Percutaneous vertebroplasty and balloon kyphoplasty for the treatment of osteoporotic vertebral compression fractures and osteolytic tumours

Biportal Endoscopic Paraspinal Decompression for Epidural Cement Leakage Removal: A Technical Note

OBJECTIVE

We aimed to preliminarily explore the efficacy and safety of unilateral biportal endoscopy for the treatment of epidural cement leaks. We report a patient who underwent epidural cement leakage removal and achieved endoscopic spinal decompression.

METHODS

A 67-year-old female patient underwent biportal endoscopic paraspinal decompression following percutaneous vertebroplasty for an osteoporotic fracture that resulted in neurologic impairment due to epidural cement leakage. A transforaminal biportal endoscopic surgery was performed to remove the leaked cement, and the left L1 and bilateral L2 nerves were decompressed.

RESULTS

The patient's postoperative clinical course was uneventful.

CONCLUSIONS

A paraspinal approach that avoids a posterior approach reduces the need to remove stabilizing facet bone, is truly minimally invasive and does not involve an instrumented fusion, maybe a helpful addition in the minimally invasive spine surgeon's armamentarium.

Analgesic efficacy and safety of percutaneous thermal ablation plus cementoplasty for painful bone metastases: a systematic review and meta-analysis

PURPOSE

To conduct a systematic review and meta-analysis of publications to evaluate the analgesic efficacy and safety of percutaneous thermal ablation (PTA) plus percutaneous cementoplasty (PCP) (PTA + PCP) for painful bone metastases.

METHODS

We searched PubMed, Cochrane Library and Embase for articles published up to October 2022. Outcomes were a 10-point pain scale, morphine equivalents daily dose (MEDD) and complications. A subgroup confined to spinal bone metastases was analyzed.

RESULTS

Twenty-one articles were selected for the analysis. The 21 selected articles involved a total of 661 cases. The pooled pain scales at pre-PTA + PCP, 1 day, 1 week and 1-, 3-, and 6 months post-PTA + PCP were 7.60 (95% confidence interval [CI], 7.26-7.95, I2 = 89%), 3.30 (95% CI, 2.25-4.82, I2 = 98%), 2.58 (95% CI, 1.99-3.35, I2 = 94%), 2.02 (95% CI, 1.50-2.71, I2 = 93%), 1.78 (95% CI, 1.26-2.53, I2 = 95%), and 1.62 (95% CI, 1.14-2.31, I2 = 88%), and in the subgroup, 7.97 (95% CI, 7.45-8.52, I2 = 86%), 3.01 (95% CI, 1.43-6.33, I2 = 98%), 2.95 (95% CI, 1.93-4.51, I2 = 95%), 2.34 (95% CI, 1.82-3.01, I2 = 68%), 2.18 (95% CI, 1.57-3.03, I2 = 78%), and 2.01 (95% CI, 1.16-3.48, I2 = 86%). Mean MEDD decreased up to 3 months post-PTA + PCP in 4 articles. The overall pooled major complication rate was 4% (95% CI, 2-6%, I2 = 2%).

CONCLUSIONS

The updated systematic review and meta-analysis indicates that PTA + PCP for painful bone metastases is safe, and can lead to rapid and sustained pain reduction.

Vesselplasty for the treatment of osteoporotic vertebral compression fractures with peripheral wall damage: a retrospective study

STUDY DESIGN

A retrospective study.

OBJECTIVE

The clinical efficacy of vertebroplasty and kyphoplasty treating osteoporotic vertebral compression fractures (OVCF) has been widely recognized in recent years. However, there are also disadvantages of bone cement leakage (BCL), limited correction of kyphosis and recovery of vertebral height. Nowadays, in view of these shortcomings, vesselplasty has been widely used in clinical practice. The objective of this study is to assess its clinical effect and application value for the treatment of OVCF with peripheral wall damage.

METHODS

62 patients (70 vertebrae) treated for OVCF with peripheral wall damage using vesselplasty retrospectively reviewed. The data collection included operation time, volume of bone cement, relevant surgical complications, visual analog scale (VAS), Oswestry disability index (ODI), vertebral body height and kyphosis Cobb angle.

RESULTS

The volume of bone cement was 3-8 (5.3 ± 1.3) ml. There were 3 vertebrae of BCL (4.3%). VAS and ODI at different time points after operation were decreased compared with before operation (all p < 0.05). There were no statistical differences between VAS or ODI at different postoperative time points (p > 0.05). Vertebral body height and Cobb angle at different time points after operation were improved compared with before operation (all p < 0.05). There were no statistical differences between vertebral body height or Cobb angle at different postoperative time points (all p > 0.05).

CONCLUSIONS

Vesselplasty may reduce the risk of BCL and better control the dispersion of bone cement in the treatment of OVCF. It relieves pain, restores vertebral body height and corrects kyphosis, especially in OVCF with peripheral wall damage. Therefore, vesselplasty is safe and worthy of clinical application.

Adherence to the evidence-based recommendations in managing bone health, pain, and mobility of patients with multiple myeloma: a mixed method in the Palestinian healthcare system

BACKGROUND

Consensus/evidence-based recommendations for assessing, managing, and monitoring bone health, pain, and mobility in patients with multiple myeloma were developed. This study was conducted to assess the adherence of the hematologists-oncologists to the consensus/evidence-based recommendations for assessing, managing, and monitoring bone health, pain, and mobility in patients with multiple myeloma who received care in the Palestinian healthcare system.

METHODS

A mixed method was used in this study. The consensus/evidence-based recommendations were identified through a systematic search in Scopus, PubMed, SpringerLink, ScienceDirect, and Google Scholar. A panel of 5 researchers (3 hematologists-oncologists, 3 medical students, and 1 pharmacologist) sorted the consensus/evidence-based recommendations and developed the survey tool during 3 iterative meetings. The extent to which the hematologists-oncologists in the 5 centers caring for patients with multiple myeloma adhered to the consensus/evidence-based recommendations was assessed using a questionnaire.

RESULTS

Responses were collected from 10 hematologists-oncologists in all 5 healthcare centers where patients with multiple myeloma receive healthcare in the West Bank of Palestine. The median number of years in the practice of the hematologists-oncologists was 7.5 [2.75, 14.0] years and the median number of patients with multiple myeloma care per month was 12.5 [7.5, 21.25]. The vast majority (90%) of the hematologists-oncologists reported inadequate adherence to screening for medication problems related to bone health, pain, cardiopulmonary fitness, healthy behaviors, nutritional deficits, and mental health. Of the hematologists-oncologists, 70% reported inadequate adherence to ordering and evaluating calcium, vitamin D, alkaline phosphatase, electrolytes, and phosphorus levels to monitor bone health and 60% reported inadequate adherence to prescribing calcium and vitamin D supplements whenever there was a need.

CONCLUSION

The findings of this study suggested inadequate adherence to the consensus/evidence-based recommendations and highlighted areas for improvement to ensure that patients receive optimal care. The findings suggested a need for further education and training on the latest guidelines and recommendations. Decision-makers and policymakers might need to design measures and implement policies to improve adherence to the consensus/evidence-based recommendations. Addressing these gaps in adherence to the consensus/evidence-based recommendations may improve the care and outcomes of patients with multiple myeloma.

Recompression of Augmented Vertebrae after Balloon Kyphoplasty Is a Risk of Adjacent Vertebral Fracture

Introduction

This study aimed to identify factors associated with adjacent vertebral fracture (AVF) incidence after balloon kyphoplasty (BKP).

Methods

To perform the analyses, 133 vertebrae of 128 patients who underwent BKP for osteoporotic vertebral compression fracture were retrospectively investigated. According to the presence of AVF throughout a 1-year period following BKP, patients were divided into AVF (n = 22) and non-AVF (n = 111) groups. The groups were compared with respect to pre- and postoperative parameters, including the incidence of recompression of augmented vertebrae (RAV). RAV was defined as a decrease in anterior vertebral body height of at least 5 mm within the 3 months that followed BKP. To identify factors associated with AVF incidence, univariate and multivariate analyses were performed.

Results

The univariate analysis revealed that the AVF group had a lower cement augmentation ratio, greater preoperative wedge angle, lower preoperative vertebral body height, lower postoperative vertebral body height 3 months post-BKP, and a greater change in vertebral body height and rate of RAV than the non-AVF group. Multivariate analysis revealed that low preoperative vertebral body height and RAV occurrence were associated with AVF incidence.

Conclusions

To the best of our knowledge, this study is the first to indicate that RAV is a risk factor for AVF. Study findings indicate that the incidence of AVF can be decreased if RAV development is avoided.

The usefulness of vertebral needle targeting simulation training system using ray-summation imaging: experimental study

PURPOSE

Using the multi-detector computed tomography and related three-dimensional imaging technology, we developed a vertebral needle targeting simulation training system named spinal needling intervention practice using ray-summation imaging (SNIPURS). Herein, we assessed the utility of SNIPURS by evaluating changes in the learning curves of SNIPURS trainees.

METHODS

Twenty-one examinees were enrolled: seven experienced operators (expert group), seven trainees with coaching (coaching group), and seven trainees without coaching (non-coaching group). They performed six tests of vertebral needle targeting simulation on the workstation-generated spinal ray-summation images of six patients with vertebral fractures. In each test, they determined the bilateral trans-pedicular puncture points and angles on two thoracic and two lumbar vertebrae on ray-summation imaging (i.e., 8 simulations per test). The coaching group received coaching by a trainer after Tests 1 and 4, while the others did not. Scores were given based on the trans-pedicular pathway (1 point) or not (0 point). Eight virtual needles were evaluated in each of Tests 1-6.

RESULTS

Among the three groups, the expert group had the highest average scores on Tests 1-4 (expert: 3.86, 6.57, 7.43, and 7.57; coaching: 1.86, 6.14, 6, and 6.29; and non-coaching: 1.14, 4.14, 4.71, and 4.86). The coaching group's scores caught up with the expert groups' average scores on Tests 5 and 6, whereas those of the non-coaching group did not (expert and coaching: 7.86 and 8.00, non-coaching: 5.86 and 7.14). All examinees in the expert and coaching groups achieved a perfect score on the final Test 6, whereas three of the seven non-coaching trainees did not.

CONCLUSION

SNIPURS might be suitable for vertebral needle targeting training. The coaching provided during SNIPURS training helped the trainees to acquire the spinal puncture techniques in PVP.

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.

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

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

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

Paraplegia due to intradural cement leakage after vertebroplasty: a case report and literature review

Background

Vertebroplasty (VP) is considered an alternative therapy in an osteoporotic compression fracture that failed conservative treatment. However, cement leakage into the intradural space can cause catastrophic complications. To the best of our knowledge, intradural cement leakage following VP has been reported only in 7 cases. We report here a case of intradural cement leakage following VP with a literature review.

Case presentation

An 84-year-old female with an L1 osteoporotic fracture underwent percutaneous VP at a local hospital. Immediately after the procedure, she complained of weakness, numbness, and pain in both legs, and her back pain aggravated. She was transferred to our hospital. The initial muscle power was grade 2 for the right leg and grade 4 for the left leg. Computed tomography (CT) scan showed intradural cement leakage from T10 to L2. Magnetic resonance imaging showed an intradural mass lesion. Although we performed total laminectomy with durotomy and removed intradural cement completely, the neurological deficit did not completely recover. The muscle power was grade 3 for the right leg and grade 4 for the left leg at the last follow-up.

Conlcusions

If a neurological deficit is found after VP, a CT scan should be taken to confirm the pattern of cement leakage. In case of intradural cement leakage, surgical decompression should be recommended to improve neurological deficit. To prevent intradural cement leakage during the VP, the needle tip should not perforate the medial wall of the pedicle with appropriate viscosity of cement.

Gallbladder gangrene after percutaneous vertebroplasty, an uncommon presentation of vascular complication: a case report and analysis of the causes

We present a case of an 81-year-old man with gallbladder gangrene after percutaneous vertebroplasty (PV) that was successfully treated via laparoscopic cholecystectomy (LC). The patient underwent multilevel, thoracic PV for painful osteoporotic compression fractures. PV performed at the T6 level was complicated by severe abdominal pain owing to direct embolization of the right T6 segmental artery with penetration of bone cement into the radicular artery beneath the pedicle. Cement leakage, especially arterial embolization of cement into the general circulation, is a known potential complication following PV. Serious complications related to PV augmentation procedures, such as vertebroplasty and kyphoplasty, are rare and most often result from local cement leakage or venous embolization. Combined with this case report, we reviewed the literature regarding the unusual occurrence of direct arterial cement embolization during PV and analyzed the causes to alert clinicians to this potentially rare vascular complication.

Rare Episode of Cement Leakage During Vesselplasty in a Case of Vertebral Compression Fracture

BACKGROUND

Osteoporosis has become an important issue owing to the increasing elderly population. It is the most common cause of vertebral compression fracture. Conservative treatment is often ineffective, whereas surgical treatment has a vital role in compression fracture. Vesselplasty is a new surgical alternative to traditional vertebroplasty and kyphoplasty. It uses a polyethylene terephthalate balloon that functions as both a vertebral body expander and a bone cement container. We present a rare but catastrophic case of cement leakage during vesselplasty resulting in devastating neurologic compromise. This case highlights the need for awareness of vesselplasty safety and the importance of using a low-temperature bone cement.

CASE DESCRIPTION

A 77-year-old woman presented with debilitating back pain owing to acute T6 compression fracture as detected by magnetic resonance imaging. Under biplanar fluoroscopy, vesselplasty using a polyethylene terephthalate balloon container was performed at the T6 vertebrae. During cement injection, balloon rupture and cement leakage occurred compromising the spinal canal. Emergent laminectomy and cement removal were performed. Paraplegia developed postoperatively.

CONCLUSIONS

Though vesselplasty is claimed to be safe, cement leakage related to balloon rupture occurred in our case. Furthermore, thermal effects were difficult to observe during polymethyl methacrylate polymerization. Heat not only might cause irreversible complications but also might make the balloon rupture more easily.

Long Term Survival of Pathological Thoracolumbar Fractures Treated with Vertebroplasty: Analysis Using a Nationwide Insurance Claim Database

Background: There are still debates on the long-term outcome of treating pathological thoracolumbar fractures, including osteoporosis and oncologic problems, using vertebroplasty. Methods: We collected 8625 patients with pathological thoracolumbar fractures (ICD-9-CM codes 733.13 combined with 805.2 or 805.4) between the years of 2003 to 2013, from the two million random samples from the National Health Insurance Research Database in Taiwan. Survival analysis was conducted to estimate the mortality risks of different treatments, including vertebroplasty (n = 1389), conventional open surgery (n = 1219), or conservative treatment (n = 6017). A multivariable Cox proportional hazard model was constructed for adjustment of age, gender, comorbidities and complications. Results: Crude incidence rate of patients with pathological thoracolumbar fractures in Taiwan gradually increased year by year. Compared with conservative treatment, conventional open surgery and vertebroplasty seemed to improve long-term survival with adjusted hazard ratios (aHR) of 0.80 (95% confidence interval (CI) 0.70–0.93), and 0.87 (95% CI 0.77–0.99), respectively. The survival advantage of vertebroplasty appeared more evident for those aged over 75. However, we were unable to rule out confounding by indication. Conclusion: Although conventional open surgery would usually be the best choice for the treatment of patients with pathological thoracolumbar fractures, database information from current real-world practice appears to support vertebroplasty as a viable choice for elderly people over 75 years of age.

Late-onset spondylodiscitis and psoas abscess, 5 years after percutaneous balloon kyphoplasty: a case report

Postoperative infection following percutaneous balloon kyphoplasty (PBK) is a rare complication and delayed onset infection is very rare. We report the case of a 62-year-old male, who developed spondylodiscitis and psoas abscess 5 years after two-level, L2 and L3 PBK. He was initially treated with abscess aspiration and long term antimicrobial treatment. Eventually, due to failure of conservative treatment he underwent anterior decompression, radical debridement of the infected tissue and non-instrumented fusion with strut graft, with excellent results.

Full-Endoscopic Lumbar Foraminoplasty for Symptomatic Cement Leakage with Exiting Nerve Root Impingement

BACKGROUND

Foraminal stenosis, a common disorder occurring in elderly patients, is often caused by narrowing of the foramen, resulting in the confinement of neural structures by the tissue and vertebrae. Full-endoscopic lumbar foraminoplasty (FELF) is an effective treatment option for patients with foraminal stenosis. However, to the best of our knowledge, no previous study has reported the treatment of symptomatic cement leakage. We report a case of symptomatic cement leakage treated with FELF with the patient under local anesthesia.

CASE DESCRIPTION

An 85-year-old woman was admitted to our spine unit because of lower back pain. The patient had presented with lower back pain and new-onset left thigh pain after vertebroplasty performed 3 months previously. The patient was not able to walk and was bedridden. To overcome this problem, T12 percutaneous vertebroplasty and left transforaminal L3-L4 foraminoplasty was performed with the patient under local anesthesia. After surgery, the patient was able to walk and was discharged 4 days postoperatively.

CONCLUSION

The present report has shown that FELF can successfully remove symptomatic cement leakage, resulting in pain relief.

A Comparison of Percutaneous Vertebroplasty Versus Conservative Treatment in Terms of Treatment Effect for Osteoporotic Vertebral Compression Fractures: A Meta-Analysis

Background. Osteoporotic vertebral compression fractures (OVCFs) are common in older patients, which can cause back pain and even increase morbidity. However, the optimal therapy for patients with OVCFs remains unknown. Percutaneous vertebroplasty (PVP), a minimally invasive procedure, has been a therapy option that is known to be effective in the pain management. Aim. The meta-analysis aims to summarize current best evidence on the efficacy of PVP and conservative treatment (CT) for pain management and functional results among OVCFs patients. Methods. We searched the publications on comparison of the efficacy of PVP versus CT for OVCFs patients up to November 2018. After rigorous reviewing on the quality, the data were extracted from eligible trials. All trials analyzed the summary hazard ratios of the endpoints of interest. Results. Moderate-strong evidence indicated that PVP had benefits on pain relief at 1 week and 1 month, but not at 3 months. With regard to the quality of life, no significant differences were found in the Roland-Morris Disability Questionnaire (RMDQ). However, there is significant difference in terms of EuroQol and Quality of Life Questionnaire of the European Foundation for Osteoporosis but not the RMDQ. Moreover, there were no any benefit in terms of vertebral fracture between groups. Conclusions. The meta-analysis showed that patients treated with vertebroplasty were associated with better pain relief and improved quality of life, without increasing the incidence of vertebral fracture compared with the CT group.

Vertebral Body Lavage Reduces Hemodynamic Response to Vertebral Body Augmentation With PMMA

STUDY DESIGN

Retrospective comparative study.

OBJECTIVES

To assess the effect of vertebral body lavage (VBL) on (1) systemic blood pressure, (2) heart rate, and (3) oxygen saturation following cement augmentation procedures for acute vertebral compression fractures (VCFs).

METHODS

A total of 145 consecutive patients undergoing cement augmentation for acute VCF (mean age 74 ± 12 years, age range 42-96 years; 70% female; 475 levels treated) were allocated to the "lavage group" (n = 61 patients; VBL prior to cement application) and to the "control group" (n = 84 patients, no VBL). Mean arterial blood pressure (MAP), heart rate, and oxygen saturation were monitored immediately prior and 3 minutes after cement injection. Logistic regression analysis was performed with ΔMAP ≥10 mm Hg before and after cement injection as the dependent outcome variable and demographic, radiographic, and procedural factors as independent variables.

RESULTS

MAP decreased by mean 3 ± 7.3 mm Hg before and after cement injection in the "lavage group" and 9 ± 10.5 mmHg in the control group (P < .001). There were no significant differences in terms of heart rate and oxygen saturation before and after cement application within each group, or between the 2 groups. Multivariate logistic regression analyses revealed VBL as an independent factor influencing MAP (adjusted odds ratio: 3.49 [confidence interval, 1.16-10.50], P = .03).

CONCLUSION

VBL prior to cement augmentation procedures reduces the hemodynamic response, most likely resulting from decreased amounts of bone marrow substance displaced into the circulation thereby decreasing the risk of pulmonary fat embolism syndrome.

In Situ Generated Medical Devices

Medical devices play a major role in all areas of modern medicine, largely contributing to the success of clinical procedures and to the health of patients worldwide. They span from simple commodity products such as gauzes and catheters, to highly advanced implants, e.g., heart valves and vascular grafts. In situ generated devices are an important family of devices that are formed at their site of clinical function that have distinct advantages. Among them, since they are formed within the body, they only require minimally invasive procedures, avoiding the pain and risks associated with open surgery. These devices also display enhanced conformability to local tissues and can reach sites that otherwise are inaccessible. This review aims at shedding light on the unique features of in situ generated devices and to underscore leading trends in the field, as they are reflected by key developments recently in the field over the last several years. Since the uniqueness of these devices stems from their in situ generation, the way they are formed is crucial. It is because of this fact that in this review, the medical devices are classified depending on whether their in situ generation entails chemical or physical phenomena.

Anterior Lumbar Interbody Fusion With Cement Augmentation Without Posterior Fixation to Treat Isthmic Spondylolisthesis in an Osteopenic Patient-A Surgical Technique

Background

Anterior lumbar interbody fusion (ALIF) has been well established as an effective surgical intervention for chronic back pain due to osteoporotic vertebral collapse. Historically, ALIF has consisted of an anterior approach to disc height restoration with a subsequent posterior pedicle screw fixation. Although the applications of cement augmentation with posterior fixation have been previously reported, treatment of patients with both isthmic spondylolisthesis and decreased bone mineral density using a stand-alone ALIF is controversial because of concerns for decreased fusion rates and increased subsidence risk, respectively. We report a case of stand-alone ALIF used to treat a low-grade isthmic spondylolisthesis in the setting of idiopathic thoraco-lumbar scoliosis in a patient with secondary degenerative changes and discuss the benefits of this surgical technique in a patient with several comorbidities.

Methods

An osteopenic 66-year-old woman with multiple medical comorbidities and 2 years of left radicular leg pain was found to have a Myerding grade I isthmic spondylolisthesis in the setting of idiopathic thoraco-lumbar scoliosis with secondary changes. The patient underwent an L5-S1 stand-alone ALIF with anterior cement augmentation without posterior pedicle screw fixation.

Results

The patient experienced immediate relief of radicular leg pain postoperatively and had an uneventful course. At 2 years follow-up, she remained symptom free, and radiographs showed excellent fusion and maintenance of intervertebral disc height.

Conclusions

The use of stand-alone ALIF with anterior cement augmentation of the vertebral bodies is a surgical technique that could produce excellent improvement in patients with low-grade isthmic spondylolisthesis in the setting of osteopenia. The use of the all-anterior approach in similar patients with multiple medical comorbidities can also be a useful technique, as it decreases associated morbidity of surgery and complication risks associated with prolonged operative times.

Influence of radiofrequency kyphoplasty on pulmonary function

BACKGROUND

Vertebral compression fractures (VCF) change the natural spinal alignment and inevitably lead to a decreased quality of life.

OBJECTIVE

The aim of the study was to evaluate changes in pulmonary function after VCF were treated by radiofrequency kyphoplasty (RF-TVA).

METHODS

Twenty-five patients were treated with RF-TVA and analyzed in 3 subgroups taking into account the spinal location of the VCF. Pain as measured by visual analogue scale (VAS), Oswestry-Disability-Index (ODI), vertebral height, forced expiratory volume in 1 second (FEV1), and peak expiratory flow (PEF) were assessed before, directly after and 30 days after RF-TVA.

RESULTS

The mean vertebral height was improved in all subgroups, with a minor reduction from one to 30 days postoperatively. The mean VAS and ODI significantly decreased in the main and upper diaphragm groups from baseline to the follow-up after 30 days. Patients treated below the main diaphragm region showed a significant improvement of ODI and a clear trend to significant improvements of VAS. PEF and FEV1 were significantly improved in the main diaphragm group. FEV1 also increased significantly in the upper diaphragm group with a clear trend to significance in the lower diaphragm group.

CONCLUSIONS

Results indicate that RF-TVA may improve pulmonary function especially in cases where fractures are located in the main spinal region of the diaphragm.

Is Redo Vertebroplasty an Effective Treatment on the Same Vertebra?

OBJECTIVE

Redo vertebroplasty is rarely reported. Previous studies on redo vertebroplasty included a small number of patients and lacked radiographic analysis. The purpose of this study was to assess the radiographic outcomes (restoration of vertebral body) and clinical outcomes (pain relief) in patients with recurrent or unrelieved pain after vertebroplasty with a minimum follow-up duration of 12 months.

MATERIALS AND METHODS

The records of 22 patients (23 cases), who underwent redo vertebroplasty between March 2001 and February 2014, were analyzed. Vertebral height loss (VHL) and wedge angle (WA) were measured before and after redo vertebroplasty. Subjective back pain was assessed via the numeric rating scale (NRS) score.

RESULTS

VHL after the initial vertebroplasty was 18.7%. Preoperative and final VHL of redo vertebroplasty were 32.3 and 18.3%, respectively. WA after initial vertebroplasty was 9.5°. Preoperative and final WA of redo vertebroplasty was 13.9° and 9°, respectively. Changes of VHL and WA values at each time point were significant (p < 0.01). The change of NRS pain score at each time point, including the period between post-initial vertebroplasty and final follow-up, was statistically significant (p < 0.01); 18 patients (82%) showed marked pain relief and 4 patients (18%) showed partial pain relief.

CONCLUSIONS

Redo vertebroplasty seems to be an effective way to achieve pain relief and vertebral body height restorations without major complications in patients with unrelieved or recurrent back pain after vertebroplasty.

LEVEL OF EVIDENCE

Level 4, case series.

Morphological changes of vertebral compression fracture with intra-vertebral cleft treated with percutaneous vertebroplasty

BACKGROUND

Vertebroplasty represents an established treatment option for osteoporotic vertebral compression fracture (OVCF), but its radiographic and clinical outcomes have not been clearly described in patients with intra-vertebral cleft (IVC). The aim of this study was to assess vertebral height restoration, recollapse and change of back pain in OVCF patients with or without IVC.

METHODS

The records of 108 patients with IVC (group I) and 233 patients without IVC (group II) were included in our analysis between March 2001 and February 2014. The heights of the anterior, middle, and posterior columns, as well as the wedge angle (WA) of the fractured vertebral body were measured. For each vertebral column, the mean height of the superior and inferior vertebral body served as reference. Pre-operative, postoperative, and final compression rates (CR), as well as restoration and recollapse rates were calculated for each column. Subjective back pain was assessed as the numeric rating scale (NRS) score.

RESULTS

The overall incidence of IVC in OVCF patients who underwent vertebroplasty was 20.8% (127/611 patients). Group I showed significantly higher CR over the entire follow-up period, with the exception of CR for the anterior column at final follow-up, and CR for the posterior column throughout the follow-up. The mean restoration rates at the anterior and middle column immediately after vertebroplasty were also significantly larger in group I. Recollapse rate in all columns was similar for groups I and II. The mean wedge angle was significantly larger in group I over the entire follow-up period. The groups did not differ in terms of NRS score at final follow-up.

CONCLUSIONS

Vertebroplasty restores vertebral body heights and WA more effectively in OVCF patients with IVC, and provides satisfactory radiographic and clinical outcomes regardless of the presence of IVC.

Surgical options for osteoporotic vertebral compression fractures complicated with spinal deformity and neurologic deficit

INTRODUCTION

This paper describes surgical options for Osteoporotic vertebral compression fracture (OVCF) with acute flexible or chronic rigid kyphosis, and pseudarthrosis complicated with pain and neurologic deficit.

METHODS

This study has two components. a) A prospective clinical study of surgical treatment of 31 patients (age: 69±11 years) with either acute flexible or progressive pseudarthrotic kyphosis manifested with severe pain or neurological deficit between 2010 and 2014. Eleven patients exhibited neurocompression (Frankel B, C, D). Surgery consisted in indirect reduction, kyphoplasty, and short posterior instrumentation in 28 patients and multilevel instrumentation in three. b) The second component involved a literature search of OVCF complicated with acute or painful chronic deformities and neurologic deficit, managed with open surgical approach.

RESULTS

Indirect reduction, kyphoplasty and short posterior stabilization can restore satisfactory anatomic alignment and neurological deficit. Multilevel instrumentation was used for rigid long kyphosis. Complications were related to a) screw pull out and junctional kyphosis (4 patients) one of the patients also developed anterior migration of cement, b) cement leakage (4 patients). L5 radiculopathy occurred in one patient. The others remained asymptomatic. The literature review concluded that corpectomy with anterior, posterior or combined instrumentations is indicated for burst fractures, or rigid kyphosis with neurocompression. Prompt decompression with anatomical alignment may restore paraplegia. Complications were germane to osteoporotic bone predisposing to hardware loosening or cut out and dislodgement of instrumentation.

DISCUSSION

Neurologic deficit associated with fractures or progressive pseudarthrotic kyphosis effectively may respond to indirect postural reduction, kyphoplasty and posterior percutaneous short segment transpedicle instrumentation. For burst fractures and rigid chronic kyphosis corpectomy reconstructed with cages and anterior, or posterior or combined instrumentations can restore and maintain normal anatomy. The following guidelines for optimal surgical instrumentation have been established: To prevent screw loosening and junctional kyphosis the instrumentation should not end within the kyphotic segment. Screws for anterior instrumentation should penetrate the contralateral cortex. Multiple site of fixation or combined anterior and posterior instrumentations dissipate stresses at any one site. Augmentation of transpedicle screw fixation with cement is a sound technical principle. Cement should inserted in a doughy state with minimal pressure to prevent cement complications.

Comparison of radiofrequency kyphoplasty and balloon kyphoplasty in combination with posterior fixation for the treatment of vertebral fractures

BACKGROUND

In case of complex vertebral fractures, posterior fixation is often required for correction of deformity and instability. Fixation is commonly supported by balloon kyphoplasty (BKP) anterior. A development of BKP is radiofrequency-targeted vertebral augmentation (RF-TVA), which leads to comparable results for augmentation and pain relief.

OBJECTIVE

This prospective study evaluates the outcome of posterior fixation combined with RF-TVA or BKP, respectively.

METHODS

VAS, ODI, kyphosis angle and vertebral height of 44 patients were evaluated preoperatively, 3 and 12 months postoperatively.

RESULTS

Both treatments improved vertebral height and kyphosis angle. At 12 months, vertebral height restoration was still significantly better in the BKP group (p < 0.001) and the improvement of kyphosis angle was comparable between both groups (p = 0.71). VAS and ODI improvements were significantly better in the RF-TVA group (p < 0.001). 8% of BKP patients had cement extravasations, compared to 10.5% in the RF-TVA group (p = 1.0).

CONCLUSIONS

Combining posterior fixation with RF-TVA leads to better results of VAS and ODI, whereas the vertebral height restoration was favorable for patients treated with BKP. Cement leakage was comparable between both groups. It was asymptomatic and within reported ranges. Limitations of this study are the patient number and different stabilization instrumentation.

Injectable, biomechanically robust, biodegradable and osseointegrative bone cement for percutaneous kyphoplasty and vertebroplasty

PURPOSE

Poly(methyl methacrylate) (PMMA) cement is widely used for percutaneous kyphoplasty and vertebroplasty (PKP and PVP) but possesses formidable shortcomings due to non-degradability. Here, a biodegradable replacement is developed.

METHODS

Calcium phosphate cement (CPC) was redesigned by incorporating starch and BaSO₄ (new cement named as CPB). The biomechanical, biocompatibility, osseointegrative and handling properties of CPB were systematically evaluated in vitro and in vivo by the models of osteoporotic sheep vertebra, rat subcutaneous implantation and rat femoral defect.

RESULTS

CPB revealed appropriate injectability and setting ability for PKP and PVP. More importantly, its biomechanical strengths measured by in vitro and in vivo models were not less than that of PMMA, while its biodegradability and osseointegrative capacities were significantly enhanced compared to PMMA.

CONCLUSIONS

CPB is injectable, biomechanically robust, biodegradable and osseointegrative, demonstrating revolutionary potential for the application in PKP and PVP.

Effectiveness and safety of percutaneous vertebroplasty in the treatment of spinal metastatic tumor

Objective:

To evaluate the effectiveness, safety and feasibility of percutaneous vertebroplasty in the treatment of spinal metastatic tumor.

Methods:

Thirty-four patients with spinal metastatic tumor who received treatment in the First Affiliated Hospital of Zhengzhou University from May 2014 to June 2015 were selected. Totally fifty diseased vertebrae were treated by percutaneous vertebroplasty. The curative effects were evaluated according to visual analogue scale (VAS) score, Oswestry Dability Index (ODI) and dose of pain reliever. The leakage conditions of bone cement and clinical complications were observed. The patients were followed up for 3 to 12 months.

Results:

The average VAS score and ODI 24 h after treatment were much lower than those before treatment, and the difference had statistical significance (P<0.05). The average VAS score and ODI at different follow-up periods after treatment were not significantly different (P>0.05). During follow up, nine patients stopped taking pain reliever, the dose of 18 patients had obvious reduction, and 7 patients kept previous dose; the incidence of bone cement leakage was 38.25%. Six patients had fever after surgery, but recovered after expectant treatment; 2 patients felt uncomfortable in the right lower limbs, but relieved after expectant treatment.

Conclusion:

Percutaneous vertebroplasty can relieve pain efficiently, improve the daily living ability, and significantly enhance the living quality of patients with spinal metastatic tumors, with small trauma and high safety.

Mid-term outcomes after radiofrequency-targeted vertebral augmentation in the treatment of myeloma associated vertebral fractures

BACKGROUND

Myeloma patients often suffer from painful vertebral fractures (VCF) which impair their quality of life. Common methods for augmentation of the vertebrae are vertebroplasty, kyphoplasty and radiofrequency-targeted vertebral augmentation (RF-TVA).

OBJECTIVE

This study evaluates the long-term effectiveness and safety of RF-TVA in the treatment of myeloma associated VCF.

METHODS

Eighty-seven myeloma patients (mean age: 64.7 ± 9.5 years) with VCF were treated with RF-TVA. Patient data were assessed preoperatively and in five postoperative examinations up to 12 months. Pain was measured with the visual analogue scale (VAS) and the impairment was evaluated with the Oswestry-Disability-Index (ODI) at each examination. In addition, the mid vertebral height, kyphosis angle, and additional fractures were evaluated by x-rays. Furthermore, cement leakage was documented.

RESULTS

The VAS values were significantly improved in comparison to the preoperative values (p≤ 0.001), but slightly fluctuating during the follow-up period. The ODI was also significantly improved (p≤ 0.001), but it showed a worsening from the 12 months evaluation to the 24 months evaluation. The kyphosis angle and the vertebral height were significantly improved after surgery (p = 0.03, p ≤ 0.001), but worsened steadily to the last follow up examination. Cement leakage was asymptomatic and occurred in 18% of the patients. In 10% of the patients additional fractures were detected in the 24 months evaluation.

CONCLUSIONS

The results of our study show that RF-TVA is a safe treatment for myeloma associated vertebral compression fractures, which achieves an acceptable improvement of patient's pain and quality of life.

Minimally invasive spinal surgery for the management of symptomatic spinal metastasis

INTRODUCTION

Symptomatic metastatic spinal disease is on the increase. Minimally invasive spinal surgery has been associated with a lower complication profile when compared to traditional open methods; however there is paucity of literature evaluating the place of percutaneous pedicle screw fixation (PPSF) in the management of spinal metastases. The purpose of the study is to assess the efficacy of Minimally Invasive Spine Surgery (MISS) using PPSF with or without mini-decompression in the management of symptomatic spinal metastases.

MATERIAL AND METHODS

This is a single institution prospective study of 51 consecutive patients with metastatic spinal disease treated with PPSF. Patients presenting with pathological compression fractures and mechanical instability had PPSF, and those with radiological and/or clinical metastatic spinal cord compression (MSCC) underwent an additional mini-decompression. Data collected included patient demographics, Karnofsky's performance status (KPS), pain scores and neurology. Other data included number and location of involved levels, number of instrumented levels, blood loss, accuracy of screw placement and complications.

RESULTS

Of the 51 patients, 49 could be successfully treated with MISS (26 females and 23 males). 26 patients (55%) required a mini-decompression. 27 patients (55%) had improvement in KPS by at least 10 points (p < 0.0005). Only 2 patients (4%) had a worsening of KPS, due to other coexisting problems. Six of the 13 patients improved their neurology by one Frankel grade following surgery and 95% reported improvement in pain. Mean blood loss was 92mls for the fixation only group and 222mls for those requiring mini-decompression, with no other differences between these two surgical groups. Screw positioning was excellent in 91%, with 98% having uncompromised bony hold. Only two patients required revision surgery for aseptic loosening.

CONCLUSION

MISS using PPSF is a safe and reproducible technique that maintains or improves functional outcome in the vast majority of patients presenting with spinal metastases.

Percutaneous Sacroplasty for Painful Bone Metastases: A Case Report

INTRODUCTION

The occurrence of bone metastases is common in patients with advanced cancer. The literature supports percutaneous vertebroplasty and kyphoplasty as minimally invasive procedures to relieve pain and improve quality of life for selected patients with disabling pain from pathological vertebral fractures secondary to bone metastases.

CASE

We describe a case of a 71-year-old patient with castrate-resistant metastatic prostate cancer who underwent sacroplasty for painful sacral metastases. The patient had previously been treated with maximally tolerated analgesics and anticancer therapies including systemic anticancer treatments and local radiotherapy. After sacroplasty, he experienced significant pain reduction and improvement in mobility and function.

CONCLUSION

This case and recent literature demonstrate positive outcomes of sacroplasty in terms of pain reduction and improved mobility. Further research is warranted to establish the role of such minimally invasive percutaneous procedures for pain management in cancer patients.

Cause Analysis of Open Surgery Used After Percutaneous Vertebroplasty and Kyphoplasty

BACKGROUND The aim of this study was to analyze reasons why open surgery was done after percutaneous vertebroplasty and kyphoplasty. MATERIAL AND METHODS Patients (587 vertebral bodies) treated with percutaneous vertebroplasty or kyphoplasty in the Xi'an Honghui Hospital of Shanxi Province from January 2008 to January 2012 were retrospectively analyzed and 13 patients were enrolled in the study. These 13 patients had serious adverse events after percutaneous vertebroplasty or kyphoplasty. Their average age was 64.5 years old. Nine patients had spinal cord injury and 4 had nerve root injury. All the patients underwent open surgery within 4-12 h after definitive diagnosis. RESULTS All 13 cases were followed up (average time 14.1 months, range 3-47 months). Reasons for open surgery included cement extravasation (6 cases, 46.2%), puncture mistake (3 cases, 23.1%), and false selection of indications (4 cases, 30.8%). At last follow-up, skin feeling was better than that before open surgery in 4 cases with nerve root injury, and muscle strength recovered to grade 5 (3 cases) and grade 4 (1 case). In 9 cases with spinal cord injury, 7 patients improved and 2 remained at the same ASIA level. CONCLUSIONS The main reasons for open surgery after percutaneous vertebroplasty and kyphoplasty were cement extravasation (the most common reason), puncture mistake, and false selection of indications.

Electrospun Nanofibrous P(DLLA-CL) Balloons as Calcium Phosphate Cement Filled Containers for Bone Repair: in Vitro and in Vivo Studies

The spinal surgeon community has expressed significant interest in applying calcium phosphate cement (CPC) for the treatment of vertebral compression fractures (VCFs) and minimizing its disadvantages, such as its water-induced collapsibility and poor mechanical properties, limiting its clinical use. In this work, novel biodegradable electrospun nanofibrous poly(d,l-lactic acid-ϵ-caprolactone) balloons (ENPBs) were prepared, and the separation, pressure, degradation, and new bone formation behaviors of the ENPBs when used as CPC-filled containers in vitro and in vivo were systematically analyzed and compared. CPC could be separated from surrounding bone tissues by ENPBs in vitro and in vivo. ENPB-CPCs (ENPBs serving as CPC-filled containers) exerted pressure on the surrounding bone microenvironment, which was enough to crush trabecular bone. Compared with the CPC implantation, ENPB-CPCs delayed the degradation of CPC (i.e., its water-induced collapsilibity). Finally, possible mechanisms behind the in vivo effects caused by ENPB-CPCs implanted into rabbit thighbones and pig vertebrae were proposed. This work suggests that ENPBs can be potentially applied as CPC-filled containers in vivo and provides an experimental basis for the clinical application of ENPBs for the treatment of VCFs. In addition, this work will be of benefit to the development of polymer-based medical implants in the future.

Nanotechnology for treating osteoporotic vertebral fractures

Osteoporosis is a serious public health problem affecting hundreds of millions of aged people worldwide, with severe consequences including vertebral fractures that are associated with significant morbidity and mortality. To augment or treat osteoporotic vertebral fractures, a number of surgical approaches including minimally invasive vertebroplasty and kyphoplasty have been developed. However, these approaches face problems and difficulties with efficacy and long-term stability. Recent advances and progress in nanotechnology are opening up new opportunities to improve the surgical procedures for treating osteoporotic vertebral fractures. This article reviews the improvements enabled by new nanomaterials and focuses on new injectable biomaterials like bone cements and surgical instruments for treating vertebral fractures. This article also provides an introduction to osteoporotic vertebral fractures and current clinical treatments, along with the rationale and efficacy of utilizing nanomaterials to modify and improve biomaterials or instruments. In addition, perspectives on future trends with injectable bone cements and surgical instruments enhanced by nanotechnology are provided.

Does Balloon Kyphoplasty Deliver More Cement Safely into Osteoporotic Vertebrae with Compression Fractures Compared with Vertebroplasty? A Study in Vertebral Analogues

Study Design A biomechanical and radiographic study using vertebral analogues. Objectives Kyphoplasty and vertebroplasty are widely used techniques to alleviate pain in fractures secondary to osteoporosis. However, cement leakage toward vital structures like the spinal cord can be a major source of morbidity and even mortality. We define safe cement injection as the volume of the cement injected into a vertebra before the cement leakage occurs. Our objective is to compare the amount of cement that can be safely injected into an osteoporotic vertebra with simulated compression fracture using either vertebroplasty or balloon kyphoplasty techniques. Methods Forty artificial vertebral analogues made of polyurethane with osteoporotic cancellous matrix representing the L3 vertebrae were used for this study and were divided into four groups of 10 vertebrae each. The four groups tested were: low-viscosity cement injected using vertebroplasty, high-viscosity cement injected using vertebroplasty, low-viscosity cement injected using balloon kyphoplasty, and high-viscosity cement injected using balloon kyphoplasty. The procedures were performed under fluoroscopic guidance. The injection was stopped when the cement started protruding from the created vascular channel in the osteoporotic vertebral fracture model. The main outcome measured was the volume of the cement injected safely into a vertebra before leakage through the posterior vascular channel. Results The highest volume of the cement injected was in the vertebroplasty group using high-viscosity cement, which was almost twice the injected volume in the other three groups. One-way analysis of variance comparing the four groups showed a statistically significant difference (p < 0.005). Conclusions High-viscosity cement injected using vertebroplasty delivers more cement volume before cement leakage and fills the vertebral body more uniformly when compared with balloon kyphoplasty in osteoporotic vertebrae with compression fractures.

The biomechanics of pedicle screw augmentation with cement

BACKGROUND CONTEXT

A persistent challenge in spine surgery is improving screw fixation in patients with poor bone quality. Augmenting pedicle screw fixation with cement appears to be a promising approach.

PURPOSE

The purpose of this study was to survey the literature and assess the previous biomechanical studies on pedicle screw augmentation with cement to provide in-depth discussions of the biomechanical benefits of multiple parameters in screw augmentation.

STUDY DESIGN/SETTING

This is a systematic literature review.

METHODS

A search of Medline was performed, combining search terms of pedicle screw, augmentation, vertebroplasty, kyphoplasty, polymethylmethacrylate, calcium phosphate, or calcium sulfate. The retrieved articles and their references were reviewed, and articles dealing with biomechanical testing were included in this article.

RESULTS

Polymethylmethacrylate is an effective material for enhancing pedicle screw fixation in both osteoporosis and revision spine surgery models. Several other calcium ceramics also appear promising, although further work is needed in material development. Although fenestrated screw delivery appears to have some benefits, it results in similar screw fixation to prefilling the cement with a solid screw. Some differences in screw biomechanics were noted with varying cement volume and curing time, and some benefits from a kyphoplasty approach over a vertebroplasty approach have been noted. Additionally, in cadaveric models, cemented-augmented screws were able to be removed, albeit at higher extraction torques, without catastrophic damage to the vertebral body. However, there is a risk of cement extravasation leading to potentially neurological or cardiovascular complications with cement use. A major limitation of these reviewed studies is that biomechanical tests were generally performed at screw implantation or after a limited cyclic loading cycle; thus, the results may not be entirely clinically applicable. This is particularly true in the case of the bioactive calcium ceramics, as these biomechanical studies would not have measured the effects of osseointegration.

CONCLUSIONS

Polymethylmethacrylate and various calcium ceramics appear promising for the augmentation of pedicle screw fixation biomechanically in both osteoporosis and revision spine surgery models. Further translational studies should be performed, and the results summarized in this review will need to be correlated with the clinical outcomes.

Safety of balloon kyphoplasty in the treatment of osteoporotic vertebral compression fractures in Europe: a meta-analysis of randomized controlled trials

PURPOSE

The study aims to evaluate the safety of balloon kyphoplasty in the treatment of painful osteoporotic vertebral compression fractures in Europe.

METHODS

Systematic review of the literature, until September 2013, and meta-analysis of randomized controlled trials performed in Europe assessing the safety of balloon kyphoplasty in patients with symptomatic osteoporotic vertebral fractures. Outcomes sought include cement leaks, serious clinical complications and new vertebral fractures.

RESULTS

Six randomized controlled trials fulfilled the inclusion criteria. These studies included data on 525 treated levels in 424 patients. Cement leakages were detected in 18.3 % (95 % CI 11.6, 23.0) of fractures intervened. In about 0.5 % (95 % CI 0.1, 1.1) of fractures leakages proved to be symptomatic. Serious clinical complications were recorded in 11.5 % (95 % CI 1.1, 21.7) of patients treated with balloon kyphoplasty with several of these cases requiring intensive treatment or postoperative surgery. New vertebral fractures were detected in 20.7 % (95 % CI 0.4, 40.9) of patients treated but rates showed an upward pattern when the follow-up period increased. In 54 % of such cases, the fractures were located in regions adjacent to the treated level.

CONCLUSIONS

The safety profile and associated complications of balloon kyphoplasty shown in this analysis, based on the evidence provided by existing randomized controlled trials, can be of help to the practicing clinician who must contrast them with the potential benefits of the technique. These data represent an important step towards a balanced evaluation of the intervention though, a better reporting and more reliable data on long-term assessment of potential sequelae are needed.

Lumbar Nerve Root Compression due to Leakage of Bone Cement after Vertebroplasty

We experienced a 73-year-old male with lumbar nerve root compression due to leakage of bone cement after vertebroplasty. He was underwent vertebroplasty for acute osteoporotic L4 compression fracture at our hospital. After vertebroplasty, his back pain was improved but right leg pain was newly developed. Lumbar computed tomography scanning showed that bone cements were leaked along the L4 nerve root. The leaked cements around L4 nerve root were removed carefully via paraspinal muscle-splitting approach. After operation, severe right leg radiating pain was improved. We recommend proper entry point, high viscosity of polymethylmethacrylate and constant monitoring can reduce complication.

Should we fear cement leakage during kyphoplasty in percutaneous traumatic spine surgery? A single experience with 76 consecutive cases

OBJECTIVE

Although kyphoplasty is widely used to repair osteoporotic and pathologic vertebral fractures, balloon kyphoplasty and vertebral body stenting are new treatment options in cases of traumatic spinal injury. To our knowledge, there are no literature data on the incidence of cement leakage whereas these two percutaneous techniques are commonly used to repair non-pathologic fractures. The aim of this study was to evaluate and compare the clinical characteristics and the incidence of cement leakage associated with balloon kyphoplasty and vertebral body stenting in the percutaneous treatment of traumatic spinal injury.

METHODS

A series of 76 consecutive kyphoplasties (50 with vertebral body stenting and 26 balloon kyphoplasties) were retrospectively reviewed. Preoperative and postoperative computed tomography scans were analyzed in order to detect cement leakage and grade it as minor, moderate or major.

RESULTS

The overall leakage rate was 50%. None of the leakages gave rise to clinical symptoms. Although balloon kyphoplasty and vertebral body stenting did not differ in terms of the leakage rate, the latter technique was associated with a lower leakage volume. The Magerl type, fracture level and use of concomitant osteosynthesis did not appear to significantly influence the leakage rate.

CONCLUSION

Vertebral body stenting can reduce the amount of cement leakage due to a better cohesion of the bone fragments after kyphosis correction and maintenance.

Unilateral versus bilateral balloon kyphoplasty in the treatment of osteoporotic vertebral compression fractures

Bilateral and unilateral approaches are the main methods for balloon kyphoplasty. However, controversy exists about which leads to superior outcomes. The goal of this study was to compare the clinical effects and safety of unilateral vs bilateral balloon kyphoplasty for osteoporotic vertebral compression fractures. Five databases (PubMed, Cochrane Library, EMBASE, Web of Science, and Chinese Biomedical Database) were searched without language, publication, or date restrictions. Randomized controlled trials involving a total of 876 patients and comparing the efficacy of unilateral vs bilateral balloon kyphoplasty for osteoporotic vertebral compression fractures were identified. Meta-analysis revealed no significant differences in visual analog scale pain score up to 2-year follow-up (mean difference at 1 week, 0.17 [95% confidence interval (CI), -0.11 to 0.44]; mean difference at 1 year, 0.01 [95% CI, -0.29 to 0.32]; mean difference at 2 years, 0.28 [95% CI, -0.13 to 0.70]), Oswestry Disability Index pain score up to 1-year follow-up (mean difference at 1 week, 1.28 [95% CI, -2.62 to 5.17]; mean difference at 1 year, 1.87 (95% CI, -5.33 to 9.06]), anterior and middle vertebral height (mean difference anterior, -0.13 [95% CI, -0.32 to 0.06]; mean difference middle, -0.16 [95% CI, -0.36 to 0.03]), or kyphotic angle (mean difference, -0.02 [95% CI, -0.65 to 0.61]); however, the unilateral approach resulted in a shorter operative time (mean difference, -19.33 [95% CI, -4.42 to -14.24]), smaller amount of cement injected (mean difference, -2.07 [95% CI, -2.42 to -1.71]), and lower risk of cement leakage (mean difference, 0.47 [95% CI, 0.24-0.92]) than the bilateral approach. The unilateral approach resulted in pain relief and vertebral height and kyphotic angle restoration comparable with that of bilateral kyphoplasty. The unilateral approach should be considered an effective option for the treatment of osteoporotic vertebral compression fractures.

Real-life results of balloon kyphoplasty for vertebral compression fractures from the SWISSspine registry

BACKGROUND CONTEXT

The Swiss Federal Office of Public Health mandated a nationwide health technology assessment-registry for balloon kyphoplasty (BKP) for decision making on reimbursement of these interventions. The early results of the registry led to a permanent coverage of BKP by basic health insurance. The documentation was continued for further evidence generation.

PURPOSE

This analysis reports on the 1 year results of patients after BKP treatment.

STUDY DESIGN

Prospective multicenter observational case series.

PATIENT SAMPLE

The data on 625 cases with 819 treated vertebrae were documented from March 2005 to May 2012.

OUTCOME MEASURES

Surgeon-administered outcome instruments were primary intervention form for BKP and the follow-up form; patient self-reported measures were EuroQol-5D questionnaire, North American Spine Society outcome instrument /Core Outcome Measures Index (including visual analog scale), and a comorbidity questionnaire. Outcome measures were back pain, medication, quality of life (QoL), cement extrusions, and new fractures within the first postoperative year.

METHODS

Data were recorded preoperatively and at 3 to 6-month and 1-year follow-ups. Wilcoxon signed-rank test was used for comparison of pre- with postoperative measurements. Multivariate logistic regression was used to identify factors with a significant influence on the outcome.

RESULTS

Seventy percent of patients were women with mean age of 71 years (range, 18-91 years); mean age of men was 65 years (range, 15-93 years). Significant and clinically relevant reduction of back pain, improvement of QoL, and reduction of pain killer consumption was seen within the first postoperative year. Preoperative back pain decreased from 69.3 to 29.0 at 3 to 6-month and remained unchanged at 1-year follow-ups. Consequently, QoL improved from 0.23 to 0.71 and 0.75 at the same follow-up intervals. The overall vertebra-based cement extrusion rates with and without extrusions into intervertebral discs were 22.1% and 15.3%, respectively. Symptomatic cement extrusions with radiculopathy were five (0.8%). A new vertebral fracture within a year from the BKP surgery was observed in 18.4% of the patients.

CONCLUSIONS

The results of the largest observational study for BKP so far are consistent with published randomized trials and systematic reviews. In this routine health care setting, BKP is safe and effective in reducing pain, improving QoL, and lowering pain_killer consumption and has an acceptable rate of cement extrusions. Postoperative outcome results show clear and significant clinical improvement at early follow-up that remain stable during the first postoperative year.

Basivertebral foramen could be connected with intravertebral cleft: a potential risk factor of cement leakage in percutaneous kyphoplasty

BACKGROUND CONTEXT

Among different types of cement leakage in percutaneous kyphoplasty (PKP) for osteoporotic vertebral body compression fractures, leaks into the spinal canal are considered to be the most common complication. One potential structure causing this type of cement leakage is the potential connection between the basivertebral foramen and the intravertebral cleft, which is revealed clearly on magnetic resonance (MR) images, but is often ignored in the literature.

PURPOSE

The purpose of this study is to assess the incidence rate of different types of cement leakage in PKP with or without intravertebral clefts and to determine whether the basivertebral foramen could be connected to the intravertebral cleft.

STUDY DESIGN

This study is a retrospective assessment of the presence of an intravertebral cleft in osteoporotic vertebral bodies and the different types of cement leakage after PKP on radiographs, computed tomographic (CT) scans, and MR images.

PATIENT SAMPLE

A total of 164 consecutive patients underwent PKP to treat 204 osteoporotic vertebral compression fractures.

OUTCOME MEASURES

Outcome measures include the occurrence of different types of cement leakage in the groups with an intravertebral cleft and without intravertebral clefts.

METHODS

A total of 204 vertebrae in 164 consecutive patients who underwent PKP to treat osteoporotic vertebral compression fractures were classified into two patterns based on preoperative radiographs, CT scans, and/or MR images of the treated levels: cleft pattern (with an intravertebral cleft in the vertebral body) and trabecular pattern (without intravertebral clefts). When an intravertebral cleft was identified, the investigators examined the basivertebral foramen and looked for a communication between the two structures on three-dimensional CT scans and MR images. On direct postoperative images, the patterns of cement leakage were classified as five types: type A, through a cortical defect into the paraspinal soft tissues; type B, through the basivertebral foramen; type C, via the needle channel; type D, through a cortical defect into the disc space; and type E, via the paravertebral vein. The association of the distribution of the cement leakage and the presence of an intravertebral cleft was analyzed retrospectively. Moreover, the association of type B leakage with the communication between the basivertebral foramen and the intravertebral cleft was also assessed.

RESULTS

The average interobserver kappa values for determining the type of cement leakage and the presence of intravertebral cleft were 0.916 (range, 0.792-1) and 0.935, respectively. In 41 of 204 vertebrae (19.9%), an intravertebral cleft was confirmed on preoperative images. A communication between the intravertebral cleft and the basivertebral foramen was seen in 10 vertebrae (24.4%). Cement leakage was 36.2% in the group with a trabecular pattern and 41.5% in the group with a cleft pattern (p>.05). Leaks through the basivertebral foramen (type B; N=30, 14.7%) and through cortical defects into the disc space (type D; N=14, 6.9%) were more common than other types. Twenty of 163 vertebrae with the trabecular pattern (12.3%) and 10 of 41 vertebrae with the cleft pattern (24.4%) were identified as type B leaks, which reached statistical significance (p<.05). There was no statistical difference between the trabecular pattern and the cleft pattern on other types of leaks.

CONCLUSIONS

Type B leaks are more common in vertebrae with an intravertebral cleft, which supports the presence of a connection between an intravertebral cleft and the basivertebral foramen. Thus, care must be taken when PKP is performed in these patients to avoid direct cement leakage into the spinal canal through the basivertebral foramen.

Vertebroplasty

Percutaneous vertebroplasty has become widely accepted as a safe and effective minimally invasive procedure for the treatment of painful vertebral body compression fractures refractory to medical therapy. In this article, the authors review the indications and contraindications for vertebroplasty, principles of appropriate patient selection, useful techniques to achieve optimal outcomes, and the potential risks and complications of the procedure.

Risks and benefits of percutaneous vertebroplasty or kyphoplasty in the management of osteoporotic vertebral fractures

Vertebral fracture (VF) is the most common osteoporotic fracture and is associated with high morbidity and mortality. Conservative treatment combining antalgic agents and rest is usually recommended for symptomatic VFs. The aim of this paper is to review the randomized controlled trials comparing the efficacy and safety of percutaneous vertebroplasty (VP) and percutaneous balloon kyphoplasty (KP) versus conservative treatment. VP and KP procedures are associated with an acceptable general safety. Although the case series investigating VP/KP have all shown an outstanding analgesic benefit, randomized controlled studies are rare and have yielded contradictory results. In several of these studies, a short-term analgesic benefit was observed, except in the prospective randomized sham-controlled studies. A long-term analgesic and functional benefit has rarely been noted. Several recent studies have shown that both VP and KP are associated with an increased risk of new VFs. These fractures are mostly VFs adjacent to the procedure, and they occur within a shorter time period than VFs in other locations. The main risk factors include the number of preexisting VFs, the number of VPs/KPs performed, age, decreased bone mineral density, and intradiscal cement leakage. It is therefore important to involve the patients to whom VP/KP is being proposed in the decision-making process. It is also essential to rapidly initiate a specific osteoporosis therapy when a VF occurs (ideally a bone anabolic treatment) so as to reduce the risk of fracture. Randomized controlled studies are necessary in order to better define the profile of patients who likely benefit the most from VP/KP.

Epidural and intradural cement leakage following percutaneous vertebroplasty: a case report

A 48-year-old woman presented with severe bilateral leg pain, urinary incontinence, and paraparesis following vertebroplasty in another hospital 15 days earlier. Computed tomography and magnetic resonance imaging showed blocks of epidural and intradural cement from T12 to L1 with neurological compression. She underwent corpectomy of L1 and removal of extradural cement, followed by anterior reconstruction with an expandable cage and dual rodscrew construct (Kaneda system). Postoperatively, the patient had minimal improvement in leg pain and neurological deficit. Computed tomographic myelography was therefore performed and revealed complete blockage, which is suspected to be due to intradural cement leakage. The patient underwent posterior durotomy and removal of the cement. Postoperatively, the patient reported immediate pain relief. Her neurological status gradually improved over months. At the 2-year follow-up, the patient was able to walk with support and to perform activities of daily living and had regained her urinary function.

Effect of vertebroplasty on the compressive strength of vertebral bodies

BACKGROUND CONTEXT

Percutaneous vertebroplasty has been used successfully for many years in the treatment of painful compressive vertebral fractures due to osteoporosis.

PURPOSE

To compare the effect of vertebroplasty on the compressive strength of unfractured vertebral bodies.

STUDY DESIGN

Biomechanical study on cadaveric thoracic vertebrae.

METHODS

Forty vertebral bodies from four cadaveric thoracic spines were used for this experiment. Before testing, each thoracic spine was submitted to bone density testing and radiographic evaluation to rule out any obvious fractures. Under image intensification, 6 mL of a mixture of polymethylmethacrylate (PMMA) with barium (8 g of barium/40 g of PMMA) was injected into every other vertebral body of each spine specimen. After vertebroplasty, all soft tissues were dissected from the spine, and the vertebral bodies were separated and potted for mechanical testing. Testing to failure was performed using a combination of axial compression and anterior flexion moments. Two pneumatic cylinders applied anterior and posterior loads at a distance ratio of 4:3 relative to the anterior vertebral body wall, whereas two additional cylinders applied lateral loads, each at a constant rate of 200 N/s.

RESULTS

The average failure loads for nonvertebroplasty specimens was 6724.02 ± 3291.70 N, whereas the specimens injected with PMMA failed at an average compressive force of 5770.50 ± 2133.72 N. No statistically significant difference in failure loads could be detected between intact specimens and those that had undergone vertebroplasty.

CONCLUSIONS

Under these specific loading conditions, no significant increase in compressive strength of the vertebral bodies could be documented. This suggests that some caution should be applied to the concept of "prophylactic" vertebroplasty in patients at risk for fracture.

Biomechanical characteristics of cement/gelatin mixture for prevention of cement leakage in vertebral augmentation

PURPOSE

This study evaluated whether or not the addition of gelatin micro-particles into the polymethyl methacrylate (PMMA) could reduce cement infiltration in cancellous bone of vertebra.

METHODS

Gelatin micro-particles were prepared in various sizes and mixed with PMMA in different densities. Dynamic viscosity of the mixture was measured by a rotational rheometer. Fresh bovine vertebral bodies were sectioned into cylindrical samples. Permeability of the mixture through the samples was tested on a mechanical test machine, and calculated using Darcy's law. The PMMA/gelatin mixture also underwent compressive and bending tests, and their structures were examined by scanning electron microscopy.

RESULTS

The cement/gelatin mixture increased the viscosity. Significant reduction of cement permeability in cancellous bone was determined after the addition of the micro-particles. Micro-particles of 2 % in density and 125-250 μm in size decreased the permeability by 1/3 without any significant change of the cement viscosity. The biomechanical strength was unchanged in compression but decreased by up to 20 % in bending.

CONCLUSIONS

Gelatin micro-particles significantly increased the cement viscosity, reduced the permeability in cancellous bone of vertebra, decreased the flexural strength, but did not affect the compressive strength. Although it suggested a manageable approach in vertebral augmentation, the outcome should be further verified on a cadaveric model or an animal model before the mixture could be used safely and effectively in the clinical treatment.