Single-Stage Autologous Chondrocyte-Based Treatment for the Repair of Knee Cartilage Lesions: Two-Year Follow-up of a Prospective Single-Arm Multicenter Study

Treatment of Articular Cartilage Defects: A Descriptive Analysis of Clinical Characteristics and Global Trends Reported from 2001 to 2020

PURPOSE

To evaluate the clinical characteristics and global trends in the surgical treatment of articular cartilage defects.

METHODS

Studies in English published between January 1, 2001 and December 31, 2020 were retrieved from MEDLINE, WOS, INSPEC, SCIELO, KJD, and RSCI on the "Web of Science." Patient data were extracted, including age, sex, defect location and laterality, duration of follow-up and symptoms, and body mass index (BMI). Data were further stratified according to the surgical method, lesion location, procedural type and geographical area, and time period. A comparative analysis was performed.

RESULTS

Overall, 443 studies involving 26,854 patients (mean age, 35.25 years; men, 60.5%) were included. The mean lesion size and patient BMI were 3.51 cm2 and 25.61 kg/m2, respectively. Cartilage defects at the knees, talus, and hips affected 20,850 (77.64%), 3,983 (14.83%), and 1,425 (5.31%) patients, respectively. The numbers of patients who underwent autologous chondrocyte implantation, arthroscopic debridement/chondroplasty, osteochondral allograft (OCA), osteochondral autologous transplantation, and microfracture were 7,114 (26.49%), 5,056 (18.83%), 3,942 (14.68%), 3,766 (14.02%), and 2,835 (10.56%), respectively. European patients were the most numerous and youngest. North American patients had the largest defects. The number of patients increased from 305 in 2001 to 3,017 in 2020. In the last 5 years, the frequency of OCAs showed a greatly increasing trend.

CONCLUSION

Clinical characteristics and global trends in the surgical treatment of articular cartilage defects were revealed. The choice of operation should be based on the patient characteristics and defect location, size, and shape, as well as the patient's preference.

Latest Advances in Chondrocyte-Based Cartilage Repair

Chondrocyte-based cell therapy has been used for more than 30 years and is still considered to be a promising method of cartilage repair despite some limitations. This review introduces the latest developments of four generations of autologous chondrocyte implantation and current autologous chondrocyte products. The regeneration of cartilage from adult chondrocytes is limited by culture-induced dedifferentiation and patient age. Cartibeads is an innovative three-step method to produce high-quality hyaline cartilage microtissues, and it is developed from adult dedifferentiated chondrocytes with a high number of cell passages. In addition, allogeneic chondrocyte therapies using the Quantum hollow-fiber bioreactor and several signaling pathways involved in chondrocyte-based cartilage repair are mentioned, such as WNT signaling, the BMP-2/WISP1 pathway, and the FGF19 pathway.

Treatment of knee cartilage lesions in 2024: From hyaluronic acid to regenerative medicine

Abstract

Intact articular cartilage plays a vital role in joint homeostasis. Local cartilage repairs, where defects in the cartilage matrix are filled in and sealed to congruity, are therefore important treatments to restore a joint equilibrium. The base for all cartilage repairs is the cells; either chondrocytes or chondrogeneic cells from bone, synovia and fat tissue. The surgical options include bone marrow stimulation techniques alone or augmented with scaffolds, chondrogeneic cell implantations and osteochondral auto- or allografts. The current trend is to choose one-stage procedures being easier to use from a regulatory point of view. This narrative review provides an overview of the current nonoperative and surgical options available for the repair of various cartilage lesions.

Level of Evidence

Level IV.

Three-Dimensional Bioprinting in Soft Tissue Engineering for Plastic and Reconstructive Surgery

Skeletal muscle tissue engineering (TE) and adipose tissue engineering have undergone significant progress in recent years. This review focuses on the key findings in these areas, particularly highlighting the integration of 3D bioprinting techniques to overcome challenges and enhance tissue regeneration. In skeletal muscle TE, 3D bioprinting enables the precise replication of muscle architecture. This addresses the need for the parallel alignment of cells and proper innervation. Satellite cells (SCs) and mesenchymal stem cells (MSCs) have been utilized, along with co-cultivation strategies for vascularization and innervation. Therefore, various printing methods and materials, including decellularized extracellular matrix (dECM), have been explored. Similarly, in adipose tissue engineering, 3D bioprinting has been employed to overcome the challenge of vascularization; addressing this challenge is vital for graft survival. Decellularized adipose tissue and biomimetic scaffolds have been used as biological inks, along with adipose-derived stem cells (ADSCs), to enhance graft survival. The integration of dECM and alginate bioinks has demonstrated improved adipocyte maturation and differentiation. These findings highlight the potential of 3D bioprinting techniques in skeletal muscle and adipose tissue engineering. By integrating specific cell types, biomaterials, and printing methods, significant progress has been made in tissue regeneration. However, challenges such as fabricating larger constructs, translating findings to human models, and obtaining regulatory approvals for cellular therapies remain to be addressed. Nonetheless, these advancements underscore the transformative impact of 3D bioprinting in tissue engineering research and its potential for future clinical applications.

Single-stage autologous cartilage repair results in positive patient-reported outcomes for chondral lesions of the knee: a systematic review

AIM

This article aims to perform a systematic review of the clinical literature regarding the efficacy of single-stage autologous cartilage repair.

METHODS

A systematic review of the literature was performed using PubMed, Scopus, Web of Science, and the Cochrane Library. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed.

RESULTS

Twelve studies were identified; however, due to overlapping patient cohorts, nine studies were included for data extraction and analysis. Six studies applied minced cartilage, while three studies utilized enzymatically processed cartilage. Two authorship groups described single-stage techniques that exclusively utilized cartilage from the debrided lesion rim, while the remaining groups either utilized healthy cartilage or combined healthy cartilage with cartilage debrided from lesion rim. Among the included techniques, scaffold augments were used in four studies, and three studies implemented bone autograft augmentation. When summarizing patient reported outcome measures for the included studies, single-stage autologous cartilage repair demonstrated an average improvement ranging from 18.7 ​± ​5.3 to 30.0 ​± ​8.0 amongst the Knee Injury and Osteoarthritis Outcome Scores subsections, 24.3 ​± ​10.5 for the International Knee Documentation Committee subjective score, and 41.0 ​± ​10.0 for Visual Analogue Scale-Pain.

CONCLUSION

Single-stage autologous cartilage repair is a promising technique with positive clinical data to date. The current study highlights the overall improvement in patient reported outcomes after repair for chondral defects to the knee with average follow-up ranging from 12 to 201 months and also the heterogeneity and variability of the single-stage surgical technique. Further discussion on the standardization of practices for a cost-effective single-stage augmented autologous cartilage technique is needed. In the future, a well-designed randomized controlled trial is needed to explore the efficacy of this therapeutic modality relative to established intervention.

LEVEL OF EVIDENCE

Systematic review; Level IV.

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.

Within or Without You? A Perspective Comparing In Situ and Ex Situ Tissue Engineering Strategies for Articular Cartilage Repair

Human articular cartilage has a poor ability to self-repair, meaning small injuries often lead to osteoarthritis, a painful and debilitating condition which is a major contributor to the global burden of disease. Existing clinical strategies generally do not regenerate hyaline type cartilage, motivating research toward tissue engineering solutions. Prospective cartilage tissue engineering therapies can be placed into two broad categories: i) Ex situ strategies, where cartilage tissue constructs are engineered in the lab prior to implantation and ii) in situ strategies, where cells and/or a bioscaffold are delivered to the defect site to stimulate chondral repair directly. While commonalities exist between these two approaches, the core point of distinction-whether chondrogenesis primarily occurs "within" or "without" (outside) the body-can dictate many aspects of the treatment. This difference influences decisions around cell selection, the biomaterials formulation and the surgical implantation procedure, the processes of tissue integration and maturation, as well as, the prospects for regulatory clearance and clinical translation. Here, ex situ and in situ cartilage engineering strategies are compared: Highlighting their respective challenges, opportunities, and prospects on their translational pathways toward long term human cartilage repair.

Single-Surgery Co-Implantation of Autologous Primary Articular Chondrocytes with Bone Marrow Cells in the Treatment of Articular Cartilage Lesions: Observations from the Operating Room on Tissue Input and Cell Output

OBJECTIVE

Single-surgery variants of autologous chondrocyte implantation to repair cartilage are emerging, but practical data on such procedures are scarce. We set out to describe a 1-stage autologous chondrocyte co-implantation procedure and include quantitative characteristics of the biopsy tissues collected and of the cells obtained from those tissues in the operating room.

DESIGN

Data concerning patient age, articular cartilage lesion size and location, as well as measurements of cartilage biopsy mass, bone marrow aspirate volume, and the cell yields harvested from those biopsies were intraoperatively collected for 141 patients.

RESULTS

The mean patient age was 35.7 ± 9.8 years, and the mean total lesion size was 4.0 ± 3.1 cm². Cartilage biopsy mass ranged from 0.19 to 2.0 gram and provided a mean yield of 1.23 × 10⁶ chondrocytes/gram. Bone marrow aspirate volume ranged from 7.2 to 62 milliliters and provided a mean yield of 7.18 × 10⁶ mononuclear cells/mL. The cell yields did not correlate with patient age, which ranged from 12 to 57 years. The mean primary chondrocyte supply was 272 thousand per cm² of lesion, ranging from 10.4 thousand to 1.07 million per cm². The total cell supply was kept at 9 million cells per cm² of lesion by adding mononuclear cells to the chondrocytes. The mean tissue processing time was 100 ± 19 minutes, which was frequently used to perform concurrent interventions.

CONCLUSION

Single-surgery co-implantation of clinically relevant numbers of autologous primary articular chondrocytes and bone marrow cells is feasible for a wide range of ages and lesion sizes.

In Vitro and Ectopic In Vivo Studies toward the Utilization of Rapidly Isolated Human Nasal Chondrocytes for Single-Stage Arthroscopic Cartilage Regeneration Therapy

Nasal chondrocytes (NCs) have a higher and more reproducible chondrogenic capacity than articular chondrocytes, and the engineered cartilage tissue they generate in vitro has been demonstrated to be safe in clinical applications. Here, we aimed at determining the feasibility for a single-stage application of NCs for cartilage regeneration under minimally invasive settings. In particular, we assessed whether NCs isolated using a short collagenase digestion protocol retain their potential to proliferate and chondro-differentiate within an injectable, swiftly cross-linked and matrix-metalloproteinase (MMP)-degradable polyethylene glycol (PEG) gel enriched with human platelet lysate (hPL). NC-hPL-PEG gels were additionally tested for their capacity to generate cartilage tissue in vivo and to integrate into cartilage/bone compartments of human osteochondral plugs upon ectopic subcutaneous implantation into nude mice. NCs isolated with a rapid protocol and embedded in PEG gels with hPL at low cell density were capable of efficiently proliferating and of generating tissue rich in glycosaminoglycans and collagen II. NC-hPL-PEG gels developed into hyaline-like cartilage tissues upon ectopic in vivo implantation and integrated with surrounding native cartilage and bone tissues. The delivery of NCs in PEG gels containing hPL is a feasible strategy for cartilage repair and now requires further validation in orthotopic in vivo models.

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.

Insights into the present and future of cartilage regeneration and joint repair

Knee osteoarthritis is the most common joint disease. It causes pain and suffering for affected patients and is the source of major economic costs for healthcare systems. Despite ongoing research, there is a lack of knowledge regarding disease mechanisms, biomarkers, and possible cures. Current treatments do not fulfill patients' long-term needs, and it often requires invasive surgical procedures with subsequent long periods of rehabilitation. Researchers and companies worldwide are working to find a suitable cell source to engineer or regenerate a functional and healthy articular cartilage tissue to implant in the damaged area. Potential cell sources to accomplish this goal include embryonic stem cells, mesenchymal stem cells, or induced pluripotent stem cells. The differentiation of stem cells into different tissue types is complex, and a suitable concentration range of specific growth factors is vital. The cellular microenvironment during early embryonic development provides crucial information regarding concentrations of signaling molecules and morphogen gradients as these are essential inducers for tissue development. Thus, morphogen gradients implemented in developmental protocols aimed to engineer functional cartilage tissue can potentially generate cells comparable to those within native cartilage. In this review, we have summarized the problems with current treatments, potential cell sources for cell therapy, reviewed the progress of new treatments within the regenerative cartilage field, and highlighted the importance of cell quality, characterization assays, and chemically defined protocols.

Repairing Cartilage with Processed Chondrocyte Constructs: A 6-Month Study Using a Porcine Model

OBJECTIVE

Autologous chondrocyte implantation was the first cell-based therapy that used a tissue engineering process to repair cartilage defects. Recently improved approaches and tissue-engineered cell constructs have been developed for growing patient populations. We developed a chondrocyte construct using a collagen gel and sponge scaffold and physicochemical stimuli, implanted with a surgical adhesive. We conducted a proof-of-concept study of these improvements using a cartilage defect model in miniature swine.

DESIGN

We implanted the autologous chondrocyte constructs into full-thickness chondral defects in the femoral condyle, compared those results with empty and acellular scaffold controls, and compared implantation techniques with adhesive alone and with partial adhesive with suture. Two weeks after the creation of the defects and implantation of the cellular or acellular constructs, we arthroscopically confirmed that the implanted constructs remained at the chondral defects. We evaluated the regenerated tissue macro- and microscopically 6 months after the cell constructs were implanted. The tissues were stained with Safranin-O and evaluated using Sellers' histology grading system.

RESULTS

The defects implanted with processed cell constructs and acellular scaffolds were filled with chondrocyte-like round cells and with nearly normal tissue architecture that were significantly greater degree compared to empty defect control. Even with the adhesive alone and with suture alone, the cell construct was composed of the dense cartilaginous matrix that was found in the implantation using both the sutures and the adhesive.

CONCLUSION

Implantation of cell constructs promoted regeneration and integration of articular cartilage at chondral defects in swine by 6 months.

Chondroinductive Peptides for Cartilage Regeneration

Inducing and maintaining a hyaline cartilage phenotype is the greatest challenge for cartilage regeneration. Synthetic chondroinductive biomaterials might be the answer to the unmet clinical need for a safe, stable, and cost-effective material capable of inducing true hyaline cartilage formation. The past decade witnessed an emergence of peptides to achieve chondrogenesis, as peptides have the advantages of versatility, high target specificity, minimized toxicity and immunogenicity, and ease of synthesis. Here, we review peptides as the basis for creating promising synthetic chondroinductive biomaterials for in situ scaffold-based cartilage regeneration. We provide a thorough review of peptides evaluated for cartilage regeneration while distinguishing between peptides reported to induce chondrogenesis independently, and peptides reported to act in synergy with other growth factors to induce cartilage regeneration. Additionally, we highlight that most peptide studies have been in vitro, and appropriate controls are not always present. A few rigorously-performed in vitro studies have proceeded to in vivo studies, but the peptides in those in vivo studies were mainly introduced via systemic, subcutaneous, or intraarticular injections, with a paucity of studies employing in situ defects with appropriate controls. Clinical translation of peptides will require the evaluation of these peptides in well-controlled in vivo cartilage defect studies. In the decade ahead, we may be poised to leverage peptides to design devices that are safe, reproducible, cost-efficient, and scalable biomaterials, which are themselves chondroinductive to achieve true hyaline cartilage regeneration without the need for growth factors and other small molecules.

Five-Year Outcome of 1-Stage Cell-Based Cartilage Repair Using Recycled Autologous Chondrons and Allogenic Mesenchymal Stromal Cells: A First-in-Human Clinical Trial

BACKGROUND

Long-term clinical evaluation of patient outcomes can steer treatment choices and further research for cartilage repair. Using mesenchymal stromal cells (MSCs) as signaling cells instead of stem cells is a novel approach in the field.

PURPOSE

To report the 5-year follow-up of safety, clinical efficacy, and durability after treatment of symptomatic cartilage defects in the knee with allogenic MSCs mixed with recycled autologous chondrons in first-in-human study of 1-stage cartilage repair.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

This study is an investigator-driven study aiming at the feasibility and safety of this innovative cartilage repair procedure. Between 2013 and 2014, a total of 35 patients (mean ± SD age, 36 ± 8 years) were treated with a 1-stage cartilage repair procedure called IMPACT (Instant MSC Product Accompanying Autologous Chondron Transplantation) for a symptomatic cartilage defect on the femoral condyle or trochlear groove. Subsequent follow-up after initial publication was performed annually using online patient-reported outcome measures with a mean follow-up of 61 months (range, 56-71 months). Patient-reported outcome measures included the KOOS (Knee injury and Osteoarthritis Outcome Score), visual analog scale for pain, and EuroQol-5 Dimensions. All clinical data and serious adverse events, including additional treatment received after IMPACT, were recorded. A failure of IMPACT was defined as a chondral defect of at least 20% of the index lesion with a need for a reintervention including a surgical procedure or an intra-articular injection.

RESULTS

Using allogenic MSCs, no signs of a foreign body response or serious adverse reactions were recorded after 5 years. The majority of patients showed statistically significant and clinically relevant improvement in the KOOS and all its subscales from baseline to 60 months: overall, 57.9 ± 16.3 to 78.9 ± 17.7 (P < .001); Pain, 62.3 ± 18.9 to 79.9 ± 20.0 (P = .03); Function, 61.6 ± 16.5 to 79.4 ± 17.3 (P = .01); Activities of Daily Living, 69.0 ± 19.0 to 89.9 ± 14.9 (P < .001); Sports and Recreation, 32.3 ± 22.6 to 57.5 ± 30.0 (P = .02); and Quality of Life, 25.9 ± 12.9 to 55.8 ± 26.8 (P < .001). The visual analog scale score for pain improved significantly from baseline (45.3 ± 23.6) to 60 months (15.4 ± 13.4) (P < .001). Five cases required reintervention.

CONCLUSION

This is the first study showing the midterm safety and efficacy of the proof of concept that allogenic MSCs augment 1-stage articular cartilage repair. The absence of serious adverse events and the clinical outcome support the longevity of this unique concept. These data support MSC-augmented chondron transplantation (IMPACT) as a safe 1-stage surgical solution that is considerably more cost-effective and a logistically advantageous alternative to conventional 2-stage cell-based therapy for articular chondral defects in the knee.

Measuring Outcomes in Knee Articular Cartilage Pathology

Measuring outcomes following treatment of knee articular cartilage lesions is crucial to determine the natural history of disease and the efficacy of treatments. Outcome assessments for articular cartilage treatments can be clinical (based on failure, lack of healing, reoperation, need for arthroplasty), radiographic (X-ray, MRI), histologic, or patient reported and functional. The purpose of this review is to discuss the application and properties of patient-reported outcomes (PROs) with a focus on articular cartilage injuries and surgery in the knee. The most frequently used and validated PROs for knee articular cartilage studies include: the Knee injury and Osteoarthritis and Outcome Score, International Knee Documentation Committee Subjective Knee Form, and Lysholm score as knee-specific measures; the Marx Activity Rating Scale and Tegner Activity Scale as activity measures; and EQ-5D and SF-36/12 as generic quality-of-life measures. Incorporating these validated PROs in studies pertaining to knee articular cartilage lesions will allow researchers to fully capture clinically relevant outcomes that are most important to patients.

Regenerative Potential of Mandibular Condyle Cartilage and Bone Cells Compared to Costal Cartilage Cells When Seeded in Novel Gelatin Based Hydrogels

The field of temporomandibular joint (TMJ) condyle regeneration is hampered by a limited understanding of the phenotype and regeneration potential of cells in mandibular condyle cartilage. It has been shown that chondrocytes derived from hyaline and costal cartilage exhibit a greater chondro-regenerative potential in vitro than those from mandibular condylar cartilage. However, our recent in vivo studies suggest that mandibular condyle cartilage cells do have the potential for cartilage regeneration in osteochondral defects, but that bone regeneration is inadequate. The objective of this study was to determine the regeneration potential of cartilage and bone cells from goat mandibular condyles in two different photocrosslinkable hydrogel systems, PGH and methacrylated gelatin, compared to the well-studied costal chondrocytes. PGH is composed of methacrylated poly(ethylene glycol), gelatin, and heparin. Histology, biochemistry and unconfined compression testing was performed after 4 weeks of culture. For bone derived cells, histology showed that PGH inhibited mineralization, while gelatin supported it. For chondrocytes, costal chondrocytes had robust glycosaminoglycan (GAG) deposition in both PGH and gelatin, and compression properties on par with native condylar cartilage in gelatin. However, they showed signs of hypertrophy in gelatin but not PGH. Conversely, mandibular condyle cartilage chondrocytes only had high GAG deposition in gelatin but not in PGH. These appeared to remain dormant in PGH. These results show that mandibular condyle cartilage cells do have innate regeneration potential but that they are more sensitive to hydrogel material than costal cartilage cells.