Effect of a Simvastatin-Impregnated Chitosan Scaffold on Cell Growth and Osteoblastic Differentiation

This study aims to evaluate the effect of chitosan (CS) scaffold, alone, and the potential synergistic effect when impregnated with simvastatin (SIM), on immortalized human bone-marrow mesenchymal stem cells (hbMMSCs) compared to CollaCote (CL). CS scaffolds were fabricated and seeded with immortalized hBMMSCs. Samples were divided into control groups (negative with no added material and positive with CL added) and four experimental groups: CS alone, CS/SIM 0.01, 0.03, and 0.05 mg, respectively. Cell viability, osteoblastic differentiation and calcium deposition were investigated via AlamarBlue, alkaline phosphate activity assays and alizarin red S staining at 1 and 14 days, respectively. At day one, no significant difference was noted between the groups regarding cell viability. However, all CS/SIM groups showed significant cutback at day 14 in cell proliferation compared to CS alone and CL groups (p < 0.001). All groups supported osteoblastic differentiation with no significant difference. Alkaline phosphate activity increased in both time periods in the CS/SIM 0.05 mg group compared to the other SIM groups, with no significant difference among the experimental groups. Chitosan scaffold is a bioactive compatible material capable of regenerative potential of hBMMSCs and a promising material to be used for perforation repair.

Treatment of Patellofemoral Chondral Lesions Using Microfractures Associated with a Chitosan Scaffold: Mid-Term Clinical and Radiological Results

Objective To assess the clinical and radiological results of patellofemoral osteochondral lesions treated with microfractures associated with a chitosan scaffold. Design A retrospective observational analytical study was performed. Fifteen patients with full-thickness patellofemoral osteochondral lesions were included. Quantity and quality of the reparation cartilage was assessed with the MOCART 2.0 score on a postoperative magnetic resonance imaging (MRI), and clinical outcomes were evaluated with pre- and postoperative Kujala score tests. Shapiro-Wilk test for normality was applied as well as Wilcoxon’s signed rank test and Kruskal-Wallis H test for clinical scores within subjects and patella versus trochlea subgroups comparisons. Analysis of variance test was used for imaging subgroups comparison, with P < 0.05 defined as statistical significance. Results Mean follow-up was 33.36 months (range 24-60 months). Postoperative Kujala scores improved an average of 19 points compared with the preoperative state (SE = 17.6; P < 0.001). No statistical difference was found through the clinical location assessment ( P = 0.756), as well as the cartilage imaging assessment ( P = 0.756). The mean MOCART 2.0 scale was 67.67 (range 50-85). Conclusions Treating full-thickness patellofemoral osteochondral lesions with microfractures associated with a chitosan scaffold proved to be effective regarding defect filling and symptomatic improvement.