Pulmonary Cement Embolism after Percutaneous Vertebroplasty in Osteoporotic Vertebral Compression Fractures: Incidence, Characteristics, and Risk Factors

Incidence of Cement Leakage and Potential Risk Factors in Surgery for Spinal Metastasis: A Systematic Review and Meta-Analysis

OBJECTIVES

The current meta-analysis was performed to gather available evidence regarding the incidence and risk factors of cement leakage (CL) in patients undergoing surgical procedures for spinal metastasis.

METHODS

Two authors independently searched the PubMed, Embase, and CENTRAL databases. Clinical studies reporting the incidence or risk factors of CL were included for analysis. The primary outcome analyzed was the incidence of various types of CL. Random-effects or fixed-effects single-proportion meta-analyses were conducted to pool the available evidence, based on the heterogeneity test. Subgroup analyses were conducted based on surgical procedures (percutaneous vertebroplasty, percutaneous kyphoplasty, and others). Risk factors of CL were synthesized narratively to identify the most commonly accepted factors.

RESULTS

A total of 26 studies, involving 2551 patients, were included. The number of operated spine segments was reported in 23 studies, accounting for 4101 vertebrae. The pooled incidences of general, intradiscal, paravertebral, spinal canal, and intravascular CLs were 0.18 (95% confidence interval [CI], 0.11-0.28), 0.14 (95% CI, 0.08-0.21), 0.13 (95% CI, 0.06-0.21), 0.11 (95% CI, 0.05-0.19), and 0.12 (95% CI, 0.08-0.17), respectively. Subgroup analyses revealed significantly different incidences of general CL (0.37 vs. 0.06 vs. 0.09, P < 0.01), intradiscal CL (0.22 vs. 0.06 vs. 0.12, P < 0.01), paravertebral CL (0.25 vs. 0.03 vs. 0.06, P < 0.01), and vascular CL (0.14 vs. 0.03 vs. 0.15, P < 0.01) among the three groups. Posterior wall disruption, pathologic fracture, and the number of treated vertebral levels were the most commonly identified independent risk factors for general CL. Posterior wall disruption was determined as a common significant risk factor for spinal canal CL.

CONCLUSIONS

This review provides insights into the incidence and risk factors associated with CL in surgical procedures for spinal metastasis. Understanding these risk factors can contribute to the development of tailored strategies aimed at minimizing CL occurrence and optimizing surgical outcomes for patients undergoing spinal metastatic surgery.

Evaluation of multidetector CT Hounsfield unit measurements as a predictor of efficacy and complications in percutaneous vertebroplasty for osteoporotic vertebral compression fractures

Introduction

More than 30 years after the initial experience of Galibert and Deramond with percutaneous vertebroplasty, the procedure has gone through countless refinements and clinical evaluations. Predictors for the success and failure of the procedure in the literature vary and are focused on the duration of complaints, type of fracture, presence of edema on MRI scans, etc. We propose using a quantitative method based on a standard CT examination of the thoracic or lumbar spine to assess the risks and potential success of performing vertebroplasty.

Materials and methods

This is a single-center prospective observational study on 139 patients treated with percutaneous vertebroplasty (pVPL) for a single symptomatic osteoporotic vertebral compression fracture (OVCF). We measured the levels of disability and pain preoperatively and again at the 3-, 6- and 12-month marks using the standardized VAS and ODI questionnaires. Every patient in the study was evaluated with postoperative multidetector CT (MDCT) to determine the presence, extent, and localization of vertebral cement leakage and to measure the adjacent vertebrae's minimal and mean density in Hounsfield units (HUmin and HUmean, respectively).

Results

We determined that a slight (r = -0.201) but statistically significant (p = 0.018) correlation existed between HU measurements taken from radiologically intact adjacent vertebrae and the procedure's effect concerning the pain levels at the 3-month follow-up. This correlation failed to reach statistical significance at 12 months (p = 0.072). We found no statistically significant relationship between low vertebral cancellous bone density and cement leakage on postoperative scans (p = 0.6 for HUmin and p = 0.74 for HUmean).

Conclusion

We have moderately strong data that show a negative correlation between the mean values of vertebral cancellous bone density in patients with OVCF and the effect of pVPL in reducing pain. Lower bone densities, measured this way, showed no increased risk of cement leakage.

[Osteoporotic vertebral body fractures]

The number of osteoporotic fractures of the spine is increasing. These fractures are associated with elevated morbidity and mortality. This article provides an overview of the special features of these fractures, the diagnostic procedure, their classification, and the conservative and surgical treatment options. For the mostly elderly patients, it is important to treat the underlying disease and to address associated problems such as frailty and sarcopenia. To meet this growing medical and socio-economic challenge, a holistic interdisciplinary and interprofessional treatment approach is required.

Similarities and Differences in the Management of Patients with Osteoporotic Vertebral Fractures and Those with Rebound-Associated Vertebral Fractures Following Discontinuation of Denosumab

Rebound-associated vertebral fractures (RVFx) following denosumab discontinuation are typically multiple, are commonly associated with acute sharp pain, increase the risk of imminent fractures, and are pathogenetically different from common osteoporotic vertebral fractures (VFx). A clinically relevant question is whether patients with RVFx should be managed differently from patients with osteoporotic VFx. To address this question, we performed a systematic search of the PubMed database, and we reviewed current evidence on the optimal management of patients with RVFx. For pain relief of patients with RVFx, potent analgesics, often opioids, are essential. Information on the effectiveness of braces in these patients is scarce. Vertebroplasty and kyphoplasty are strongly contraindicated as they confer a substantial risk for new VFx. Exercise may be helpful, but again evidence is lacking. In contrast to patients with osteoporotic VFx, in whom initial treatment with bone-forming agents is recommended, patients with RVFx should initiate treatment with potent antiresorptives. To summarize, patients who have sustained RVFx following denosumab discontinuation are at a very high risk for new fractures, especially VFx. The management of such patients requires a multidisciplinary approach that should not be restricted to pain relief and administration of antiosteoporotic medication, but should also include back protection, early mobilization, and appropriate exercise.

Case report: Open-heart removal for a cement embolism formed 10 years ago in the right ventricle and pulmonary artery

Bone cement embolism is a known complication after a kyphoplasty operation. Cement embolisms without immediate fatal complication such as cardiac perforation or hypoxemia were often stable during observation. We report a case of a large volume bone cement embolism involving the right ventricle and the pulmonary artery system. The patient developed mild exertional shortness of breath and chest pain after a percutaneous kyphoplasty (PKP) operation 10 years ago. However, her mild symptoms were attributed to multiple myeloma, and no chest imaging was taken until the symptoms exacerbated after a COVID-19 infection 6 months ago. A large, tree-branch-shaped embolus was found, causing severe obstruction of the ascending and middle-lobe branch of the right pulmonary artery. The pulmonary perfusion scintigraphy demonstrated an impaired perfusion of the right upper and middle lobe. An open-heart removal was performed, and the symptoms were relieved afterward. We report this case to highlight the importance of routine chest imaging after a PKP operation and to claim that open-heart removal for chronic cement pulmonary embolism is technically feasible and safe.

The significance of the best puncture side bone cement/vertebral volume ratio to prevent paravertebral vein leakage of bone cement during vertebroplasty: a retrospective study

OBJECTIVES

To verify the clinical significance of the best puncture-side bone cement/vertebral volume ratio (PSBCV/VV%) and bone cement leakage in paravertebral veins during vertebroplasty.

METHODS

This was a retrospective analysis of a total of 210 patients from September 2021 to December 2022, who were divided into an observation group (110 patients) and a control group (100 patients). In the observation group, patients' preoperative computed tomography (CT) data were imported into Mimics software, and the VV was calculated using the three-dimensional (3D) reconstruction function. Then, based on the best PSBCV/VV% of 13.68% determined in a previous study, the optimal PSBCV to be injected during vertebroplasty was calculated. In the control group, vertebroplasty was performed directly using the conventional method. The incidence of cement leakage into paravertebral veins was observed postoperatively in both groups.

RESULTS

There were no statistically significant differences (P > 0.05) in the evaluated indicators between the two groups pre- or postoperatively, including the anterior vertebral margin height, mid-vertebral height, injured vertebral Cobb angle, visual analogue scale (VAS) score, and Oswestry Disability Index (ODI). Intragroup comparisons showed improvements in the anterior vertebral height, mid-vertebral height, injured vertebral Cobb angle, VAS score, and ODI after surgery compared with before surgery (P < 0.05). In the observation group, there were 3 cases of cement leakage into the paravertebral veins, for a leakage rate of 2.7%. In the control group, there were 11 cases of cement leakage into the paravertebral veins, for a leakage rate of 11%. The difference in the leakage rate between the two groups was statistically significant (P = 0.016).

CONCLUSION

In vertebroplasty, preoperative VV calculations using Mimics software, combined with calculation of the PSBCV according to the best PSBCV/VV% (13.68%), can effectively prevent leakage of bone cement into paravertebral veins and further prevent serious life-threatening complications such as pulmonary embolism.

Comparison of unipedicular and bipedicular kyphoplasty for treating acute osteoporotic vertebral compression fractures in the lower lumbar spine: a retrospective study

BACKGROUND

Unipedicular and bipedicular approaches for percutaneous kyphoplasty are reportedly both effective in treating osteoporotic vertebral compression fractures (OVCFs). However, most studies have reported thoracolumbar fractures, with few reports describing the treatment of the lower lumbar spine. Here, we compared the clinical and radiological results of unipedicular and bipedicular approaches for percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures.

METHODS

We retrospectively reviewed the records of 160 patients who underwent percutaneous kyphoplasty for lower lumbar (L3-L5) osteoporotic vertebral compression fractures between January 2016 and January 2020. Patient characteristics, surgical outcomes, operation time, blood loss, clinical and radiological features, and complications were compared between two groups. Cement leakage, height restoration, and cement distribution were calculated from the radiographs. Visual pain analog scale (VAS) and Oswestry Disability Index (ODI) were calculated before surgery, immediately post-surgery, and 2 years after surgery.

RESULTS

The mean age, sex, body mass index, injury time, segmental distribution, and morphological classification of fractures before surgery did not differ significantly between the groups. The results showed significant improvements in the VAS score, ODI score, and vertebral height restoration in each group (p < 0.05), with no significant differences between the two groups (p > 0.05). The mean operation time and extent of blood loss were lower in the unipedicular group than those in the bipedicular group (p < 0.05). Different types of bone cement leakage were observed in both groups. Leakage rate was higher in the bipedicular group than in the unipedicular group. Patients in the bipedicular group showed greater improvement in bone cement distribution than those in the unipedicular group (p < 0.05).

CONCLUSIONS

The clinical and radiological results of unipedicular percutaneous kyphoplasty for treating osteoporotic vertebral compression fractures in the lower lumbar region were similar to those of bipedicular percutaneous kyphoplasty. However, the unipedicular approach resulted in shorter surgical time, less blood loss, and less bone cement leakage. Thus, the unipedicular approach may be preferable owing to its several advantages.

Balloon kyphoplasty versus percutaneous vertebroplasty for osteoporotic vertebral body compression fractures: clinical and radiological outcomes

BACKGROUND CONTEXT

Osteoporotic vertebral body compression fracture are the commonest fractures amongst the other osteoporotic fracture sites. These fragility fractures are the result of low energy mechanical forces that that would not ordinarily result in fracture. Percutaneous vertebroplasty and balloon kyphoplasty has been widely used as minimally invasive procedures to treat painful vertebral compression fractures.

PURPOSE

Aim of the present study was to evaluate radiological, clinical and functional outcome of patients with osteoporotic vertebral body fractures treated with Balloon Kyphoplasty and Vertebroplasty.

STUDY DESIGN

Prospective cohort study PATIENT SAMPLE: 40 patients (Male:15, Female: 25) with average age of 56 +/- 8 years diagnosed with osteoporotic vertebral body compression fracture on clinical and radiological evaluation with no neurological deficit and no other associated fractures were included.

OUTCOME MEASURES

Operative time, cost for the procedure, gain in vertebral body height, reduction in pain, ability to perform daily routine activities, risk of cement leakage and any other systemic complications were evaluated and compared in both the study groups.

METHODS

All the patients underwent conventional Xray, MRI (to rule out acute from chronic fracture, to check compromise of spinal canal and calculate collapse in vertebral body height), Visual analog scaling for severity of pain and difficulty in daily routine activities by Oswestry disability index preoperatively. Post operative clinal, functional, radiological outcome and complications were compared in patients treated with percutaneous vertebroplasty and balloon kyphoplasty.

RESULT

There was significant difference in intraoperative time period and procedure cost for the patients treated with Vertebroplasty(50.75min, 25k) in comparison to balloon kyphoplasty (71.95, 50k) with p value being < .001 There was significant difference between preoperative and postoperative study parameters in both the study groups but there was no significant difference in post operative study parameters amongst both the study groups with p values >.05 for different parameters, 0.381(Gain in vertebral height), 0.108 (pain relief), 0.846(Oswestry disability index) and 0.197(risk of cement leakage) CONCLUSION: Our study suggested that percutaneous vertebroplasty requires less operative time and is more economical than balloon kyphoplasty. Increase in intraoperative time increases the risk of infection. Though the cases of Intraoperative operative cement leakage were more in percutaneous vertebroplasty but is was not significant. However the final radiological, clinical, functional outcome and overall complications were found to be similar in both the groups. Balloon kyphoplasty provided no added benefit over percutaneous vertebroplasty. A study with larger sample size will be needed to warrant one surgical procedure superior to other in the treatment of osteoporotic vertebral body compression fracture.

Percutaneous Ablation, Osteoplasty, Reinforcement, and Internal Fixation for Pain and Ambulatory Function in Periacetabular Osteolytic Malignancies

Background Osteolytic neoplasms to periacetabular bone frequently cause pain and fractures. Immediate recovery is integral to lifesaving ambulatory oncologic care and maintaining quality of life. Yet, open acetabular reconstructive surgeries are associated with numerous complications that delay cancer treatments. Purpose To determine the effectiveness for short- and long-term pain and ambulatory function following percutaneous ablation, osteoplasty, reinforcement, and internal fixation (AORIF) for periacetabular osteolytic neoplasm. Materials and Methods This retrospective observational study evaluated clinical data from 50 patients (mean age, 65 years ± 14 [SD]; 25 men, 25 women) with osteolytic periacetabular metastases or myeloma. The primary outcome of combined pain and ambulatory function index score (range, 1 [bedbound] through 10 [normal ambulation]) was assessed before and after AORIF at 2 weeks and then every 3 months up to 40 months (overall median follow-up, 11 months [IQR, 4-14 months]). Secondary outcomes included Eastern Cooperative Oncology Group (ECOG) score, infection, transfusion, 30-day readmission, mortality, and conversion hip arthroplasty. Serial radiographs and CT images were obtained to assess the hip joint integrity. The paired t test or Wilcoxon signed-rank test and Kaplan-Meier analysis were used to analyze data. Results Mean combined pain and ambulatory function index scores improved from 4.5 ± 2.4 to 7.8 ± 2.1 (P < .001) and median ECOG scores from 3 (IQR, 2-4) to 1 (IQR, 1-2) (P < .001) at the first 2 weeks after AORIF. Of 22 nonambulatory patients, 19 became ambulatory on their first post-AORIF visit. Pain and functional improvement were retained beyond 1 year, up to 40 months after AORIF in surviving patients. No hardware failures, surgical site infections, readmissions, or delays in care were identified following AORIF. Of 12 patients with protrusio acetabuli, one patient required a conversion hemiarthroplasty at 24 months. Conclusion The ablation, osteoplasty, reinforcement, and internal fixation, or AORIF, technique was effective for short- and long-term improvement of pain and ambulatory function in patients with periacetabular osteolytic neoplasm. © RSNA, 2023.

Biodegradable Cements for Bone Regeneration

Bone cements such as polymethyl methacrylate and calcium phosphates have been widely used for the reconstruction of bone. Despite their remarkable clinical success, the low degradation rate of these materials hampers a broader clinical use. Matching the degradation rate of the materials with neo bone formation remains a challenge for bone-repairing materials. Moreover, questions such as the mechanism of degradation and how the composition of the materials contribute to the degradation property remain unanswered. Therefore, the review provides an overview of currently used biodegradable bone cements such as calcium phosphates (CaP), calcium sulfates and organic-inorganic composites. The possible degradation mechanism and clinical performance of the biodegradable cements are summarized. This paper reviews up-to-date research and applications of biodegradable cements, hoping to provide researchers in the field with inspirations and references.

Cardiopulmonary Cement Embolism Following Cement-Augmented Pedicle Screw Fixation: A Narrative Review

Fixation using cement-augmented pedicle screws (CAPS) is being increasingly performed. However, CAPS-associated cement leakage is a critical problem that can lead to cardiopulmonary cement embolism (CPCE). This narrative review aimed to explore the incidence of and risk factors and treatment strategies for CPCE and cement leakage-related complications after CAPS fixation. Data were extracted from each article, including characteristics of CPCE after CAPS fixation (incidence, location, diagnostic method and criteria, treatment, and outcome and prognosis). Overall, 28 case series and 14 case reports that met the inclusion criteria were included. Of the 1974 cases included in the review, CPCE was noted in 123, symptomatic CPCE in 35, and death in six, respectively. The frequencies of PCE and symptomatic PCE after CAPS fixation were 6% (range: 0-28.6%) and 1.3% (range: 0-26%), respectively. The range of frequencies of PCE and symptomatic PCE after CAPS fixation may have been wide because the definition of CPCE and data collection methods differed among the reports analyzed. Since PCE due to large cement emboli may be primarily related to the surgical technique, improved technique, such as minimizing the number of CAPSs by injecting low-volume high-viscosity cement at low velocity and pressure, and careful observation of cement leakage during CAPS insertion may reduce PCE associated with cement leakage. Spinal surgeons should pay more attention to the occurrence of CPCE during and after CAPS insertion, which can cause serious complications in some patients.

Risk factors for pulmonary cement embolism after percutaneous vertebroplasty and radiofrequency ablation for spinal metastases

Objective

Pulmonary cement embolism is a rare but underestimated complication of vertebroplasty due to the relative lack of study and examination. This study aims to investigate the incidence of pulmonary cement embolism in patients with spinal metastasis who undergo PVP with RFA and to analyze the relative risk factors.

Methods

A total of 47 patients were retrospectively included and classified into pulmonary cement embolism (PCE) group and non-pulmonary cement embolism (NPCE) group by comparing pre- and postoperative pulmonary CT scan images. The demographic and clinical information of the patients was obtained. Demographic data in the two groups were compared using the chi-square test for qualitative data and the unpaired t test for quantitative data. Multiple logistic regression analysis was used to identify risk factors related to pulmonary cement embolism.

Results

Pulmonary cement embolism was detected in 11 patients (23.4%), and all patients were asymptomatic and followed up regularly. Risk analysis showed that multiple segments (≥3, p=0.022), thoracic vertebrae (p=0.0008), and unipedicular puncture approach (p=0.0059) were risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra (p<0.0001). Vein leakage of cement was related to the integrity of the vertebral cortex.

Conclusion

The number of involved vertebrae, lesion location, and puncture approach are independent risk factors for pulmonary cement embolism. There was a high incidence of pulmonary cement embolism if bone cement leaked into the para vertebral venous plexus in the thoracic vertebra. Surgeons should consider these factors when formulating therapeutic strategies.

Venous injection of a triphasic calcium-based implant in a sheep model of pulmonary embolism demonstrates minimal acute systemic effects

PURPOSE

Implant leakage is the most common complication of vertebral augmentation. Alternative injectable materials must demonstrate intravascular safety comparable to or better than polymethyl methacrylate (PMMA). This study assessed the systemic effects of a triphasic calcium-based implant or PMMA injected directly into the femoral vein in a large animal model designed to mimic severe intravascular implant leakage.

METHODS

Six skeletally mature female sheep were randomly assigned (n = 3) to either the PMMA or the triphasic implant (AGN1, composition: calcium sulfate, β-tricalcium phosphate, brushite) treatment group. Femoral veins of each sheep were directly injected with 0.5 mL of implant material to mimic leakage volumes reported during PMMA vertebroplasty. To compare acute systemic effects of the materials, cardiovascular parameters, laboratory coagulation markers, and calcium and sulfate serum levels were monitored for 60 min after implant injection. Thrombotic and embolic events were evaluated by radiologic imaging, necropsy, and histopathology.

RESULTS

Heart rate, systemic arterial blood pressure, arterial oxygenation, arterial carbon dioxide content, and coagulation markers remained within physiological range after either AGN1 or PMMA injection. No blood flow interruption in the larger pulmonary vessels was observed in either group. Lung histopathology revealed that the severity of thrombotic changes after AGN1 injection was minimal to slight, while changes after PMMA injection were minimal to massive.

CONCLUSION

Acute systemic effects of intravascular AGN1 appeared to be comparable to or less than that of intravascular PMMA. Furthermore, in this preliminary study, the severity and incidence of pulmonary histological changes were lower for AGN1 compared to PMMA.

Case report: Cement entrapped in the inferior vena cava filter after pedicle screw augmentation

Background

Cement leakage into the inferior vena cava (IVC) is one of the most common complications associated with cement vertebroplasty, and can lead to potentially life-threatening complications such as pulmonary cement embolism (PCE). Implantation of an IVC filter is effective in the prevention of fatal pulmonary embolism. Here, we present an extremely rarely case of cement entrapped in an IVC filter after pedicle screw augmentation, and discuss all similar cases reported in the literature.

Case presentation

A 70-year-old female presented with significant back and lower extremities pain and was unable to walk. MRI of the lumbar spine revealed an osteoporotic compression fracture of the L1–L3. She underwent cement-augmented pedicle screws implanted at the L1 and L3 vertebral bodies. A retrievable IVC filter was implanted due to the presence of calf vein thrombosis before cement vertebroplasty. Cement leaked into the IVC and was trapped by the filter, rendering the filter unretrievable using a conventional method. The asymptomatic patient received rivaroxaban 20 mg daily for anticoagulant postoperatively and lifelong anticoagulation was administered to prevent secondary IVC and cemented filter thrombosis.

Methods

A literature search was conducted utilizing the PUBMED/MEDLINE using the following terms: “vertebroplasty,” “complication,” “bone cement,” and “inferior vena cava (IVC),” or “inferior vena cava (IVC) filter.” All relevant articles published in English or in other languages with English abstracts since 1962 were included.

Results

A total of 36 articles were retrieved according to the search strategy. Only 6 out of these 36 studies contained information regarding the inferior vena cava filter and cement. Of the patients, 85.7% (36/42) reported in the literature whose gender was known were female and 14.3% were male. 28.5% (45/158) patients with pulmonary arterial and cardiovascular complications.

Conclusion

Cement embolization occurring in the IVC filter is rare. Accurate knowledge about the lumbar vertebral venous anatomy and skillful operation during vertebral cementoplasty should be required in clinical practice.

Vertebroplasty in geriatric patients with osteoporotic vertebral fractures: single-center cohort study at a level 1 center for spinal surgery

Study design

Retrospective single-center cohort study.

Background

The spine is the most common anatomic site for osteoporotic fractures. Osteoporotic vertebral fractures play an increasingly important role in geriatric patients and percutaneous vertebroplasty (PVP) constitutes a common treatment option. The aim of this study was to evaluate the safety and efficacy of PVP in geriatric patients with cardiovascular comorbidities at our center.

Methods

In this retrospective single-center study, 49 patients aged ≥ 65 with a total of 88 vertebral fractures underwent vertebroplasty. MRI and CT scans of the spine were performed in all patients prior to surgery. All patients were evaluated 4 weeks after surgery as part of their clinical follow-up. VAS scores were recorded before and after the operation. Postoperative complications within 30 days of the initial surgery were analyzed.

Results

The mean age of patients was 77 years (± 6.4). Of the 49 patients, 39 (80%) were female, and 36 (76%) had cardiovascular comorbidities. The most frequent postoperative complications were cement leakage with no new neurological postoperative deficits (14.3%). The in-hospital mortality rate was 1 out of 49 patients (2%). VAS scores revealed an overall pain reduction of > 97%. None of the following affected patient safety: ASA, BMI, duration of surgery, or the level or localization of vertebroplasty.

Conclusions

Our data demonstrate that vertebroplasty was a feasible and effective treatment for pain reduction in geriatric patients with osteoporotic fractures despite cardiovascular comorbidities.

Level of evidence

3.

Massive cardiopulmonary cement embolism with cardiac perforation after vertebroplasty: a case series

Background

The prevalence of cement embolism after percutaneous vertebroplasty ranges from 2.1 to 26%, in literature. Even if most cases remain asymptomatic, intracardiac cement embolism becomes symptomatic in up to 8.3% of the cases.

Case summary

We report a case series of two cases with massive cardiopulmonary cement embolism, which lead to perforation of the right ventricle and needed cardiothoracic surgery.

Discussion

As this entity affects different fields of medical specialties and may lead to fatal outcome, we believe that the efforts of better understanding its development, avoidance, detection, and treatment need to be intensified. For this purpose, systematic and interdisciplinary studies to follow up patients after vertebroplasty are needed.

Analysis of the most influential publications on vertebral augmentation for treating osteoporotic vertebral compression fracture: A review

This study aimed to analyze the most influential publications on vertebral augmentation for treating osteoporotic vertebral compression fracture. The Web of Science database was searched using the key words "percutaneous vertebroplasty," "percutaneous kyphoplasty," "balloon kyphoplasty," "vertebroplasty," "kyphoplasty," and "vertebral augmentation." The top 100 publications were arranged by citations per year and descriptively and visually analyzed. The top 100 publications were cited 25,482 times, with an average of 14.4 citations per paper per year. The corresponding authors of the publications represented 17 nations, with most authors being American (46 authors). Thirty-two journals were involved, with SPINE issuing the most publications (24 papers of the 100). Clinical research (73 of the 100 papers) outnumbered basic studies (14 papers) and systematic reviews (13 papers), and the most publications were published between 2000 and 2004. Co-citation analysis of the key words indicated that the top 5 focus areas were "complication," "balloon kyphoplasty," "vertebral compression fracture," "biomechanics," and "calcium phosphate cement." The top 3 keywords with the strongest citation bursts were "compression fracture," "cement," and "balloon kyphoplasty." The keywords with persistent strong citation bursts are "balloon kyphoplasty" and "augmentation." There are still contrary opinions about vertebral augmentation; new research should be conducted with more deliberate design and longer follow-up.

Radiofrequency Ablation and Augmentation in the Management of Spinal Metastases: Clinical Experience in 41 Patients

OBJECTIVE

To evaluate functional outcome after combined radiofrequency ablation and vertebral augmentation in patients with metastatic spinal tumors using visual analog scale and Oswestry Disability Index scores.

METHODS

This retrospective study included 41 patients with metastatic spinal tumors. There were 19 women and 22 men with a mean age of 67 years (range, 45-87 years). Visual analog scale and Oswestry Disability Index were used to assess the intensity of pain and quality of life. The assessments were performed before the procedure and at 1 week and 1, 2, 3, and 6 months after the procedure.

RESULTS

No serious complications were seen in the periprocedural period. Two patients (4.8%) had transient neurological motor deficits without cement leakage, and 1 patient had a pulmonary embolism with transient mild symptoms. The comparison of preprocedural visual analog scale and Oswestry Disability Index scores with postprocedural scores up to 6 months after treatment revealed significant pain control and good functional state.

CONCLUSIONS

Spinal metastasis is a frequent entity in the growing population of patients with cancer. A multidisciplinary approach using several nonsurgical and minimally invasive methods (e.g., radiofrequency ablation, vertebroplasty, balloon kyphoplasty) is key to successful management, and combining these procedures is effective against spinal metastatic pain.

The role of percutaneous vertebral augmentation in patients with metastatic breast cancer: Literature review including report of two cases

Patients with metastatic breast cancer are at high risk for developing vertebral compression fractures due to underlying bone metastases and bone density loss. Vertebral augmentation techniques including percutaneous vertebroplasty and percutaneous balloon kyphoplasty are techniques used to stabilize compression fractures and improve pain. However, rare complications from these interventions have been observed, including spinal cord compression, nerve root compression, venous cement embolism, and pulmonary cement embolism. These complications pose unique potential challenges for patients with cancer who may already have decreased lung function and potential for venous thromboembolism. In this review, we first describe the role of percutaneous vertebral augmentations in patients with metastatic cancer, with a particular focus on patients with breast cancer. Then, we describe complications of vertebral augmentation in two patients with metastatic breast cancer including long-term symptomatic and radiographic follow-up.

•

Balloon kyphoplasty and percutaneous vertebroplasty are used to stabilize compression fractures and improve pain.

•

Leakage of bone cement can cause cement emboli which can depsit in locations such as the pulmonary and renal vasculature.

•

Management of cement emboli depends on the amount of cement embolized and the severity of symptoms.

•

Future studies are needed to better understand the long-term radiographic and clinical consequences of cement emboli.

Life-threatening intracardiac cement embolisms after percutaneous kyphoplasty: a case report and literature review

BACKGROUND

Percutaneous kyphoplasty is a popular technique in the treatment of osteoporotic vertebral fractures, but intracardiac cement embolism can be a life-threatening complication.Case presentation: The authors present a case involving a patient who developed dyspnea and chest tightness after percutaneous kyphoplasty. Echocardiography and chest computed tomography confirmed several foreign bodies in the right atrium and pulmonary arteries causing cardiac perforation and pericardial tamponade. Conservative treatment was administered, and the patient died of respiratory and heart failure.

CONCLUSIONS

The present case highlights that surgical removal may be the first-choice treatment for symptomatic intracardiac cement embolism.

Risk factors for pulmonary cement embolism associated with percutaneous vertebral augmentation: A systematic review and meta-analysis

BACKGROUND

Pulmonary cement embolism (PCE) was a rare but fatal complication for percutaneous vertebral augmentation (PVA). Thus we did a systematic review and meta-analysis of cohort studies to investigate the risk factors for PCE after PVA.

METHODS

We systematically searched PubMed, EMBASE, Cochrane library, Google Scholar, web of science, and ClinicalTrial.gov from the establishment of the database to September 2021. All eligible studies assessing the risk factors for PCE after PVA were incorporated. Dichotomous data was calculated by risk difference (RD) from Mantel-Haenszel method (M - H method); continuous data was analyzed by mean difference (MD) from Inverse-Variance method (I-V method). All variables were taken as measure of effect by fixed effect model. Heterogeneity, sensitivity, and publication bias analyses were also performed.

RESULTS

This study totally included 13 studies. According to the Newcastle-Ottawa Scale (NOS), 7 studies were considered as low quality, with NOS< 6. The others were of relatively high quality, with NOS≥6. 144/6251 patients (2.3%) had PCE after PVA. percutaneous vertebroplasty (PVP) (RD = 0.02, 95%CI: [0.01, 0.04], Z = 3.70, P < 0.01), thoracic vertebra (RD = 0.03, 95%CI: [0.01, 0.05], Z = 3.53, P < 0.01), higher cement volume injected per level (MD = 0.23, 95%CI: [0.05, 0.42], Z = 2.44, P = 0.01), more than three vertebrae treated per session (MD = -0.05, 95%CI: [-0.08, -0.02], Z = 3.65, P < 0.01), venous cement leakage (RD = 0.07, 95%CI: [0.03, 0.11], Z = 3.79, P < 0.01) were more likely to cause PCE.

CONCLUSION

This study showed that risk factors for PCE included PVP, thoracic vertebra, higher cement volume injected per level, more than three vertebrae treated per session, venous cement leakage. As a serious complication, PCE should be paid attention and avoided.

Percutaneous Cement-Augmented Screws Short Fixation for the treatment of Severe Osteoporotic Vertebral Burst Fractures

OBJECTIVE (BACKGROUND)

This study aims to evaluate the therapeutic reliability of posterior percutaneous cement-augmented screws short fixation(PASF) in patients with severe osteoporotic vertebral burst fractures(OVBFs).

METHODS

Single-level OVBFs with an anterior vertebral body height(VBH) reduction equal or superior to 60% were included. A frailty index was employed for preoperative frailty assessment. Back pain and related disability were assessed through the VAS scale and Oswestry low-back pain disability index(ODI), being administered at injury time, preoperative, postoperative, twelfth-month and last patient follow-up evaluations. The main radiological outcomes were represented by Cobb angle(CA) and anterior vertebral body compression percentage(AVBC%), being measured at injury time, preoperative, postoperative and twelfth-month examinations. Among the others, the incidence of cement leakages and hardware failures was assessed.

RESULTS

Thirty-three patients met the inclusion criteria. All patients resulted frail(76%) or semi-frail(24%). Significant VBH restoration and segmental kyphosis improvement after PASF was documented (AVBC%:-40(-43;-37) VS -67(-70;-65), P = 0.0001; CA: 10(8-12) VS 24(23-26), P = 0.0001). The mean VAS and ODI scores documented optimal and long-enduring pain relief and related disability reduction after PASF (VAS: 2(2-3) VS 8(7-8), P = 0.0001; ODI: 22(17-26) VS 64(60-69), P = 0.0001). Only one cement leakage (3%), asymptomatic, occurred. After a mean follow-up of 33 months, no early/late hardware failures were reported.

CONCLUSIONS

The clinical and radiological results of this study suggest that PASF could be a safe and effective treatment option for severe OVBFs when conservative treatments failed.

Pulmonary cement embolism is frequently observed but not a contributing factor for death in patients with cemented total hip and knee arthroplasty: a postmortem study

Purpose

Bone cement is frequently used for implant fixation in orthopaedic surgery. The occurrence of pulmonary cement embolism (PCE) in hip and knee arthroplasty has been described previously, but the exact extent and frequency have not been adequately studied. A postmortem cohort provides a unique opportunity for a more detailed analysis of this phenomenon.

Methods

Through retrospective analysis of whole-body computed tomography (CT) scans and autopsy protocols, we identified 67 cases with previous cemented total hip or knee arthroplasties. A grading system originally developed for PCE after cemented spine procedures was used. Findings were compared with two control groups: 35 individuals with previous cementless total joint arthroplasty as well as 25 individuals without evidence of prostheses.

Results

PCE was detected in 46.3% of the cases: grade 1 (31.3%), grade 2 (10.5%), and grade 3 (4.5%). No statistically significant difference was found between hip and knee arthroplasties in terms of PCE frequency. Importantly, none of the autopsy reports listed PCE as a cause of death or a contributing factor for the patients’ death. In the two control groups, only one case per group was classified as grade 1 PCE, while the remaining cases did not show any evidence of PCE.

Conclusion

The presented data reveal a high frequency of PCE in hip and knee arthroplasties, which is almost identical to previous findings in patients with cement-augmented interventions in the spine. This way, our results underline the relevance of PCE after arthroplasty, suggesting an adaptation of surgical methods to minimize this complication.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00264-022-05381-6.

The combination of radiofrequency ablation and vertebroplasty shows advantages over single vertebroplasty in treating vertebral neoplastic lesions

OBJECTIVE

To investigate the safety and efficacy of the combination of radiofrequency ablation (RFA) and vertebroplasty versus single vertebroplasty in treating spinal metastases.

MATERIALS AND METHODS

The data of 35 patients with vertebral neoplastic lesions who received RFA combined with vertebroplasty (group A, 15 patients with 17 lesions) or single vertebroplasty (group B, 20 patients with 24 lesions) from March 2016 to June 2019 were retrospectively compared. The data of patients' Visual Analogue Scale (VAS) scores prior to the treatments, 1 week, 1 month, 3 months, and 6 months after the treatments, injected cement volume, ratios of cement leakage were compared between the two groups.

RESULTS

All procedures were successfully done without severe complications. The VAS scores in group A were decreased more rapidly 1 week after the treatments and remained more stable at 6 months than that in group B (P < 0.05). The cement injected in group A (5.95 ± 1.45 mL, range 4-9.5 mL) was significantly more than that in group B (4.09 ± 0.55 mL, range 3.1-5.5 mL) (P < 0.05). The ratio of vascular cement leakage in group A was significantly lower than that in group B (P < 0.05), while no statistical difference was found in the non-vascular cement leakage (P > 0.05).

CONCLUSIONS

Our study shows that the combination of RFA and vertebroplasty has a better analgesic effect with more injected cement and lower rates of venous cement leakage than single vertebroplasty.

Percutaneous Kyphoplasty Versus Percutaneous Vertebroplasty for Neurologically Intact Osteoporotic Kümmell's Disease: A Systematic Review and Meta-Analysis

STUDY DESIGN

Systematic review and meta-analysis.

OBJECTIVE

Percutaneous vertebroplasty (PVP) and percutaneous kyphoplasty (PKP) are minimally invasive techniques widely used for the treatment of neurologically intact osteoporotic Kümmell's disease (KD), but which treatment is preferable remains controversial. Therefore, this study aimed to shed light on this issue.

METHODS

Six databases were searched for all relevant studies based on the PRISMA guidelines. Two investigators independently conducted a quality assessment, extracted the data and performed all statistical analyses.

RESULTS

Eight studies encompassing 438 neurologically intact osteoporotic KD patients met the inclusion criteria. Compared to PVP, PKP was associated with greater improvement in the short- and long-term Cobb angle [SMD = -0.37, P = 0.007; SMD = -0.34, P = 0.012], short-term anterior vertebral height [SMD = 0.43, P = 0.003] and long-term middle vertebral height [SMD = 0.57, P = 0.012] and a lower cement leakage rate [SMD = 0.50, P = 0.003] but produced more consumption (cement injection volume, operative time, fluoroscopy times, intraoperative blood loss and operation cost). However, there were no differences between the 2 procedures in the short- and long-term VAS and ODI scores, long-term anterior vertebral height, overall complications or new vertebral fractures.

CONCLUSIONS

Both procedures are equally effective for neurologically intact KD in terms of the clinical outcomes, with the exception of a lower cement leakage risk and better radiographic improvement for PKP but greater resource consumption. Based on the evidence available, good clinical judgment should be exercised in the selection of patients for these procedures.

Correlation analysis of the puncture-side bone cement/vertebral body volume ratio and bone cement leakage in the paravertebral vein in vertebroplasty

Objectives

To explore the influencing factors of bone cement leakage in the paravertebral vein after vertebroplasty for the treatment of osteoporotic vertebral compression fractures (OVCFs) and to determine the correlation between the puncture-side bone cement/vertebral body volume ratio and bone cement leakage in the paravertebral vein.

Methods

This was a retrospective analysis of 495 patients (585 vertebral bodies) with OVCFs treated from August 2018 to May 2021 in our hospital. The patients’ postoperative CT data were imported into Mimics software, and the three-dimensional(3D) reconstruction function was used to calculate the bone cement volume (BCV), puncture-side bone cement volume (PSBCV), and vertebral body volume (VBV); the bone cement/vertebral body volume ratio (BCV/VCV%) and puncture-side bone cement/vertebral body volume ratio (PSBCV/VCV%) were additionally calculated. Sex, Age, Body mass index(BMI), Bone density, BCV, PSBCV, VBV, BCV/VCV%, and PSBCV/VCV were compared between the leakage group and the non-leakage group. Logistic regression analysis was used to assess the correlations between the factors that statistically significantly differed between the two groups and the presence of leakage in the paravertebral veins. A receiver operating characteristic (ROC) curve was used to determine the diagnostic value of the PSBCV/VCV% and to obtain the optional cut-off value.

Results

A total of 102 males and 393 females with an average age of 72.89 (52 ~ 93) years were included in our study. There were 57 cases of cement leakage (59 vertebral bodies) in the paravertebral vein. There were 438 patients (526 vertebral bodies) without paravertebral cement leakage. Univariate analysis showed that the differences in sex, bone density, PSBCV, and PSBCV/VCV% between the two groups were statistically significant (P < 0.05). Logistic regression analysis showed that there were correlations between sex, bone density, and PSBCV/VCV% and the presence of paravertebral cement leakage (P < 0.05). The ROC curve showed that the area under the curve of the PSBCV/VCV% for the diagnosis of cement leakage in the paravertebral vein was greater than 0.65, and P < 0.05, indicating a diagnostic value. The best cut-off point for the diagnosis of paravertebral cement leakage with the PSBCV/VCV% was 13.68%, with a sensitivity of 84.7% and specificity of 37.8%.

Conclusion

Sex, bone density, and PSBCV/VCV% are risk factors for cement leakage in the paravertebral veins after vertebroplasty for the treatment of OVCFs; the PSBCV/VCV% is strongly associated with paravertebral venous leakage, and the optimal PSBCV/VCV% is 13.68%. When the PSBCV/VCV% exceeds the optimal value, the risk of cement leakage in the paravertebral vein becomes significantly increased.

Risk Factors for Pulmonary Cement Embolism (PCE) After Polymethylmethacrylate Augmentation: Analysis of 32 PCE Cases

Objective

Pulmonary cement embolism (PCE) is an underestimated but potentially fatal complication after cement augmentation. Although the treatment and follow-up of PCE have been reported in the literature, the risk factors for PCE are so far less investigated. This study aims to identify the preoperative and intraoperative risk factors for the development of PCE.

Methods

A total of 1,373 patients treated with the polymethylmethacrylate (PMMA) augmentation technique were retrospectively included. Patients with PCE were divided into vertebral augmentation group and screw augmentation group. Possible risk factors were collected as follows: age, sex, bone mineral density, body mass index, diagnosis, comorbidity, surgical procedure, type of screw, augmented level, number of augmented vertebrae, fracture severity, presence of intravertebral cleft, cement volume, marked leakage in the paravertebral venous plexus, and periods of surgery. Binary logistic regression analyses were used to analyze independent risk factors for PCE.

Results

PCE was identified in 32 patients, with an incidence rate of 2.33% (32 of 1,373). For patients who had undergone vertebral augmentation, marked leakage in the paravertebral venous plexus (odds ratio [OR], 1.2; 95% confidence interval [CI], 0.1–10.3; p=0.000) and previous surgery (OR, 16.1; 95% CI, 4.2–61.0; p=0.007) were independent risk factors for PCE. Regarding patients who had undergone screw augmentation, the marked leakage in the paravertebral venous plexus (OR, 4.2; 95% CI, 0.5–37.3; p=0.004) was the main risk factor.

Conclusion

Marked leakage in the paravertebral venous plexus and previous surgery were significant risk factors related to PCE. Paravertebral leakage and operator experience should be concerned when performing PMMA augmentation.

Risk factors for predicting cement leakage in percutaneous vertebroplasty for spinal metastases

BACKGROUND

The study aimed to identify the risk factors of cement leakage following percutaneous vertebroplasty for spinal metastases.

METHODS

230 consecutive patients with 530 vertebrae were retrospectively reviewed. Characteristics including age, primary cancer, location, pathological fracture, the integrity of the posterior wall, and the volume of bone cement were considered as potential risk factors. Cement leakage was evaluated by postoperative imaging examination and classified into three subtypes with different potential sequelae: spinal canal leakage, intravascular leakage around vertebrae, intradiscal and paravertebral leakage. Univariate and multivariate analyses were used to assess the risk factors.

RESULTS

Leakage was detected in 185 vertebrae (34.9%), 18.3% for intradiscal and paravertebral, 13.2% for intravascular around vertebrae, and 7.0% for spinal canal. Multivariate analysis showed that incomplete posterior wall (P = 0.001) and breast cancer (P = 0.015) were strong predictive factors for spinal canal leakage, incomplete posterior wall (P = 0.024) was for intravascular leakage around vertebrae, thoracic (P = 0.010) and pathological fracture (P = 0.000) were for intradiscal and paravertebral leakage.

CONCLUSIONS

Our findings suggest that cement leakage is common following percutaneous vertebroplasty for spinal metastases. The incomplete posterior wall is an unfavourable factor for intravascular leakage around vertebrae. Vertebrae with incomplete posterior wall and breast cancer metastases are more likely to develop spinal canal leakage.

A Nomogram to Predict Intra-Spinal Canal Cement Leakage Among Elderly Patients with Spine Metastases: An Internal-Validated Model

Purpose

This study aimed to assess the risk variables for predicting intra-spinal canal cement leakage, especially among elderly patients with spine metastases after being treated with percutaneous vertebroplasty (PVP). Furthermore, we proposed and validated a nomogram to stratify risks of intra-spinal canal cement leakage.

Methods

We retrospectively analyzed 163 elderly patients (age ≧65 years) with spine metastases who underwent PVP. Patients were randomly divided into a training cohort (n=100) and a validation cohort (n=63). The multivariate logistic regression analysis was used to screen potential risk variables in the training cohort. Significant risk variables were included in the nomogram, and the nomogram was developed according to the estimates of the each included variable. The predictive effectiveness of the nomogram was validated using discrimination and calibration performance.

Results

The overall prevalence of intra-spinal canal cement leakage was 9.82% (16/163). In the training cohort, female patients (14.71%, 5/34) showed a higher rate of intra-spinal canal cement leakage as compared with male patients (4.55%, 3/66). The nomogram consisted of sex, cortical osteolytic destruction in posterior wall, and load-bearing lines of spine. The nomogram had acceptable discrimination, with the area under the receiver operating characteristic (AUROC) of 0.75 in the training cohort, 0.64 in the validation cohort, and 0.69 in the entire cohort, and also showed favorable calibration based on the goodness-of-fit test. According to the nomogram, three risk groups were developed: the low risk group had an actual probability of 7.03%, the medium risk group was 11.54%, and high risk group was 44.44%. The difference between the three groups was significant (P ˂ 0.01).

Conclusion

Intra-spinal canal cement leakage after PVP is not scarce among elderly patients. We proposed and internally validated a nomogram that is capable of calculating the risk of intra-spinal canal cement leakage among elderly patients with spine metastases. Careful surgical plan should be conducted among patients with a high risk of developing intra-spinal canal cement leakage.

Experimental examination of radiation doses from cardiac and liver CT perfusion in a phantom study as a function of organ, age and sex

Cardiac and liver computed tomography (CT) perfusion has not been routinely implemented in the clinic and requires high radiation doses. The purpose of this study is to examine the radiation exposure and technical settings for cardiac and liver CT perfusion scans at different CT scanners. Two cardiac and three liver CT perfusion protocols were examined with the N1 LUNGMAN phantom at three multi-slice CT scanners: a single-source (I) and second- (II) and third-generation (III) dual-source CT scanners. Radiation doses were reported for the CT dose index (CTDI_vol) and dose-length product (DLP) and a standardised DLP (DLP_10cm) for cardiac and liver perfusion. The effective dose (ED_10cm) for a standardised scan length of 10 cm was estimated using conversion factors based on the International Commission on Radiological Protection (ICRP) 110 phantoms and tissue-weighting factors from ICRP 103. The proposed total lifetime attributable risk of developing cancer was determined as a function of organ, age and sex for adults. Radiation exposure for CTDI_vol, DLP/DLP_{10 cm}and ED_{10 cm}during CT perfusion was distributed as follows: for cardiac perfusion (II) 144 mGy, 1036 mGy·cm/1440 mGy·cm and 39 mSv, and (III) 28 mGy, 295 mGy·cm/279 mGy·cm and 8 mSv; for liver perfusion (I) 225 mGy, 3360 mGy·cm/2249 mGy·cm and 54 mSv, (II) 94 mGy, 1451 mGy·cm/937 mGy·cm and 22 mSv, and (III) 74 mGy, 1096 mGy·cm/739 mGy·cm and 18 mSv. The third-generation dual-source CT scanner applied the lowest doses. Proposed total lifetime attributable risk increased with decreasing age. Even though CT perfusion is a high-dose examination, we observed that new-generation CT scanners could achieve lower doses. There is a strong impact of organ, age and sex on lifetime attributable risk. Further investigations of the feasibility of these perfusion scans are required for clinical implementation.

Catheter-Induced Cement Embolism During Attempted Ablation Procedure

Pulmonary cement embolism is a well-described complication of cement vertebroplasty (1,2). We describe the case of a patient with acute cement embolism during catheter insertion for attempted pulmonary vein isolation 1 month after cement vertebroplasty. We discuss the mechanism of acute cement embolism, possible sequelae, and treatment considerations. (Level of Difficulty: Intermediate.)

Safety and efficacy studies of kyphoplasty, mesh-container-plasty, and pedicle screw fixation plus vertebroplasty for thoracolumbar osteoporotic vertebral burst fractures

Background

Percutaneous kyphoplasty (PKP), percutaneous mesh-container-plasty (PMCP), and pedicle screw fixation plus vertebroplasty (PSFV) were three methods for osteoporotic vertebral burst fractures (OVBF). The purpose of the current study was to evaluate the clinical safety and efficacy of PKP, PMCP, and PSFV for OVBFs.

Methods

This retrospective study included 338 consecutive patients with thoracolumbar OVBFs who underwent PKP (n = 111), PMCP (n = 109), or PSFV (n = 118) and compared their epidemiological data, surgical outcomes, and clinical and radiological features. Clinical evaluations of VAS and ODI and radiological evaluations of height restoration, deformity correction, cement leakage, and canal compromise were calculated preoperatively, postoperatively, and 2 years postoperatively.

Results

Cement leakage (31/111 vs. 13/109 and 16/118, P < 0.05) was significantly higher in group PKP than in groups PSFV and PMCP. VAS and ODI scores improved postoperatively from 7.04 ± 1.15 and 67.11 ± 13.49 to 2.27 ± 1.04 and 22.00 ± 11.20, respectively, in group PKP (P < 0.05); from 7.04 ± 1.29 and 67.26 ± 12.79 to 2.17 ± 0.98 and 21.01 ± 7.90, respectively, in group PMCP (P < 0.05); and from 7.10 ± 1.37 and 67.36 ± 13.11 to 3.19 ± 1.06 and 33.81 ± 8.81, respectively, in the PSFV group (P < 0.05). Moreover, postoperative VAS and ODI scores were significantly higher in group PSFV than in groups PKP and PMCP (P < 0.05). However, VAS scores were not significantly different in the three groups 2 years postoperatively (P > 0.05). Postoperative anterior (81.04 ± 10.18% and 87.51 ± 8.94% vs. 93.46 ± 6.42%, P < 0.05) and middle vertebral body height ratio (83.01 ± 10.16% and 87.79 ± 11.62% vs. 92.38 ± 6.00%, P < 0.05) were significantly higher in group PSFV than in groups PMCP and PKP. Postoperatively, Cobb angle (10.04 ± 4.26° and 8.16 ± 5.76° vs. 4.97 ± 4.60°, P < 0.05) and canal compromise (20.76 ± 6.32 and 19.85 ± 6.18 vs. 10.18 ± 6.99, P < 0.05) were significantly lower in group PSFV than in groups PMCP and PKP.

Conclusion

Despite relatively worse radiological results, PMCP is a safe and minimally invasive surgical method that can obtain better short-term clinical results than PKP and PSFV for OVBFs.

Prediction of early vascular cement leakage following percutaneous vertebroplasty in spine metastases: the Peking University First Hospital Score (PUFHS)

BACKGROUND

Cement leakage into venous blood posed significant challenge to surgeons. The aim of the study was to create a Peking University First Hospital Score (PUFHS) which could evaluate the probability of vascular cement leakage among spine metastases patients following percutaneous vertebroplasty.

METHODS

The study retrospectively enrolled 272 spine metastases patients treated with percutaneous vertebroplasty. We randomly extracted all enrolled patients as the training or validation group and baseline characteristic comparison was assessed between the two groups. Creation of the PUFHS was performed in the training group and validation of the PUFHS was performed in the validation group.

RESULTS

Of all the 272 patients, the total number of included vertebrae was 632 and the median treated levels were 2 per patient. Vascular cement leakage occurred in 26.47% (72/272) of patients. The baseline characteristics were comparable between the two groups (P > 0.05). Three risk predictors (primary cancer types, number of treated vertebrae levels, and vertebrae collapse) were included in the PUFHS. The area under the receiver operating characteristic curve (AUROC) of the PUFHS was 0.71 in the training group and 0.69 in the validation group. The corresponding correct classification rates were 73.0 and 70.1%, respectively. The calibration slope was 0.78 (95% confidence interval[CI]: 0.45-1.10) in the training group and 1.10 (95% CI: 0.73-1.46) in the validation group. The corresponding intercepts were 0.06 (95% CI: - 0.04-0.17) and - 0.0079 (95% CI: - 0.11-0.092), respectively.

CONCLUSIONS

Vascular cement leakage is common among spine metastases after percutaneous vertebroplasty. The PUFHS can calculate the probability of vascular cement leakage, which can be a useful tool to inform surgeons about vascular cement leakage risk in advance.

Radiologic mimics of pulmonary embolism

The diagnosis of pulmonary embolism (PE) is often made more challenging by the presence of diseases that can mimic thromboembolic disease. There is no specific or sensitive constellation of clinical signs or symptoms that can be used to diagnose PE. Ventilation/perfusion scans can have false-positive findings related to mediastinal conditions that can compress the pulmonary arteries, and pulmonary hemorrhage can resemble PE on V/Q scanning with potentially devastating consequences if anticoagulation is started. CT-scan related issues l eading to potential false-positive diagnoses range from inadequate imaging technique, to systemic-pulmonary shunting, to non-thrombotic occlusion of pulmonary arteries by tumor, septic emboli, and emboli of fat, air, and foreign material, as well as vasculitic processes. Careful assessment of the patient and consideration of these potential mimickers is imperative to correct diagnosis of this potentially life-threatening condition.

Refracture of the cemented vertebrae after percutaneous vertebroplasty: risk factors and imaging findings

BACKGROUND

To determine the related imaging findings and risk factors to refracture of the cemented vertebrae after percutaneous vertebroplasty (PVP) treatment.

METHODS

Patients who were treated with PVP for single vertebral compression fractures (VCFs) and met this study's inclusion criteria were retrospectively reviewed from January 2012 to January 2019. The follow-up period was at least 2 years. Forty-eight patients with refracture of the cemented vertebrae and 45 non-refractured patients were included. The following variates were reviewed: age, sex, fracture location, bone mineral density (BMD), intravertebral cleft (IVC), kyphotic angle (KA), wedge angle, endplate cortical disruption, cement volume, surgical approach, non-PMMA-endplate-contact (NPEC), cement leakage, other vertebral fractures, reduction rate (RR), and reduction angle (RA). Multiple logistic regression modeling was used to identify the independent risk factors of refracture.

RESULTS

Refracture was found in 48 (51.6%) patients. Four risk factors, including IVC (P = 0.005), endplate cortical disruption (P = 0.037), larger RR (P = 0.007), and NPEC (P = 0.006) were found to be significant independent risk factors for refracture.

CONCLUSIONS

Patients with IVC or larger RR, NPEC, or endplate cortical disruption have a high risk of refracture in the cemented vertebrae after PVP.

Epidemiology and detection of cement leakage in patients with spine metastases treated with percutaneous vertebroplasty: A 10-year observational study

•

Cement leak is common for percutaneous vertebroplasty in metastatic spinal disease.

•

A proposed and validated algorithm can screen patients with high cement leak risk.

•

The algorithm included four significant characteristics.

•

The validation group AUROC was 0.69, and the goodness-of-fit test P-value was 0.50.

Objectives

To investigate the epidemiology of cement leaks and further develop an algorithm to detect the high risk of cement leaks among advanced cancer patients with metastatic spinal disease treated with percutaneous vertebroplasty.

Methods

This study retrospectively analyzed 309 patients with metastatic spinal disease treated with percutaneous vertebroplasty. Patients were randomly divided into a training group and a validation group. In the training group, 13 potential characteristics were analyzed for their abilities to predict cement leaks. Discal cement leakage and paravertebral cement leakage were excluded from the analysis. Those characteristics identified as having significant predictive value were used to develop a predictive algorithm. Internal validation of the algorithm was performed based on discrimination and calibration qualities.

Results

Overall, cement leaks occurred in 61.17% (189/309) patients. Among the 13 characteristics analyzed, younger age (P = 0.03), extravertebral bone metastases (P = 0.02), increased number of treated vertebrae levels (P < 0.01), and cortical osteolytic destruction in the posterior wall (P = 0.01) were included in the algorithm. This algorithm generates a score between 0 and 16 points, with higher scores indicating a higher risk of cement leakage. The area under the receiver operating characteristic curve (AUROC) value for the algorithm was 0.75 in the training group and 0.69 in the validation group. The mean correct classification rates for the training and validation groups were 73.5% and 64.9%, respectively, and the corresponding P-values of the goodness-of-fit test were 0.70 and 0.50.

Conclusions

Cement leaks are common in patients with metastatic spinal disease treated with percutaneous vertebroplasty. The present study proposed and internally validated an algorithm that can be used to screen patients at high risk of cement leakage.

Diagnosis of pulmonary cement embolism using only the bone window setting on computed tomography: a case report

Pulmonary cement embolism (PCE) is one of several complications of percutaneous vertebroplasty and kyphoplasty. Generally, PCE can be easily diagnosed based on typical chest radiograph findings such as single or multiple radiographically dense opacities with a tubular or branch shape in the lung field along with a recent history of percutaneous vertebroplasty or kyphoplasty. These findings can be alarming and may be encountered on routine chest radiographs, even in asymptomatic patients. One study showed that PCEs that were not visualized on chest radiograph were also not shown on chest computed tomography. However, we encountered a patient with dyspnea who had normal chest radiograph findings but was diagnosed with PCE through only the bone window setting on chest computed tomography. The present case will be beneficial to all physicians examining older patients with dyspnea.

Basivertebral foramina of true vertebrae: morphometry, topography and clinical considerations

PURPOSE

Basivertebral foramina (BVF) are openings of the posterior wall of vertebral body (VB) that lead to basivertebral canals (BVC), where homonymous neurovascular bundle courses. BVF and BVC are implicated with spinal fractures, vertebral augmentation and basivertebral nerve radiofrequency ablation. Despite their essential clinical impact, knowledge of BVF precise anatomy is scarce. The current study describes in detail the BVF typical morphological and topographical anatomy, morphometry and variants.

METHODS

In total, 1561 dried true vertebrae of 70 Greek spines of known gender and age were examined. BVF number, location, shape and size (in foramina > 1 mm), BVF distance from VB rims and pedicles, as well as VB morphometry (diameters, heights and distance between pedicles) were studied. Ten spines were re-examined by computed tomography and BVC depth and shape were recorded. Correlations and differences were statistically analyzed.

RESULTS

C₁ lack BVF (3.4%). One BVF was found in 45.1%, two in 36.9%, three in 3.8% and four BVF in 0.6%. Multiple small (< 1 mm) foramina were observed in 10.1%. Asymmetry was detected in 12.3%. C₂ and T₁₀-L₁ presented typical pattern, whereas C₃ and T₂ had the greatest variability. BVF were significantly closer to the upper rim in C₂ and T₁₀-L₄ and to the lower rim in C₇-T₄, T₆-T₈ and L₅. The mean BVC depth was 12-21.8% of the VB anteroposterior diameter.

CONCLUSION

BVF number, shape, size and topography are described, in detail, per vertebral level. The provided morphological classification and the created cumulative BVF topographic graphs should assist in clinical practice and surgery.

Resolution of Pulmonary Cement Embolism After Treatment of Rivaroxaban on Ventilation/Perfusion SPECT Image

ABSTRACT

A 73-year-old woman took a chest radiography for medical check-up, and pulmonary cement embolism was diagnosed. She had undergone percutaneous vertebroplasty. Ventilation-perfusion imaging revealed V/Q mismatched perfusion defect on the lung. Then, she has taken rivaroxaban (orally active direct factor Xa inhibitor) for 6 months and took follow-up V/Q scan. It revealed the disappearance of previous 2 of 3 moderate V/Q mismatches. There are controversies in the role of anticoagulation in treatment of pulmonary cement embolism, and this case shows functional recovery through the perfusion scan after anticoagulation treatment.

The impact of incidental pulmonary cement embolism on mortality risk

The prognosis of pulmonary cement embolism found incidentally on chest radiography after vertebroplasty has been rarely investigated. This study was performed to elucidate the impact of incidentally found pulmonary cement embolism on all-cause mortality. Patients with pulmonary cement embolism diagnosed using chest radiography between 2008 and 2014 at one tertiary referral hospital were included. Their mortality risk was compared to that of randomly selected, age-, sex-, and year-matched patients without pulmonary cement embolism (ratio, 1:10) by using Kaplan-Meier estimates and covariate-adjusted Cox proportional regression analysis. The study included 11 patients with pulmonary cement embolism and 110 patients without pulmonary cement embolism. The patients showed no significant intergroup differences in baseline characteristics, except comorbid heart failure. During a mean follow-up duration of 1.7 ± 1.6 years, five patients (45.5%) with pulmonary cement embolism and 60 (50.0%) without pulmonary cement embolism died, mostly because of underlying malignancy. Although the patients with pulmonary cement embolism were not treated, they did not show a higher mortality risk than did those without pulmonary cement embolism (adjusted hazard ratio, 1.10; 95% confidence interval, 0.43-2.85). Subgroup analyses showed similar results. Incidentally found pulmonary cement embolism had no significant impact on all-cause mortality.

Percutaneous mesh-container-plasty for osteoporotic thoracolumbar burst fractures: A prospective, nonrandomized comparative study

OBJECTIVE

This study aimed to compare the clinical and radiological results of percutaneous mesh-container-plasty (PMCP) versus percutaneous kyphoplasty (PKP) in the treatment of osteoporotic thoracolumbar burst fractures.

METHODS

A prospective study of 122 patients with osteoporotic thoracolumbar burst fractures was conducted. The patients were nonrandomly assigned to receive PKP (62; 16 men, 46 women) and PMCP (60; 14 men, 46 women). The epidemiological data, surgical outcomes, and clinical and radiological features were compared between the 2 groups. Cement leakage, height restoration, deformity correction, canal compromise, and cement distribution were calculated from the radiographs. Visual pain analog scale (VAS), the Oswestry disability index (ODI), and short-form 36 health survey domains role physical (SF-36 rp) and bodily pain (SF-36 bp) were calculated before surgery and immediately and 2 years after surgery.

RESULTS

Although VAS, ODI, SF-36 bp, and SF-36 rp scores improved from 7 (6-9), 71.28±16.38, 22 (0-32), and 25 (0-50) preoperatively to 2 (1-3), 20.02±8.97, 84 (84-84), and 75 (75-100) immediately postoperatively in the PMCP group (p<0.05) and from 7 (6-8), 71.40±13.52, 22 (10.5-31.75), and 25 (0-50) preoperatively to 2 (1-3), 21.78±11.21, 84 (84-84), and 75 (75-100) immediately postoperatively in the PKP group (p<0.05), there was no difference between the 2 groups. The mean cost in the PKP group was less than that in the PMCP group ($5109±231 vs. $6699±201, p<0.05). Anterior, middle, and posterior vertebral body height ratios in the PMCP group were greater than those in the PKP group postoperatively (88.44%±3.76% vs. 81.10%±11.78%, 86.15%±3.50% vs. 82.30%±11.02%, and 93.91%±3.01% vs. 91.43%±6.71%, respectively, p<0.05). The Cobb angle in the PMCP group was lower than that in the PKP group postoperatively (6.67°±4.39° vs. 8.99°±4.06°, p<0.05). Cement distribution in the PMCP group was higher than that in the PKP group (30.48%±5.62% vs. 27.18%±4.87%, p<0.05). Cement leakage was observed to be lesser in the PMCP group (2/60) than in the PKP group (10 vs. 62, p<0.05).

CONCLUSION

Both PKP and PMCP treatments seem to have significant ability in pain relief and functional recovery. Despite its higher cost, PMCP treatment may have a better inhibition ability of cement leakage, cement distribution, height restoration, and improvement in segmental kyphosis than PKP treatment for osteoporotic thoracolumbar burst fractures.

LEVEL OF EVIDENCE

Level II, Therapeutic Study.