Autologous Chondrocyte Implantation and Mesenchymal Stem Cells for the Treatments of Chondral Defects of the Knee- A Systematic Review

Treatment of knee cartilage by cultured stem cells and three dimensional scaffold: a phase I/IIa clinical trial

PURPOSE

Damage of the knee cartilage is a common condition manifesting itself mainly by pain and/or swelling that may substantially reduce the quality of life while ultimately leading to osteoarthritis in affected patients. Here, we aimed to evaluate the safety and efficacy of cultured autologous bone marrow mesenchymal stem cells (BM-MSCs) attached to the 3D Chondrotissue® scaffold by autologous blood plasma coagulation (BiCure® ortho MSCp) in the treatment of knee cartilage defects.

METHODS

The primary endpoint of this phase I/IIa clinical trial was to evaluate the safety of the treatment. The secondary objective was to determine the short-to-medium-term therapeutic outcomes by standardized scoring questionnaires including Lysholm Knee Scoring Scale (Lysholm score), Knee Injury and Osteoarthritis Outcome Score (KOOS), and pain Visual Analogue Scale (VAS) systems and imaging (X-ray and magnetic resonance imaging, MRI). A total of six patients were included and followed for 12 months after the surgery.

RESULTS

BiCure® ortho MSCp was well tolerated with no adverse events associated with the investigational medicinal product. Significant improvements were observed in Lysholm scores and KOOS while X-ray showed no deterioration of the arthritis and MRI revealed a persistent filling of the chondral defects by the implant.

CONCLUSION

Overall, our data demonstrate the safety of the tested investigational medicinal product. The function of the treated knee improved within one year after surgery in all enrolled patients.

TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION

EudraCT No.: 2018-004,067-31; October 18 2018.

Bone Marrow-Derived Mesenchymal Stem Cell Implants for the Treatment of Focal Chondral Defects of the Knee in Animal Models: A Systematic Review and Meta-Analysis

Osteoarthritis remains an unfortunate long-term consequence of focal cartilage defects of the knee. Associated with functional loss and pain, it has necessitated the exploration of new therapies to regenerate cartilage before significant deterioration and subsequent joint replacement take place. Recent studies have investigated a multitude of mesenchymal stem cell (MSC) sources and polymer scaffold compositions. It is uncertain how different combinations affect the extent of integration of native and implant cartilage and the quality of new cartilage formed. Implants seeded with bone marrow-derived MSCs (BMSCs) have demonstrated promising results in restoring these defects, largely through in vitro and animal studies. A PRISMA systematic review and meta-analysis was conducted using five databases (PubMed, MEDLINE, EMBASE, Web of Science, and CINAHL) to identify studies using BMSC-seeded implants in animal models of focal cartilage defects of the knee. Quantitative results from the histological assessment of integration quality were extracted. Repair cartilage morphology and staining characteristics were also recorded. Meta-analysis demonstrated that high-quality integration was achieved, exceeding that of cell-free comparators and control groups. This was associated with repair tissue morphology and staining properties which resembled those of native cartilage. Subgroup analysis showed better integration outcomes for studies using poly-glycolic acid-based scaffolds. In conclusion, BMSC-seeded implants represent promising strategies for the advancement of focal cartilage defect repair. While a greater number of studies treating human patients is necessary to realize the full clinical potential of BMSC therapy, high-quality integration scores suggest that these implants could generate repair cartilage of substantial longevity.

Fibrin glue does not promote migration and proliferation of bone marrow derived mesenchymal stem cells in collagenic membranes: an in vitro study

During Autologous Matrix-Induced Chondrogenesis (AMIC), the membrane is often glued into the chondral defect. However, whether fibrin glue influences cells proliferation and migration remain unclear. This study evaluated the impact of fibrin glue addition to biologic membranes loaded with bone marrow-derived mesenchymal stem cells (B-MSCs). A porcine derived collagen membrane (Cartimaix, Matricel GmbH, Germany) was used. B-MSCs were harvested from three different unrelated donors. The membranes were embedded in mounting medium with DAPI (ABCAM, Cambridge, UK) and analysed at 1-, 2-, 3-, 4-, 6-, and at 8-week follow-up. The DAPI ties the DNA of the cell nucleus, emitting blue fluorescence. DAPI/nuclei signals were analysed with fluorescence microscopy at 100-fold magnification. The group without fibrin glue demonstrated greater migration of the B-MSCs within the membrane at week 4 (P < 0.001), 6 (P < 0.001), and 8 (P < 0.001). No difference was found at week 1, 2, and 3. The group without fibrin glue demonstrated greater proliferation of B-MSCs within the membrane. These differences were significant at week 1 (P = 0.02), 2 (P = 0.008), 3 (P = 0.0009), 4 (P < 0.0001), 6 (P < 0.0001), 8 (P < 0.0001). Concluding, in the present setting, the use of fibrin in a collagenic biomembrane impairs B-MSCs proliferation and migration in vitro.

Autologous chondrocyte implantation in the knee is effective in skeletally immature patients: a systematic review

PURPOSE

This systematic review evaluated the efficacy and safety of autologous chondrocyte implantation (ACI) for chondral defects of the knee in skeletally immature patients. Current available data from patients reported outcome measures (PROMs) and complications were collected, analyzed, and discussed.

METHODS

This systematic review was conducted according to the PRISMA guidelines. The following databases were accessed in May 2022: PubMed, Google scholar, Embase, and Scopus. All the clinical studies investigating the efficacy of ACI to manage chondral defects of the knee in skeletally immature patients were accessed. Articles treating patients with surgical procedures other than ACI were not eligible, nor were studies with a follow-up shorter than 12 months.

RESULTS

Data from 9 studies (251 procedures) were collected. 32% (80 of 251) of patients were females. The mean length of follow-up was 44.2 ± 29.4 (range, 12-115) months. The mean age of the patients was 16.4 ± 0.7 (range, 15-17) years. The Knee injury and Osteoarthritis Outcome Score (KOOS) and International Knee Document Committee (IKDC) increased of + 41.9/100 (P = 0.003) and + 33.2/100 (P =  < 0.0001) points, respectively. The Lysholm Knee Score improved of + 20.6/100 (P = 0.02) points. The Visual Analogue Scale (VAS) for pain reduced of - 3.6/10 (P = 0.004) points. The Tegner scale did not show any statistically significant improvement from baseline to follow-up (P = n.s.). The rate of graft hypertrophy was 12.5% (5 of 40 patients), and the rate of failure 5.6% (8 of 142 patients).

CONCLUSION

ACI for chondral defects of the knee is effective to improve PROMs in skeletally immature patients. The safety profile of ACI still remains controversial.

LEVEL OF EVIDENCE

III.

Autologous Matrix-Induced Chondrogenesis (AMIC) for Osteochondral Defects of the Talus: A Systematic Review

Autologous matrix-induced chondrogenesis (AMIC) has been advocated for the management of talar osteochondral lesions (OCLs). This systematic review, which was conducted according to the PRISMA 2020 guidelines, investigated the clinical and imaging efficacy and safety of the AMIC technique in the management of OCLs of the talus. Only studies investigating AMIC for talar chondral defects that were published in peer-reviewed journals were considered. In September 2022, the following databases were accessed: PubMed, Web of Science, Google Scholar, and Embase. Data on the visual analogue scale (VAS), American Orthopaedic Foot and Ankle Score (AOFAS), Tegner activity scale, and Foot Function Index (FFI) were retrieved. To evaluate the morphological MRI findings, data obtained from the magnetic resonance observation of cartilage repair tissue (MOCART) scores were evaluated. Data on hypertrophy, failures, and revision surgeries were also collected. Data from 778 patients (39% women, 61% men) were collected. The mean length of the follow-up was 37.4 ± 16.1 months. The mean age of the patients was 36.4 ± 5.1 years, and the mean BMI was 26.1 ± 1.6 kg/m2. The mean defect size was 2.1 ± 1.9 cm2. Following the AMIC technique, patients demonstrated an improved VAS (p < 0.001), AOFAS (p < 0.001), and FFI (p = 0.02) score. The MOCART score also improved from the baseline (p = 0.03). No difference was observed in the Tegner score (p = 0.08). No graft delamination and hypertrophy were reported in 353 patients. 7.8% (44 of 564) of patients required revision surgeries, and 6.2% (32 of 515) of patients were considered failures. The AMIC technique could be effective in improving symptoms and the function of chondral defects of the talus.

Fixation of the Membrane during Matrix-Induced Autologous Chondrocyte Implantation in the Knee: A Systematic Review

Introduction: It is unclear whether the type of membrane used for matrix-assisted autologous chondrocyte implantation (mACI) influences results. A systematic review was conducted to investigate the midterm results of the three most common types of membrane fixation for mACI. Methods: This systematic review was conducted according to the 2020 PRISMA checklist. PubMed, Google Scholar, Embase, and Scopus online databases were accessed in August 2022. All the prospective clinical trials reporting outcomes of mACI in the knee were considered. Studies that describe the modality of membrane fixation (glued, glued, and sutured, no fixation) used for mACI were eligible. Studies that conducted a minimum of 12 months of follow-up were considered. The outcomes of interest were the Tegner Activity Scale and International Knee Documentation Committee (IKDC) score. The rate of failure and revisions were also collected. Results: Data from 26 studies (1539 procedures; 554 of 1539 (36%) were women) were retrieved. The mean follow-up was 42.6 (12 to 84) months. No difference between the groups was found in terms of mean duration of symptoms, age, BMI, gender, and defect size (P > 0.1). No difference was found in terms of the Tegner score (P = 0.3). When no fixation was used, a statistically significant higher IKDC compared to the other groups (P = 0.02) was evidenced. No difference was found in the rate of failure (P = 0.1). The no-fixation group evidenced a statistically significant lower rate of revisions (P = 0.02). Conclusions: No membrane fixation for mACI in the knee scored better than the fastening techniques at the midterm follow-up.

Allograft Versus Autograft Osteochondral Transplant for Chondral Defects of the Talus: Systematic Review and Meta-analysis

BACKGROUND

It is unclear whether the results of osteochondral transplant using autografts or allografts for talar osteochondral defect are equivalent.

PURPOSE

A systematic review of the literature was conducted to compare allografts and autografts in terms of patient-reported outcome measures (PROMs), MRI findings, and complications.

STUDY DESIGN

Systematic review; Level of evidence, 4.

METHODS

This study was conducted according to the PRISMA guidelines. The literature search was conducted in February 2021. All studies investigating the outcomes of allograft and/or autograft osteochondral transplant as management for osteochondral defects of the talus were accessed. The outcomes of interest were visual analog scale (VAS) score for pain, American Orthopaedic Foot and Ankle Society (AOFAS) score, and Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score. Data concerning the rates of failure and revision surgery were also collected. Continuous data were analyzed using the mean difference (MD), whereas binary data were evaluated with the odds ratio (OR) effect measure.

RESULTS

Data from 40 studies (1174 procedures) with a mean follow-up of 46.5 ± 25 months were retrieved. There was comparability concerning the length of follow-up, male to female ratio, mean age, body mass index, defect size, VAS score, and AOFAS score (P > .1) between the groups at baseline. At the last follow-up, the MOCART (MD, 10.5; P = .04) and AOFAS (MD, 4.8; P = .04) scores were better in the autograft group. The VAS score was similar between the 2 groups (P = .4). At the last follow-up, autografts demonstrated lower rate of revision surgery (OR, 7.2; P < .0001) and failure (OR, 5.1; P < .0001).

CONCLUSION

Based on the main findings of the present systematic review, talar osteochondral transplant using allografts was associated with higher rates of failure and revision compared with autografts at midterm follow-up.

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.

Osteoarthritis Risks and Sports: An Evidence-based Systematic Review

PURPOSE

Regular sports activities are associated with multiple physical and psychological health benefits. However, sports also may lead to injuries and the development of osteoarthritis (OA). This systematic review investigated the association between sports activity, sports type, and the risk of developing OA.

METHODS

A systematic review was performed by assessing studies that have investigated the risk of OA development in sports. Data extracted included general information, study design, number of participants, related body mass index, sports type, and assessment of OA. The methodological quality of the studies was assessed using the Newcastle-Ottawa Scale.

RESULTS

A total of 63 studies were included in this systematic review. The overall Newcastle-Ottawa Scale score was 6.46±1.44 demonstrating a good methodological quality of the articles included in the present study. A total of 628,036 participants were included, with a mean follow-up of 8.0±8.4 years. The mean age of the included athletes was 45.6±15.8, with a mean body mass index of 24.9±2.3 kg/m 2 .

CONCLUSION

Football and soccer players seem to be at higher risk for the development of OA, although the injury status of the joint should be considered when assessing the risk of OA. High equipment weight and increased injury risk also put military personnel at a higher risk of OA, although elite dancing leads to more hip labral tears. Femoroacetabular impingement was also often diagnosed in ice-hockey players and ballet dancers.

Functionalized Electrospun Scaffold-Human-Muscle-Derived Stem Cell Construct Promotes In Vivo Neocartilage Formation

Polycaprolactone (PCL) is a non-cytotoxic, completely biodegradable biomaterial, ideal for cartilage tissue engineering. Despite drawbacks such as low hydrophilicity and lack of functional groups necessary for incorporating growth factors, it provides a proper environment for different cells, including stem cells. In our study, we aimed to improve properties of scaffolds for better cell adherence and cartilage regeneration. Thus, electrospun PCL–scaffolds were functionalized with ozone and loaded with TGF-β3. Together, human-muscle-derived stem cells (hMDSCs) were isolated and assessed for their phenotype and potential to differentiate into specific lineages. Then, hMDSCs were seeded on ozonated (O) and non-ozonated (“naïve” (NO)) scaffolds with or without protein and submitted for in vitro and in vivo experiments. In vitro studies showed that hMDSC and control cells (human chondrocyte) could be tracked for at least 14 days. We observed better proliferation of hMDSCs in O scaffolds compared to NO scaffolds from day 7 to day 28. Protein analysis revealed slightly higher expression of type II collagen (Coll2) on O scaffolds compared to NO on days 21 and 28. We detected more pronounced formation of glycosaminoglycans in the O scaffolds containing TGF-β3 and hMDSC compared to NO and scaffolds without TGF-β3 in in vivo animal experiments. Coll2-positive extracellular matrix was observed within O and NO scaffolds containing TGF-β3 and hMDSC for up to 8 weeks after implantation. These findings suggest that ozone-treated, TGF-β3-loaded scaffold with hMDSC is a promising tool in neocartilage formation.

Cell therapies for chondral defects of the talus: a systematic review

Background

This systematic review investigated the efficacy and safety of surgical procedures augmented with cell therapies for chondral defects of the talus.

Methods

The present systematic review was conducted according to the 2020 PRISMA guidelines. PubMed, Google scholar, Embase, and Scopus databases were accessed in March 2022. All the clinical trials investigating surgical procedures for talar chondral defects augmented with cell therapies were accessed. The outcomes of interest were to investigate whether surgical procedures augmented with cell therapies promoted improvement in patients reported outcomes measures (PROMs) with a tolerable rate of complications.

Results

Data from 477 procedures were retrieved. At a mean follow-up of 34.8 ± 9.7 months, the Visual Analogic Scale (VAS) improved of 4.4/10 (P = 0.002) and the American Orthopaedic Foot and Ankle Score (AOFAS) of 31.1/100 (P = 0.0001) points. No improvement was found in Tegner score (P = 0.4). Few articles reported data on complications. At last follow-up, the rate of reoperation and failure were 0.06% and 0.03%, respectively. No graft delamination or hypertrophy was observed.

Conclusion

The current evidence suggests that cell therapies may be effective and safe to enhance surgical procedures for chondral defects of the talus. These results should be considered within the limitations of the present study. The current literature should be enriched with randomized controlled clinical trials with larger population size and longer follow-up.

Fibrin glue does not assist migration and proliferation of chondrocytes in collagenic membranes: an in vitro study

BACKGROUND

Some authors secured the membrane during matrix-induced autologous chondrocyte implantation (mACI) with fibrin glue or did not use a formal fixation. The real impact of fibrin glue addition on chondrocytes migration and proliferation has not yet been clarified. This study evaluated the impact of fibrin glue on a chondrocyte loaded collagenic membrane.

METHODS

A resorbable collagen I/III porcine derived membrane commonly employed in AMIC was used for all experiments. Chondrocytes from three difference donors were used. At 1-, 2-, 3-, 4-, 6-, and at 8-week the membranes were embedded in Mounting Medium with Dapi (ABCAM, Cambridge, UK). The Dapi contained in the mounting medium ties the DNA of the cell nucleus and emits a blue fluorescence. In this way, the spreading of the cells in the membrane can be easily monitored. The outcomes of interest were to evaluate (1) cell migration and (2) cell proliferation within the porous membrane layer. DAPI/nuclei signals were analysed with fluorescence microscope under a magnification of 100-fold.

RESULTS

The no-fibrin group demonstrated greater migration of the cells within the membrane. Although migration resulted higher in the no-fibrin group at every follow-up, this difference was significant only at week 1 (P < 0.001), 2 (P = 0.004), and 3 (P = 0.03). No difference was found at week 3, 6, and 8. The no-fibrin group demonstrated greater proliferation of the chondrocytes within the membrane. These differences were significant at week 4 (P < 0.0001), 6 (P < 0.0001), 8 (P < 0.0001).

CONCLUSION

The use of fibrin glue over a resorbable membrane leads to lower in vitro proliferation and migration of chondrocytes.

The Use of Autologous Chondrocyte and Mesenchymal Stem Cell Implants for the Treatment of Focal Chondral Defects in Human Knee Joints-A Systematic Review and Meta-Analysis

Focal chondral defects of the knee occur commonly in the young, active population due to trauma. Damage can insidiously spread and lead to osteoarthritis with significant functional and socioeconomic consequences. Implants consisting of autologous chondrocytes or mesenchymal stem cells (MSC) seeded onto scaffolds have been suggested as promising therapies to restore these defects. However, the degree of integration between the implant and native cartilage still requires optimization. A PRISMA systematic review and meta-analysis was conducted using five databases (PubMed, MEDLINE, EMBASE, Web of Science, CINAHL) to identify studies that used autologous chondrocyte implants (ACI) or MSC implant therapies to repair chondral defects of the tibiofemoral joint. Data on the integration of the implant-cartilage interface, as well as outcomes of clinical scoring systems, were extracted. Most eligible studies investigated the use of ACI only. Our meta-analysis showed that, across a total of 200 patients, 64% (95% CI (51%, 75%)) achieved complete integration with native cartilage. In addition, a pooled improvement in the mean MOCART integration score was observed during post-operative follow-up (standardized mean difference: 1.16; 95% CI (0.07, 2.24), p = 0.04). All studies showed an improvement in the clinical scores. The use of a collagen-based scaffold was associated with better integration and clinical outcomes. This review demonstrated that cell-seeded scaffolds can achieve good quality integration in most patients, which improves over time and is associated with clinical improvements. A greater number of studies comparing these techniques to traditional cartilage repair methods, with more inclusion of MSC-seeded scaffolds, should allow for a standardized approach to cartilage regeneration to develop.

Matrix-induced autologous chondrocyte implantation (mACI) versus autologous matrix-induced chondrogenesis (AMIC) for chondral defects of the knee: a systematic review

INTRODUCTION

Chondral defects of the knee are common and their treatment is challenging.

SOURCE OF DATA

PubMed, Google scholar, Embase and Scopus databases.

AREAS OF AGREEMENT

Both autologous matrix-induced chondrogenesis (AMIC) and membrane-induced autologous chondrocyte implantation (mACI) have been used to manage chondral defects of the knee.

AREAS OF CONTROVERSY

It is debated whether AMIC and mACI provide equivalent outcomes for the management of chondral defects in the knee at midterm follow-up. Despite the large number of clinical studies, the optimal treatment is still controversial.

GROWING POINTS

To investigate whether AMIC provide superior outcomes than mACI at midterm follow-up.

AREAS TIMELY FOR DEVELOPING RESEARCH

AMIC may provide better outcomes than mACI for chondral defects of the knee. Further studies are required to verify these results in a clinical setting.

Chondral injuries in patients with recurrent patellar dislocation: a systematic review

Background

Patellar dislocations in patients presenting with recurrent patellofemoral instability can damage the surrounding structures, limiting patient’s participation to recreational activities and quality of life. This study evaluated frequency, location, and extent of associated injuries in patients with recurrent patellar dislocation.

Methods

This systematic review was conducted according to the PRISMA checklist. PubMed, Google scholar, Embase, and Web of Science databases were accessed in July 2021. All the published clinical studies reporting frequency, location, and extent of soft tissue lesions in patients with recurrent patellar dislocations were accessed.

Results

Data from 9 articles (232 patients) were retrieved. The mean age of the included patients was 21.2 ± 5.6 years. 84.8% of patients suffering from recurrent patellar dislocations demonstrated patellar chondral defects: medial facet (34.9%), while patellar crest (34.8%) and lateral facet (17%). 27.8% of patients demonstrated trochlear chondral injuries.

Conclusion

Chondral defects of the medial facet and the crest of the patella are the most common in patients with recurrent patellofemoral instability.

Meniscus regeneration by 3D printing technologies: Current advances and future perspectives

Meniscal tears are a frequent orthopedic injury commonly managed by conservative strategies to avoid osteoarthritis development descending from altered biomechanics. Among cutting-edge approaches in tissue engineering, 3D printing technologies are extremely promising guaranteeing for complex biomimetic architectures mimicking native tissues. Considering the anisotropic characteristics of the menisci, and the ability of printing over structural control, it descends the intriguing potential of such vanguard techniques to meet individual joints’ requirements within personalized medicine. This literature review provides a state-of-the-art on 3D printing for meniscus reconstruction. Experiences in printing materials/technologies, scaffold types, augmentation strategies, cellular conditioning have been compared/discussed; outcomes of pre-clinical studies allowed for further considerations. To date, translation to clinic of 3D printed meniscal devices is still a challenge: meniscus reconstruction is once again clear expression of how the integration of different expertise (e.g., anatomy, engineering, biomaterials science, cell biology, and medicine) is required to successfully address native tissues complexities.

Membrane scaffolds for matrix-induced autologous chondrocyte implantation in the knee: a systematic review

INTRODUCTION

Chondral defects of the knee are common and their management is challenging.

SOURCE OF DATA

Current scientific literature published in PubMed, Google scholar, Embase and Scopus.

AREAS OF AGREEMENT

Membrane-induced autologous chondrocyte implantation (mACI) has been used to manage chondral defects of the knee.

AREAS OF CONTROVERSY

Hyaluronic acid membrane provides better outcomes than a collagenic membrane for mACI in the knee at midterm follow-up is controversial.

GROWING POINTS

To investigate whether hyaluronic acid membrane may provide comparable clinical outcomes than collagenic membranes for mACI in focal defects of the knee.

AREAS TIMELY FOR DEVELOPING RESEARCH

Hyaluronic acid membrane yields a lower rate of failures and revision surgeries for mACI in the management of focal articular cartilage defects of the knee compared with collagenic scaffolds at midterm follow-up. No difference was found in patient reported outcome measures (PROMs). Further comparative studies are required to validate these results in a clinical setting.

Surgical management of focal chondral defects of the knee: a Bayesian network meta-analysis

Background

Focal chondral defects of the knee are common. Several surgical techniques have been proposed for the management of chondral defects: microfractures (MFX), osteochondral autograft transplantation (OAT), autologous matrix-induced chondrogenesis (AMIC) and autologous chondrocyte implantation (ACI)—first generation (pACI), second generation (cACI) and third generation (mACI). A Bayesian network meta-analysis was conducted to compare these surgical strategies for chondral defects in knee at midterm follow-up.

Methods

This Bayesian network meta-analysis was conducted according to the PRISMA extension statement for reporting of systematic reviews incorporating network meta-analyses of health care interventions. PubMed, Google Scholar, Embase and Scopus databases were accessed in July 2021. All the prospective comparative clinical trials investigating two or more surgical interventions for chondral defects of the knee were accessed. The network meta-analyses were performed through a Bayesian hierarchical random-effects model analysis. The log odds ratio (LOR) effect measures were used for dichotomic variables, while the standardized mean difference (SMD) for the continuous variables.

Results

Data from 2220 procedures (36 articles) were retrieved. The median follow-up was 36 (24 to 60) months. The ANOVA test found good baseline comparability between symptoms duration, age, sex and body mass index. AMIC resulted in higher Lysholm score (SMD 3.97) and Tegner score (SMD 2.10). AMIC demonstrated the lowest rate of failures (LOR −0.22) and the lowest rate of revisions (LOR 0.89). As expected, MFX reported the lower rate of hypertrophy (LOR −0.17) followed by AMIC (LOR 0.21). No statistically significant inconsistency was found in the comparisons.

Conclusion

AMIC procedure for focal chondral defects of the knee performed better overall at approximately 3 years’ follow-up.

Basic Research on Tendon Repair: Strategies, Evaluation, and Development

Tendon is a fibro-elastic structure that links muscle and bone. Tendon injury can be divided into two types, chronic and acute. Each type of injury or degeneration can cause substantial pain and the loss of tendon function. The natural healing process of tendon injury is complex. According to the anatomical position of tendon tissue, the clinical results are different. The wound healing process includes three overlapping stages: wound healing, proliferation and tissue remodeling. Besides, the healing tendon also faces a high re-tear rate. Faced with the above difficulties, management of tendon injuries remains a clinical problem and needs to be solved urgently. In recent years, there are many new directions and advances in tendon healing. This review introduces tendon injury and sums up the development of tendon healing in recent years, including gene therapy, stem cell therapy, Platelet-rich plasma (PRP) therapy, growth factor and drug therapy and tissue engineering. Although most of these therapies have not yet developed to mature clinical application stage, with the repeated verification by researchers and continuous optimization of curative effect, that day will not be too far away.

AMIC for traumatic focal osteochondral defect of the talar shoulder: a 5 years follow-up prospective cohort study

BACKGROUND

Autologous Matrix-Induced Chondrogenesis (AMIC) is addressed to osteochondral defects of the talus. However, evidence concerning the midterm efficacy and safety of AMIC are limited. This study assessed reliability and feasibility of AMIC at 60 months follow-up. We hypothesize that AMIC leads to good clinical outcome at midterm follow-up.

METHODS

Surgeries were approached with an arthrotomy via malleolar osteotomy. A resorbable porcine I/III collagen membrane (Chondro-Gide®, Geistlich Pharma AG, Wolhusen, Switzerland) was used. Patients were followed at 24 and 60 months. The primary outcome of interest was to analyse the Foot Function Index (FFI), and the subscale hindfoot of the American Orthopaedic Foot and Ankle Score (AOFAS). Complications such as failure, revision surgeries, graft delamination, and hypertrophy were also recorded. The secondary outcome of interest was to investigate the association between the clinical outcome and patient characteristics at admission.

RESULTS

Data from 19 patients were included. The mean age at admission was 47.3 ± 13.2 years, and the mean BMI 24.1 ± 4.9 kg/m². 53% (10 of 19 patients) were female. At a mean of 66.2 ± 11.6 months, the FFI decreased at 24-months follow-up of 22.5% (P = 0.003) and of further 1.3% (P = 0.8) at 60-months follow-up. AOFAS increased at 24-months follow-up of 17.2% (P = 0.003) and of further 3.4 (P = 0.2) at 60-months follow-up. There were two symptomatic recurrences within the follow-up in two patients. There was evidence of a strong positive association between FFI and AOFAS at baseline and the same scores last follow-up (P = 0.001 and P = 0.0002, respectively).

CONCLUSION

AMIC enhanced with cancellous bone graft demonstrated efficacy and feasibility for osteochondral defects of the talus at five years follow-up. The greatest improvement was evidenced within the first two years. These results suggest that clinical outcome is influenced by the preoperative status of the ankle. High quality studies involving a larger sample size are required to detect seldom complications and identify prognostic factors leading to better clinical outcome.

LEVEL OF EVIDENCE

II, prospective cohort study.

Ultrapurified Alginate Gel Containing Bone Marrow Aspirate Concentrate Enhances Cartilage and Bone Regeneration on Osteochondral Defects in a Rabbit Model

BACKGROUND

Ultrapurified alginate (UPAL) gel implantation has been demonstrated as effective in cartilage repair for osteochondral defects; however, cell transplantation within UPAL gels would be required to treat larger defects.

HYPOTHESIS

The combination of UPAL gel and bone marrow aspirate concentrate (BMAC) would enhance cartilage repair and subchondral bone repair for large osteochondral defects.

STUDY DESIGN

Controlled laboratory study.

METHODS

A total of 104 osteochondral defects (1 defect per knee) of 52 rabbits were randomly divided into 4 groups (26 defects per group): defects without any treatment (Defect group), defects treated using UPAL gel alone (UPAL group), defects treated using UPAL gel containing allogenic bone marrow mesenchymal stromal cells (UPAL-MSC group), and defects treated using UPAL gel containing BMAC (UPAL-BMAC group). At 4 and 16 weeks postoperatively, macroscopic and histologic evaluations and measurements of repaired subchondral bone volumes of reparative tissues were performed. Collagen orientation and mechanical properties of the reparative tissue were assessed at 16 weeks.

RESULTS

The defects in the UPAL-BMAC group were repaired with hyaline-like cartilage with well-organized collagen structures. The histologic scores at 4 weeks were significantly higher in the UPAL-BMAC group (16.9 ± 2.0) than in the Defect group (4.7 ± 1.9; P < .05), the UPAL group (10.0 ± 3.3; P < .05), and the UPAL-MSC group (12.2 ± 2.9; P < .05). At 16 weeks, the score in the UPAL-BMAC group (24.4 ± 1.7) was significantly higher than those in the Defect group (9.0 ± 3.7; P < .05), the UPAL group (14.2 ± 3.9; P < .05), and the UPAL-MSC group (16.3 ± 3.6; P < .05). At 4 and 16 weeks, the macroscopic evaluations were significantly superior in the UPAL-BMAC group compared with the other groups, and the values of repaired subchondral bone volumes in the UPAL-BMAC group were significantly higher than those in the Defect and UPAL groups. The mechanical properties of the reparative tissues were significantly better in the UPAL-BMAC group than in the other groups.

CONCLUSION

The implantation of UPAL gel containing BMAC-enhanced hyaline-like cartilage repair and subchondral bone repair of osteochondral defects in a rabbit knee model.

CLINICAL RELEVANCE

These data support the potential clinical application of 1-step treatment for large osteochondral defects using biomaterial implantation with cell transplantation.

Arthroscopy versus mini-arthrotomy approach for matrix-induced autologous chondrocyte implantation in the knee: a systematic review

BACKGROUND

Matrix-induced autologous chondrocyte implantation (mACI) can be performed in a full arthroscopic or mini-open fashion. A systematic review was conducted to investigate whether arthroscopy provides better surgical outcomes compared with the mini-open approach for mACI in the knee at midterm follow-up.

METHODS

This systematic review was conducted following the PRISMA guidelines. The literature search was performed in May 2021. All the prospective studies reporting outcomes after mACI chondral defects of the knee were accessed. Only studies that clearly stated the surgical approach (arthroscopic or mini-open) were included. Only studies reporting a follow-up longer than 12 months were eligible. Studies reporting data from combined surgeries were not eligible, nor were those combining mACI with less committed cells (e.g., mesenchymal stem cells).

RESULTS

Sixteen studies were included, and 770 patients were retrieved: 421 in the arthroscopy group, 349 in the mini-open. The mean follow-up was 44.3 (12-60) months. No difference between the two groups was found in terms of mean duration of symptoms, age, body mass index (BMI), gender, defect size (P > 0.1). No difference was found in terms of Tegner Score (P = 0.3), Lysholm Score (P = 0.2), and International Knee Documentation Committee (IKDC) Score (P = 0.1). No difference was found in the rate of failures (P = 0.2) and revisions (P = 0.06).

CONCLUSION

Arthroscopy and mini-arthrotomy approaches for mACI in knee achieve similar outcomes at midterm follow-up.

LEVEL OF EVIDENCE

II, systematic review of prospective studies.

Matrix-induced autologous chondrocyte implantation versus autologous matrix-induced chondrogenesis for chondral defects of the talus: a systematic review

INTRODUCTION

Chondral defects of the talus are common and their treatment is challenging.

SOURCE OF DATA

Recent published literatures.

AREAS OF AGREEMENT

Membrane-induced Autologous Chondrocyte Implantation (mACI) and Autologous Matrix-Induced Chondrogenesis (AMIC) have been proposed as management for chondral defects of the talus.

AREAS OF CONTROVERSY

It is debated whether AMIC provides greater outcomes compared to mACI for chondral regeneration. Several clinical studies showed controversial results, and the best treatment has not yet been clarified.

GROWING POINTS

To investigate whether AMIC provide superior outcomes than mACI at midterm follow-up.

AREAS TIMELY FOR DEVELOPING RESEARCH

AMIC exhibits similar clinical results to mACI. However, AMIC involves one single surgical procedure, no articular cartilage harvest and hence no morbidity from it, no need for chondrocyte expansion in a separate laboratory setting. For these reasons, AMIC may be preferred to mACI.

Autologous Matrix Induced Chondrogenesis (AMIC) Compared to Microfractures for Chondral Defects of the Talar Shoulder: A Five-Year Follow-Up Prospective Cohort Study

Introduction: Many procedures are available to manage cartilage defects of the talus, including microfracturing (MFx) and Autologous Matrix Induced Chondrogenesis (AMIC). Whether AMIC or MFx are equivalent for borderline sized defects of the talar shoulder is unclear. Thus, the present study compared the efficacy of primary isolated AMIC versus MFx for borderline sized focal unipolar chondral defects of the talar shoulder at midterm follow-up. Methods: Patients undergoing primary isolated AMIC or MFx for focal unipolar borderline sized chondral defects of the talar shoulder were recruited prospectively. For those patients who underwent AMIC, a type I/III collagen resorbable membrane was used. The outcomes of interest were: Visual Analogic Scale (VAS), Tegner Activity Scale, American Orthopedic Foot and Ankle Score (AOFAS). The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) was assessed by a blinded radiologist, who had not been involved in the clinical management of the patients. Data concerning complication rate and additional procedures were also collected. Results: The mean follow-up was 43.5 months. The mean age of the 70 patients at operation was 32.0 years, with a mean defect size of 2.7 cm². The mean length of hospitalization was shorter in the MFx cohort (p = 0.01). No difference was found between the two cohorts in terms of length of prior surgery symptoms and follow-up, mean age and BMI, sex and side, and defect size. At a mean follow-up of 43.5 months, the AOFAS (p = 0.03), VAS (p = 0.003), and Tegner (p = 0.01) scores were greater in the AMIC group. No difference was found in the MOCART score (p = 0.08). The AMIC group evidenced lower rates of reoperation (p = 0.008) and failure (p = 0.003). Conclusion: At midterm follow-up, AMIC provides better results compared to MFx.

Autologous Matrix-Induced Chondrogenesis (AMIC) and Microfractures for Focal Chondral Defects of the Knee: A Medium-Term Comparative Study

Introduction: The potential of autologous matrix-induced chondrogenesis (AMIC) to restore unipolar focal chondral defects of the knee is promising. However, the outcome compared to microfracturing (MFx) for certain defect sizes (2–3 cm²) is still uncertain. Therefore, the present study compared primary isolated AMIC versus MFx in a cohort of patients with borderline sized focal unipolar chondral defects of the knee at midterm follow-up. Methods: Patients with chondral defects of the knee who underwent AMIC or MFx were compared. An arthroscopic approach was used for MFx, and a minimally invasive parapatellar arthrotomy for AMIC. For those patients who underwent AMIC, a collagen membrane was used with fibrin glue. The patients answered independently: Visual Analogic Scale (VAS), Tegner Activity Scale, International Knee Documentation Committee (IKDC), and the Lysholm scores. Results: A total of 83 patients with a mean age of 30.2 and body mass index (BMI) of 26.9 kg/m² were recruited. Of them, 33.7% (28 of 83) were women, and 55.4% (46 of 83 patients) had defects in the right knee. The mean length of symptoms before surgery was 43.3 months. The mean size of the defect was 2.7 cm². The mean length of follow-up was 42.1 months. No difference was found in terms of symptoms and follow-up length, mean age and BMI, mean size of defect, sex, and side. The AMIC cohort reported greater IKCD (p > 0.0001), Lysholm (p = 0.002), VAS (p = 0.01), Tegner (p = 0.004) scores. The AMIC cohort reported lower rate of failure (p = 0.005) and revision surgery (p = 0.02). No difference was found in the rate of arthroplasty (p = 0.2). No delamination or hypertrophy were detected. Conclusion: AMIC demonstrated superiority over MFx for focal unipolar chondral defects of the knee. At approximately 40 months follow-up, the IKDC, Lysholm, and VAS scores were greater in the AMIC group. Patients treated with AMIC also demonstrated a higher level of sport activity, and lower rates of failure and revision surgeries.

Management of Patellar Chondral Defects with Autologous Matrix Induced Chondrogenesis (AMIC) Compared to Microfractures: A Four Years Follow-Up Clinical Trial

Introduction: Evidence on the management of chondral defects of the patella arises from studies in which the patellofemoral joint was treated together with the femorotibial joint and primary and revision settings. Furthermore, the superiority of Autologous Matrix Induced Chondrogenesis (AMIC) over microfractures (MFx) for patellar chondral defects is uncertain. Therefore, the present study compared primary isolated AMIC versus MFx for focal unipolar chondral defects of the patellar facet joints at midterm follow-up. Methods: Patients undergoing AMIC or isolated MFx surgery for borderline-sized focal unipolar chondral defects of the patellar facet joints were followed at our institution. All surgeries were performed in the same fashion by experienced surgeons. A parapatellar arthrotomy was adopted in all surgeries. The outcomes of interest were: Visual Analogic Scale (VAS), Tegner Activity Scale, International Knee Documentation Committee (IKDC), and the Lysholm scores. The Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) was assessed by a blinded radiologist, who had not been involved in the clinical management of the patients. Results: 38 patients were enrolled in the present study: 27 underwent AMIC, and 11 MFx. The mean follow-up was 45.1 months. The mean age of the patients at baseline was 34.5 years. The mean size of the defect was 2.6 cm². The MFx cohort experienced a shorter length of the hospitalization (P = 0.008). There was no difference in terms of follow-up and previous symptoms duration, mean age, sex, side, defect size, and BMI. At last follow-up, the AMIC cohort reported greater IKDC (P = 0.01), Lysholm (P = 0.009), and Tegner (P = 0.02), along with a low rate of failure (P = 0.02). VAS was lower in the AMIC group (P = 0.002). No difference was found in the MOCART score (P = 0.09), rates of revision (P = 0.06), and arthroplasty (P = 0.2). Conclusion: The AMIC procedure achieves greater IKDC and Lysholm score, and a significant reduction of the VAS score in the management of patellar chondral defects. The Tegner scale demonstrated greater activity after AMIC procedure. Finally, the AMIC group evidenced a lower rate of failure. Similarity was found on MOCART score, rates of revision, and arthroplasty between the two procedures.

AMIC for Focal Osteochondral Defect of the Talar Shoulder

BACKGROUND

The management of a focal osteochondral lesion of the talus (OLT) is challenging. Evidence concerning the role of the autologous matrix-induced chondrogenesis (AMIC) procedure in patients with focal OLT is promising. The purpose of the present study was to investigate clinical outcomes and radiographic findings of the AMIC technique for focal unipolar OLT.

MATERIAL AND METHODS

The present study was performed according to the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) guidelines. Twenty-four patients who underwent AMIC for focal OLT were prospectively recruited at our institution. All the surgeries were performed by two experienced surgeons through malleolar osteotomy and autologous cancellous bone grafting. The outcomes of interest were the American orthopedic foot and ankle score (AOFAS), the foot-function index (FFI), and the magnetic resonance observation of cartilage repair tissue (MOCART). Surgical duration, hospitalization length, and complications were also collected.

RESULTS

24 patients were included in the present study. The mean follow-up was 25.17 ± 13.1 months. The mean age of the patients at surgery was 46.75 ± 15.2 years, the mean BMI 26.92 ± 5.7 kg/m², and 50% (12 of 24) of patients were female. The right ankle was involved in 62.5% (15 of 24) of patients. The mean defect size was 6.95 ± 2.9 mm². The mean surgical duration was 112 ± 20 min while the mean hospitalization 5.58 ± 1.7 days. At last follow-up, the AOFAS increased by 27.8 points (p < 0.0001), while the FFI reduced by 25.3 points (p < 0.0001) and the MOCART score increased by 28.33 points (p < 0.0001). No complications were observed.

CONCLUSION

The AMIC procedure for focal osteochondral defects of the talar shoulder is feasible and reliable at midterm follow-up.

Encouraging cartilage production

A long non-coding RNA called GRASLND is essential to help stem cells create stable cartilage.