W. Yan (Beijing, CN)
Peking University Third Hospital Department of Sports MedicinePresenter Of 2 Presentations
16.2.9 - An injectable hydrogel scaffold with Kartogenin-encapsulated nanoparticles for porcine cartilage regeneration – a six months follow-up
Abstract
Purpose
Based on our previous study, the utilization of an ultraviolet (UV) light photo-cross-linkable Hyaluronic acid (HA) hydrogel integrated with Kartogenin-encapsulated nanoparticles obtained good reconstruction of osteochondral defects in rabbit model. To further evaluate the safety and efficacy of this technique, the focal cartilage defects with critical size of a porcine model was used. Moreover, the defects with different sizes were created to assess which defect size it is suitable for repairing in future clinical applications.
Methods and Materials
24 skeletally mature minipigs were randomly divided into three groups, including m-HA hydrogel with Kartogenin-encapsulated nanoparticles treated (m-HA + KGN group), m-HA hydrogel treated (m-HA group) and untreated (Blank group). Focal defects were created in medial femoral condyle in both knees. Full-thickness (FT) cartilage defects (6.5 mm in diameter, 8.5 mm in diameter) and osteochondral defects (6.5 mm and 8.5 mm in diameter, 5mm in depth) were included. At 6 months, all minipigs were sacrificed for assessment of macroscopic appearance, MRI, micro-computed tomography (µCT), histology staining and the evaluation of elastic modulus, hardness and COL2, glycosaminoglycan (GAG) contents of the regenerated tissue.
Results
m-HA + KGN group had improved gross healing and histological scores, compared to m-HA and Blank group. The improved-quality repaired cartilage demonstrated by MRI and better subchondral bone reconstruction assessed by µCT were also observed in m-HA + KGN group. The m-HA + KGN group showed hyaline-like cartilage exhibited by histological staining in terms of extracellular matrix, cartilage lacuna and COL2. The mechanical properties were also improved in m-HA + KGN group, but remained inferior to normal cartilage, while COL2 and GAG contents remained same condition.
Conclusion
The HA hydrogel integrated with Kartogenin-encapsulated nanoparticles appeared to improve cartilage healing in critical sized defects in the minipig model evaluated for 6 months, with better cartilage healing in Full-thickness cartilage defects compared to osteochondral defects.
18.1.2 - Femoral and Tibial Torsion Measurements Based on EOS Imaging Compared to 3D CT Reconstruction Measurements
Abstract
Purpose
The purpose of this study was (1) to investigate whether there was good agreement between EOS imaging based and three-dimensional (3D) CT reconstruction based technique in measuring femoral, tibial and femorotibial torsion; (2) to verify the reliability and reproducibility of EOS Imaging in measuring femoral, tibial and femorotibial torsion.
Methods and Materials
A prospective study was conducted including 18 adult volunteers (36 lower extremities) (24±2 years old). Femoral and tibial torsion were measured by both EOS imaging and three-dimensional CT reconstruction. Bland-Altman plots were performed to evaluate the difference between femoral and tibial torsion measurements obtained by these two methods. The intraclass correlation coefficient was used to evaluate intrareader agreement.
Results
The mean difference between the two methods was 3°(range, –9°to 4°) for femoral torsion, 0°(range, –6°to 6°) for tibial torsion and 0°(range, –4° to 5°) for femorotibial torsion. No statistically significant difference between the measurements of the two methods was detected by Bland-Altman plots. With the exception of one measurement of femoral torsion, one measurement of tibial torsion and one measurement of femorotibial torsion, all EOS imaging measurements were within the 95% limits of agreement (the mean ± 1.96 SD). Intrareader agreement was statistically significant (P<0.001) for all measurements, with high intraclass correlation coefficients. For EOS imaging, the intraclass correlation coefficient (ICC) was 0.92 for the femoral measurement, 0.92 for the tibial measurement and 0.918 for the femorotibial measurement; the corresponding values for CT were 0.95, 0.927 and 0.889.
Conclusion
There was good agreement between EOS imaging based and 3D CT reconstruction based technique in measuring femoral, tibial and femorotibial torsion; and good reliability and reproducibility of EOS Imaging in measuring femoral, tibial and femorotibial torsion was also verified.