Microfractures Versus a Porcine derived Collagen-Augmented Chondrogenesis Technique for Treating Knee Cartilage Defects: A Multicenter Randomized Controlled Trial

Abstract Purpose The purpose of this study was to evaluate the clinical efficacy and safety of treating patients with a cartilage defect of the knee with microfractures and porcine-derived collagen-augmented chondrogenesis technique (C-ACT). Methods One hundred participants were randomly assigned to the control group (n = 48, microfracture) or the investigational group (n = 52, C-ACT). Clinical and magnetic resonance imaging (MRI) outcomes were assessed 12 and 24 months postoperatively for efficacy and adverse events. Magnetic Resonance Observation of Cartilage Repair Tissue (MOCART) assessment was used to analyze cartilage tissue repair. Magnetic resonance imaging (MRI) outcomes for 50% defect filling and Repaired Tissue/Reference Cartilage (RT/RC) ratio were quantified using T2 mapping. Clinical outcomes were assessed using the visual analogue scale (VAS)–pain, VAS–20% improvement, minimal clinically important difference (MCID), patient acceptable symptom state for Knee Injury and Osteoarthritis Outcome Score (KOOS) and the International Knee Documentation Committee score. Results MOCART scores in the investigation group showed improved defect repair and filling (P = 0.0201), integration with the border zone (P = 0.0062) and effusion (P = 0.0079). MRI outcomes showed that the odds ratio (OR) for ≥ 50% defect filling at 12 months was statistically higher in the investigation group (OR = 3.984, P = 0.0377). Moreover, the likelihood of the RT/RC OR becoming ≥ 1 was significantly higher (OR = 11.37, P = 0.0126) in the investigation group. At 24 months postoperatively, the odds ratio (OR) for the VAS–20% improvement rate was significantly higher in the investigational group (OR=2.808, P=0.047). Twenty-three patients (52.3%) in the control group and 35 (77.8%) in the investigation group demonstrated over the MCID of KOOS pain from baseline to 1-year postoperatively with a significant difference between groups (P = 0.0116). Conclusion In this multicenter randomized trial, the addition of C-ACT resulted in better filling of cartilage defect of the knee joint.