Rheological Analysis and Evaluation of Measurement Techniques for Curing Poly(Methyl Methacrylate) Bone Cement in Vertebroplasty.

Vertebroplasty is a minimally invasive surgical procedure used to treat vertebral fractures, which conventionally involves injecting poly(methyl methacrylate) (PMMA) bone cement into the fractured vertebra. A common risk associated with vertebroplasty is cement leaking out of the vertebra during the injection, which may occur due to a lack of understanding of the complex flow behavior. Therefore, experiments to quantify the cement's flow properties are necessary for understanding and proper handling of the bone cement. In this study, we aimed to characterize the behavior of PMMA bone cement in its curing stages to obtain parameters that govern the flow behavior during injection. We used rotational and oscillatory rheometry for our measurements, as well as a custom-made injector setup that replicated a typical vertebroplasty setting. Our results showed that the complex viscoelastic behavior of bone cement is significantly affected by deformations and temperature. We found that the results from rotational tests, often used for characterizing the bone cement, are susceptible to measurement artifacts caused by wall slip and "ridge"-like formations in the test sample. We also found the Cox-Merz rule to be conditionally valid, which affects the use of oscillatory tests to obtain the shear-thinning characteristics of bone cement. Our findings identify important differences in the measured flow behavior of PMMA bone cement when assessed by different rheological methods, an understanding that is crucial for its risk-free usage in downstream medical applications.

Effects of Combined Application of Percutaneous Vertebroplasty and Zoledronic Acid on Bone Mineral Density, Bone Metabolism, NPY and PGE2 in Elderly Patients with Osteoporotic Lumbar Vertebral Compression Fracture.

OBJECTIVE: To investigate the effects of the combined application of percutaneous vertebroplasty and zoledronic acid on bone mineral density (BMD), bone metabolism, neuropeptide Y (NPY) and prostaglandin E2 (PGE2) in elderly patients with osteoporotic lumbar vertebral compression fracture (OVCF). METHODS: The medical records of 118 elderly patients with OVCF who received treatment at our hospital from March 2018 to March 2020 were collected and analyzed retrospectively. Vertebral body height, spinal function, pain degree, and lumbar BMD were compared between the two groups upon admission and three years after the operation. Additionally, the levels of bone-specific alkaline phosphatase (BALP), 25-hydroxyvitamin D (25-(OH)D), beta collagen degradation fragments (ß-CTx), neuropeptide Y (NPY), and prostaglandin E2 (PGE2) in the two groups were measured at admission and three years after the operation. Furthermore, complications in the two groups within three years after the operation were documented. RESULTS: After three years post-operation, the combination group showed a significantly greater improvement in vertebral body height compared to the control group (P<0.05). Moreover, the combination group exhibited a significantly lower Oswestry Disability Index (ODI) score compared to the control group (P<0.05). CONCLUSION: In elderly patients with OVCF, the combined use of zoledronic acid and percutaneous vertebroplasty is effective in improving lumbar function, BMD, and bone metabolism indices, while reducing pain and the levels of NPY and PGE2.

Lower psoas mass indicates worse prognosis in percutaneous vertebroplasty-treated osteoporotic vertebral compression fracture.

The correlation between lower psoas mass and the prognosis of osteoporotic vertebral compression fractures (OVCF) is still unclear. This study aims to investigate the impact of lower psoas mass on the prognosis of patients undergoing percutaneous vertebroplasty (PVP). One hundred and sixty-three elderly patients who underwent single-segment PVP from January 2018 to December 2021 were included. The psoas to L4 vertebral index (PLVI) via MRI were measured to assess psoas mass. Patients were divided into high PLVI (> 0.79) and low PLVI (≤ 0.79) groups based on the median PLVI in the cohort. The basic information (age, gender, body mass index (BMI) and bone mineral density (BMD)), surgical intervention-related elements (duration of operation, latency to ambulation, period of hospital stay, and surgical site), postoperative clinical outcomes (Visual Analog Scale (VAS) scores, Oswestry Disability Index (ODI) scores, Japanese Orthopaedic Association (JOA) scores), and incidence of secondary fractures) were compared. Patients showed no statistically significant differences in terms of age, gender, surgical sute, BMI, BMD and preoperative VAS, ODI, JOA scores (P > 0.05) between the two groups. However, there were significant differences in terms of latency to ambulation, period of hospital stay (P < 0.05). VAS, ODI, and JOA scores at 1, 6, and 12 months after surgery showed that the high PLVI group had significantly better outcomes than the low PLVI group (P < 0.05). Additionally, the low PLVI group had a significantly higher incidence of recurrent fracture (P < 0.05). Lower psoas mass can reduce the clinical effect of PVP in patients with osteoporotic vertebral compression fractures, and is a risk factor for recurrent vertebral fracture.

Instrumental Evaluation of the Effects of Vertebral Consolidation Surgery on Trunk Muscle Activations and Co-Activations in Patients with Multiple Myeloma: Preliminary Results.

Multiple myeloma (MM) patients complain of pain and stiffness limiting motility. To determine if patients can benefit from vertebroplasty, we assessed muscle activation and co-activation before and after surgery. Five patients with MM and five healthy controls performed sitting-to-standing and lifting tasks. Patients performed the task before and one month after surgery. Surface electromyography (sEMG) was recorded bilaterally over the erector spinae longissimus and rectus abdominis superior muscles to evaluate the trunk muscle activation and co-activation and their mean, maximum, and full width at half maximum were evaluated. Statistical analyses were performed to compare MM patients before and after the surgery, MM and healthy controls and to investigate any correlations between the muscle's parameters and the severity of pain in patients. The results reveal increased activations and co-activations after vertebroplasty as well as in comparison with healthy controls suggesting how MM patients try to control the trunk before and after vertebroplasty surgery. The findings confirm the beneficial effects of vertebral consolidation on the pain experienced by the patient, despite an overall increase in trunk muscle activation and co-activation. Therefore, it is important to provide patients with rehabilitation treatment early after surgery to facilitate the CNS to correctly stabilize the spine without overloading it with excessive co-activations.

[A controlled clinical study of vertebroplasty for the treatment of osteoporotic vertebral compression fractures after self-made spinal positioner and manual reduction].

OBJECTIVE: To explore clinical effect of manipulation reduction combined with vertebral plasty on osteoporotic compression fractures (OVCFs). METHODS: Totally 61 patients with OVCFs treated from January 2022 to March 2024 were randomly divided into self-made spinal locator positioning with manipulation reduction group (treatment group) and traditional Kirchner positioning group (control group). There were 30 patients in treatment group, including 4 males and 26 females, aged from 61 to 87 years old with an average of (73.61±7.17) years old;body mass index (BMI) ranged from 15.24 to 28.89 kg·m-2 with an average of (23.90±3.20) kg·m-2;bone mineral density T value ranged from -4.90 to -2.50 SD with an avergae of (-3.43±0.75) SD;fracture to operation time was 6.50 (4.00, 10.25) d;10 patients were gradeⅠ, 13 patients were gradeⅡ, and 7 patients were grade Ⅲ according to Genant classification of fracture compression. There were 31 patients in control group, including 7 males and 24 females, aged from 61 to 89 years old with an average of (73.63±8.77) years old;BMI ranged from 18.43 to 27.06 kg·m-2 with an average of (23.67±2.35) kg·m-2;bone mineral density T value ranged from -4.60 to -2.50 SD with an avergae of (-3.30±0.68) SD;fracture to operation time was 6.00 (3.00, 8.00) d;11 patients were gradeⅠ, 9 patients were gradeⅡ, and 11 patients were grade Ⅲ according to Genant classification of fracture compression. The puncture times, X-ray fluoroscopy times and puncture time between two groups were observed and compared. Visual analogue scale (VAS), Japanese Orthopaedic Association (JOA) and timed up and go test (TUGT) were observed and compared before operation, 3 d and 1 month after operation. RESULTS: All patients were followed up for 1 to 3 months with an average of (2.10±0.80) months. Puncture times, X-ray fluorosecopy times and puncture time in treatment group were 5.00(4.00, 6.00) times, (29.53±5.89) times and 14.83(12.42, 21.20) min, respectively, while those in control group were 7.00(6.00, 8.00) times, (34.58±5.33) times, 22.19(17.33, 27.01) min, treatment group was better than those of control group (P<0.05). There were no significant differences in preoperative VAS, JOA and TUGT between two groups(P>0.05). VAS, JOA and TUGT in both groups were significantly improved after opeation(P<0.05). On the third day after operation, JOA score of treatment group was 23.00 (20.75, 25.00), which was higher than that of control group 20.00(19.00, 23.00)(P<0.05). TUGT of treatment group was 6.26(5.86, 6.57) s, which was better than that of control group 6.90(6.80, 7.14) s (P<0.05). Bone cement leakage occurred with 1 patient in treatment group and 2 patients in control group. CONCLUSION: The optimal scheme of self-made spinal locators for locating descending verteboplasty combined with traditional Chinese medicine reduction manipulation for OVCF patients could reduce the number of intraoperative puncture times, shorten puncture times and reduce number of X-ray fluoroscopy times, and have advantages over the simple positioning of Kirschn's needle in restoring short-term lumbar function and standing and walking ability of postoperative patients.

[Comparsion of bone setting technique combined with percutaneous vertebroplasty and percutaneous kyphoplasty for the treatment of osteoporotic vertebral compression fractures].

OBJECTIVE: To explore clinical efficacy of osteoplasty combined with percutaneous vertebroplasty(PVP) and percutaneous kyphoplasty (PKP) alone in treating osteoporosis vertebral compression fractures (OVCFs). METHODS: The clinical data of 80 patients with single-level OVCFs treated from January 2021 to June 2022 were retrospectively analyzed, and were divided into treatment group and control group according to different surgical methods, 40 patients in each group. In treatment group, there were 24 males and 16 females, aged from 60 to 83 years old with an average of (70.43±7.31) years old;bone mineral density ranged from -3.30 to -2.50 SD with an average of(-2.84±0.24) SD;1 patient with T10, 4 patients with T11, 11 patients with T12, 7 patients with L1, 7 patients with L2, 5 patients with L3, 3 patients with L4, 2 patients with L5;bone setting technique combined with PVP were performed. In control group, there were 27 males and 13 females, aged from 60 to 82 years old with an average of (68.98±6.94) years old;bone mineral density ranged from -3.40 to -2.50 SD with an average of (-2.76±0.23) SD;2 patients with T10, 3 patients with T11, 13 patients with T12, 11 patients with L1, 5 patients with L2, 3 patients with L3, 2 patients with L4, 1 patient with L5;simple PKP were peformed. Visual analogue scale (VAS) and lumbar Oswestry disability index (ODI) were compared between two groups before operation, 3 days, 3 and 12 months after operation. The changes of local kyphotic angle, vertebral wedge angle and vertebral anterior margin height ratio were compared between two groups before operation, 3 days and 12 months after operation. RESULTS: All patients were successfully completed operation. Treatment group were followed up from 13 to 22 months with an average of (16.82±2.14) months, and control group were followed up from 13 to 23 months with an average of (16.45±2.56) months. Three patients were occurred bone cement leakage in treatment group, while 1 patient were occurred bone cement leakage and 1 patient occurred sensory disturbance of lower limb skin in control group;there were no significant difference in complications between two groups (P>0.05). There were no significant difference in preoperative VAS and ODI between two groups (P>0.05). At 3 days after operation, VAS of treatment group 3.68±0.62 was significantly higher than that of control group 4.00±0.72 (P<0.05). There were no significant difference in VAS and ODI between two groups at 3 and 12 months after operation (P>0.05). There were no significant difference in local kyphotic angle, vertebral wedge angle and vertebral anterior margin height between two groups at 3 days and 12 months after operation (P>0.05). CONCLUSION: Compared with PKP, bone setting manipulation combined with PVP for the treatment of OVCFs has advantages in early postoperative pain relief. In terms of vertebral height recovery, bone setting manipulation combined with PVP and PKP alone have similar clinical effects.

[A nomogram for predicting residual back pain after percutaneous vertebroplasty for osteoporotic vertebral compression fractures].

OBJECTIVE: To construct percutaneous vertebroplasty for predicting osteoporotic vertebral compression fractures (OVCFs) nomogram of residual back pain (RBP) after percutaneous vertebroplasty(PVP). METHODS: Clinical data of 245 OVCFs patients who were performed PVP from January 2020 to December 2022 were retrospectively analyzed, including 47 males and 198 females, aged from 65 to 77 years old with an average of (71.47±9.03) years old, and were divided into RBP group and non-RBP group according to whether RBP occurred. Gender, age, comorbidities, fracture stage, body mass index (BMI), bone mineral density (BMD), visual analogue scale (VAS), Oswestry disability index (ODI) and other general information were collected; anterior vertebral height (AVH), anterior vertebral height ratio (AVH), anterior vertebral height ratio(AVHR), Cobb angle, intravertebral vacuum cleft (IVC), thoracolumbar fascia (TLF) injury, paravertebral muscle steatosis, injection volume and leakage of bone cement, bone cement dispersion pattern, anterior vertebral height recovery ratio (AVHRR), Cobb angle changes, etc. imaging parameters before operation and 24 h after operation were collected. Univariate analysis was performed to analysis above factors, and multivariate Logistic regression model was used to investigate independent risk factors for postoperative RBP, and Nomogram model was constructed and verified;receiver operating characteristic(ROC) curve and calibration curve were used to determine predictive performance and accuracy of the model, and Hosmer-Lemeshow (H-L) test was used for evaluation. The area under curve (AUC) of ROC was calculated, and Harrell consistency index (C index) was used to evaluate the predictive efficiency of model;decision curve analysis (DCA) was used to evaluate clinical practicability of model. RESULTS: There were 34 patients in RBP group and 211 patients in non-RBP group. There were no significant differences in gender, age, comorbidities, fracture stage, BMI, BMD, VAS, ODI, AVH, AVHR and Cobb angle between two groups (P>0.05). Univariate analysis showed 6 patients occurred IVC in RBP group and 13 patients in non-RBP, the number of IVC in RBP group was higher than that in non-RBP group (χ2=5.400, P=0.020);6 patients occuured TLF injury in RBP group and 11 patients in non-RBP group, the number of TLF injury in RBP group was higher than that in non-RBP group (χ2=7.011, P=0.008);In RBP group, 18 patients with grade 3 to 4 paraptebral steatosis and 41 patients in non-RBP group, RBP group was higher than non-RBP group (χ2=21.618, P<0.001), and the proportion of bone cement mass in RBP group was higher than non-RBP group (χ2=6.836, P=0.009). Multivariate Logistic regression analysis showed IVC (χ2=4.974, P=0.025), TLF injury (χ2=5.231, P=0.023), Goutallier grade of paravertebral steatosis >2 (χ2=15.124, P<0.001) and proportion of bone cement (χ2=4.168, P=0.038) were independent risk factors for RBP after PVP. ROC curve of model showed AUC of original model was 0.816[OR=2.862, 95%CI (0.776, 0.894), P<0.001]. The internal verification of model through 200 bootstrap samples showed the value of C index was 0.936, and calibration curve showed predicted probability curve was close to actual probability curve. H-L goodness of fit test results were χ2=5.796, P=0.670. DCA analysis results showed the decision curve was above None line and All line when the threshold value ranged from 6% to 71%. CONCLUSION: IVC, TLF combined injury, paravertebral muscle steatosis with Goutallier grade> 2, and bone cement diffusion with mass type are independent risk factors for RBP after PVP. The risk prediction model for RBP after PVP established has good predictive performance and good clinical practicability.

Can We Rely on Prophylactic Two-Level Vertebral Cement Augmentation in Long-Segment Adult Spinal Deformity Surgery to Reduce the Incidence of Proximal Junctional Complications?

Background and Objectives: Proximal junctional kyphosis (PJK) and failure (PJF), the most prevalent complications following long-segment thoracolumbar fusions for adult spinal deformity (ASD), remain lacking in defined preventive measures. We studied whether one of the previously reported strategies with successful results-a prophylactic augmentation of the uppermost instrumented vertebra (UIV) and supra-adjacent vertebra to the UIV (UIV + 1) with polymethylmethacrylate (PMMA)-could also serve as a preventive measure of PJK/PJF in minimally invasive surgery (MIS). Materials and Methods: The study included 29 ASD patients who underwent a combination of minimally invasive lateral lumbar interbody fusion (MIS-LLIF) at L1-2 through L4-5, all-pedicle-screw instrumentation from the lower thoracic spine to the sacrum, S2-alar-iliac fixation, and two-level balloon-assisted PMMA vertebroplasty at the UIV and UIV + 1. Results: With a minimum 3-year follow-up, non-PJK/PJF group accounted for fifteen patients (52%), PJK for eight patients (28%), and PJF requiring surgical revision for six patients (21%). We had a total of seven patients with proximal junctional fracture, even though no patients showed implant/bone interface failure with screw pullout, probably through the effect of PMMA. In contrast to the PJK cohort, six PJF patients all had varying degrees of neurologic deficits from modified Frankel grade C to D3, which recovered to grades D3 and to grade D2 in three patients each, after a revision operation of proximal extension of instrumented fusion with or without neural decompression. None of the possible demographic and radiologic risk factors showed statistical differences between the non-PJK/PJF, PJK, and PJF groups. Conclusions: Compared with the traditional open surgical approach used in the previous studies with a positive result for the prophylactic two-level cement augmentation, the MIS procedures with substantial benefits to patients in terms of less access-related morbidity and less blood loss also provide a greater segmental stability, which, however, may have a negative effect on the development of PJK/PJF.

The Closer Vicinity to Treated Vertebrae in Percutaneous Vertebroplasty, the Higher Rate of New Vertebral Compression Fractures at Follow-up.

OBJECTIVE: To investigate whether risk of new vertebral compression fractures (NVCFs) was associated with vicinity to treated vertebrae in percutaneous vertebroplasty (PVP) for osteoporotic vertebral compression fractures (OVCFs). METHODS: All OVCF (T6-L5) patients treated with PVP between January 2016 and December 2020 were retrospectively reviewed. Vicinity to treated vertebrae was defined as the number of vertebrae between an untreated and its closest treated level. The closest treated level was chosen as reference vertebra. Clinical, radiologic, and surgical parameters were compared between groups of reference vertebrae for each vicinity NVCF. RESULTS: In total, 1348 patients with 1592 fractured and 14,584 normal vertebrae were enrolled. NVCF was identified in 20.1% (271 of 1348) patients in 2.2% (319 of 14584) vertebrae in a mean follow-up time of 24.3 ± 11.9 months. Rate of NVCF in vicinity 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, and 11 level were 4.6% (130 of 2808), 2.4% (62 of 2558), 1.8% (42 of 2365), 1.5% (31 of 2131), 1.3% (23 of 1739), 1.3% (17 of 1298), 0.8% (7 of 847), 0.9% (4 of 450), 0.8% (2 of 245), 0.9% (1 of 117), and 0% (0 of 26), respectively. Rate of NVCF in vicinity 1 level was significantly higher than that in vicinity 2, 3, 4, 5, 6, 7, 8, and 9 level, respectively. However, compared to reference vertebrae for vicinity 1 NVCF, any clinical, radiologic, or surgical parameters were not significantly different in those for vicinity 2, 3, and 4 NVCF, respectively. CONCLUSIONS: The closer vicinity to treated vertebrae in PVP, the higher rate of NVCF at follow-up. However, any clinical, radiologic, or surgical parameters might not matter in this phenomenon of vicinity-related NVCF.

Risk Factors of New Symptomatic Fractures After Vertebroplasty: A Retrospective Cohort Study of 268 Patients with Painful Osteoporotic Vertebral Compression Fracture.

OBJECTIVE: To evaluate the risk factors of new osteoporotic vertebral compression fractures (OVCFs) after percutaneous vertebroplasty (PVP). METHODS: From January 2016 to November 2019, patients suffering from OVCFs were retrospectively reviewed. The independent influence factors for new OVCFs after PVP were assessed, from following variables: age, sex, body mass index, bone mineral density (BMD), history of alcoholism, smoking, hypertension, diabetes, glucocorticoid use, and prior vertebral fractures, the number of initial fractures, mean cement volume, method of puncture, D-type of cement leakage, and regular antiosteoporosis treatment. RESULTS: A total of 268 patients with 347 levels met the inclusion criteria and were finally included in this study. Forty-nine levels of new OVCFs among 33 patients (12.31%) were observed during the follow-up period. It indicated that female (adjusted odds ratio [OR]: 6.812, 95% confidence interval {CI}: [1.096, 42.337], P = 0.040), lower BMD (adjusted OR: 0.477, 95% CI: [0.300, 0.759], P = 0.002), prior vertebral fractures (adjusted OR: 16.145, 95% CI: [5.319, 49.005], P = 0.000), and regular antiosteoporosis treatment (adjusted OR: 0.258, 95% CI: [0.086, 0.774], P = 0.016) were independent influence factors for new OVCF. The cut-off value of BMD to reach new OVCF was -3.350, with a sensitivity of 0.660 and a specificity of 0.848. CONCLUSION: Female, lower BMD (T-score of lumbar), prior vertebral fractures, and regular antiosteoporosis treatment were independent influencing factors. BMD (T-score of lumbar) lower than -3.350 would increase risk for new OVCF, and none osteoporotic treatment has detrimental effect on new onset fractures following PVP.

Space between bone cement and bony endplate can trigger higher incidence of augmented vertebral collapse: An in-silico study.

BACKGROUND: The pathogenesis of postoperative complications in patients with osteoporotic vertebral compressive fractures (OVCFs) undergoing percutaneous vertebroplasty (PVP) is multifaceted, with local biomechanical deterioration playing a pivotal role. Specifically, the disparity in stiffness between the bone cement and osteoporotic cancellous bone can precipitate interfacial stress concentrations, potentially leading to cement-augmented vertebral body collapse and clinical symptom recurrence. This study focuses on the biomechanical implications of the space between the bone cement and bony endplate (BEP), hypothesizing that this interface may be a critical locus for stress concentration and subsequent vertebral failure. METHODS: Leveraging a validated numerical model from our previous study, we examined the biomechanical impact of the cement-BEP interface in the L2 vertebral body post-PVP, simulated OVCF and PVP and constructed three distinct models: one with direct bone cement contact with both cranial and caudal BEPs, one with contact only with the caudal BEPs and one without contact with either BEP. Moreover, we assessed stress distribution across cranial and caudal BEPs under various loading conditions to describe the biomechanical outcomes associated with each model. RESULTS: A consistent trend was observed across all models: the interfaces between the bone cement and cancellous bone exhibited higher stress values under the majority of loading conditions compared to models with direct cement-BEP contact. The most significant difference was observed in the flexion loading condition compared to the mode with direct contact between BEP and cement. The maximum stress in models without direct contact increased by at least 30%. CONCLUSIONS: Our study reveals the biomechanical significance of interfacial stiffness differences at the cement-BEP junction, which can exacerbate local stress concentrations and predispose to augmented vertebral collapse. We recommend the strategic distribution of bone cement to encompass a broader contact area with the BEP for preventing biomechanical failure and subsequent vertebral collapse.

Clinical Observation and Cause Analysis of Perioperative Superior Cluneal Neuralgia in Vertebral Augmentation.

BACKGROUND: In our clinical practice, we observed that some osteoporotic vertebral compression fracture patients undergoing vertebral augmentation exhibited pain in the iliac crest region. This pain aligned with the diagnostic criteria for superior cluneal neuralgia (SCN) and affected treatment satisfaction. OBJECTIVE: This study aims to clinically observe patients undergoing vertebral augmentation in a hospital setting and analyze the etiology and risk factors associated with SCN. STUDY DESIGN: Retrospective cohort study. SETTING: Inpatient population of a single center. METHODS: We retrospectively analyzed clinical data from 630 patients who underwent vertebral augmentation in our hospital from March 2022 to March 2023. Fifty-two patients enrolled in the study experienced pain that met the diagnostic criteria for superior cluneal neuralgia during the perioperative period of the vertebral augmentation procedures. Those patients were divided into 2 subgroups according to the conditions involved in the occurrence of SCN: Group A (26 patients) had either no preoperative SCN but developed it postoperatively, or had preoperative SCN that worsened or did not alleviate postoperatively. Group B (26 patients) had preoperative SCN that was relieved postoperatively. Additionally, 52 consecutive patients in March 2022 to March 2023. who did not experience SCN during the perioperative period were selected as the control group (Group C). Variables such as surgical segment, age, height, weight, body mass index, duration of hospitalization, chronic low back pain (CLBP), duration of pain, anesthesia, surgical approach, fracture pattern, preoperative visual analog scale (pre-op VAS) score, intraoperative VAS score, one-day VAS score, one-month VAS score, lumbar sacral angle, and sacral tilt angle were statistically described and analyzed. RESULTS: In our hospital, the incidence of SCN during the perioperative period of vertebral augmentation procedures is 8.25% (52/630). Among all the segments of patients who developed SCN during the perioperative period, the L1 segment had the highest proportion, which was 29.03% and 35.14% in Groups A and B, respectively. Group B and Group C showed significant differences in duration of hospitalization (P = 0.012), pre-op VAS scores (P = 0.026), and CLBP (P < 0.001). Group A had significantly higher VAS scores preoperatively (P = 0.026) and intraoperatively (P = 0.004) and in CLBP (P = 0.001) than did Group C. LIMITATIONS: This is a retrospective study. Single-center noncontrolled studies may introduce selection bias. The small sample size in each group might have also led to bias. CONCLUSION: Perioperative SCN associated with vertebral augmentation is significantly correlated with preoperative VAS scores and CLBP. In addition, intraoperative VAS scores might be a factor contributing to the nonalleviation or exacerbation of postoperative SCN.

Predicting osteoporotic fractures post-vertebroplasty: a machine learning approach with a web-based calculator.

PURPOSE: The aim of this study was to develop and validate a machine learning (ML) model for predicting the risk of new osteoporotic vertebral compression fracture (OVCF) in patients who underwent percutaneous vertebroplasty (PVP) and to create a user-friendly web-based calculator for clinical use. METHODS: A retrospective analysis of patients undergoing percutaneous vertebroplasty: A retrospective analysis of patients treated with PVP between June 2016 and June 2018 at Liuzhou People's Hospital was performed. The independent variables of the model were screened using Boruta and modelled using 9 algorithms. Model performance was assessed using the area under the receiver operating characteristic curve (ROC_AUC), and clinical utility was assessed by clinical decision curve analysis (DCA). The best models were analysed for interpretability using SHapley Additive exPlanations (SHAP) and the models were deployed visually using a web calculator. RESULTS: Training and test groups were split using time. The SVM model performed best in both the training group tenfold cross-validation (CV) and validation group AUC, with an AUC of 0.77. DCA showed that the model was beneficial to patients in both the training and test sets. A network calculator developed based on the SHAP-based SVM model can be used for clinical risk assessment ( https://nicolazhang.shinyapps.io/refracture_shap/ ). CONCLUSIONS: The SVM-based ML model was effective in predicting the risk of new-onset OVCF after PVP, and the network calculator provides a practical tool for clinical decision-making. This study contributes to personalised care in spinal surgery.

Prediction of new vertebral compression fracture within 3 years after percutaneous vertebroplasty for osteoporotic vertebral compression fracture: Establishment and validation of a nomogram prediction model.

New vertebral compression fractures (NVCF) are common in patients with osteoporotic vertebral compression fractures (OVCF) who have undergone percutaneous vertebroplasty (PVP). We sought to develop a nomogram prediction model for better identification and prevention of NVCF within 3 years after PVP in patients with OVCF. The demographic, clinical, and imaging data of patients who underwent PVP for OVCF between January 2010 and December 2019 were reviewed. Multivariate logistic regression analysis was used to screen for risk factors for NVCF within 3 years after PVP. A nomogram prediction model was then developed and validated to visually predict NVCF. The samples in the model were randomly divided into training and validation sets at a ratio of 7:3. Twenty-seven percent of patients experienced NVCF in other segments within 3 years after PVP. Older age, lower bone mineral density (BMD), smoking, lack of anti-osteoporosis therapy, and postoperative trauma were risk factors for NVCF. The area under the receiver operating characteristic curve suggested good discrimination of this model: training set (0.781, 95% confidence interval: 0.731-0.831) and validation set (0.786, 95% confidence interval: 0.708-0.863). The calibration curve suggested good prediction accuracy between the actual and predicted probabilities in the training and validation sets. The DCA results suggested that, when the probability thresholds were 0.0452-08394 and 0.0336-0.7262 in the training and validation set, respectively, patients can benefit from using this model to predict NVCF within 3 years after PVP. In conclusion, this nomogram prediction model that included five risk factors (older age, lower BMD, smoking, postoperative minor trauma, and lack of anti-osteoporosis treatment can effectively predict NVCF within 3 years after PVP. Postoperative smoking cessation, standard anti-osteoporosis treatment, and reduction in incidental minor trauma are necessary and effective means of reducing the incidence of NVCF.

Percutaneous Vertebroplasty Versus Balloon Kyphoplasty in the Treatment of Osteoporotic Vertebral Compression Fractures: Evaluating the Overlapping Meta-analyses.

BACKGROUND: Numerous meta-analyses and systematic reviews have explored the differences between percutaneous vertebroplasty (PVP) and percutaneous balloon kyphoplasty (PKP) for treating osteoporotic vertebral compression fractures (OVCFs), however, their final conclusions have been inconsistent. The inconsistent conclusions drawn from these meta-analyses create uncertainty among clinicians about the best treatment approach for OVCFs. OBJECTIVE: The aim of this study was to conduct a cross-sectional analysis of overlapping meta-analyses comparing PVP and PKP treatments for OVCF in order to help clinicians have access to the best available evidence and provide treatment recommendations based on the best available evidence. STUDY DESIGN: A cross-sectional analysis of overlapping meta-analyses. METHODS: We conducted a comprehensive search of meta-analyses published up to February 2023 in PubMed, Embase, Cochrane Library and Web of Science databases to identify relevant studies. The methodological quality of these studies was assessed using the Assessment of Multiple Systematic Reviews tool (original AMSTAR) and the Oxford Centre for Evidence-based Medicine Levels of Evidence. Two researchers independently extracted the data and assessed the quality of these meta-analyses. To determine which meta-analyses represented the best evidence, we employed the Jadad decision algorithm. RESULTS: Seventeen meta-analyses were included in the study, with AMSTAR scores ranging from 4 to 9, with an average of 7. After rigorous scrutiny, the Zhu et al study was determined to provide the best evidence. According to their findings, both PVP and PKP effectively alleviate pain and improve function in the treatment of OVCFs, without any statistically significant differences between them. In addition, PKP can reduce the risk of polymethylmethacrylate leakage compared to PVP. LIMITATIONS: This study analyzed published overlapping meta-analyses, inherently confining our investigation to the meta-analysis level. Furthermore, based on the AMSTAR scores, several included studies exhibited lower methodological quality. CONCLUSIONS: Currently, the best evidence indicates that PVP and PKP are equally effective at alleviating pain and enhancing function in the treatment of OVCFs, but PKP had a lower incidence of polymethylmethacrylate leakage. However, there is still a need for high-quality randomized controlled trials to provide higher levels of evidence regarding other aspects of the differences between the 2 procedures.

Comparison Between Intraoperative Target Area Cement-Enhanced Percutaneous Vertebroplasty and Conventional Percutaneous Vertebroplasty for Osteoporotic Thoracolumbar Non-Total Vertebral Fractures.

AIM: To compare the efficacy and feasibility of target area cement-enhanced percutaneous vertebroplasty (PVP) and conventional PVP in osteoporotic thoracolumbar non-total vertebral fractures. MATERIAL AND METHODS: Retrospective analysis of one hundred and two patients treated in our hospital from March 2020 to May 2021 and divided into groups A (targeted) and B (conventional PVP). The Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), anterior vertebral height ratio, intraoperative bleeding, operative time, bone cement volume, complications, and refracture of the injured vertebra were evaluated in both groups. RESULTS: The 2 days and 1-year post-operative VAS and ODI scores improved significantly in both groups (p < 0.05). The 2 days post-operative VAS and ODI scores were better in group A (p < 0.05), and there was no significant difference in the scores between the groups at the last follow-up (p > 0.05). The anterior vertebral height ratios were significantly higher in both groups 2 days postoperatively (p < 0.05); however, there was no significant difference in the 2 days and 1-year post-operative ratios in group A (p > 0.05). The anterior vertebral height ratio reduced in group B after 1 year compared to the 2 days post-operative value (p < 0.05). There was no statistical difference in intraoperative bleeding and the operative time between the groups (p > 0.05), and the bone cement volume was lesser in group A (p < 0.05). Six patients in group A and four patients in group B demonstrated cement leakage, the difference was not statistically significant (p > 0.05). Three patients in group A and 11 patients in group B demonstrated refracture, the difference was statistically significant (p < 0.05). CONCLUSION: Target area cement-enhanced PVP can effectively relieve short-term pain and functional disability and reduce the long-term possibility of secondary collapse. Therefore, it is a technically feasible and efficacious method for the treatment of osteoporotic thoracolumbar non-total vertebral fractures.

[Development and clinical application of lateral segmental positioning plates of the body surface spine].

OBJECTIVE: To investigate the clinical efficacy of body-surface guide plates for lateral segmental positioning in the thoracolumbar spine. METHODS: From March 2018 to March 2021, 768 gerontal patientss underwent percutaneous vertebroplasty with balloon dilatation due to thoracolumbar compression fracturess, 356 males and 412 females. aged from 64 to 92 years old with an average of (77.9±13.5) years old. All patients were treated in hospital within 1 week after injury. All patients underwent preoperative localization, and were divided into localization plate group and locator group according to different localization methods. There were 390 patients in the localization plate group, 180 males and 210 females, aged from 64 to 92 years old, with an average age of (78.4±14.3) years old. There were 378 patients in the locator group, 176 males and 202 females, aged from 64 to 90 years old, with an average age of (77.5±13.4) years old. After preliminary positioning with the above two methods, skin markers were made, cloth was routinely disinfected, and the spinal lateral position was fluoroscopically examined after the fine needle was inserted into the marked point and the vertical body at the near tail end. The accuracy of the original positioning method was evaluated. The number of times, time and accuracy of positioning of the two groups of patients were compared and analyzed. RESULTS: The specific data of patient positioning in the two groups were collected for statistical analysis. The number of times of fluoroscopy in the positioning plate group and the locator group was(3.3±0.5) times and (5.0±1.2) times, and the positioning time was (60.4±9.4) s and (105.0±30.9) s, respectively. The accuracy of fluoroscopy was 97.5% (380/390) and 85.7% (324/378), respectively, with statistical significance (P<0.05). CONCLUSION: The lateral segmental positioning plate of the body surface spine has the advantages of simple operation, accurate positioning, and reducing X-ray radiation for patients, which is worthy of clinical application.

Microwave ablation combined with percutaneous vertebroplasty for treating painful non-small cell lung cancer with spinal metastases under real-time temperature monitoring.

PURPOSE: To retrospectively study the therapeutic effect and safety performance of the combination strategies of the computed tomography (CT)-guided microwave ablation (MWA) and percutaneous vertebroplasty (PVP) as a treatment for painful non-small cell lung cancer (NSCLC) with spinal metastases. MATERIALS AND METHODS: A retrospective review included 71 patients with 109 vertebral metastases who underwent microwave ablation combined with percutaneous vertebroplasty by the image-guided and real-time temperature monitoring. Treatment efficacy was determined by comparing visual analog scale (VAS) scores, daily morphine equivalent opioid consumption, and Oswestry Disability Index (ODI) scores before treatment and during the follow-up period. RESULTS: Technical success was achieved in all patients. The mean pre-procedure VAS score and morphine doses were 6.6 ± 1.8 (4-10) and 137.2 ± 38.7 (40-200) mg, respectively. The mean VAS scores and daily morphine doses at 24 h and 1, 4, 12, and 24 weeks postoperatively were 3.3 ± 1.9 and 73.5 ± 39.4 mg; 2.2 ± 1.5 and 40.2 ± 29.8 mg; 1.7 ± 1.2 and 31.3 ± 23.6 mg; 1.4 ± 1.1 and 27.3 ± 21.4 mg; and 1.3 ± 1.1 and 24.8 ± 21.0 mg, respectively (all P < 0.001). ODI scores significantly decreased (P < 0.05). Minor cement leakage occurred in 51 cases (46.8%), with one patient having a grade 3 neural injury. No local tumor progression was observed by follow-up imaging. CONCLUSIONS: MWA combined with PVP can significantly relieve pain and improve patients' quality of life, which implied this is an effective treatment option for painful NSCLC with spinal metastases. Additionally, its efficacy should be further verified through the mid- and long-term studies.

Safety and clinical efficacy of microwave ablation combined with percutaneous vertebroplasty in the treatment of multisegmental spinal metastases.

OBJECTIVE: To evaluate the safety and efficacy of microwave ablation (MWA) combined with percutaneous vertebroplasty (PVP) in the treatment of multisegmental (2-3 segments) osteolytic spinal metastases. MATERIALS AND METHODS: This study comprised a retrospective analysis of data from 20 patients with multisegmental (2-3 segments) osteolytic spinal metastases who received MWA combined with PVP. The visual analog scale (VAS) score, Oswestry Disability Index (ODI) score, Quality of Life Questionnaire-Bone Metastases 22 (QLQ-BM22), and local recurrence before and after the operation were measured. The occurrence of complications was observed to evaluate safety. RESULTS: All operations were completed successfully with no serious complications. Transient nerve injury occurred in two cases, but recovered after symptomatic treatment. The bone cement leakage rate was 13.9% (6/43). The mean baseline VAS scores were 7.25 ± 0.91 before treatment and 7.25 ± 0.91, 3.70 ± 1.12, 2.70 ± 0.73, 2.40 ± 0.68, 2.25 ± 0.71, and 2.70 ± 0.92 at 1 day, 1 week, 1, 3, and 6 months after treatment; all values were significantly lower (P < 0.001). The mean baseline ODI score decreased from 56.90 ± 9.74 before treatment to 41.90 ± 7.09, 38.10 ± 7.93, and 38.80 ± 10.59 at 1, 3, and 6 months after treatment, respectively; all values were significantly lower (P < 0.001). The average QLQ-BM22 baseline score decreased from 54.10 ± 5.36 before treatment to 44.65 ± 5.22, 43.05 ± 4.78, 42.30 ± 4.06, and 42.15 ± 5.47 at 1 week, 1, 3, and 6 months after treatment; all values were significantly lower (all P < 0.001). The postoperative survival time of all patients was >6 months. In three patients, four vertebral segments recurred 6 months after operation. CONCLUSION: MWA combined with PVP is a safe and effective treatment for multisegmental osteolytic vertebral metastases that can effectively relieve pain, improve spinal function, improve quality of life, and delay tumor progression. However, it is a long operation, necessitating good preoperative preparation and effective intraoperative pain relief measures.