RESUMEN
The treatment of various large bone defects has remained a challenge for orthopedic surgeons for a long time. Recent research indicates that curculigoside (CUR) extracted from the curculigo plant exerts a positive influence on bone formation, contributing to fracture healing. In this study, we employed emulsification/solvent evaporation techniques to successfully fabricate poly(ε-caprolactone) nanoparticles loaded with curculigoside (CUR@PM). Subsequently, using three-dimensional (3D) printing technology, we successfully developed a bioinspired composite scaffold named HA/GEL/SA/CUR@PM (HGSC), chemically cross-linked with calcium chloride, to ensure scaffold stability. Further characterization of the scaffold's physical and chemical properties revealed uniform pore size, good hydrophilicity, and appropriate mechanical properties while achieving sustained drug release for up to 12 days. In vitro experiments demonstrated the nontoxicity, good biocompatibility, and cell proliferative properties of HGSC. Through alkaline phosphatase (ALP) staining, Alizarin Red S (ARS) staining, cell migration assays, tube formation assays, and detection of angiogenic and osteogenic gene proteins, we confirmed the HGSC composite scaffold's significant angiogenic and osteoinductive capabilities. Eight weeks postimplantation in rat cranial defects, Micro-computed tomography (CT) and histological observations revealed pronounced angiogenesis and new bone growth in areas treated with the HGSC composite scaffold. These findings underscore the scaffold's exceptional angiogenic and osteogenic properties, providing a solid theoretical basis for clinical bone repair and demonstrating its potential in promoting vascularization and bone regeneration.
RESUMEN
OBJECTIVE: The purpose of this study was to investigate the influence of sagittal alignment according to age-adjusted pelvic incidence minus lumbar lordosis (PI-LL) and lordosis distribution index (LDI) on the occurrence of adjacent-segment disease (ASD) after lumbar fusion surgery. METHODS: This study retrospectively reviewed 234 consecutive patients with lumbar degenerative diseases who underwent 1- or 2-level lumbar fusion surgery. Demographic and radiographic (preoperative and 3-month postoperative) data were collected and compared between ASD and non-ASD groups. Binary logistic regression analysis was performed to evaluate adjusted associations between potential variables and ASD development. A subanalysis was further conducted to assess their relationships in the range of different PI values. RESULTS: With a mean follow-up duration of 70.6 months (range 60-121 months), 118 patients (50.4%) were diagnosed as having cranial radiological ASD. Univariate analyses showed that older age, 2-level fusion, worse preoperative pelvic tilt and LL, lower pre- and postoperative LDI, and more improvement in sagittal vertical axis were significantly correlated with the occurrence of ASD. No significant differences in the PI-LL and age-adjusted PI-LL (offset) were detected between ASD and non-ASD groups. Multivariate analysis identified postoperative LDI (OR 0.971, 95% CI 0.953-0.989, p = 0.002); 2-level fusion (OR 3.477, 95% CI 1.964-6.157, p < 0.001); and improvement of sagittal vertical axis (OR 0.992, 95% CI 0.985-0.998, p = 0.039) as the independent variables for predicting the occurrence of ASD. When stratified by PI, LDI was identified as an independent risk factor in the groups with low and average PI. Lower segmental lordosis (OR 0.841, 95% CI 0.742-0.954, p = 0.007) could significantly increase the incidence of ASD in the patients with high LDI. CONCLUSIONS: Age-adjusted PI-LL may have limited ability to predict the development of ASD. LDI could exert an important effect on diagnosing the occurrence of ASD in the cases with low and average PI, but segmental lordosis was a more significant risk factor than LDI in individuals with high PI.