Limin Liu

Infection is the most common complication of osteoporotic fractures, often characterized by bacterial resistance and intracellular infection, posing a major challenge in the treatment of osteoporotic fractures. Here, we developed a multifunctional biomimetic Trojan horse nanosystem based on hydroxyapatite nanotubes (NT‐HA) for microenvironment remodeling. The NT‐HA exhibits a dual‐stage antimicrobial peptide (AMP) delivery strategy, in which surface‐adsorbed AMPs are rapidly released to eliminate extracellular bacteria, while NT‐HA is internalized via endocytosis to release encapsulated AMPs for efficient intracellular bacterial clearance. After releasing AMPs, the NT‐HA can regulate the PI3K‐AKT signaling cascade, promoting the directed osteogenic differentiation of osteoporotic bone marrow mesenchymal stem cells (OBMSCs). In the repair of infected osteoporotic bone defects in vivo, this Trojan horse nanosystem not only enhances bone regeneration by eliminating cellular infections and inducing OBMSCs osteogenesis but also reduces peri‐implant bone loss and strengthens bone strength, ultimately remodeling the regenerative microenvironment to achieve optimal bone defect repair and functional reconstruction.

Adjacent segment disease (ASD) is a frequent complication following spinal fusion surgery, particularly prevalent in elderly patients. The nutritional status of elderly patients is also closely related to postoperative outcomes. However, the relationship between nutritional status and the incidence of ASD after spinal surgery remains unknown. This research uniquely evaluates the predictive value of the Geriatric Nutritional Risk Index (GNRI) concerning the development of postoperative ASD in elderly individuals (aged 65 years and above) who underwent transforaminal lumbar interbody fusion (TLIF) for degenerative lumbar disorders. A retrospective study was conducted to assess the outcomes of TLIF in elderly patients with lumbar degenerative disease between 2016 and 2022. Based on the presence or absence of ASD, patients were categorized into the ASD group and the non-ASD group. Demographic, radiographic, and laboratory data were collected. The GNRI was calculated using the baseline serum albumin level and body weight. Univariate and multivariate logistic regression were employed to identify potential preoperative risk factors for ASD. Additionally, a receiver operating characteristic (ROC) curve was utilized to determine the optimal cutoff values of risk factors for predicting ASD. A total of 216 patients (aged 69.67 ± 3.46 years) were included in the analysis, of whom 39(18.1%) developed ASD. The mean GNRI was 102.91 ± 7.42 in the non-ASD group and 95.01 ± 7.95 in the ASD group (p๤0.001). On multivariate logistic regression, GNRI was an independent factor in the prediction of ASD following TLIF, and susceptibility to ASD increases significantly with low GNRI (OR 0.88; 95%CI: 0.81 ~ 0.97; p = 0.007). On the receiver operating characteristic curve, the area under the curve (AUC) for GNRI was 0.802 (95%CI: 0.718 ~ 0.887), significantly higher than that of Alb (AUC = 0.675, 95%CI: 0.582 ~ 0.767, p = 0.007) and BMI (AUC = 0.616, 95%CI: 0.521 ~ 0.710, p = 0.022). The cutoff value for GNRI according to the Youden index was 97.05 (sensitivity: 77.4%, specificity: 69.2%). Our study revealed a significant correlation between lower GNRI scores and the occurrence of ASD following TLIF. Evaluating GNRI prior to TLIF could serve as an effective strategy for predicting ASD risk in elderly patients with degenerative lumbar conditions, thereby facilitating more informed clinical decision-making.

Study Design.: Prospective observational cohort study. Objective.: To prospectively evaluate the utility of traditional and single-level vertebral bone quality (VBQ) scores for preoperative bone mineral density (BMD) assessment in patients undergoing lumbar fusion surgery, and to validate their diagnostic performance against dual-energy x-ray absorptiometry (DEXA) and quantitative computed tomography (QCT). Summary of Background Data.: Magnetic resonance imaging (MRI)-based VBQ score has been proposed to assess BMD, but prospective evidence comparing different vertebral levels is lacking. Materials and Methods.: Participants were classified into normal, osteopenia, and osteoporosis groups based on DEXA T -score and QCT-vBMD. Intergroup differences were analyzed, with post hoc corrections for multiple comparisons. Correlations between VBQ scores and BMD were evaluated, while receiver operating characteristic (ROC) analysis assessed their diagnostic performance. Linear and logistic regression models were further applied to examine the independent association between VBQ scores and osteoporosis. Results.: Among 198 patients (58.9±11.8 yr; 56.6% female), groups differed significantly in age and sex ( P T -score and QCT-vBMD at most vertebral levels, with stronger correlations observed for QCT ( r =−0.412 to −0.563). ROC analysis confirmed that VBQ scores effectively differentiated normal, osteopenia, and osteoporosis. Multivariable regression identified higher L1-L4 VBQ scores as independent predictors of lower BMD (DEXA: β=–0.412; QCT: β=–0.469) and increased osteoporosis risk (DEXA: OR=3.201, 95% CI=1.056–9.704; QCT: OR=2.741, 95% CI=1.061–7.080). Conclusion.: This prospective study demonstrated that the L1–L4 VBQ score exhibited superior stability and generalizability compared with single-level measurements, supporting its potential use as a practical surrogate marker for opportunistic BMD screening in patients undergoing spinal surgery. Specific single-level scores, such as those at L1, L2, and S1, may still provide supplementary diagnostic value in detecting early bone quality alterations. Level of Evidence.: Level 2.

To investigate the influence of the preoperative compensatory curve on the postoperative curve progression in congenital scoliosis (CS) patients following hemivertebra (HV) resection and short fusion and to analyze the risk factors for postoperative curve progress. This study retrospectively reviewed a consecutive cohort of CS patients who underwent HV resection and short fusion with a minimum follow-up of 2 years. General demographic information, as well as preoperative, postoperative, and latest follow-up radiographic data, were collected. The fusion segment (FS) referred to the number of vertebrae within the anchoring range of the most cranial and caudal pedicle screws. The main curve segment (MCS) was defined as the number of vertebrae included in the main curve. Patients were divided into two groups based on the presence or absence of compensatory curves preoperatively: the compensatory curve group (Group C) and the non-compensatory curve group (Group NC). Furthermore, patients were categorized into progression (Group P) and non-progression (Group NP) groups based on the evolution of the coronal curve after surgery. Logistic regression analysis was employed to identify risk factors for curve progression, and receiver operating characteristic (ROC) curves were constructed to evaluate the predictive value of these risk factors. A total of 205 patients were included in this study, with 58 classified into Group C and 147 into Group NC. The incidence of postoperative progression of the coronal curve was notably higher in Group C compared to Group NC, with incidences of 29.3% and 12.9%, respectively (p = 0.005). Multivariate logistic regression analysis revealed that a lower FS/MCS ratio, a larger postoperative tilt of the UIV, and a larger postoperative tilt of the LIV were all independent risk factors contributing to the progression of the curve following surgery. Receiver operator characteristic (ROC) curves showed superior predictive value of FS/MCS for postoperative curve progression (AUC: 0.793; 95%CI: 0.675 ~ 0.912; p < 0.001). The optimal cut-off value for FS/MCS was 0.915 using the Youden index. The presence of the compensatory curve appeared to increase the likelihood of postoperative curve progression in CS patients undergoing posterior HV resection and short fusion. Key risk factors for this progression include a lower FS/MCS ratio and more pronounced tilting of the postoperative UIV and LIV. We recommended proper alignment of FS with MCS, as well as horizontalization of both the UIV and LIV.

Purpose This study aimed to comprehensively evaluate the association between paraspinal muscle fat infiltration (FI) and three MRI-based vertebral bone quality indicators—Vertebral Bone Quality (VBQ), Modified VBQ (MVBQ), and Endplate Bone Quality (EBQ)—in patients with lumbar degenerative diseases (LDD), and to compare their diagnostic and prognostic implications. Methods A retrospective analysis included 261 patients undergoing transforaminal lumbar interbody fusion (TLIF) for LDD. Paraspinal muscle parameters—total cross-sectional area (TCSA), functional CSA (FCSA), relative FCSA (rFCSA), and fat infiltration rate (FIR)—were obtained from preoperative MRI. VBQ, MVBQ, and EBQ scores were also calculated. Patients were stratified into high and low FI groups based on FIR quartiles. Correlation and multivariable regression analyses were performed, and diagnostic performance was assessed using Receiver Operating Characteristic (ROC) curves, Clinical outcomes (Oswestry Disability Index (ODI), Visual Analogue Scale (VAS)) were followed up for 2 years. Results Patients with high FI exhibited significantly elevated VBQ (3.41 vs. 3.01, p < 0.001), MVBQ (3.47 vs. 2.91, p < 0.001), and EBQ (3.31 vs. 2.97, p = 0.001) scores compared to the normal FI group. FIR correlated positively with all bone quality indices, with the strongest association for MVBQ (r = 0.432, p < 0.001). MVBQ demonstrated superior diagnostic performance (AUC = 0.70) compared to VBQ (AUC = 0.64) and EBQ (AUC = 0.53). At 2-year follow-up, high FI patients had worse ODI scores (11.61 vs. 10.57, p = 0.031), though no differences in VAS were observed. Conclusion Our study established a significant association between paraspinal muscles FI and the bone quality of various regions of the vertebrae, as well as prognosis undergoing surgery for LDD patients. MVBQ may serve as a reliable and practical preoperative marker for musculoskeletal degeneration in patients with LDD, guiding individualized risk stratification and rehabilitation planning.