Observational studies have demonstrated associations between plasma metabolites and sarcopenia/aging. This study aimed to investigate the genetically predicted associations between plasma metabolites and sarcopenia/aging traits and to discover the regulating genes. A Mendelian randomization (MR) study was performed using metabolomic data obtained from the Canadian Longitudinal Study on Aging cohort. Data of sarcopenia/aging traits were obtained from genome-wide association studies for frailty index, telomere length, left- and right-hand grip strength, adjusted appendicular lean mass, anterior and posterior thigh muscle fat infiltration, total thigh muscle volume z-score and usual walking pace. Sensitivity analyses, reverse MR and Bayesian colocalization were employed to validate the genetically predicted associations. Replication analyses were performed in the metabolic syndrome in men cohort. The MR analysis identified 18 per-trait and two across-trait significant associations between plasma metabolites/metabolite ratios and sarcopenia/aging traits, five of which were successfully replicated in external validation. Using functional mapping and annotation analysis, protein tyrosine phosphatase receptor type D (PTPRD) was mapped to the genomic risk loci of multiple significant metabolites/metabolite ratios and was transcriptionally upregulated in the muscle of the (pre-)frail elderly. Single-cell analysis further showed that PTPRD was mainly expressed in adipogenic MME+ fibro-adipogenic progenitors in the skeletal muscle tissue, which could cause elevated levels of circulating lipid metabolites and fat infiltration in the skeletal muscle, triggering sarcopenia and aging of the muscle. In conclusion, this study revealed the role of PTPRD in regulating the genetically predicted associations between plasma metabolites/metabolite ratios and sarcopenia/aging traits, thereby contributing to the improved risk assessment and prevention strategies for aging and sarcopenia, meriting further investigation.

Ferroptosis contributes to intervertebral disc degeneration (IVDD), yet its upstream regulatory mechanisms in nucleus pulposus cells (NPCs) remain unclear. Here, we identify a novel UCHL3-HMGB1-NCOA4 signaling axis that drives NPC ferroptosis. Transcriptomic and clinical analyses reveal that UCHL3 is upregulated in degenerative discs, with its expression correlating positively with both IVDD severity and ferroptosis markers. Mechanistically, UCHL3 deubiquitinates and stabilizes HMGB1 by cleaving Lys48-linked polyubiquitin chains, thereby promoting the accumulation of cytoplasmic HMGB1. This stabilized HMGB1 activates NCOA4-mediated ferritinophagy, initiating ferroptosis. Silencing UCHL3 or NCOA4 mitigates these effects. Furthermore, a polydopamine-based nanoplatform (PDA@si-UCHL3) achieves dual therapeutic action, silencing UCHL3 while scavenging ROS and chelating iron, which effectively inhibits ferroptosis and alleviates IVDD in rats. These findings establish UCHL3 as a pivotal regulator of NPC ferroptosis and highlight PDA@si-UCHL3 as a promising therapeutic strategy for IVDD.Abbreviations: AAV: adeno-associated virus; CCK-8: cell counting kit-8; Co-IP: co-immunoprecipitation; DUBs: deubiquitinating enzymes; ECM: extracellular matrix; GPX4: glutathione peroxidase 4; GSH: glutathione; HE: hematoxylin and eosin; HMGB1: high mobility group box 1; IF: immunofluorescence; IHC: immunohistochemistry; IP/MS: immunoprecipitation mass spectrometry; IVDD: intervertebral disc degeneration; IVDs: intervertebral discs; MRI: magnetic resonance imaging; NCOA4: nuclear receptor coactivator 4; NP: nucleus pulposus; NPCs: nucleus pulposus cells; PDA: polydopamine; PG: Pfirrmann grading; ROS: reactive oxygen species; siRNA: small interfering RNAs; SO-FG: Safranin O-Fast Green; TBHP: tert-butyl hydroperoxide; TEM: transmission electron microscope; UCHL3: ubiquitin C-terminal hydrolase L3; WT: wild-type.

This prospective multicenter controlled cohort study evaluated whether structured supervised early operative exposure improves educational and clinical outcomes among junior Orthopedic residents. The goal of this protocol is to describe a structured, competency-based approach for implementing supervised early operative exposure in orthopedic residency training and evaluating its educational and clinical impact. Ninety-six first and second-year residents across three tertiary teaching hospitals were allocated to early exposure or traditional training and followed for 12 months. Residents receiving early supervised exposure demonstratedprocedures andincrease in surgical confidence (mean change 2.4 points; 95% CI 1.9-2.9; p < 0.001), reduced operative duration by approximately 20% in common procedures, and maintained low complication rates within accepted clinical benchmarks. Patient satisfaction and functional recovery outcomes remained high and improved in parallel with resident development. Surgical confidence showed a strong positive correlation with supervisor-rated technical skill (r = 0.81). These findings indicate that competency-based supervised early operative participation enhances resident performance and patient outcomes without compromising safety, supporting its integration into Orthopedic residency training.

STUDY DESIGN:A retrospective study. OBJECTIVE:To characterize subtype-specific gait patterns and neuromuscular adaptations in DSD using integrated 3D motion capture and surface electromyography (sEMG). BACKGROUND:Degenerative spinal diseases (DSD), including lumbar spinal stenosis (LSS), adult spinal deformity (ASD), and cervical spondylotic myelopathy (CSM), commonly impair gait in elderly patients. MATERIALS AND METHODS:In this retrospective cross-sectional study, 148 participants (31 ASD, 40 LSS, 35 CSM, 42 healthy controls) underwent gait analysis with a BTS motion capture system and sEMG assessment of erector spinae, multifidus, gluteus maximus, and rectus abdominis muscles. Spatiotemporal parameters, root mean square maximum (RMSmax) and median frequencies (MF) were compared across stance and swing phases. Nonparametric statistical analyses were performed with significance at P<0.05. RESULTS:The study included 106 patients with degenerative spinal diseases and 42 healthy elderly controls. A three-dimensional motion capture system and surface electromyography were used to synchronously analyze complete gait cycle parameters. The results showed that compared to the HC group, all three patient groups exhibited significantly reduced gait speed, lower step frequency, prolonged double-support time, increased step width, and increased asymmetry in lower limb gait parameters (P <0.001). sEMG analysis revealed that the ASD and LSS groups had increased RMSmax values and decreased MF (P <0.001). The asymmetry indices of bilateral muscles in all three patient groups were higher than those in the HC group (P <0.001), indicating compromised neuromuscular control related to disease-specific pathology. CONCLUSION:The study systematically revealed abnormal gait parameters and distinct activation patterns of core muscles in patients with degenerative spinal conditions, along with their underlying causes. Patients in the DSD group exhibited poorer bilateral lower limb gait stability and walking speed, with different muscle activation patterns due to varying causes. LEVEL OF EVIDENCE:Level IV.

PURPOSE:Humans are the only bipedal vertebrates, and the links between the lower-extremity muscles and spinal disorders have been highlighted. However, the exact relationships between them are not fully understood. This study aimed to elucidate the genetically predicted associations between lower-extremity muscle traits and spinal diseases using Mendelian randomization (MR) analysis. METHODS:We used summary statistics from genome-wide association studies for lower-extremity muscle traits from UK Biobank, including thigh muscle volume, thigh muscle fat infiltration, usual walking pace, etc.; and 31 types of spinal diseases from the FinnGen R10 to obtain genetic instrumental variables. We examined bidirectional MR evidence for causalities using inverse-variance weighted analyses and sensitivity analyses. A multivariate MR approach was applied to investigate the direct effect between the significant associations identified by univariate MR. RESULTS:Slow walking pace was found to be a risk factor associated with 10 spinal disorders. Low back pain and sciatica were two important risk factors genetically associated with the slower walking pace. In addition, higher posterior thigh muscle fat infiltration levels could significantly increase the odds of spinal stenosis, spondylolisthesis/spondylolysis, and spondylosis. CONCLUSION:This MR study provides evidence of genetically predicted relationships between lower-extremity muscle traits and spinal diseases, and supports the development of lower-extremity exercise techniques for prevention and intervention of spinal disorders in clinical practice.

Objective:Lumbar fusion surgery serves as a crucial option for treating lumbar degenerative diseases. However, patient heterogeneity contributes to suboptimal surgical outcomes in a substantial proportion of cases. Therefore, an accurate classification may provide a powerful tool for personalized treatment and enable the identification of individuals at increased risk for unfavorable surgical outcomes (USO). The study aimed to develop a risk stratification model for USO using cluster analysis. Methods:Consecutive patients diagnosed with degenerative lumbar disease who underwent lumbar fusion between April 2019 and January 2023 were enrolled. The outcome of interest was the USO, defined as failure to achieve a minimal clinically important difference in the 36-Item Short Form Health Survey physical component summary score, with the presence of complications. Three machine learning algorithms were employed to identify risk factors associated with USO. Based on these risk factors, we conducted a data-driven clustering analysis to develop a risk stratification model. Furthermore, based on 6 machine learning models, we developed a classification classifier capable of accurately identifying the risk cluster of individual patients. Results:A total of 662 patients were enrolled for risk stratification model, 219 patients were classified as having an USO. Six features were identified as key prognostic predictors, including frailty, depression, PI-LL (pelvic incidence minus lumbar lordosis) match, surgical levels, functional independence measure, and the relative functional cross-sectional area. The K-prototypes clustering algorithm successfully identified 3 distinct clusters. Furthermore, we developed a classification classifier, in which LightGBM (light gradient boosting machine) demonstrated the highest predictive performance (area under the receiver operating characteristic curve, 0.951; 95% confidence interval [CI], 0.814-0.974; area under the precision-recall curve, 0.927; 95% CI, 0.769-0.969). Conclusion:Based on data-driven clustering analysis, we developed a risk stratification model for predicting USO following lumbar fusion surgery, which demonstrated high predictive accuracy. Further studies in larger and more diverse cohorts are warranted to validate the clinical applicability of clustering analysis in USO risk stratification.

To evaluate the predictive value of preoperative variables on postoperative outcomes, specifically by comparing the performance of clinical variables, disc radiomics, and paraspinal muscle radiomics for predicting poor disability improvement after single-level lumbar surgery. In this retrospective single-centre cohort, we included 213 adults who underwent elective L4/5 decompression and fusion for degenerative lumbar disease between January 2020 and June 2024 and had preoperative lumbar MRI and 6–12-month Oswestry Disability Index (ODI) follow-up. Poor disability improvement was defined a priori as < 20-point reduction in ODI. Sagittal and axial T2-weighted images at the index level were used for semi-automatic disc segmentation and fully automatic deep-learning-based segmentation of bilateral multifidus and erector spinae muscles. Radiomics features were extracted according to Image Biomarker Standardisation Initiative recommendations. Five L1-penalised logistic regression models with nested cross-validation were developed: (1) clinical variables (age, sex, BMI, symptom duration, baseline ODI and VAS); (2) disc radiomics; (3) muscle conventional metrics (volume, cross-sectional area, fat infiltration and Goutallier asymmetry); (4) muscle radiomics (conventional metrics plus radiomics features); and (5) combined feature-union model (clinical + disc-radiomics + muscle-radiomics). Discrimination, calibration and net benefit were assessed using area under the receiver-operating characteristic curve (AUC), Brier score and decision curve analysis. Poor disability improvement occurred in 76/213 patients (35.7

STUDY DESIGN:Retrospective Cohort Study. OBJECTIVES:To develop and externally validate an explainable machine-learning framework for perioperative risk stratification of radiographic adjacent segment degeneration (ASDeg) after short-segment lumbar fusion. SUMMARY OF BACKGROUND DATA:Radiographic ASDeg is frequently observed after lumbar fusion and may represent an early structural phenotype preceding symptomatic adjacent segment disease (ASDis) in some patients. However, existing risk assessment approaches are limited by heterogeneous risk factors, insufficient model interpretability, and limited external validation. Machine-learning methods may improve perioperative risk stratification by integrating clinical, radiographic, surgical, and functional variables. METHODS:Clinical data were retrospectively collected from two hospitals. The internal cohort included 570 patients who underwent posterior short-segment lumbar fusion for lumbar degenerative disease, and an independent cohort of 150 patients from another institution was used for external validation. The internal cohort was randomly divided into training and internal test sets at a 7:3 ratio using stratified sampling according to ASDeg status. Feature selection was performed exclusively in the training set using least absolute shrinkage and selection operator regression (LASSO), random forest-recursive feature elimination (RE-RFE), and Boruta. Five algorithms were developed and compared: logistic regression, random forest (RF), extreme gradient boosting (XGBoost), Light Gradient Boosting Machine(LightGBM), and multilayer perceptron (MLP). Model performance was evaluated using discrimination, calibration, precision-recall (P-R) analysis, and decision-curve analysis(DCA). Shapley Additive Explanations (SHAP) were used for model interpretation. RESULTS:Radiographic ASDeg occurred in 212 of 570 patients in the internal cohort. Five perioperative variables were retained for model construction: preoperative intervertebral space height (ISH), postoperative pelvic incidence-lumbar lordosis (PI-LL) mismatch, frailty, Coflex implantation, and preoperative Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)-defined lower-extremity dysfunction. Among the candidate algorithms, the RF model showed the highest discriminative performance, with an AUROC of 0.782 in the internal test set and 0.749 in the external validation cohort. SHAP analysis identified preoperative ISH as the strongest contributor to model output. CONCLUSIONS:This externally validated RF-based model provides a structured and interpretable framework for postoperative radiographic ASDeg risk stratification after short-segment lumbar fusion. By integrating clinically accessible perioperative variables, the model may support individualized imaging follow-up and provide a preliminary basis for future studies using symptomatic adjacent segment disease or revision surgery as clinically oriented endpoints.

Postoperative coronal malalignment (CM) is a prevalent complication following corrective surgery for degenerative lumbar scoliosis (DLS), particularly in lumbosacral (LS) curve-driven subtypes. This study aims to identify risk factors in this high-risk subgroup to enhance understanding of the condition and support the optimization of subtype-specific management strategies. A retrospective cohort analysis of 98 LS curve-driven DLS patients was conducted. Postoperative CM was defined as coronal balance distance (CBD) > 3 cm. A novel parameter, core offset distance (COD), was introduced to quantify the cumulative vertical displacement between the two most influential vertebral segments responsible for imbalance in the LS curve. Other coronal alignment measurements included thoracolumbar/lumbar (TL/L) curve Cobb angle, LS curve Cobb angle, upper instrumented vertebra tilt, L4 tilt, L5 tilt, pelvic obliquity, and CBD. Patient demographics and surgical parameters were also evaluated. Multivariate logistic regression was utilized to identify predictors of postoperative CM. Postoperative CM was observed in 35.7

To identify independent predictors of postoperative axial symptoms (AS) after cervical laminoplasty (CLP) and evaluate the predictive value of preoperative cervical range of motion. We retrospectively reviewed 191 patients with cervical spondylotic myelopathy who underwent unilateral open-door CLP between January 2019 and January 2024. Patients were classified into AS (n=73) and no AS (n=118) groups. Demographic, surgical, radiographic, and clinical variables were compared. Binary logistic regression identified independent predictors, and receiver operating characteristic analysis assessed predictive performance. Compared with the no-AS group, the AS group had higher BMI (26.5±3.7 vs. 25.4±3.3 kg/m2, P=0.027), more frequent T2-weighted spinal cord increased signal intensity (64.4

OBJECTIVE:To evaluate the impact of frailty on mechanical complications following lumbar fusion surgery in elderly patients. METHODS:We retrospectively enrolled elderly patients who underwent lumbar fusion surgery between August 2021 and March 2023 and used propensity score matching (PSM) to control for confounding factors. Frailty was assessed using the 5-item modified Frailty Index (mFI-5). Univariate and multivariate logistic regression analyses were performed to compare the incidence of postoperative mechanical complications and revision rates between frail and non-frail patients. RESULTS:After PSM, a total of 113 well-matched patient pairs were obtained. Frail patients had significantly longer length of stay (LOS) and higher paraspinal muscle fat infiltration ratios (FI%) compared to non-frail patients (P < 0.05). With regard to radiographic spinopelvic alignment and postoperative functional outcomes, frail patients exhibited significantly higher preoperative pelvic tilt (PT), as well as higher Oswestry Disability Index (ODI) and Visual Analog Scale for back (VAS-back) scores at the 2-year follow-up. Multivariable regression analysis further demonstrated that frail patients were 7.4 times more likely to develop adjacent segment degeneration (ASD), 6.8 times more likely to undergo any revision surgery, and 8.3 times more likely to require revision specifically for ASD compared to non-frail patients. CONCLUSIONS:In this study, patients with frailty had significant higher rate of paravertebral muscle FI%, as well as a relatively high incidence of ASD and reoperation, highlighting its value in preoperative risk stratification.

To characterize adjacent-level disc radiomic differences and symptom associations in single-level lumbar disc herniation (LDH) on sagittal T2-weighted MRI. This retrospective single-center study included 100 patients with MRI-confirmed single-level LDH. The index herniated disc (Label 1) and cranial adjacent disc (Label 2) were segmented in all patients; the caudal adjacent disc (Label 3) was analyzed when anatomically present and a complete radiomics record was available (n = 68). A total of 107 original PyRadiomics features were extracted per ROI. Paired Wilcoxon signed-rank tests with Benjamini-Hochberg false discovery rate correction were used for Label 1 vs. Label 2, Label 1 vs. Label 3, and Label 2 vs. Label 3. Sensitivity analyses excluded shape features, repeated Label 1 vs. Label 2 in complete three-level cases, stratified by index level, and compared index with non-index discs at the same anatomical level. Symptom associations were assessed using Spearman and partial Spearman analyses. Pfirrmann grades differed across available levels in complete three-level cases (median [IQR]: 3 [2–3], 2 [2–2], and 2 [2–3] for Labels 1–3; Friedman p < 0.0001). Radiomics identified 71, 86, and 47 significant features for the three paired comparisons, respectively. Substantial non-shape differences remained after excluding shape features (59/93, 75/93, and 34/93 significant features). A non-shape summary score (PC1) at the index level was associated with VAS (rho = 0.49) and ODI (rho = 0.41), with similar adjusted results. MRI-based radiomics provides complementary quantitative disc phenotyping in single-level LDH, revealing robust adjacent-level differences and moderate cross-sectional symptom associations. Longitudinal evaluation and external validation are required before prognostic use.

To explore the effect of a nurse-led enhanced recovery care (NLERC) program on the short-term postoperative outcomes of elderly patients undergoing lumbar fusion surgery. We retrospectively reviewed a prospectively maintained database and included consecutive elderly patients (≥ 75 years) who underwent lumbar fusion surgery at a single institution from January 2020 to September 2023. All patients were divided into the historical control group (before July 2021) and the NLERC group (after September 2021). During the perioperative period, the NLERC group received enhanced recovery care, while the historical control group received conventional care. Postoperative outcomes, including physiological function recovery, complications, and length of hospital stay (LOS), were collected and compared between the two groups. A total of 168 patients were enrolled, including 92 in the NLERC group and 76 in the historical control group. There were no significant differences between the two groups in terms of demographic data, comorbidities, number of fused segments, or intraoperative blood loss. Compared with the historical control group, the NLERC group had significantly earlier times to first drinking and food intake, first anal flatus and defecation, urinary catheter removal, and first postoperative mobilization (all P < 0.05). Both total and postoperative LOS were significantly shorter in the NLERC group than in the historical control group (P < 0.05). There were no statistically significant differences in the Activities of Daily Living (ADL) scores between the two groups preoperatively and at discharge; however, the NLERC group had significantly better ADL scores than the historical control group at 1 and 3 days postoperatively (P < 0.05). The incidence of postoperative complications was lower in the NLERC group than in the historical control group. The NLERC program is associated with improved postoperative physiological recovery, shorter hospital stays, and a lower incidence of complications in elderly patients undergoing lumbar fusion surgery.

OBJECTIVE:Patient satisfaction serves as a valuable measure for evaluating outcomes from the patient's perspective. However, the factors critical for predicting satisfaction in patients with adult spinal deformity (ASD) remain elusive. This study aimed to develop and validate predictive models for assessing patient satisfaction 24 months after ASD surgery. METHODS:A total of 213 individuals diagnosed with ASD met inclusion criteria; 128 (60%) patients were randomly selected for model development (training set), and the remaining 85 (40%) were used for internal validation (test set) to assess model robustness. The primary outcome was the satisfaction score from Scoliosis Research Society-22r domains, with scores ≥ 4.5 indicating high satisfaction. Three machine learning (ML) algorithms (least absolute shrinkage and selection operator, recursive feature elimination, and Boruta) were used to identify critical variables for patient satisfaction. A logistic regression model was developed and tested based on these variables to predict personalized satisfaction. Feature importance was ranked using the Shapley Additive Explanations (SHAP) method. RESULTS:ML algorithms identified 9 key indicators of postoperative satisfaction. The predictive model demonstrated an area under the receiver operating characteristic curve of 0.846 and an accuracy of 0.812 in the test set. SHAP analysis revealed that predictors such as improved postoperative Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) function, absence of frailty, achievement of minimum clinically important difference in imaging, and enhanced WOMAC function increased the relative functional cross-sectional area, higher postoperative subtotal scores, smaller postoperative sagittal vertical axis, successful pelvic compensation, and reduced fatty infiltration significantly influenced postoperative satisfaction. CONCLUSIONS:The results of this study suggest that the developed models can provide patients with personalized prognostic information. Surgeons should consider these routinely modifiable indicators in clinical practice to guide postoperative rehabilitation.

Clinical decision-making is central to orthopedic residency training but is challenging to teach using traditional didactic lectures, which emphasize information transmission over active reasoning. Structured case-based learning (CBL) has been proposed as a learner-centered alternative that targets diagnostic reasoning, management planning, and decision-making under uncertainty. To compare the educational effectiveness of structured case-based learning versus traditional didactic lectures (TDL) in enhancing clinical decision-making among orthopedic surgery residents. A retrospective, multicenter cohort study was conducted across four postgraduate medical education programs in China. A total of 120 orthopedic residents were included (CBL and TDL, n = 60). Both groups completed an 8-week curriculum covering eight high-risk orthopedic topics with equivalent instructional time and objectives. The CBL intervention incorporated flipped pre-work, progressive case disclosure, forced decision nodes, and structured debriefing, while the TDL arm used slide-based lectures with question-and-answer periods. The primary outcome was a prespecified composite clinical decision-making score derived from standardized objective structured clinical examination (OSCE) decision stations, a Script Concordance Test, and time-to-correct-decision metrics. Secondary outcomes included knowledge performance, appropriateness of management, communication scores, retention at 8 weeks, learner satisfaction, engagement, and cognitive load. Assessors were blinded to the instructional group. Baseline characteristics and performance were comparable between groups. The CBL group achieved significantly higher composite decision-making scores than the TDL group at post-intervention and at 8-week retention, with moderate effect sizes. Secondary outcomes, including OSCE performance, reasoning under uncertainty, decision speed, knowledge scores, appropriateness of management, and communication ratings, consistently favored CBL. Learner satisfaction was higher in the CBL group, while cognitive load and attendance were similar between groups. Structured case-based learning was associated with superior educational performance compared with traditional lectures among orthopedic residents, with durable gains in decision-making. These findings support the integration of structured, decision-focused case discussions into residency didactic curricula.

Intertrochanteric fractures of the femur are often accompanied by soft tissue injuries, but their impact on postoperative functional recovery remains unclear. Preoperative magnetic resonance imaging (MRI) can accurately assess the state of soft tissues, but the independent prognostic value of relevant imaging biomarkers still requires high-quality evidence for verification. To explore the association between the biomarkers of soft tissue injury evaluated by preoperative MRI in patients with intertrochanteric femoral fractures and the postoperative functional outcomes, to screen the key imaging predictors, and to construct a robust predictive model. A retrospective analysis was conducted on patients with intertrochanteric femoral fractures who underwent surgical treatment at our hospital from January 1, 2023 to December 31, 2024. The patients were divided into the favourable prognosis group (≥ 80 points) and the unfavourable prognosis group (< 80 points) based on the Harris score at one year postoperative follow-up. Propensity score matching (1:1, cut-off value = 0.02) was used to balance the age, gender, fracture type, underlying diseases, waiting time for surgery, and internal fixation method between the two groups. After matching, 64 cases were included in each group (a total of 128 cases). Preoperative MRI examinations included: the ratio of fat infiltration area of the gluteus minimus muscle; the depth grading of the tear of the gluteus medius muscle; the relative signal intensity ratio of oedema of the femoral quadratus muscle; the continuous score of the posterior medial support complex injury; the maximum diameter of the bursa of the greater trochanter; the volume of haematoma of the fascia latae muscle; and the grading of injury of the obturator internus muscle fascia. Variables with p < 0.10 were selected for multivariate Logistic regression analysis using the backward stepwise method, and independent risk factors were identified. The multicollinearity (VIF < 5) was tested to ensure the stability of the model. The discrimination was evaluated by the receiver operating characteristic curve (ROC), and the calibration was evaluated by the Hosmer–Lemeshow test. Sensitivity analysis (changing the matching ratio and conducting 1000 Bootstrap resampling) was performed to verify the robustness of the results, and the interaction test was used to explore whether there were synergistic or antagonistic effects among the biomarkers. The baseline data of the two groups after PSM were balanced and comparable (p > 0.05). Multivariate analysis showed that the ratio of fat infiltration area in the gluteus minimus muscle (OR = 3.24, 95

To evaluate the feasibility of liposomal bupivacaine (LB) versus ropivacaine for local infiltration blocks in postoperative acute pain management following primary multilevel posterior spinal fusion. Adult patients scheduled for elective primary multilevel posterior spinal fusion were assigned to receive either multi-layer local infiltration of LB (20 ml, 266 mg) into the muscle, paravertebral fascia and subcutaneous layer or standard local infiltration block with 0.75

BACKGROUND:Older adults often have impaired physiologic reserve and are at higher risk for postoperative complications after spinal fusion surgery. OBJECTIVE:To evaluate the efficacy of multimodal prehabilitation plus Enhanced Recovery After Surgery (PREERAS) versus ERAS alone on 90-day postoperative complications in older adults undergoing elective spinal fusion. DESIGN:Multicenter, open-label, assessor-blinded, 1:1 parallel-group randomized controlled trial. (ClinicalTrials.gov: NCT06140797). SETTING:3 tertiary hospitals in China. PARTICIPANTS:Adults aged 75 years or older undergoing elective spinal fusion surgery between May 2024 and May 2025. INTERVENTION:Participants were randomly assigned to receive either preoperative Vivifrail-based, multimodal PREERAS (PREERAS group) or ERAS alone (ERAS group). The 4-week prehabilitation program integrated supervised group sessions, Vivifrail multicomponent exercise, nutritional optimization, and psychological interventions. MEASUREMENTS:The primary outcome was the occurrence of any postoperative complication within 90 days of surgery, recorded and graded per the Clavien-Dindo classification system. RESULTS:A total of 312 patients were assessed for eligibility, with 164 randomly assigned. Of the 159 patients included in the final analysis (mean age, 78.7 years; 59% women), 59 patients (74.7%) in the PREERAS group and 73 patients (91.2%) in the ERAS group experienced at least 1 complication (risk ratio, 0.80 [95% CI, 0.67 to 0.95]; risk difference, -18.0% [CI, -27.0% to -9.0%]). LIMITATIONS:Unblinded participants and clinicians. Generalizability may be limited with longer hospital stays in the Chinese health care system. CONCLUSION:The implementation of multimodal prehabilitation in 3 tertiary hospitals in China reduced 90-day postoperative complications in older adults undergoing enhanced recovery after spinal fusion surgery. However, individual sites will need to consider applicability of findings and resource requirements of prehabilitation before implementation. PRIMARY FUNDING SOURCE:Capital's Funds for Health Improvement and Research.

Study Design. A retrospective study. Objective. To characterize subtype-specific gait patterns and neuromuscular adaptations in DSD using integrated 3D motion capture and surface electromyography (sEMG). Background. Degenerative spinal diseases (DSD), including lumbar spinal stenosis (LSS), adult spinal deformity (ASD), and cervical spondylotic myelopathy (CSM), commonly impair gait in elderly patients. Materials and Methods. In this retrospective cross-sectional study, 148 participants (31 ASD, 40 LSS, 35 CSM, 42 healthy controls) underwent gait analysis with a BTS motion capture system and sEMG assessment of erector spinae, multifidus, gluteus maximus, and rectus abdominis muscles. Spatiotemporal parameters, root mean square maximum (RMSmax) and median frequencies (MF) were compared across stance and swing phases. Nonparametric statistical analyses were performed with significance at P <0.05. Results. The study included 106 patients with degenerative spinal diseases and 42 healthy elderly controls. A three-dimensional motion capture system and surface electromyography were used to synchronously analyze complete gait cycle parameters. The results showed that compared to the HC group, all three patient groups exhibited significantly reduced gait speed, lower step frequency, prolonged double-support time, increased step width, and increased asymmetry in lower limb gait parameters ( P <0.001). sEMG analysis revealed that the ASD and LSS groups had increased RMSmax values and decreased MF ( P <0.001). The asymmetry indices of bilateral muscles in all three patient groups were higher than those in the HC group ( P <0.001), indicating compromised neuromuscular control related to disease-specific pathology. Conclusion. The study systematically revealed abnormal gait parameters and distinct activation patterns of core muscles in patients with degenerative spinal conditions, along with their underlying causes. Patients in the DSD group exhibited poorer bilateral lower limb gait stability and walking speed, with different muscle activation patterns due to varying causes. Level of Evidence. Level IV