Clinical outcome and success rates of ACI for cartilage defects of the patella: a subgroup analysis from a controlled randomized clinical phase II trial (CODIS study)

Treatment of cartilage defects in the patellofemoral joint with matrix-associated autologous chondrocyte implantation effectively improves pain, function, and radiological outcomes after 5-7 years

INTRODUCTION

The aim of the present study was to evaluate midterm outcomes 5-7 years after matrix-associated autologous chondrocyte implantation (MACI) in the patellofemoral joint.

MATERIALS AND METHODS

Twenty-six patients who had undergone MACI using the Novocart® 3D scaffold were prospectively evaluated. Clinical outcomes were determined by measuring the 36-Item Short-Form Health Survey (SF-36) and International Knee Documentation Committee (IKDC) scores and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) values preoperatively and 3, 6, and 12 months, and a mean of 6 years postoperatively. At the final follow-up, the Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) score was evaluated.

RESULTS

Twenty-two patients with 23 focal cartilage defects (19 patella and four trochlea) were available for the final follow-up. The mean defect size was 4.0 ± 1.9 cm2 (range 2.4-9.4 cm2). All clinical outcome scores improved significantly until 5-7 years after MACI (SF-36 score, 61.2 ± 19.6 to 83.2 ± 11.6; P = 0.001; IKDC score, 47.5 ± 20.6 to 74.7 ± 15.5; P < 0.001; and WOMAC, 29.8 ± 15.7 to 8.2 ± 10.3; P < 0.001). The mean MOCART score was 76.0 ± 11.0 at the final follow-up. Nineteen of the 22 patients (86.4%) were satisfied with the outcomes after 5-7 years and responded that they would undergo the procedure again.

CONCLUSION

MACI in the patellofemoral joint demonstrated good midterm clinical results with a significant reduction in pain, improvement in function, and high patient satisfaction. These clinical findings are supported by radiological evidence from MOCART scores.

LEVEL OF EVIDENCE

IV-case series.

Clinical Applicability of Autologous Chondrocyte Implantation for the Treatment of Osteochondral Defects: A Meta-analysis

PURPOSE

Osteoarthritis and other joint disorders are the leading cause of disability in the elderly and the treatment of joint lesions is challenging. Autologous chondrocyte implantation (ACI) has been reported with variable effects for the treatment of osteochondral and other joint lesions. In this study, we performed a meta-analysis of the recent literature to determine the clinical applicability of ACI for osteochondral defects.

METHODS

A meta-analysis was performed on the recent literature showing the effects of ACI on osteochondral defects. The PUBMED, ScienceDirect and Google Scholar databases were used to identify eligible studies from Jan 2010 to Sep 2022. Both fixed and random models of meta-analysis were applied with all reported scoring systems to quantify the effectiveness of ACI on osteochondral defects.

RESULTS

The pool data of 965 patients as a case series after ACI from a fixed model showed a significant improvement in the osteochondral defects (odds ratio = 8.75, 95%CI = 7.127 to 10.743, p = 0.000). These results were further verified by a random model of meta-analysis. The data also showed a substantial heterogeneity among the studies used in the meta-analysis (Q-value = 160.41, I-squared = 87.53, p = 0.000). Furthermore, this meta-analysis also compared different ACI procedures with different scoring systems but the overall outcome remains the same as ACI was found to be useful for the healing of the osteochondral defects.

CONCLUSION

This meta-analysis of 965 case series revealed that the ACI markedly improved the damage osteochondral defects scores but the optimal treatment is still controversial, therefore further studies are needed to validate these findings in a clinical setting.

Comparison of Hydrogel-Based Autologous Chondrocyte Implantation Versus Microfracture: A Propensity Score Matched-Pair Analysis

Background

Few studies exist for large defects comparing matrix-associated autologous chondrocyte implantation (M-ACI) with other cartilage repair methods due to the limited availability of suitable comparator treatments.

Purpose

To compare the clinical efficacy of a novel hydrogel-based M-ACI method (NOVOCART Inject plus) versus microfracture (MFx) in patients with knee cartilage defects.

Study Design

Cohort study; Level of evidence, 3.

Methods

Propensity score matched-pair analysis was used to compare the 24-month outcomes between the M-ACI treatment group from a previous single-arm phase 3 study and the MFx control group from another phase 3 study. Patients were matched based on preoperative Knee injury and Osteoarthritis Outcomes Score (KOOS), symptom duration, previous knee surgeries, age, and sex, resulting in 144 patients in the matched-pair set (72 patients per group). The primary endpoint was the change in least-squares means (ΔLSmeans) for the KOOS from baseline to the 24-month assessment.

Results

Defect sizes in the M-ACI group were significantly larger than in the MFx group (6.4 versus 3.7 cm2). Other differences included defect location (no patellar or tibial defects in the MFx group), number of defects (33.3% with 2 defects in the M-ACI group versus 9.7% in the MFx group), and defect cause (more patients with degenerative lesions in the M-ACI group). The M-ACI group had higher posttreatment KOOS (M-ACI versus MFX: 81.8 ± 16.8 versus 73.0 ± 20.6 points) and KOOS ΔLSmeans from baseline to 24 months posttreatment (M-ACI versus MFX: 36.9 versus 26.9 points). Treatment contrasts in KOOS ΔLSmeans from baseline indicated statistical significance in favor of M-ACI from 3 to 24 months posttreatment (P = .0026). Significant and clinically meaningful differences in favor of M-ACI at 24 months were also found regarding International Knee Documentation Committee (IKDC) score ΔLSmeans from baseline (37.8 versus 30.4 points; P = .0334), KOOS responder rates at 24 months (≥10-point improvement from baseline; 94.4% versus 65.3%; P < .0001), IKDC responder rates at 24 months (>20.5-point improvement from baseline; 83.3% versus 61.1%, P = .0126) and MOCART (Magnetic Resonance Observation of Cartilage Repair Tissue) score in a subgroup of patients (LS means, 86.9 versus 69.1; P = .0096).

Conclusion

In this exploratory analysis, M-ACI using an in situ crosslinked hydrogel demonstrated superior clinical and structural (MOCART) 24-month outcomes compared with MFx in patients with knee cartilage defects.

Bone Marrow MSC Secretome Increases Equine Articular Chondrocyte Collagen Accumulation and Their Migratory Capacities

Equine osteoarthritis (OA) leads to cartilage degradation with impaired animal well-being, premature cessation of sport activity, and financial losses. Mesenchymal stem cell (MSC)-based therapies are promising for cartilage repair, but face limitations inherent to the cell itself. Soluble mediators and extracellular vesicles (EVs) secreted by MSCs are the alternatives to overcome those limitations while preserving MSC restorative properties. The effect of equine bone marrow MSC secretome on equine articular chondrocytes (eACs) was analyzed with indirect co-culture and/or MSC-conditioned media (CM). The expression of healthy cartilage/OA and proliferation markers was evaluated in eACs (monolayers or organoids). In vitro repair experiments with MSC-CM were made to evaluate the proliferation and migration of eACs. The presence of nanosized EVs in MSC-CM was appraised with nanoparticle tracking assay and transmission electron microscopy. Our results demonstrated that the MSC secretome influences eAC phenotype by increasing cartilage functionality markers and cell migration in a greater way than MSCs, which could delay OA final outcomes. This study makes acellular therapy an appealing strategy to improve equine OA treatments. However, the MSC secretome contains a wide variety of soluble mediators and small EVs, such as exosomes, and further investigation must be performed to understand the mechanisms occurring behind these promising effects.

Safety and Efficacy of Matrix-Associated Autologous Chondrocyte Implantation With Spheroids for Patellofemoral or Tibiofemoral Defects: A 5-Year Follow-up of a Phase 2, Dose-Confirmation Trial

Background:

Matrix-associated autologous chondrocyte implantation (ACI) is a well-established treatment for cartilage defects. High-level evidence at midterm follow-up is limited, especially for ACI using spheroids (spherical aggregates of ex vivo expanded human autologous chondrocytes and self-synthesized extracellular matrix).

Purpose:

To assess the safety and efficacy of 3-dimensional matrix-associated ACI using spheroids to treat medium to large cartilage defects on different locations in the knee joint (patella, trochlea, and femoral condyle) at 5-year follow-up.

Study Design:

Cohort study; Level of evidence, 2.

Methods:

A total of 75 patients aged 18 to 50 years with medium to large (4-10 cm²), isolated, single cartilage defects, International Cartilage Repair Society grade 3 or 4, were randomized on a single-blind basis to treatment with ACI at 1 of 3 dose levels: 3 to 7, 10 to 30, or 40 to 70 spheroids/cm² of defect size. Outcomes were assessed via changes from baseline Knee injury and Osteoarthritis Outcome Score (KOOS), International Knee Documentation Committee score, and modified Lysholm assessments at 1- and 5-year follow-up. Structural repair was evaluated using MOCART (magnetic resonance observation of cartilage repair tissue) score. Treatment-related adverse events were assessed up to 5 years for all patients. The overall KOOS at 12 months was assessed for superiority versus baseline in a 1-sample, 2-sided t test.

Results:

A total of 73 patients were treated: 24 in the low-dose group, 25 in the medium-dose group, and 24 in the high-dose group. The overall KOOS improved from 57.0 ± 15.2 at baseline to 73.4 ± 17.3 at 1-year follow-up (P < .0001) and 76.9 ± 19.3 at 5-year follow-up (P < .0001), independent of the applied dose. The different defect locations (patella, trochlea, and weightbearing part of the femoral condyles; P = .2216) and defect sizes (P = .8706) showed comparable clinical improvement. No differences between the various doses were observed. The overall treatment failure rate until 5 years was 4%. Most treatment-related adverse events occurred within the first 12 months after implantation, with the most frequent adverse reactions being joint effusion (n = 71), arthralgia (n = 14), and joint swelling (n = 9).

Conclusion:

ACI using spheroids was safe and effective for defect sizes up to 10 cm² and showed maintenance of efficacy up to 5 years for all 3 doses that were investigated.

Registration:

NCT01225575 (ClinicalTrials.gov identifier); 2009-016816-20 (EudraCT number).

Good clinical outcomes after patellar cartilage repair with no evidence for inferior results in complex cases with the need for additional patellofemoral realignment procedures: a systematic review

PURPOSE

Focal, patellar cartilage defects are a challenging problem as most cases have an underlying multifactorial pathogenesis. This systematic review of current literature analysed clinical results after regenerative cartilage repair of the patella with a special focus on the assessment and treatment of existing patellofemoral malalignment.

METHODS

A systematic review was conducted to identify articles reporting clinical results after cartilage regenerative surgeries of the patella using the PubMed and Scopus database. The extracted data included patient-reported outcome measures (PROMS) and whether cartilage repair was performed alone or in combination with concomitant surgeries of underlying patellofemoral co-pathologies. In cases of isolated cartilage repair, specific exclusion criteria regarding underlying co-pathologies were screened. In cases of concomitant surgeries, the type of surgeries and their specific indications were extracted.

RESULTS

A total of 35 original articles were included out of which 27 (77%) were cohort studies with level IV evidence. The most frequently used technique for cartilage restoration of the patella was autologous chondrocyte implantation (ACI). Results after isolated cartilage repair alone were reported by 15 (43%) studies. Of those studies, 9 (60%) excluded patients with underlying patellofemoral malalignment a priori and 6 (40%) did not analyse underlying co-pathologies at all. Among the studies including combined surgeries, the most frequently reported concomitant procedures were release of the lateral retinaculum, reconstruction of the medial patellofemoral ligament (MPFL), and osteotomy of the tibial tubercle. In summary, these studies showed lower preoperative PROMS but similar final PROMS in comparison with the studies reporting on isolated cartilage repair. The most frequently used PROMS were the IKDC-, Lysholm- and the Modified Cincinnati Score.

CONCLUSION

This comprehensive literature review demonstrated good clinical outcomes after patellar cartilage repair with no evidence of minor results even in complex cases with the need for additional patellofemoral realignment procedures. However, a meaningful statistical comparison between isolated patellar cartilage repair and combined co-procedures is not possible due to very heterogeneous patient cohorts and a lack of analysis of specific subgroups in recent literature.

LEVEL OF EVIDENCE

Level IV.

Short-term radiological results after spheroid-based autologous chondrocyte implantation in the knee are independent of defect localisation

BACKGROUND

Lesions of articular cartilage represent a crucial risk factor for the early development of osteoarthritis. Autologous chondrocyte implantation (ACI) is a well-established procedure in therapy of those lesions in the knee. The aim of the presented study is to detect differences in short-term radiological outcome depending on defect localization (femoral condyle vs. retropatellar) after spheroid-based ACI.

OBJECTIVE

This study aimed to demonstrate that radiological outcome after spheroid-based ACI in the knee is independent of defect localization.

METHODS

MRI-scans after retropatellar ACI and ACI of the medial/lateral femoral condyle, with a preoperative Outerbridge grade of III or IV were evaluated regarding MOCART 2.0.

RESULTS

The mean defect-size was 5.0 ± 1.8 cm2, with a minimum size of 2 cm2 and a maximum size of 9 cm2. Scans were performed 7.7 months (± 3.1 months) postoperatively. The mean MOCART 2.0 score was 78.5 ± 15.6. No statistically significant influence neither of the localization (p= 0.159), the gender (p= 0.124) nor defect size (< 5 cm2 vs. ⩾ 5 cm2; p= 0.201) could be observed.

CONCLUSIONS

The presented data demonstrate good to excellent radiological short-term results after spheroid-based ACI. Data indicates, that at least radiological results are independent of gender, defect-size and defect-localization.

Role of Matrix-Associated Autologous Chondrocyte Implantation with Spheroids in the Treatment of Large Chondral Defects in the Knee: A Systematic Review

Autologous chondrocyte implantation (ACI) is a cell therapy for the treatment of focal cartilage defects. The ACI product that is currently approved for use in the European Union (EU) consists of spheroids of autologous matrix-associated chondrocytes. These spheroids are spherical aggregates of ex vivo expanded human autologous chondrocytes and their self-synthesized extracellular matrix. The aim is to provide an overview of the preclinical and nonclinical studies that have been performed to ensure reproducible quality, safety, and efficacy of the cell therapy, and to evaluate the clinical data on ACI with spheroids. A systematic review was performed to include all English publications on self-aggregated spheroids of chondrocytes cultured in autologous serum without other supplements. A total of 20 publications were included, 7 pre- and nonclinical and 13 clinical research publications. The pre- and nonclinical research publications describe the development from concept to in vivo efficacy and quality- and safety-related aspects such as biodistribution, tumorigenicity, genetic stability, and potency. The evaluation of clinical research shows short- to mid-term safety and efficacy for the ACI with spheroid-based treatment of cartilage defects in both randomized clinical trials with selected patients, as well as in routine treatment providing real-world data in more complex patients.

Effect of the defect localization and size on the success of third-generation autologous chondrocyte implantation in the knee joint

INTRODUCTION

Femoral and patellar cartilage defects with a defect size > 2.5 cm² are a potential indication for an autologous chondrocyte implantation (ACI). However, the influence of the localization and the absolute and relative defect size on the clinical outcome has not yet been determined. The purpose of this study is to analyze the influence of the localization and the absolute and relative defect size on the clinical outcome after third-generation autologous chondrocyte implantation.

METHODS

A total of 50 patients with cartilage defects of the knee were treated with third-generation autologous chondrocyte implantation (Novocart® 3D). A match paired analysis was performed of 25 treated femoral and 25 treated patella defects with a follow-up of three years. MRI data was used to do the manual segmentation of the cartilage layer throughout the knee joint. The defect size was determined by taking the defect size measured in the MRI in relation to the whole cartilage area. The clinical outcome was measured by the IKDC score and VAS pre-operatively and after six, 12, 24, and 36 months post-operatively.

RESULTS

IKDC and VAS scores showed a significant improvement from the baseline in both groups. Femoral cartilage defects showed significantly superior clinical results in the analyzed scores compared to patellar defects. The femoral group improved IKDC from 33.9 (SD 18.1) pre-operatively to 71.5 (SD 17.4) after three years and the VAS from 6.9 (SD 2.9) pre-operatively to 2.4 (SD 2.5) after three years. In the patellar group, IKDC improved from 36.1 (SD 12.6) pre-operatively to 54.7 (SD 20.3) after three years and the VAS improved from 6.7 (SD 2.8) pre-operatively to 3.4 (SD 2.) after three years. Regarding the defect size, results showed that the same absolute defect size at med FC (4.8, range 2-15) and patella (4.6, range 2-12) has a significantly different share of the total cartilaginous size of the joint compartment (med FC: 6.7, range 1.2-13.9; pat: 18.9, range 4.0-47.0). However, there was no significant influence of the relative defect size on the clinical outcome in either patellar or femoral localization.

CONCLUSION

Third-generation autologous chondrocyte implantation in ACI-treated femoral cartilage defects leads to a superior clinical outcome in a follow-up of three years compared with patellar defects. No significant influence of the defect size was found in either femoral or patellar cartilage defects.

Effect of the defect localization and size on the success of third-generation autologous chondrocyte implantation in the knee joint

INTRODUCTION

Femoral and patellar cartilage defects with a defect size > 2.5 cm² are a potential indication for an autologous chondrocyte implantation (ACI). However, the influence of the localization and the absolute and relative defect size on the clinical outcome has not yet been determined. The purpose of this study is to analyze the influence of the localization and the absolute and relative defect size on the clinical outcome after third-generation autologous chondrocyte implantation.

METHODS

A total of 50 patients with cartilage defects of the knee were treated with third-generation autologous chondrocyte implantation (Novocart® 3D). A match paired analysis was performed of 25 treated femoral and 25 treated patella defects with a follow-up of three years. MRI data was used to do the manual segmentation of the cartilage layer throughout the knee joint. The defect size was determined by taking the defect size measured in the MRI in relation to the whole cartilage area. The clinical outcome was measured by the IKDC score and VAS pre-operatively and after six, 12, 24, and 36 months post-operatively.

RESULTS

IKDC and VAS scores showed a significant improvement from the baseline in both groups. Femoral cartilage defects showed significantly superior clinical results in the analyzed scores compared to patellar defects. The femoral group improved IKDC from 33.9 (SD 18.1) pre-operatively to 71.5 (SD 17.4) after three years and the VAS from 6.9 (SD 2.9) pre-operatively to 2.4 (SD 2.5) after three years. In the patellar group, IKDC improved from 36.1 (SD 12.6) pre-operatively to 54.7 (SD 20.3) after three years and the VAS improved from 6.7 (SD 2.8) pre-operatively to 3.4 (SD 2.) after three years. Regarding the defect size, results showed that the same absolute defect size at med FC (4.8, range 2-15) and patella (4.6, range 2-12) has a significantly different share of the total cartilaginous size of the joint compartment (med FC: 6.7, range 1.2-13.9; pat: 18.9, range 4.0-47.0). However, there was no significant influence of the relative defect size on the clinical outcome in either patellar or femoral localization.

CONCLUSION

Third-generation autologous chondrocyte implantation in ACI-treated femoral cartilage defects leads to a superior clinical outcome in a follow-up of three years compared with patellar defects. No significant influence of the defect size was found in either femoral or patellar cartilage defects.