Pulmonary Palacos embolism: a case report

Asymptomatic Intracardiac Cement Embolism Following Kyphoplasty

Cement extravasation can occur during vertebral body augmentation such as kyphoplasty and vertebroplasty with diverse presentation and resultant treatment. The cement can embolize through venous vasculature to the thorax where it poses a potential threat to the cardiovascular and pulmonary systems. A thorough risk-benefit analysis should be conducted to select the appropriate treatment course. We present an asymptomatic case of cement extravasation to the heart and lungs during kyphoplasty.

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.

Pulmonary cement embolism following transpedicular screws placement for thoracolumbar fractures

Background

Symptomatic pulmonary cement embolism in patients undergoing thoracic transpedicular fenestrated screw placement is rare. Here, we have added a 64-year-old female undergoing transpedicular screw placement for a T11 fracture who developed a pulmonary cement embolism intraoperatively and add this case to 13 others identified in the literature.

Case Description

A 64-year-old female presented with a type "C", ASIA "E" T11 fracture. The thoracolumbar pedicle screw fixation was supplemented with bone cement due to her underlying severe osteoporosis. During the fluoroscopy-guided supplementation with bone cement, a leak through the paravertebral venous system was noted. Thirty minutes later, the patient acutely developed extreme respiratory failure and required mechanical ventilation for the next 2 days. The diagnosis of pulmonary embolism due to bone cement was confirmed on a contrast computed tomography study of the chest.

Conclusion

Symptomatic pulmonary cement embolization supplementing transpedicular screws placement for osteoporotic bone is rare. Here, we present a 64-year-old female who during transpedicular fixation of a T11 fracture developed an acute pulmonary embolism from the bone cement resulting in the need for 2 days of postoperative artificial ventilation.

Intracardiac, pulmonary cement embolism in a 67-year-old female after cement-augmented pedicle screw instrumentation: A case report and review of literature

BACKGROUND

We report a case of Intracardiac, pulmonary, and intravenous cement embolism after cement-augmented pedicle screw instrumentation in treating spondylolisthesis underlying osteoporotic bone, which was successfully managed by conservative treatment. We describe the treatment and outcome of the patient, hoping to shed light on the management of bone cement embolism.

CASE SUMMARY

A 67-year-old female suffered from progressive low back pain and numbness in lower extremities for 30 years. She was diagnosed with L4 and L5 spondylolisthesis, spinal stenosis, and osteoporosis. The patient underwent spinal canal decompression, an interbody fusion of L4/5 and L5/S1, cement-augmented pedicle screw instrumentation in L4-L5 segments, and regular pedicle screw in S1 segments. Three days postoperatively, a sudden drop in oxygen saturation occurred. Computerized tomography scan confirmed Intracardiac, pulmonary, and intravenous embolism. The patient was treated conservatively by continuous low-flow oxygen inhalation, anti-coagulation, and antibiotic therapy for 1 mo and continued anticoagulation treatment for 6 mo. The patient showed no further symptoms in a 30-mo follow-up.

CONCLUSION

Intracardiac, pulmonary cement embolism after cement-augmented pedicle screw instrumentation is extremely rare. Careful clinical and radiographic evaluation is required in multiple sites of bone cement embolism. Conservative treatment may be a primary consideration in scattered emboli without life-threatening conditions, but a clinical decision should be made on an individualized basis.

Symptomatic pulmonary cement embolism after pedicle screw polymethylmethacrylate cement augmentation: A case report and review

Background:

In osteoporotic patients, a useful technique for significantly enhancing the strength of a pedicle screw is augmentation with polymethylmethacrylate cement. However, a rare complication of this procedure is a symptomatic pulmonary cement embolism.

Case Description:

A pedicle screw cement augmentation was performed in a middle-aged female for the failed back syndrome. When she developed symptomatic pulmonary cement emboli, she was successfully managed with conservative measures, including anticoagulation.

Conclusion:

Despite the increased use of cement augmentation for pedicle screw placement and the relatively high incidence of cement leakage into the prevertebral venous system, symptomatic cement pulmonary embolism remains rare. The management of such symptomatic CPE should be evaluated and treated based on both the size and location of the embolism. Here, we presented this case while reviewing three symptomatic and four asymptomatic cases from the literature.

Surgical Trend Analysis for Use of Cement Augmented Pedicle Screws in Osteoporosis of Spine: A Systematic Review (2000-2017)

STUDY DESIGN

Systematic review.

OBJECTIVES

(1) Study indications for cement-augmented pedicle screws (CAPS) in patients with osteoporosis. Have they changed over the years (2000-2017)? Are there any differences in usage of CAPS based on the geographical region? (2) What were the outcome of the studies? (3) What are the complications associated with this technique?

METHODS

Electronic database and reference list of desired articles were searched from the database (2000-2017). Articles were selected discussing indications, clinical and radiological outcomes, and complications in cases of preexistent osteoporosis treated surgically using CAPS.

RESULTS

Seventeen studies were identified; 3 were comparative studies and had a control arm (cemented vs noncemented screws). Most studies originated from Europe (10) or Asia (7). Painful vertebral fracture with or without neurological deficit, Kummell's lesion, deformity and failure to respond to conservative treatment are the common indications for cement augmentation. Visual analogue scale score was the most commonly used to assess pain and average improvement after surgery was 6.1. Average improvement in kyphosis was 13.21° and average loss of correction at the end of the study was 3°. Cement leak was the most common complication observed and pulmonary cement embolism was the most dreaded complication. Nevertheless, majority of cement leaks discussed in studies were asymptomatic.

CONCLUSION

CAPS are being increasingly used in osteoporotic spine. Pain scores, functional quality of life, and neurological function indices were studied. CAPS improved anchorage in osteoporotic vertebra and helped improve/maintain clinical and radiological improvement. Common risks of cement leak were observed.

Pulmonary cement embolism following cement-augmented fenestrated pedicle screw fixation in adult spinal deformity patients with severe osteoporosis (analysis of 2978 fenestrated screws)

INTRODUCTION

There is very limited information about pulmonary cement embolism (PCE) following cement-augmented fenestrated pedicle screw (CAFPS) fixation in the literature. The aim of this study to report the incidence of PCE following CAFPS fixation in adult deformity patients with severe osteoporosis and to identify risk factors such as; the number of levels, number of screws, and the cement volume used.

METHODS

281 patients (204F, 77M) in whom CAFPS fixation was used during deformity surgery were included. All patients' routine postop 2 day chest X-rays and any available CT scans were reviewed by two radiologists. In patients with PCE, preop, early postop, and latest echocardiography studies were compared in terms of changes in pulmonary artery pressure (PAP) and right ventricular dilatation. Estimated cement volume used was calculated as: 2 cc (1 cc + 1 cc) per thoracic and 3 cc (1.5 cc + 1.5 cc) per lumbar levels, which are our routine protocol. Statistical analysis for risk factors was assessed with point biserial correlation test.

RESULTS

Average age is 70.5 (51-89) and average follow-up is 3.2 years (2-5). A total of 2978 CAFPS were instrumented with a mean of 10.5 levels (2-16) in 281 patients. PCE was diagnosed radiologically in 46 patients (16.3%). Among these 46 patients, PCE was clinically symptomatic in only 4 patients. Overall incidence of symptomatic PCE was 1.4% (4 of 281). Symptomatic PCE was statistically significant: when CAFPS fixation was performed > 7 levels; > 14 screws were used, and > 20-25 cc cement was used for augmentation (r = 0.378). In PCE group, mean preop PAP values of 27.40 (20-37) mm/Hg increased to 32.34 (20-50) mm/Hg in early postop and decreased to 28.29 (18-49) mm/Hg at final follow-up. In symptomatic PCE patients, mean preop PAP values of 30.75 (28-36) mm/Hg increased to 45.74 (40-50) mm/Hg in early postop and decreased to 38.75 (37-40) mm/Hg at final follow-up.

CONCLUSION

This study showed an overall 16.3% radiological PCE and 1.4% symptomatic PCE incidence when CAFPS were used due to severe osteoporosis. The symptomatic PCE risk was significant when CAFPS were > 7 levels; > 14 fenestrated screws; and > 20-25 cc cement volume is used and this may cause PAP increase and right ventricular dilatation.

Risk of cement leakage and pulmonary embolism by bone cement-augmented pedicle screw fixation of the thoracolumbar spine

BACKGROUND

Cement-augmented pedicle screw instrumentation (CAPSI) of the thoracolumbar spine is indicated in osteoporosis or osteopenia to improve pullout strength and biomechanical stability of pedicle screws (PS). Only a few studies report on the incidence of pulmonary cement embolism or other complications associated with CAPSI.

PURPOSE

The aim of this retrospective study was to assess the rate of CAPSI-associated complications.

STUDY DESIGN

Retrospective cohort study.

PATIENT SAMPLE

Patients who underwent CAPSI due to spinal tumors or degenerative spine disease.

OUTCOME MEASURES

Cement leakage, pulmonary cement embolism (PCE), mortality rate.

METHODS

Our clinical database was reviewed for patients who underwent CAPSI between January 2012 and June 2015. A total of 165 patients (mean age 71±11.2; range: 46 to 93 years; m=62, f=103) were included. Indications were osteoporotic fractures (n=40), spinal metastases (n=57), degenerative (n=49) or infectious spine disease (n=5), and traumatic vertebral fractures (n=14) with an associated osteoporosis. Every patient received between 2 and 21 (mean 8±3.3) cement-augmented pedicle screws in the thoracolumbar and lumbosacral spine. Both intraoperative cement leakage in prevertebral veins, the inferior vena cava, and/or pulmonary arteries, and leakage detected on postoperative imaging were evaluated. We assessed the incidence of clinically symptomatic and asymptomatic events.

RESULTS

In 29 of 31 patients with intraoperative suspicion of cement leakage into prevertebral veins or the inferior vena cava on lateral fluoroscopy, which were without hemodynamic relevance, cement extrusion was confirmed on postoperative X-ray or computed tomography (CT) scan. In three of eight patients with suspicion of PCE, PCE was verified on thoracic CT. Four patients experienced life-threatening intraoperative hemodynamic reactions, either due to cement embolism (n=2; 1.2%) or anaphylactic shock (n=2; 1.2%) with need for intraoperative cardiopulmonary resuscitation in three cases. Two patients died due to fulminant PCE. Three patients with dyspnea 1 day after surgery were also confirmed with PCE on chest CT. In five patients, an asymptomatic PCE was found incidentally on postoperative imaging. In addition, 68 patients with cement leakage into prevertebral veins or the ascending cava vein were found incidentally on postoperative spine X-ray or CT. Two of 10 patients with intraspinal epidural cement leakage required revision surgery. One hundred ten of 165 patients (66.7%) had clinically asymptomatic cement leakage. Thirteen patients had PCE (7.9%), of whom five (3.0%) were symptomatic. Two patients experienced intraoperative cement-induced anaphylaxis (1.2%). The overall symptomatic complication rate was 5.5% (n=9). The 30-day mortality rate was 1.8% (n=3).

CONCLUSIONS

CAPSI bears a high risk of asymptomatic cement leakage. The risk for associated severe complications was also relatively high and probably underestimated considering the retrospective nature of the present study. A strict indication for cement augmentation, especially in patients with cardiac predisposition, should be the consequence. We doubt that technical aspects of cement application and/or different types of cement are capable of reducing the risk of these complications substantially.

Cement embolism into the venous system after pedicle screw fixation: case report, literature review, and prevention tips

The strength of pedicle screws attachment to the vertebrae is an important factor affecting their motion resistance and long term performance. Low bone quality, e.g. in osteopenic patients, keeps the screw bone interface at risk for subsidence and dislocation. In such cases, bone cement could be used to augment pedicle screw fixation. But its use is not free of risk. Therefore, clinicians, especially spine surgeons, radiologists, and internists should become increasingly aware of cement migration and embolism as possible complications. Here, we present an instructive case of cement embolism into the venous system after augmented screw fixation with fortunately asymptomatic clinical course. In addition we discuss pathophysiology and prevention methods as well as therapeutic management of this potentially life-threatening complication in a comprehensive review of the literature. However, only a few case reports of cement embolism into the venous system were published after augmented screw fixation.

[Experiences with cement leakage after balloon kyphoplasty]

BACKGROUND

Kyphoplasty is associated with a low incidence of cement leakage and this usually tends to be clinically asymptomatic. However, there is a potential for life-threatening complications from extraspinal leakage resulting in vascular, cardiac and pulmonary embolisms. A total of eight cases of open surgical thrombectomy for cardiopulmonary cement leakage have been published in the current literature to date. Besides the description of a consecutive series with special reference to extraspinal cement leakage this article presents the results after successful endovascular removal of intravenous cement fragments following kyphoplasty in two patients.

MATERIALS AND METHODS

In 46 cases following balloon kyphoplasty the number and amount of extraspinal venous cement leakage was retrospectively determined using computed tomography (CT). The number of cement embolisms into the pulmonary venous system was differently revealed for patients showing no extravertebral leakage or leakage only into the external vertebral venous plexus compared to leakage into the major venous vessels, azygos and hemiazygos vein or inferior vena cava.

RESULTS

In 8 out of 046 cases (17.4 %) leakage into the external vertebral venous plexus was detected. In 5 out of 8 cases without involvement of the azygos/hemiazygos vein or inferior vena cava no pulmonary cement embolism was detected. In 3 out of 8 cases the inferior vena cava or azygos/hemiazygos vein was reached and additionally asymptomatic peripheral pulmonary cement embolism was induced in these cases. In two cases harboring residual intravasal cement fragments treatment was successful using endovascular extraction techniques.

CONCLUSIONS

A computed tomography scan after kyphoplasty is recommended for all cases. If there is involvement of the inferior vena cava or the azygos/hemiazygos vein an additional CT scan of the chest should follow, even in asymptomatic cases. Residual intravasal cement fragments are safely extractable using endovascular techniques.