoing bone marrow harvest from the calcaneus.

Level of Evidence

Level IV, case series.

Clinical Trials with Mesenchymal Stem Cell Therapies for Osteoarthritis: Challenges in the Regeneration of Articular Cartilage

Osteoarthritis (OA) is a whole-joint disease primarily characterized by the deterioration of hyaline cartilage. Current treatments include microfracture and chondrocyte implantation as early surgical strategies that can be combined with scaffolds to repair osteochondral lesions; however, intra-articular (IA) injections or implantations of mesenchymal stem cells (MSCs) are new approaches that have presented encouraging therapeutic results in animal models and humans. We critically reviewed clinical trials with MSC therapies for OA, focusing on their effectiveness, quality, and outcomes in the regeneration of articular cartilage. Several sources of autologous or allogeneic MSCs were used in the clinical trials. Minor adverse events were generally reported, indicating that IA applications of MSCs are potentially safe. The evaluation of articular cartilage regeneration in human clinical trials is challenging, particularly in the inflammatory environment of osteoarthritic joints. Our findings indicate that IA injections of MSCs are efficacious in the treatment of OA and the regeneration of cartilage, but that they may be insufficient for the full repair of articular cartilage defects. The possible interference of clinical and quality variables in the outcomes suggests that robust clinical trials are still necessary for generating reliable evidence with which to support these treatments. We suggest that the administration of just-sufficient doses of viable cells in appropriate regimens is critical to achieve effective and durable effects. In terms of future perspectives, genetic modification, complex products with extracellular vesicles derived from MSCs, cell encapsulation in hydrogels, and 3D bioprinted tissue engineering are promising approaches with which to improve MSC therapies for OA.

Patient Demographic Factors Are Not Associated With Mesenchymal Stromal Cell Concentration in Bone Marrow Aspirate Concentrate

Purpose

To describe the capacity for concentration of a single processing machine for bone marrow aspirate concentrate (BMAC) production and investigate the effects of demographic factors on the number of mesenchymal stromal cells (MSCs) in BMAC.

Methods

Patients enrolled in our institution's randomized control trials involving BMAC who had complete BMAC flow cytometry data were included. Multipotent MSC phenotype, defined as cell-surface coexpression of specific-identifying antigens (≥95% positive) and the absence of hematopoietic lineage markers (≤2% positive), was determined for both patient bone marrow aspirate (BMA) and BMAC samples. The ratio of cells in BMA:BMAC samples was calculated and Spearman correlations (i.e., body mass index [BMI]) and Kruskall-Wallis (i.e., age: <40, 40-60, >60 years) or Mann-Whitney (i.e., sex) tests were used to determine the relationship of cell concentration to demographic factors.

Results

Eighty patients were included in analysis (49% male, mean age: 49.9 ± 12.2 years). Mean concentration of BMA and BMAC was 2,048.13 ± 2,004.14 MSCs/mL and 5,618.87 ± 7,568.54 MSC/mL, respectively, with a mean BMAC:BMA ratio of 4.35 ± 2.09. A significantly greater MSC concentration was observed in the BMAC samples when compared with BMA (P = .005). No patient demographic factors (age, sex, height, weight, BMI) were found to predict MSC concentration in the BMAC samples (P ≥ .01).

Conclusions

Demographic factors, including age, sex, and BMI do not impact the final concentration of MSCs in BMAC when using a single harvest technique (anterior iliac crest) and a single processing system.

Clinical Relevance

As the role of BMAC therapy expands in clinical application, it becomes increasingly important to understand the determinants of BMAC composition and how it is affected by different harvesting techniques, concentrating processes, and patient demographics.

Arthroscopy and Musculoskeletal Biologics

Orthopaedic biologics holds great promise. Absent peer-reviewed clinical musculoskeletal research, orthobiologics indications and treatment recommendations will remain opaque. In a Call for Papers, Arthroscopy; Arthroscopy Techniques; and Arthroscopy, Sports Medicine, and Rehabilitation editors invite authors to submit clinical musculoskeletal biologics original scientific research, and technical notes with video. Each year, the top articles will be awarded inclusion in an annual Biologics Special Issue. Future investigators and current readers could follow the science while being mindful of the regulatory environment.

Orthopaedic Musculoskeletal Biologics Research Impacts Patient Care: The First Annual Arthroscopy Orthobiologics Virtual Special Issue

Orthobiologics can modify symptoms and improve healing in a variety of musculoskeletal conditions as a part of office-based care or as an adjunct to surgery. Orthobiologics harness the benefits of naturally derived blood components, autologous tissue, and growth factors to reduce inflammation and optimize the host-healing environment. The Arthroscopy family of journals seeks to positively influence evidence-based clinical decision-making by publishing peer-reviewed biologics research. This special issue contains recent influential articles strategically chosen to positively impact patient care.

Hydrogel viscoelasticity modulates migration and fusion of mesenchymal stem cell spheroids

Multicellular spheroids made of stem cells can act as building blocks that fuse to capture complex aspects of native in vivo environments, but the effect of hydrogel viscoelasticity on cell migration from spheroids and their fusion remains largely unknown. Here, we investigated the effect of viscoelasticity on migration and fusion behavior of mesenchymal stem cell (MSC) spheroids using hydrogels with a similar elasticity but different stress relaxation profiles. Fast relaxing (FR) matrices were found to be significantly more permissive to cell migration and consequent fusion of MSC spheroids. Mechanistically, inhibition of ROCK and Rac1 pathways prevented cell migration. Moreover, the combination of biophysical and biochemical cues provided by fast relaxing hydrogels and platelet-derived growth factor (PDGF) supplementation, respectively, resulted in a synergistic enhancement of migration and fusion. Overall, these findings emphasize the important role of matrix viscoelasticity in tissue engineering and regenerative medicine strategies based on spheroids.

Bone Marrow Aspirate Concentrate versus Human Umbilical Cord Blood-Derived Mesenchymal Stem Cells for Combined Cartilage Regeneration Procedure in Patients Undergoing High Tibial Osteotomy: A Systematic Review and Meta-Analysis

Background and objectives: Cartilage regeneration using mesenchymal stem cells (MSCs) has been attempted to improve articular cartilage regeneration in varus knee osteoarthritis (OA) patients undergoing high tibial osteotomy (HTO). Bone marrow aspirate concentrate (BMAC) and human umbilical cord blood-derived MSCs (hUCB-MSCs) have been reported to be effective. However, whether BMAC is superior to hUCB-MSCs remains unclear. This systematic review and meta-analysis aimed to determine the clinical efficacy of cartilage repair procedures with BMAC or hUCB-MSCs in patients undergoing HTO. Materials and Methods: A systematic search was conducted using three global databases, PubMed, EMBASE, and the Cochrane Library, for studies in which the clinical outcomes after BMAC or hUCB-MSCs were used in patients undergoing HTO for varus knee OA. Data extraction, quality control, and meta-analysis were performed. To compare the clinical efficacy of BMAC and hUCB-MSCs, reported clinical outcome assessments and second-look arthroscopic findings were analyzed using standardized mean differences (SMDs) with 95% confidence intervals (CIs). Results: The present review included seven studies of 499 patients who received either BMAC (BMAC group, n = 169) or hUCB-MSCs (hUCB-MSC group, n = 330). Improved clinical outcomes were found in both BMAC and hUCB-MSC groups; however, a significant difference was not observed between procedures (International Knee Documentation Committee score; p = 0.91, Western Ontario and McMaster Universities OA Index; p = 0.05, Knee Society Score (KSS) Pain; p = 0.85, KSS Function; p = 0.37). On second-look arthroscopy, the hUCB-MSC group showed better International Cartilage Repair Society Cartilage Repair Assessment grade compared with the BMAC group (p < 0.001). Conclusions: Both BMAC and hUCB-MSCs with HTO improved clinical outcomes in varus knee OA patients, and there was no difference in clinical outcomes between them. However, hUCB-MSCs were more effective in articular cartilage regeneration than BMAC augmentation.

Orthobiologic Use in Sports Injuries

Orthobiologics have gained much popularity in recent years but there has not been a large amount of clinical evidence to support their use. In the limited research that has been published, they have been shown to be effective and safe. They can assist in earlier return to activity with the avoidance of surgery. They can also augment current surgical practice to aid in healing and return to sport with few complications. With new medical innovation, there is unfortunately a higher cost for these products. The use of orthobiologics will only grow and so will the need for high-level clinical evidence.

Management of Massive Mandibular Fibrous Dysplasia with Radical Excision and Different Immediate Reconstructive Modalities: Case Series Report

Purpose

To review and represent three different mandibular reconstruction modalities following surgical treatment of massive mandibular fibrous Dysplasia (MMFD).

Methods

The present retrospective case series study was conducted on 24 patients who had MMFD and treated via resection and immediate reconstruction at Al-Azhar University Hospitals, Egypt. Patients were divided into three groups according to the grafting procedure. Group I patients were grafted with iliac bone graft (IBG), group II patients were grafted with IBG and bone marrow aspirate concentrate (BMAC), while group III patients were grafted with free vascularized fibula graft (FVFG). Postoperative clinical and radiographic assessments were performed immediately, at 6 months, 12 months and 2 years to evaluate lesion recurrence and bone graft resorption. Other study variables included assessment of postoperative wound dehiscence, infection rate, amount of edema, and facial bone contour.

Results

The parameters of the clinical analysis showed non-statistically significant differences among all groups. Postoperative wound healing was clinically uneventful in all groups, except for two cases of wound dehiscence in group I (8.3%) and one case in group III (4.2%). Most patients had appropriate postoperative facial contour, and adequate facial symmetry. The radiographic measurements revealed a highly statistically significant difference between group I and II at 12 months, and two years, without any statistically significant difference between group II and III.

Conclusion

MMFD surgical defect should be repaired for function and cosmetics aims especially in young adult patients. The findings of the present study have shown that when compared to traditional IBG alone or FVFG, the use of autogenous IBG with BMAC injection produces a favorable outcome with few difficulties.

Hamstring Injuries: Critical Analysis Review of Current Nonoperative Treatments

➢

Hamstring injuries are common among active and athletic individuals, especially those involved in high-speed running, distance running, or sports requiring sudden directional changes. Acute hamstring strains often occur as an eccentric strain during running or a stretch-type injury caused by simultaneous hip flexion and knee extension. Proximal hamstring tendinopathy is an overuse injury of the hamstring tendon as a result of chronic cicatrization of the musculotendinous unit.

➢

Repeated stress to the hamstring tendon leads to increased cellularity of tendon fibers, disruption of collagen, and subsequent microinjury of the tissue that attaches the tendon to bone.

➢

Management of hamstring injuries generally begins with nonoperative modalities consisting of eccentric rehabilitative exercise programs. Although various other treatment modalities are available, the comparative efficacy of these supportive measures is not well differentiated at this time.

➢

In this article, we review the current literature with regard to the nonoperative treatment of hamstring injuries, specifically focusing on acute hamstring muscle strains and proximal hamstring tendinopathy in order to provide supplementary insight on the effectiveness of current modalities.

The Analgesic Efficacy of Intradiscal Injection of Bone Marrow Aspirate Concentrate and Culture-Expanded Bone Marrow Mesenchymal Stromal Cells in Discogenic Pain: A Systematic Review

Pain originating from the intervertebral disc (discogenic pain) is a prevalent manifestation of low back pain and is often challenging to treat. Of recent interest, regenerative medicine options with injectable biologics have been trialed in discogenic pain and a wide variety of other painful musculoskeletal conditions. In particular, the role of bone marrow aspirate concentrate (BMAC) and culture-expanded bone marrow derived mesenchymal stromal cells (BM-MSCs) in treating discogenic pain remains unclear. The primary objective of this systematic review was to appraise the evidence of intradiscal injection with BMAC and culture-expanded BM-MSCs in alleviating pain intensity from discogenic pain. Secondary outcomes included changes in physical function after intradiscal injection, correlation between stromal cell count and pain intensity, and anatomical changes of the disc assessed by radiographic imaging after intradiscal injection. Overall, 16 studies consisting of 607 participants were included in qualitative synthesis without pooling. Our synthesis revealed that generally intradiscal autologous or allogeneic BMAC and culture-expanded BM-MSCs improved discogenic pain compared to baseline. Intradiscal injection was also associated with improvements in physical functioning and positive anatomical changes on spine magnetic resonance imaging (improved disc height, disc water content, Pfirrmann grading) although anatomical findings were inconsistent across studies. However, the overall GRADEscore for this study was very low due to heterogeneity and poor generalizability. There were no serious adverse events reported post intradiscal injection except for a case of discitis.

Effectiveness of Bone Marrow-Derived Platelet-Rich Fibrin on Rotator Cuff Healing in a Rabbit Degenerative Model

BACKGROUND

Platelet-rich fibrin (PRF) is a second-generation platelet concentrate. Although peripheral blood-derived PRF (P-PRF) is commonly applied in biological augmentation, there is no report about the therapeutic effect of bone marrow-derived PRF (BM-PRF) for degenerative rotator cuff tears (RCTs).

PURPOSE/HYPOTHESIS

To examine the effects of platelet-rich plasma (PRP), P-PRF, and BM-PRF during rotator cuff repair (RCR) in degenerative RCTs in rabbits. We hypothesized that BM-PRF would accelerate the bone-tendon healing after RCR.

STUDY DESIGN

Controlled laboratory study.

METHODS

Degenerative RCT models were created 2 weeks before beginning the study, and 68 juvenile rabbits were divided into 4 groups: the control, PRP, P-PRF, and BM-PRF groups. RCR without augmentation was done in the control group. PRP was prepared by centrifuging peripheral blood twice using a plastic tube. P-PRF and BM-PRF were prepared by centrifuging peripheral blood and bone marrow, respectively, using a glass tube. Rabbits from PRP, P-PRF, and BM-PRF groups were administered the augmentation in a similar fashion for RCR, between the rotator cuff and the footprint of the humerus. At 4, 8, and 12 weeks, rabbits were euthanized and histologically assessed using hematoxylin and eosin staining, Alcian blue staining, and immunohistochemical staining for type I and III collagen. The sections were also evaluated with immunofluorescence staining of vascular endothelial growth factor (VEGF) at 4 weeks.

RESULTS

The continuity was significantly better in the BM-PRF group at 4 weeks (P < .05). Immunofluorescence staining demonstrated that VEGF-positive stained cells were significantly greater in the BM-PRF group than in the control group (P < .01). The modified tendon maturing score was significantly greater in the BM-PRF group than in the control and PRP groups at 12 weeks (P < .05). There was no significant difference in the modified tendon maturing score of the P-PRF group compared with the control group.

CONCLUSION

The rabbit model of degenerative RCTs demonstrated that RCR combined with BM-PRF enhanced tendon-bone continuity and increased the VEGF-positive cells at 4 weeks and obtained preferable tendon-bone maturation at 12 weeks.

CLINICAL RELEVANCE

RCR augmented with BM-PRF has the potential to improve clinical outcomes for RCTs.

Bone marrow aspirate concentrate quality is affected by age and harvest site

PURPOSE

To compare the number and properties of bone marrow stromal cells (BMSCs) collected from bone marrow aspirate concentrate (BMAC) obtained from different harvest sites and from patients of different ages.

METHODS

BMAC was obtained from two groups of patients based on age (n = 10 per group): 19.0 ± 2.7 years for the younger and 56.8 ± 12.5 for the older group. In the latter, BMAC was obtained from both iliac crest and proximal tibia for a donor-matched analysis. Mononucleated cell count and CFU-F assay were performed, together with phenotype characterization of BMSCs from iliac crest and proximal tibia, the study of chondrogenic and osteogenic differentiation capacity, histological staining and spectrophotometric quantification, and the analysis of mRNAs expression.

RESULTS

Cells derived from iliac crest and proximal tibia showed the same phenotypic pattern at flow cytometry, as well as similar chondrogenic and osteogenic potential. However, a significantly higher number of mononuclear cells per ml was observed in younger patients (3.8 ± 1.8 × 10⁷) compared to older patients (1.2 ± 0.8 × 10⁷) (p < 0.0005). The latter yield, obtained from the iliac crest, was significantly higher than resulting from the BMAC harvested from the proximal tibia in the same group of patients (0.3 ± 0.2 × 10⁷, p < 0.0005). This result was confirmed by the CFU-F analysis at day 10 (15.9 ± 19.4 vs 0.6 ± 1.0, p = 0.001) and day-20 (21.7 ± 23.0 vs 2.9 ± 4.2, p = 0.006).

CONCLUSION

Harvest site and age can affect the quality of BMAC. BMSCs obtained from iliac crest and proximal tibia present comparable mesenchymal markers expression as well as osteogenic and chondrogenic differentiation potential, but iliac crest BMAC presents a four times higher number of mononucleated cells with significantly higher clonogenic capacity compared to the tibia. BMAC of younger patients also had a three-time higher number of mononucleated cells. The identification of BMAC characteristics could help to optimize its preparation and to identify the most suitable indications for this orthobiologic treatment in the clinical practice.

Mesenchymal stem cells augmentation for surgical procedures in patients with symptomatic chondral defects of the knee: a systematic review

Background

The efficacy and safety profile of mesenchymal stem cells (MSCs) augmentation in chondral procedures are controversial. This systematic review updated the current evidence on MSCs augmentation for chondral procedures in patients with symptomatic chondral defects of the knee.

Methods

This study followed the PRISMA guidelines. The literature search was updated in August 2022. Two independent authors accessed PubMed, Google scholar, Embase, and Scopus. No additional filters or time constrains were used for the search. A cross reference of the bibliographies was also performed. All the clinical studies investigating surgical procedures for chondral defects of the knee augmented with MSCs were accessed. Defects of both tibiofemoral and patellofemoral joints were included. The following patient reported outcomes measures (PROMs) were retrieved at baseline and last follow-up: Visual Analogic Scale (VAS), Tegner Activity Scale, Lysholm Knee Scoring System, International Knee Documentation Committee (IKDC). Return to daily activities and data on hypertrophy, failure, revision surgery were also collected. Failures were defined as the recurrence of symptoms attributable to the index procedure. Revisions were defined as any reoperation at the site of the index procedure.

Results

A total of 15 clinical studies (411 procedures) were included. Patients returned to their prior sport activity at 2.8 ± 0.4 months. All the PROMs improved at last follow-up: Tegner (P = 0.0002), Lysholm (P < 0.0001), the IKDC (P < 0.0001), VAS (P < 0.0001). At a mean of 30.1 ± 13.9 months, 3.1% (2 of 65 patients) reported graft hypertrophy, 3.2% (2 of 63) were considered failures. No surgical revision procedures were reported. Given the lack of available quantitative data for inclusion, a formal comparison of surgical procedures was not conducted.

Conclusion

MSCs augmentation in selected chondral procedures could be effective, with a low rate of complications. Further investigations are required to overcome the current limitations to allow the clinical translation of MSCs in regenerative medicine.

Reorientation technique has benefits in bone marrow aspiration of stem cells

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

Level of Evidence: Level I.

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

Bone Marrow Aspirate Concentrate Augmentation May Accelerate Allograft Ligamentization in Anterior Cruciate Ligament Reconstruction: A Double-Blinded Randomized Controlled Trial

PURPOSE

To assess the effect of bone marrow aspiration concentrate (BMAC) augmentation on clinical outcomes and magnetic resonance imaging (MRI) findings in anterior cruciate ligament (ACL) reconstruction (ACLR) with bone-patellar tendon-bone (BTB) allografts.

METHODS

A double-blinded, randomized controlled trial was conducted on 80 patients undergoing ACL reconstruction using BTB allografts. Patients were randomized to 2 groups: (1) bone marrow aspirate was collected from the iliac crest, concentrated, and approximately 2.5 mL was injected into the BTB allograft, or (2) a small sham incision was made at the iliac crest (control). MRI was performed at 3 months and 9 months postoperatively to determine the signal intensity ratio of the ACL graft.

RESULTS

Seventy-three patients were available for follow-up at 1-year postoperatively (36 BMAC, 37 control). International Knee Documentation Committee (IKDC) scores were significantly greater in the BMAC group versus the control at the 9-month postoperative period (81.6 ± 10.5 vs 74.6 ± 14.2, P = .048). There was no significant difference in the proportion of patients who met the minimal clinically important difference for IKDC between the BMAC and control groups at 9 months (89% vs 85%; P = .7). Three months postoperatively, signal intensity ratio of the inferior third of the ACL graft was significantly greater in the BMAC group versus the control group (3.2 ± 2.2 vs 2.1 ± 1.5; P = .02).

CONCLUSIONS

Patients who received BMAC augmentation of the BTB allograft during ACL reconstruction demonstrated greater signal intensity scores on MRI at 3 months, suggesting increased metabolic activity and remodeling, and potentially accelerated ligamentization. Additionally, patients in the BMAC group had greater patient-reported outcomes (IKDC) at 9 months postoperatively when compared with those who underwent a standard surgical procedure. There was no significant difference in the proportion of patients who met the minimal clinically important difference for IKDC between the BMAC and control groups at 9 months, suggesting limited clinical significance at this time point.

LEVEL OF EVIDENCE

I, randomized control trial.

State of the field: cellular and exosomal therapeutic approaches in vascular regeneration

Pathologies of the vasculature including the microvasculature are often complex in nature, leading to loss of physiological homeostatic regulation of patency and adequate perfusion to match tissue metabolic demands. Microvascular dysfunction is a key underlying element in the majority of pathologies of failing organs and tissues. Contributing pathological factors to this dysfunction include oxidative stress, mitochondrial dysfunction, endoplasmic reticular (ER) stress, endothelial dysfunction, loss of angiogenic potential and vascular density, and greater senescence and apoptosis. In many clinical settings, current pharmacologic strategies use a single or narrow targeted approach to address symptoms of pathology rather than a comprehensive and multifaceted approach to address their root cause. To address this, efforts have been heavily focused on cellular therapies and cell-free therapies (e.g., exosomes) that can tackle the multifaceted etiology of vascular and microvascular dysfunction. In this review, we discuss 1) the state of the field in terms of common therapeutic cell population isolation techniques, their unique characteristics, and their advantages and disadvantages, 2) common molecular mechanisms of cell therapies to restore vascularization and/or vascular function, 3) arguments for and against allogeneic versus autologous applications of cell therapies, 4) emerging strategies to optimize and enhance cell therapies through priming and preconditioning, and, finally, 5) emerging strategies to bolster therapeutic effect. Relevant and recent clinical and animal studies using cellular therapies to restore vascular function or pathologic tissue health by way of improved vascularization are highlighted throughout these sections.

Advancing Regenerative Cellular Therapies in Non-Scarring Alopecia

Alopecia or baldness is a common diagnosis in clinical practice. Alopecia can be scarring or non-scarring, diffuse or patchy. The most prevalent type of alopecia is non-scarring alopecia, with the majority of cases being androgenetic alopecia (AGA) or alopecia areata (AA). AGA is traditionally treated with minoxidil and finasteride, while AA is treated with immune modulators; however, both treatments have significant downsides. These drawbacks compel us to explore regenerative therapies that are relatively devoid of adverse effects. A thorough literature review was conducted to explore the existing proven and experimental regenerative treatment modalities in non-scarring alopecia. Multiple treatment options compelled us to classify them into growth factor-rich and stem cell-rich. The growth factor-rich group included platelet-rich plasma, stem cell-conditioned medium, exosomes and placental extract whereas adult stem cells (adipose-derived stem cell-nano fat and stromal vascular fraction; bone marrow stem cell and hair follicle stem cells) and perinatal stem cells (umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs), Wharton jelly-derived MSCs (WJ-MSCs), amniotic fluid-derived MSCs (AF-MSCs), and placental MSCs) were grouped into the stem cell-rich group. Because of its regenerative and proliferative capabilities, MSC lies at the heart of regenerative cellular treatment for hair restoration. A literature review revealed that both adult and perinatal MSCs are successful as a mesotherapy for hair regrowth. However, there is a lack of standardization in terms of preparation, dose, and route of administration. To better understand the source and mode of action of regenerative cellular therapies in hair restoration, we have proposed the "À La Mode Classification". In addition, available evidence-based cellular treatments for hair regrowth have been thoroughly described.

Bioengineered Living Bone Grafts-A Concise Review on Bioreactors and Production Techniques In Vitro

It has been observed that bone fractures carry a risk of high mortality and morbidity. The deployment of a proper bone healing method is essential to achieve the desired success. Over the years, bone tissue engineering (BTE) has appeared to be a very promising approach aimed at restoring bone defects. The main role of the BTE is to apply new, efficient, and functional bone regeneration therapy via a combination of bone scaffolds with cells and/or healing promotive factors (e.g., growth factors and bioactive agents). The modern approach involves also the production of living bone grafts in vitro by long-term culture of cell-seeded biomaterials, often with the use of bioreactors. This review presents the most recent findings concerning biomaterials, cells, and techniques used for the production of living bone grafts under in vitro conditions. Particular attention has been given to features of known bioreactor systems currently used in BTE: perfusion bioreactors, rotating bioreactors, and spinner flask bioreactors. Although bioreactor systems are still characterized by some limitations, they are excellent platforms to form bioengineered living bone grafts in vitro for bone fracture regeneration. Moreover, the review article also describes the types of biomaterials and sources of cells that can be used in BTE as well as the role of three-dimensional bioprinting and pulsed electromagnetic fields in both bone healing and BTE.

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

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

Clinical and functional evaluation of bone marrow aspirate concentrate vs autologous conditioned serum in the treatment of knee osteoarthritis

BACKGROUND AND AIM

The aim of this study was to compare the efficacy of a single Bone Marrow Aspirate Concentrate (BMAC) with a cycle of 4 Autologous Conditioned Serum (ACS) injections in the treatment of early-stage knee osteoarthritis (OA).

METHODS

Two groups of 12 patients with degenerative knee OA were treated with a single BMAC injection and with a cycle of 4 ACS injections respectively. Follow-up was set at baseline (t0), one-month (t1) and six-months (t2) evaluating VAS for pain, WOMAC index and range of motion (ROM).

RESULTS

We reported a significant improvement in WOMAC after BMAC injection both at t1 (p= 0,001) as well as t2 (p< 0,001), plus a reduction of VAS values in BMAC group at six months follow-up (p = 0,024). In contrast, no significant differences in ROM between the two groups were observed.

CONCLUSIONS

Both the approaches are safe and effective in the treatment of knee OA, with a major efficacy of BMAC.

High Variability of Mesenchymal Stem Cells Obtained via Bone Marrow Aspirate Concentrate Compared With Traditional Bone Marrow Aspiration Technique

Background:

Bone marrow aspirate (BMA) is a common source for harvesting mesenchymal stem cells (MSCs), other progenitor cells, and associated cytokines and growth factors to be used in the biologic treatment of various orthopaedic pathologies. The aspirate is commonly centrifuged into a concentrated volume that can be immediately administered to a patient using commercially available kits. However, the handling and efficacy of BMA concentrate (BMAC) are still controversial.

Purpose:

To characterize BMA versus BMAC for MSC quantity, potency, and cytokine profile.

Study Design:

Controlled laboratory study.

Methods:

From 8 participants (age, 17-68 years), 30 mL of bone marrow was aspirated by a single surgeon from either the proximal humerus or distal femur and was separated into 2 equal samples. One sample was kept as BMA, and the other half was centrifuged into BMAC. The 2 samples then underwent flow cytometry for detection of MSCs, cell analysis for colony-forming units (CFUs), and cytokine profiling. A 2-tailed t test was used to detect differences between MSCs, CFUs, and cytokine density concentrations between BMA and BMAC.

Results:

The average concentration of MSCs in both BMA and BMAC was 0.001%. Average MSC events detected by flow cytometry were significantly higher in BMA versus BMAC (15.1 and 8.1, respectively; P < .045). Expanded MSCs demonstrated similar phenotypes, but CFUs were significantly increased in BMA compared with BMAC (104 vs 68 CFUs, respectively; P < .001). Total protein concentration and cytokine profiling demonstrated great variability between BMA and BMAC and between patients. Most importantly, BMAC failed to concentrate MSCs in 6 of 8 samples.

Conclusion:

There is great variability in MSC concentration, total protein concentration, and cytokine profile between BMA and BMAC.

Clinical Relevance:

When studying the clinical efficacy of BMAC, one must also evaluate the sample itself to determine the presence, concentration, and potency of MSCs if this is to be considered a cell-based therapy. Further standard operating procedures need to be investigated to ensure reproducible results and appropriate treatments.

Combined Bone Marrow Aspirate and Platelet-Rich Plasma for Cartilage Repair: Two-Year Clinical Results

PURPOSE

To evaluate the clinical and biological outcome of combined bone marrow aspirate concentrate (BMAC) and platelet-rich plasma (PRP) on a collagen scaffold for treating cartilage lesions in the knee.

METHODS AND MATERIALS

Ten patients (mean age 29.4 years, range 18-36) suffering from large full-thickness cartilage in the knee were treated with BMAC and PRP from January 2015 to December 2016. In a 1-step procedure autologous BMAC and PRP was seeded onto a collagen scaffold and sutured into the debrided defect. Patients were evaluated by clinical outcome scores (IKDC [International Knee Documentation Committee Subjective Knee Form], KOOS [Knee Injury and Osteoarthritis Outcome Score], and pain score using the Numeric Rating Scale [NRS]) preoperatively, after 3 months, and after 1 and 2 years. Second-look arthroscopies were performed (n = 7) with biopsies of the repair tissue for histology. All patients had magnetic resonance imaging (MRI) preoperatively, after 1 year, and after 2 to 3.5 years with MOCART (magnetic resonance observation of cartilage repair tissue) scores evaluating cartilage repair.

RESULTS

After 1 year significant improvements were found in IKDC, KOOS symptoms, KOOS ADL (Activities of Daily Living), KOOS QOL (Quality of Life), and pain at activity. At the latest follow-up significant improvements were seen in IKDC, KOOS symptoms, KOOS QOL, pain at rest, and pain at activity. MRI MOCART score for cartilage repair improved significantly from baseline to 1-year follow-up. Histomorphometry of repair tissue demonstrated a mixture of fibrous tissue (58%) and fibrocartilage (40%).

CONCLUSION

Treatment of cartilage injuries using combined BMAC and PRP improved subjective clinical outcome scores and pain scores at 1 and 2 years postoperatively. MRI and histology indicated repair tissue inferior to the native hyaline cartilage.