Impact of osteoporosis and Cement-Augmented fusion on adjacent spinal levels Post-Fusion Surgery: Patient-Specific finite element analysis.

Cement-augmentation is a technique commonly used during posterior lumbar instrumented fusion (PLIF) to reinforce compromised osteoporotic vertebral bone, minimize the risk of loosening screws, enhance stability, and improve overall surgical outcomes. In this study, we introduce a novel segmented vertebral body regional modeling approach to investigate the effects of osteoporosis and cement-augmented lumbar fusion on disc biomechanics at spinal levels adjacent to the fused vertebrae. Using our previously validated personalized-poroelastic-osteoligamentous FE model of the spine, fusion was simulated at L4-L5, and the biomechanics of adjacent levels were studied for 30 patients (non-osteoporotic patients (N = 15), osteoporotic patients (N = 15)). PLIF models, with and without cement-augmentation, were developed and compared after an 8 h-rest period (200 N), following a 16 h-cyclic compressive loading of 500-1000 N (40 and 20 min, respectively). Movement in different directions (flexion/ extension/ lateral bending/ axial rotation) was simulated using 10Nm moment before and after cyclic loading. The material mapping algorithm was validated by comparing the results of voxel-based and parametric models. The FE cement-augmented models, subject to daily activity loading, demonstrated significant differences in disc height loss and fluid loss as compared to non-cemented models. The calculated axial stress and fiber strain values were also significantly higher for these models. This work demonstrates that although osteoporosis does not significantly alter the time-dependent characteristics of adjacent IVDs post-surgery, cement-augmentation increases the risk of adjacent segment disease (ASD) incidence. A holistic understanding of the trade-offs and long-term complex interplay between structural reinforcement modalities, including cement augmentation, and altered biomechanics warrants further investigation.

Design of a new detachable pedicle screw based on medical optical imaging inspection to improve osteoporosis and enhance vertebral body revision effect.

Osteoporosis is a common bone disease that often leads to difficulty in vertebrae revision. Traditional pedicle screws are often complicated to operate and have poor visibility during implantation. A new detachable pedicle screw is needed to improve the revision effect. The aim of this study was to design a new detachable pedicle screw based on medical optical imaging to improve the outcome of vertebral revision in osteoporosis, and to improve operational feasibility and visibility. In this study, the parameters related to the degree of osteoporosis were obtained by optical imaging detection of the osteoporotic vertebral body. Then a new detachable pedicle screw was designed according to the test results to improve the effect of vertebral body revision. By preparing and optimizing the material and structure of the screw, it is ensured that it has sufficient mechanical strength and stability. Finally, the visibility and operability of the improved screw during implantation were verified by medical optical imaging. Compared with traditional screws, the new detachable pedicle screw can improve the vertebral body revision in the case of osteoporosis. The optical imaging test results show that the new screw has good visibility and maneuverability, providing more accurate guidance and positioning for the vertebral body revision operation.

Optimization of S2-alar-iliac screw (S2AI) fixation in adult spine deformity using a comprehensive genetic algorithm and finite element model personalized to patient geometry and bone mechanical properties.

PURPOSE: To optimize the biomechanical performance of S2AI screw fixation using a genetic algorithm (GA) and patient-specific finite element analysis integrating bone mechanical properties. METHODS: Patient-specific pelvic finite element models (FEM), including one normal and one osteoporotic model, were created from bi-planar multi-energy X-rays (BMEXs). The genetic algorithm (GA) optimized screw parameters based on bone mass quality (BM method) while a comparative optimization method maximized the screw corridor radius (GEO method). Biomechanical performance was evaluated through simulations, comparing both methods using pullout and toggle tests. RESULTS: The optimal screw trajectory using the BM method was more lateral and caudal with insertion angles ranging from 49° to 66° (sagittal plane) and 29° to 35° (transverse plane). In comparison, the GEO method had ranges of 44° to 54° and 24° to 30° respectively. Pullout forces (PF) using the BM method ranged from 5 to 18.4 kN, which were 2.4 times higher than the GEO method (2.1-7.7 kN). Toggle loading generated failure forces between 0.8 and 10.1 kN (BM method) and 0.9-2.9 kN (GEO method). The bone mass surrounding the screw representing the fitness score and PF of the osteoporotic case were correlated (R2 > 0.8). CONCLUSION: Our study proposed a patient-specific FEM to optimize the S2AI screw size and trajectory using a robust BM approach with GA. This approach considers surgical constraints and consistently improves fixation performance.

Finite element biomechanical analysis of 3D printed intervertebral fusion cage in osteoporotic population.

OBJECTIVE: To study the biomechanical characteristics of each tissue structure when using different 3D printing Cage in osteoporotic patients undergoing interbody fusion. METHODS: A finite element model of the lumbar spine was reconstructed and validated with regarding a range of motion and intervertebral disc pressure from previous in vitro studies. Cage and pedicle screws were implanted and part of the lamina, spinous process, and facet joints were removed in the L4/5 segment of the validated mode to simulate interbody fusion. A 280 N follower load and 7.5 N·m moment were applied to different postoperative models and intact osteoporotic model to simulate lumbar motion. The biomechanical characteristics of different models were evaluated by calculating and analyzing the range of motion of the fixed and cephalic adjacent segment, the stress of the screw-rod system, the stress at the interface between cage and L5 endplate, and intervertebral disc pressure of the adjacent segment. RESULTS: After rigid fixation, the range of motion of the fixed segment of model A-C decreased significantly, which was much smaller than that of the osteoporotic model. And with the increase of the axial area of the interbody fusion cages, the fixed segment of model A-C tended to be more stable. The range of motion and intradiscal pressure of the spinal models with different interbody fusion cages were higher than those of the complete osteoporosis model, but there was no significant difference between the postoperative models. On the other hand, the L5 upper endplate stress and screw-rod system stress of model A-C show a decreasing trend in different directions of motion. The stress of the endplate is the highest during flexion, which can reach 40.5 MPa (model A). The difference in endplate stress between models A-C was the largest during lateral bending. The endplate stress of models A and B was 150.5% and 140.9% of that of model C, respectively. The stress of the screw-rod system was the highest during lateral bending (model A, 102.0 MPa), which was 108.4%, 102.4%, 110.4%, 114.2% of model B and 158.5%, 110.1%, 115.8%, 125.4% of model C in flexion, extension, lateral bending, and rotation, respectively. CONCLUSIONS: For people with osteoporosis, no matter what type of cage is used, good immediate stability can be achieved after surgery. Larger cage sizes provide better fixation without significantly increasing ROM and IDP in adjacent segments, which may contribute to the development of ASD. In addition, larger cage sizes can disperse endplate stress and reduce stress concentration, which is of positive significance in preventing cage subsidence after operation. The cage and screw rod system establish a stress conduction pathway on the spine, and a larger cage greatly enhances the stress-bearing capacity of the front column, which can better distribute the stress of the posterior spine structure and the stress borne by the posterior screw rod system, reduce the stress concentration phenomenon of the nail rod system, and avoid exceeding the yield strength of the material, resulting in the risk of future instrument failure.

Prediction of 30-day and 1-year postoperative complications after balloon-assisted kyphoplasty in the elderly using the Risk Analysis Index.

OBJECTIVE: Vertebral compression fracture (VCF) is the most prevalent fragility fracture. When conservative management fails, patients may undergo balloon-assisted kyphoplasty (BAK). In BAK, an expandable balloon preforms a cavity in the fractured vertebra before injection of bone cement. The aim of this study was to compare outcomes in patients stratified by age and frailty assessed by the Risk Analysis Index (RAI). METHODS: A retrospective analysis of 334 BAK procedures (280 patients) for osteoporotic VCFs at a single institution was performed (2015-2022). Patients with at least 1 year of follow-up were eligible for inclusion. Patient demographics were recorded, including age, sex, BMI, RAI score, tobacco and steroid use, osteoporosis treatments, and bone density. Patients who underwent outpatient surgery were identified, and length of stay (LOS) was obtained for admitted patients. The rates of additional VCFs after kyphoplasty, 30-day and 1-year postoperative complications, and reoperation were identified. RESULTS: The overall rates of additional VCFs, 30-day postoperative complications, 1-year postoperative complications, and reoperation were 16.2%, 5.1%, 12.0%, and 6.3%, respectively. Patients were stratified by age: nonelderly (< 80 years; 220 patients, 263 treated vertebrae) and elderly (≥ 80 years; 60 patients, 71 treated vertebrae). There were no differences in sex (p = 0.593), tobacco use (p = 0.973), chronic steroid use (p = 0.794), treatment for osteoporosis (p = 0.537), bone density (p = 0.056), outpatient procedure (p = 0.273), and inpatient LOS (p = 0.661) between both groups. There were also no differences in the development of additional VCFs (p = 0.862) at an adjacent level (p = 0.739) or remote level (p = 0.814), 30-day and 1-year postoperative complications (p = 0.794 and p = 0.560, respectively), and reoperation rates (p = 0.420). Patients were then analyzed by RAI: nonfrail (RAI score < 30; 203 patients, 243 treated vertebrae) and frail (RAI score ≥ 31; 77 patients, 91 treated vertebrae). There were no differences in tobacco use (p = 0.959), chronic steroid use (p = 0.658), treatment for osteoporosis (p = 0.560), bone density (p = 0.339), outpatient procedure (p = 0.241), inpatient LOS (p = 0.570), and development of additional VCFs (p = 0.773) at an adjacent level (p = 0.390) or remote level (p = 0.689). However, rates of 30-day and 1-year postoperative complications in frail patients more than doubled in comparison with nonfrail patients (p = 0.031 and p = 0.007, respectively), and frail patients trended toward reoperation (p = 0.097). CONCLUSIONS: BAK is a safe treatment in the elderly, and age alone should not be used as an exclusion criterion during patient selection. Frailty, which can be assessed reliably using the RAI, may serve as a better predictor for postoperative complications and reoperation following BAK.

Imaging in revision total knee arthroplasty: A novel 3D classification system for tibial bone defects.

PURPOSE: The primary purpose of the study was to use pre-revision total knee arthroplasty (TKA) computer-tomography (CT)-images to analyse typical tibial bone defects and create a new schematic three-dimensional (3D)-classification system. The secondary purpose was to investigate the association between defect size and implant selection at the time of revision surgery. METHODS: Eighty-four patients with preoperative CT-scans underwent revision of a primary TKA. CT-image segmentation with the 3D-Slicer Software was performed retrospectively, and a new three-dimensional classification system was used to grade tibial bone defects. The location of tibial bone defects was recorded for all cases. Volumetric 3D bone defect measurements were used to investigate the association between the bone defect volume, the indication for rTKA, and the use of modular revision components. The t-test, the Mann-Whitney-U test, and the Fisher's exact-test were used for group comparisons, and the Kruskal-Wallis test was used for multiple group comparisons. RESULTS: The most common anatomic regions for both contained and uncontained tibial bone defects were the anteromedial epiphysis (N = 50; mean epiphyseal-defect: 5.9 cm³) and metaphysis (N = 15; mean metaphyseal-defect: 9.6 cm³). A significant association was found between patients with preoperative metaphyseal defects (N = 22) and the use of tibial augments (N = 7) (p = 0.04). The use of cones/sleeves was associated with a significantly increased 3D-CT volume of the preoperative metaphyseal bone defects (p = 0.04). Patients with osteoporosis had significantly larger volumetric defects in the metaphysis (p = 0.01). CONCLUSION: Our results emphasise the importance of considering the three-dimensional nature of tibial defects in rTKA. The findings suggest that an understanding of the volume of the defect size through CT imaging can predict the need for augments and cones/sleeves and, especially in patients with osteoporosis can help the surgeon identify larger metaphyseal defects and ensure optimal metaphyseal fixation through appropriate implant selection. LEVEL OF EVIDENCE: Level III, retrospective cohort study.

Impact of osteoporotic risk in women undergoing transcatheter aortic valve replacement.

Low body weight and advanced age are reported to be among the best predictors of osteoporosis, and osteoporosis self-assessment tool (OST) values are calculated using a simple formula to identify postmenopausal women at increased risk of osteoporosis. In our recent study, we demonstrated an association between fractures and poor outcomes in postmenopausal women following transcatheter aortic valve replacement (TAVR). In this study, we aimed to investigate the osteoporotic risk in women with severe aortic stenosis and determined whether an OST could predict all-cause mortality following TAVR. The study population comprised 619 women who underwent TAVR. Compared to a quarter of patients with diagnosis of osteoporosis, 92.4% of participants were at high risk of osteoporosis based on OST criteria. When divided into tertiles based on OST values, patients in tertile 1 (lowest OST) displayed increased frailty, a higher incidence of multiple fractures, and greater Society of Thoracic Surgeons scores. Estimated all-cause mortality survival rates 3 years post-TAVR were 84.2 ± 3.0%, 89.5 ± 2.6%, and 96.9 ± 1.7% for OST tertiles 1, 2, and 3, respectively (p = 0.001). Multivariate analysis showed that the OST tertile 3 was associated with decreased risk of all-cause mortality compared with OST tertile 1 as the referent. Notably, a history of osteoporosis was not associated with all-cause mortality. Patients with high osteoporotic risk are highly prevalent among those with aortic stenosis according to the OST criteria. OST value is a useful marker for predicting all-cause mortality in patients undergoing TAVR.

Evaluating alternatives to dual-energy x-ray absorptiometry for assessing bone quality in patients undergoing spine surgery.

OBJECTIVE: The purpose of this study was to compare and contrast lumbar bone quality and osteoporosis/osteopenia screening results via dual-energy x-ray absorptiometry (DEXA), CT, and MRI. METHODS: A consecutive series of 426 candidates screened for lumbar disc replacement over a 5-year period beginning in 2018 was reviewed. Patients with a preoperative lumbar spine DEXA scan and a CT and/or MRI scan were included. The primary outcome measures included the bone mineral density (BMD) and osteoporosis or osteopenia classification from DEXA scans, Hounsfield units (HUs) for CT, and vertebral bone quality (VBQ) assessment for MRI. Patients were included if they had a DEXA scan within 1 year of an MRI or CT scan. DEXA BMD scores from composite or level-by-level reports were recorded. Asynchronous MRI and CT measurements were conducted using PACS. Interrater and intrarater reliability scores were generated for both CT and MRI measurements and ranged from 1.000 for MRI L1-4 scans to 0.683 for MRI VBQ. RESULTS: All 3 types of scans were statistically significantly correlated with one another; however, CT was more strongly correlated with the lumbar DEXA value (r = 0.439, p < 0.001). The correlation between MRI VBQ and DEXA was -0.103, (p < 0.045). The CT level-by-level measurements correlate with the corresponding level-by-level DEXA BMD values (correlation ranging from 0.531 to 0.289, p < 0.001 to p = 0.007). CT HU values were more strongly related to osteoporosis/osteopenia classification based on DEXA T-scores than were MRI VBQ values. Receiver operating characteristic analyses found that the area under the curve was 0.817 for CT and 0.539 for MRI. CONCLUSIONS: These results demonstrate that CT HUs more closely correlate to DEXA scores than MRI VBQ in this population of patients undergoing surgery for symptomatic disc degeneration. Thus, CT may be an alternative to DEXA for assessing VBQ in this population.

Sex differences in the accuracy of vertebral bone quality score assessing bone density in patients undergoing lumbar spinal fusion.

OBJECTIVE: Low bone mineral density (BMD) significantly increases the risk of complications in patients undergoing spinal fusion. Existing evidence indicates that traditional dual-energy x-ray absorptiometry (DEXA) and quantitative CT (QCT) screening are underutilized in spine surgery. The MRI-based vertebral bone quality (VBQ) score provides a tool for primary screening of bone density. The validity of this score as a predictor across sexes has not been investigated. This study aimed to explore the effect of sex on the diagnostic efficacy of the VBQ in predicting osteopenia/osteoporosis and whether a sex-specific threshold exists. METHODS: In this retrospective cohort study, patients who underwent lumbar fusion at a tertiary care center were reviewed. VBQ was obtained by noncontrast T1-weighted MRI. Patients were stratified according to sex and bone density. Data were analyzed between the groups. Pearson correlation analysis and linear regression were used to analyze the correlation between the VBQ and DEXA T values. Receiver operating characteristic (ROC) curve analysis, including area under the curve (AUC) calculation, was used to evaluate the predictive performance of VBQ for low BMD in both sexes. RESULTS: A total of 271 patients (92 male, 179 female patients) were analyzed. The correlation coefficient between VBQ and the lowest T value was -0.40 for male and -0.554 for female patients. In comparing the bone density subgroups, among male patients a significant difference in the VBQ scores was observed only between the normal and osteoporosis subgroups (p = 0.012). VBQ demonstrated statistically significant differences among female patients across all three subgroups (p < 0.001). The ROC analysis revealed that the predictive performance of VBQ in detecting low BMD was more consistent with the gold-standard DEXA results in female than in male patients (AUC 0.647 vs AUC 0.823, p = 0.02). The optimal thresholds were similar in both sexes. CONCLUSIONS: Compared with male patients, VBQ has better discrimination between female patients with low BMD and those with normal bone density. Although the correlation between VBQ and bone density is weaker in male than in female patients, the optimal thresholds are similar in both sexes.

[Construction and evaluation of a nomogram prediction model for periprosthetic fractures after total hip arthroplasty].

OBJECTIVE: To construct and evaluate nomogram prediction model for periprosthetic fractures in patients undergoing total hip arthroplasty (THA). METHODS: A total of 538 patients who underwent THA from April 2013 to February 2019 were selected as the research subjects, including 318 males and 220 females, aged 40 to 60 years old with an average age of (50.79±6.37) years old. All patients with THA were divided into non-fracture group (506 patients) and fracture group (32 pathents) according to the 3-year follow-up results. Univariate and multivariate Logistic regression analyses were performed to analyze the influencing factors of postoperative periprosthetic fractures in patients with THA. A nomogram prediction model for periprosthetic fractures in patients undergoing THA was constructed, and the validity and discrimination of the prediction model were evaluated. RESULTS: The proportion of patients with osteoporosis, trauma history, and hip revision in the fracture group were higher than those in the non-fracture group(P<0.05), and the proportion of bone cement prosthesis was lower than that in the non-fracture group(P<0.05). The osteoporosis status[OR=4.177, 95%CI(1.815, 9.617), P<0.05], trauma history[OR=7.481, 95%CI(3.104, 18.031), P<0.05], and hip revision[OR=11.371, 95%CI(3.220, 40.153, P<0.05] were independent risk factors for postoperative periprosthetic fractures in patients undergoing THA, cemented prosthesis [OR=0.067, 95%CI(0.019, 0.236), P<0.05] was an independent protective factor for postoperative periprosthetic fractures in patients undergoing THA(P<0.05). Hosmer-Lemeshow goodness of fit test showed that χ2=7.864, P=0.325;the area under the curve (AUC) for periprosthetic fractures in patients undergoing THA was 0.892 with a sensitivity of 87.5% and a specificity of 77.7% by receiver operating characteristic(ROC) curve. CONCLUSION: The nomogram prediction model for periprosthetic fractures after THA constructed in this study has good discrimination, which is beneficial to clinical prediction of periprosthetic fractures in patients undergoing THA, and facilitates individualized fracture prevention.

Oblique lateral interbody fusion combined with unilateral versus bilateral posterior fixation in patients with osteoporosis.

PURPOSE: To compare the clinical efficacy of oblique lateral interbody fusion (OLIF) combined with unilateral (UPSF) and bilateral pedicle screw internal fixation (BPSF) in patients with osteoporosis. METHODS: Clinical data of 57 patients who underwent single-segment OLIF surgery with a clear diagnosis of osteoporosis from December 2018 to May 2021 were retrospectively analyzed, of which 27 patients underwent OLIF + UPSF and 30 patients underwent OLIF + BPSF. Surgical technique-related indexes were recorded, including operative time, operative blood loss and postoperative hospital stay; clinical outcome-related indexes included postoperative complications, Visual analogue scale (VAS) and Oswestry disability index (ODI) at preoperative, 1 week, 1 month, 3 months, and 12 months postoperative follow-up; and imaging outcome-related indexes included the measurement of preoperative and postoperative segmental lordosis (SL), and observation of the degree of cage subsidence and bone graft fusion. RESULTS: The surgery was successfully performed in 57 patients, and there was no statistical difference in operative blood loss and postoperative hospital stay between UPSF group and BPSF group (P > 0.05). In terms of operative time, there was a significant difference (UPSF group: 92.30 ± 11.03 min, BPSF group: 119.67 ± 16.41, P < 0.05). Postoperative VAS and ODI scores exhibited significant improvement (P < 0.05). At the 12 months postoperative follow-up, the VAS and ODI scores in the BPSF group were significantly better than those in the UPS group (P < 0.05). Compared with the preoperative images, the SL was significantly improved in both groups after surgery (P < 0.05). At 6 months postoperatively, the fusion rate in the UPSF group was significantly lower than that in the BPSF group (P < 0.05). At 1 year postoperatively, the fusion rate in the UPSF group was not significantly different from that in the BPSF group (P > 0.05). At 1 year postoperatively, the rate and degree of cage subsidence was higher in the UPSF group than in the BPSF group (P < 0.05). CONCLUSION: In the long term, OLIF combined with bilateral posterior fixation applied to the osteoporosis patients is superior to OLIF surgery combined with unilateral posterior fixation in terms of clinical and imaging outcomes. It is effective in improving pain relief and functional improvement, accelerating bone graft fusion, and reducing cage subsidence compared with UPSF.

Application of cement-augmented pedicle screws in elderly patients with spinal tuberculosis and severe osteoporosis: a preliminary study.

OBJECTIVE: Surgical management of elderly patients with spinal tuberculosis and severe osteoporosis is challenging. Cement-augmented pedicle screws (CAPS) have been specifically designed for elderly patients with osteoporotic spines. Herein, we investigated the feasibility of CAPS applied in elderly patients with spinal tuberculosis and severe osteoporosis. METHODS: We retrospectively analyzed data of patients with spinal tuberculosis and severe osteoporosis between January 2017 and January 2021. Surgical data, including surgical duration and intraoperative blood loss, were recorded. Radiological parameters, such as correction of regional kyphotic angle and screw loosening, were also evaluated. Additionally, visual analog scores (VAS) and Oswestry disability index (ODI) were used to evaluate back pain and functional recovery, respectively. Erythrocyte sedimentation (ESR) and C-reactive protein (CRP) concentrations were detected to assess tuberculosis activity. The presence of complications and fusion rate was also assessed. RESULTS: A total of 15 patients were included in this study. The surgical duration was 263.0 ± 56.2 min, with an average blood loss of 378.7 ± 237.0 ml. The correction of regional kyphotic angle was 12.4° ± 15.0°, and it was well maintained until the final follow-up. The mean VAS decreased from 6.0 ± 1.2 points to 0.5 ± 0.6 points, and ODI reduced from 37.8% ± 7.6% to 8.3% ± 2.8% (P < 0.01). At the final follow-up, ESR and CRP levels were within normal range. Bony fusion occurred in all patients, with an average fusion duration of 8.8 ± 1.5 months. No cases of pedicle screw pullout, screw loosening, or pseudoarthrosis occurred. Tuberculosis recurrence and dissemination were not observed during the follow-ups. CONCLUSIONS: CAPS fixation is an effective and safe technique to achieve solid fixation and favorable clinical outcomes in elderly patients with spinal tuberculosis and severe osteoporosis.

Cement-augmented pedicle screw for thoracolumbar degenerative diseases with osteoporosis: a systematic review and meta-analysis.

BACKGROUND: Cement-augmentation pedicle screws have been widely used in spinal internal fixation surgery combined with osteoporosis in recent years, which can significantly improve the fixation strength, but compared with conventional methods, whether it has more advantages is still inconclusive of evidencebased medicine. To systematically evaluate the efficacy and safety of cement-augmented pedicle screw in the treatment of thoracolumbar degenerative diseases with osteoporosis. METHODS: We searched PubMed, Embase, and Cochrane Library for studies published from the establishment of the database up until June 2023. We included studies that concerning the cement-augmented pedicle screw and the traditional pedicle screw placement for thoracolumbar degenerative diseases with osteoporosis. We excluded repeated publication, researches without full text, incomplete information or inability to conduct data extraction and animal experiments, case report, reviews and systematic reviews. STATA 15.1 software was used to analyze the data. RESULTS: A total of 12 studies were included in this meta-analysis. The sample size of patients were totally 881, of which, 492 patients in cement-augmented screw group and 389 patients in conventional screw group. Meta-analysis results showed that Japanese Orthopaedic Association (JOA) score (WMD = 1.69, 95% CI 1.15 to 2.22), intervertebral space height (WMD = 1.66, 95% CI 1.03 to 2.29) and post-operation fusion rate (OR = 2.80, 95% CI 1.49 to 5.25) were higher in the cement-augmented screw group than those in the conventional screw group. Operation time was longer in the cement-augmented screw group than that in the conventional screw group (WMD = 15.47, 95% CI 1.25 to 29.70). Screw loosening rate was lower in the cement-augmented screw group than those in the conventional screw group (OR = 0.13, 95% CI 0.07 to 0.22). However, hospitalization time, intraoperative blood loss and Visual analog scale (VAS) score were not significantly different between the two groups (P > 0.05). CONCLUSION: Compared with conventional pedicle screw placement, cement-augmented pedicle screw is more effective in the treatment of osteoporotic thoracolumbar degenerative disease by improving fusion rate and interbody height, reducing the incidence of screw loosening, and elevating long-term efficacy.

Disparities in Parathyroidectomy: Who Receives Appropriate Treatment for Primary Hyperparathyroidism?

INTRODUCTION: Parathyroidectomy is underperformed despite clear benefits in primary hyperparathyroidism (PHPT). We evaluated disparities in receipt of parathyroidectomy following PHPT diagnosis to explore barriers to care. METHODS: Adults diagnosed with PHPT 2013-2018 at a health system were identified. Recommended indications for parathyroidectomy include age ≤50 y, calcium >11 mg/dL, or the presence of nephrolithiasis, hypercalciuria, nephrocalcinosis, decreased glomerular filtration rate, osteopenia, osteoporosis, or pathological fracture 1 y prior to diagnosis. Kaplan-Meier analysis assessed rates of parathyroidectomy within 12 mo following diagnosis as well as median time to parathyroidectomy, and multivariable Cox proportional hazards analyses assessed factors associated with undergoing parathyroidectomy. RESULTS: Of 2409 patients, 75% were females, 12% aged ≤50 y, and 92% non-Hispanic White, while 52% had Medicaid/Medicare, 36% were commercial/self-pay or uninsured, and 12% unknown. Parathyroidectomy was performed within 1 y in 50% of patients. Within the 68% that met recommendations, parathyroidectomy was performed within 1 y in 54%; median time from diagnosis to surgery was shorter for males, patients aged ≤50 y, commercial/self-pay/no insurance patients (versus Medicaid/Medicare), and those with fewer comorbidities, P < 0.05. Multivariable analysis demonstrated non-Hispanic White patients and those with commercial/self-pay/uninsured were more likely to undergo parathyroidectomy after adjusting for comorbidity, age, and facility site. Among those strongly indicated, patients not on Medicare/Medicaid and aged ≤50 y were more likely to undergo parathyroidectomy after adjusting for race, comorbidity, and facility site. CONCLUSIONS: Disparities in parathyroidectomy for PHPT were observed. Insurance type was associated with undergoing parathyroidectomy; patients on governmental insurance were less likely to undergo surgery and waited longer for surgery despite strong indications. Barriers to referral and access to surgery should be investigated and addressed to optimize all patients' access to care.

Efficacy of minimally invasive transforaminal lumbar interbody fusion plus cement-augmented pedicle screw fixation in the treatment of degenerative lumbar spine disease with osteoporosis in the elderly.

OBJECTIVE: The aim of this study was to evaluate the efficacy of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) plus cement-augmented pedicle screw fixation in the treatment of degenerative lumbar spine disease with osteoporosis in the elderly. PATIENTS AND METHODS: From February 2020 to January 2021, 40 elderly patients with degenerative lumbar spine disease with osteoporosis admitted to our hospital were randomly assigned (1:1) to receive either MIS-TLIF plus cement-augmented pedicle screw fixation (group A) or TLIF plus cement augmentation (group B), with 19 cases in group A and 21 cases in group B. Outcome measures included visual analogue scale (VAS), Oswestry Dysfunction Index (ODI) and Japanese Orthopedic Association Scores (JOA), operative duration, intraoperative bleeding, postoperative drainage volume, and the incidence of complications. Frontal and lateral radiographs of the lumbar spine and computed tomography (CT) were performed 3 days after surgery to observe the distribution of bone cement. At 12 months postoperatively, the fusion of the bone graft was evaluated according to the Bridwell intervertebral fusion criteria based on the lumbar frontal and lateral radiographs. RESULTS: All 40 cases completed the surgery successfully and were followed up for 12 months. The two groups did not differ significantly in terms of operative duration (p>0.05). MIS-TLIF plus cement-augmented pedicle screw fixation was associated with significantly less intraoperative bleeding volume (142.25±40.93 mL) and (76.25±17.54 mL) vs. TLIF plus cement augmentation (322.00±93.45 mL, 159.75±54.74 mL) (p<0.05). The difference in the VAS scores, ODI, and JOA scores between the two groups preoperatively and at the final follow-up showed no statistical significance (p>0.05). Patients receiving MIS-TLIF plus cement-augmented pedicle screw fixation had significantly lower VAS scores and ODI and higher JOA scores vs. TLIF plus cement augmentation (p<0.05). The lumbar frontal and lateral radiographs and CT of the two groups 3 days after surgery showed good cement distribution and no cement leakage. At the final follow-up, no complications were seen in group A, and there was one case of intervertebral cement leakage in group B. The intervertebral graft fusion was grade I in both groups. CONCLUSIONS: MIS-TLIF plus cement-augmented pedicle screw fixation shortens the operative time, alleviates postoperative pain, facilitates operative lumbar spine function restoration, and provides favorable intervertebral implant fusion.

Effectiveness of Teriparatide for Spine Fusion in Osteoporotic Patient: A Systematic Review and Meta-Analysis of Comparative Studies.

OBJECTIVE: Our goal was to assess teriparatide's (TP) effectiveness in improving radiographic and functional outcomes after spinal fusion surgery. This meta-analysis included randomized controlled trials (RCTs) and comparative cohort studies. The findings provide valuable insights and guidance for surgeons treating osteoporotic patients undergoing spinal fusion surgery. METHODS: We conducted a systematic review to assess TP's efficacy in spinal fusion surgery for osteoporosis. Through thorough selection, data extraction, and quality assessment, we employed network meta-analysis to evaluate radiographic outcomes (fusion rate, screw loosening, vertebral fracture) and changes in bone mineral density measured by Hounsfield units. Functional outcomes were assessed using the Oswestry Disability Index scales. Our study aims to comprehensively understand TP's impact and effectiveness in spinal fusion surgery. RESULTS: A total of 868 patients were included in the analysis. All patients underwent thoracolumbar internal fixation fusion surgery and were divided into following 2 groups: the TP treatment group and the control group. The results revealed significant differences in radiological outcomes. The fusion rate showed a significant difference, as well as screw loosening, and bone mineral density measured in Hounsfield units. However, there was no significant difference in vertebral fracture. The TP group demonstrated favorable effects with statistical significance. In terms of functional outcomes, there was no significant difference in the assessment of Oswestry Disability Index scores between the 2 treatment groups. CONCLUSIONS: The meta-analysis demonstrated that the TP group exhibited significantly better outcomes, particularly in radiological measures, when compared to the control group. The use of TP in spinal fusion surgery shows promise in reducing postoperative complications and providing overall benefits.

Dual-Plate Fixation for Proximal Humerus Fractures With Unstable Medial Column in Patients With Osteoporosis.

OBJECTIVES: To compare radiological and clinical outcomes between lateral locking plate (LLP) and dual-plate fixation (LLP and additional medial buttress plate) for proximal humerus fractures with medial column comminution and varus deformity in patients with osteoporosis. DESIGN: Retrospective. SETTING: Academic medical center. PATIENTS/PARTICIPANTS: Overall, 52 patients were enrolled. Of these, 26 patients underwent dual-plate fixation. The control group (LLP) was matched to the dual-plate group for age, sex, injured side, and fracture type. INTERVENTION: Patients in the dual-plate group were treated with LLP and medial buttress plate, whereas patients in the LLP group were treated with only an LLP. MAIN OUTCOME MEASUREMENTS: Demographic factors, operative time, and level of hemoglobin of the 2 groups obtained from medical records. Changes in the neck-shaft angle and the development of postoperative complications were recorded. Clinical outcomes were measured based on the visual analog scale; American Shoulder and Elbow Surgeons; Disabilities of the Arm, Shoulder, and Hand; and Constant-Murley scores. RESULTS: The operation time and hemoglobin loss did not differ significantly between the groups. Radiographic evaluation showed a significantly lower change in neck-shaft angle in the dual-=plate group than in the LLP group. The dual-plate group also showed better Disabilities of the Arm, Shoulder, and Hand; American Shoulder and Elbow Surgeons; and Constant-Murley scores than the LLP group. CONCLUSION: Fixation using additional medial buttress plate with LLP may be considered for treating proximal humerus fractures in patients with an unstable medial column, varus deformity, and osteoporosis. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.