Clinical Outcomes of Vertebroplasty or Kyphoplasty for Patients With Vertebral Compression Fractures: A Nationwide Cohort Study

Spinal medial branch nerve root block (MBNB) intervention compared to standard care-vertebroplasty (VP) for the treatment of painful osteoporotic vertebral fractures in frail, older hospitalised patients: a feasibility study

Our study aimed to assess the feasibility outcomes comparing spinal medial branch nerve root block intervention to standard care vertebroplasty for the treatment of painful osteoporotic vertebral fractures in frail, hospitalised older patients. We found the study to be feasible and now propose a clinical effectiveness, cost effectiveness and safety evaluation.

INTRODUCTION

Vertebroplasty (VP) is a key-hole procedure involving injection of bone cement into a fractured vertebral body, to reduce pain and increase vertebral body stability, although it is associated with a small risk of complications, particularly in frail, older hospitalised patients. Medial branch spinal nerve block (MBNB) may be an alternative treatment to alleviate pain symptoms, with less complications; however, no study has prospectively compared the clinical effectiveness, cost-effectiveness and safety of MBNB to VP, in frail, older hospitalised patients. The aim of our study was to conduct a 1st stage feasibility study, exploring recruitment, retention and several outcomes measures (means and SDs), together with qualitative interviews to assess participant and clinician views, to inform a definitive larger study.

METHODS

We conducted a two-arm feasibility randomised controlled trial with participants allocated to continue with routine surgical care-VP or MBNB treatment, with an embedded qualitative study. Data was collected at baseline, week 1, 4, and week 8.

RESULTS

Out of 40 eligible patients, 30 (75%) consented to take part in the study. The overall median time from randomisation to intervention was 3 days, IQR 1-7 days, 5 (1-7) days for VP and 2 (1-3) days for MBNB. Median (IQR) length of hospital stay for the VP group was 20 (8) days and for the MBNB 15(22) days. The proportion of completeness of outcome data collection at weeks 1, 4 and 8 was at least 77%: 14 (100%), 12 (85.7%) and 11(78.9%) for VP and 13 (100%), 12 (92.3%) and 10 (76.8%) for MBNB, respectively. There were no significant difference in the clinical outcomes or adverse events between the two groups.

DISCUSSION

Our study was feasible in achieving is target recruitment, participants adhered to the randomisation and at least 77% completeness of data at the 8 week end-point (target 75%). We now plan to conduct a definitive clinical effectiveness, cost effectiveness and safety outcome study, comparing VP to MBNB in frail, older patients hospitalised with an acute vertebral osteoporotic fracture.

A 3-year retrospective analysis of patients admitted with clinical vertebral fragility fractures across hospitals in England, UK

Our database aimed to assess the impact of vertebral fragility fractures (VFFs) on hospitalisation in England. The results showed that admissions secondary to VFF are increasing annually, more significantly in patients aged 75 years and over. Vertebral augmentation has been showed to reduce length of stay in hospital.

INTRODUCTION

Vertebral fragility fractures (VFFs) are the most common osteoporotic fracture. VFF can result in significant pain requiring hospitalisation. However, there are little data on patient numbers, hospital bed days, and costs, contributed to by these patients.

METHODOLOGY

We report a retrospective analysis of patients aged 55 years and over admitted to hospitals across England from 2017 to 2019. ICD-10 classifications for VFF and OPCS codes were used to identify admissions and patients who had undergone vertebral augmentation (VA).

RESULTS

There were 99,370 patients (61% female) admitted during this period, with 64,370 (65%) patients aged over 75 years. There was a 14.3% average increase in admissions annually. Patients aged over 75 years accounted for 1.5 million bed days, costing £465 million (median length of stay (MLOS) 14.4 days). In comparison, those aged 55-74 years, accounted for 659,000 bed days, costing £239 million (MLOS 10.7 days). The majority of patients (84%) were admitted under a non-surgical speciality and were primarily older (median age 76.8 vs 67.6 years, MLOS 8.2 vs 6.0 days), compared to those admitted to surgical wards 1755 patients underwent vertebral augmentation (VA) (1.8% of the total cohort). The median age of patients undergoing VA was 73.3 years, with 775 (44.2%) of these were aged 75 years and over. In comparison, the median age of patients managed conservatively (non-surgically) was 75.7 years, with 63,595 patients (65.1%) aged 75 years and over. The MLOS and cost per patient admission were lower in the VA group compared to those managed non-surgically.

CONCLUSION

Hospitalised VFF patients represented a significant number, cost, and use of bed days. Those undergoing VA had a significantly shorter length of stay. Further studies are necessary to define those who may benefit from early VA.

Effect of Surgical Timing on the Refracture Rate after Percutaneous Vertebroplasty: A Retrospective Analysis of at Least 4-Year Follow-Up

Introduction

The effect of surgical timing on vertebral refracture rate and mortality remains elusive after percutaneous kyphoplasty (PKP) or percutaneous vertebroplasty (PVP), and we aim to assess the impact of surgical timing on vertebral refracture rate and mortality in patients undergoing percutaneous vertebroplasty.

Methods

We did a retrospective cohort study of patients who underwent PKP or PVP because of osteoporotic vertebral compression fracture (OVCF) between April 1, 2014 and March 31, 2016. The primary outcome measure was the incidence of vertebral refracture. Secondary outcomes included the mortality and chronic back pain.

Results

The rate of vertebral refracture was significantly lower in early surgical timing group than that in late surgical timing group (HR 2.415, 95% CI 1.318–4.427; P = 0.004). We found that the bone mineral density (BMD) was only the risk factor to increase the vertebral refracture rate after vertebroplasty (P = 0.001). In addition, there was similar mortality between the two groups (15.7% in early surgical timing group versus 10% in late surgical timing group). Male patients (27.3%, 12/44) had higher mortality compared to female patients (10.6%, 20/189), while the mortality was higher in patients with cerebral infarction (25%, 3/12) than those without cerebral infarction (12.1%, 17/140).

Conclusions

Surgical timing significantly affects the vertebral refracture rate after PKP or PVP, which is also influenced by BMD. The mortality after the surgery is not affected by the surgical timing, but gender and cerebral infarction may be the risk factors of mortality.

The evidentiary basis of vertebral augmentation: a 2019 update

No aspect of neurointerventional practice has been associated with as longstanding contention and debate as to its effectiveness as has vertebroplasty (VP). Four blinded randomized controlled trials published since 2009 have demonstrated conflicting results regarding a conferred benefit in pain reduction and functional improvement for patients who undergo VP for osteoporotic vertebral compression fractures. Significant heterogeneity exists between each of these trials, which has resulted in difficulty for interventionalists and surgeons to translate the trial findings into routine clinical practice. In addition, patients and their families are ever more enlightened and enabled via the internet and social media to review both medical literature and websites. Without the proper background and context, their decisions may be lacking appropriate and necessary scientific discussion. This review article summarizes the randomized controlled trial data to date, with particular focus on the aforementioned four blinded studies. We will also evaluate the profound impact of the decrease in vertebral augmentation utilization on short- and long-term patient morbidity and mortality using available national and administrative datasets from both within the USA and internationally. We also consider future trial design to help evaluate this procedure and determine its role in modern neurointerventional practice.

Osteogenesis enhancement of silk fibroin/ α-TCP cement by N-acetyl cysteine through Wnt/β-catenin signaling pathway in vivo and vitro

High brittleness and lack osteogenesis are two major limitations of calcium phosphate cement (CPC) in application in bone defect reconstruction. Here we prepared a composite calcium phosphate cement by mixing N-acetyl cysteine loaded silk fibroin solution with α-tricalcium phosphate. In vitro cytology experiment revealed that SF-NAC/α-TCP could significantly increase the activity of exocrine ALP and up-regulated expression of bone-related genes. However, NAC up-regulated gene expression could be significantly suppressed by DKK1. We propose that NAC functioning as osteogenic factor by activating the Wnt/β-catenin signaling pathway may be the possible mechanism of up-regulation of osteogenic genes. Bone regeneration in vivo shown in a rat femur defect was enhanced by the addition of NAC in SF/α-TCP. In addition, the combination intensity of cement-bone interface was improved. The combination SF-NAC/α-TCP might be developed into a promising tool for bone tissue repair in the clinic.

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.

30-Day unplanned surgery in cervical spondylotic myelopathy surgically treated: a single-center experience

STUDY DESIGN

Retrospective cohort study.

OBJECTIVE

Analyze the rate and risk factors associated with Unplanned Surgeries (US) during the first 30 days in patients treated for cervical spondylotic myelopathy.

BACKGROUND

US are often regarded as a potentially useful quality of care indicator.

METHODS

We defined US as any, non-planned, surgical procedure as a complication after "index" surgery. Demographic data, comorbidities, ASA, smoking status, surgical details and postoperative complications were collected. We conducted a subjective outcome test using the Global Outcome Score (GOS). To assess risk factors, a bivariate analysis was performed using T Student or Chi-square. Risk is shown as odds ratio (OR) with 95% confidence interval (CI). Multivariable logistic regression models with bootstrap resampling procedure were performed.
 RESULTS: The study included 303 patients (200 men) with mean age of 57.7 years (27-86) and mean follow-up of 75.35 months (16-126 m). 63.3% patients were ASA 1 or 2 and 41.9% were smokers. 77.9% of patients had some comorbidity. Anterior approach surgeries were 65.7%. Perioperative complications: 29% medical, 8.9% intraoperative and 3% implant related. US rate was 2.6%. Causes for revision were postoperative infection or deep hematomas. After bivariate analysis, the risk factors associated were diabetes mellitus (OR 2.6; 95% CI 1-5.5) and intraoperative complications (OR 6.5, 95% CI 1-40). The presence of US does not have influence in satisfaction using GOS score.

CONCLUSIONS

Our US rate was 2.6%, similar to the literature. Diabetics and patients suffering an intraoperative complication are more likely to need an early reinterventions (OR 2.2 and 6.5, respectively). US did not alter the patient's outcomes. These slides can be retrieved under Electronic Supplementary Material.

Vertebroplasty and Kyphoplasty for Osteoporotic Vertebral Fractures: What Are the Latest Data?

Osteoporotic vertebral compression fractures frequently result in significant morbidity and health care resource use. For patients with severe and disabling pain, vertebral augmentation (vertebroplasty and kyphoplasty) is often considered. Although vertebroplasty was introduced >30 years ago, there are conflicting opinions regarding the role of these procedures in the treatment of osteoporotic vertebral compression fractures. This review article updates clinicians on the published prospective randomized controlled data, including the most recent positive trials that followed initial negative trials in 2009. Analysis of multiple national claim datasets has also provided further insight into the utility of these procedures. Finally, we considered the recent recommendations of national organizations and medical societies that advise on the use of vertebral augmentation procedures for osteoporotic vertebral compression fractures.

Progression of Vertebral Compression Fractures After Previous Vertebral Augmentation: Technical Reasons for Recurrent Fractures in a Previously Treated Vertebra

It is well recognized that patients can develop additional vertebral compression fractures (VCF) in an adjacent vertebra or at another vertebral level after successful vertebral augmentation. Factors such as the patient's bone mineral density, post procedure activity, and chronic corticosteroid use contribute to an increased risk of re-fracture or development of new fractures in the first three months after the initial procedure. However, there is a very small subgroup of patients that have unchanged or worse pain after the vertebral augmentation that may indicate continued progression of the treated compression fracture or a recurrent fracture at the previously treated level. This review examines the clinical findings, radiologic signs, and intraprocedural technical failures that may occur during the initial vertebral augmentation that can lead to a progressive fracture in a previously treated vertebra. Causes of failure of the initial vertebral augmentation procedure include inadequate or incomplete filling of the fracture site, the cement missing the actual fracture allowing continued osteoporotic compression, and persistent or worsened intravertebral fluid-filled clefts. The existence of an unfilled intravertebral fluid cleft on preoperative diagnostic studies is the most important indicator of risk for progression as is the later development of fluid at the bone cement interface.

Risk factors for hospital re-presentation among older adults following fragility fractures: a systematic review and meta-analysis

BACKGROUND

Older adults hospitalized with fragility fractures are at high risk of negative events that can culminate in re-presentations to hospital emergency departments or readmissions to hospital. This systematic review aimed to identify patient, clinical, or hospital-related factors that are identifiable at the index admission and that may be associated with re-presentations to hospital emergency departments or hospital readmissions in older adults following fragility fractures.

METHODS

Four electronic databases (PubMed, CINAHL, Embase, and Scopus) were searched. A suite of search terms identified peer-reviewed English-language articles that examined potential correlates of hospital re-presentation in older adults (mean age ≥ 65 years) who were discharged from hospital following treatment for fragility fractures. A three-stage screening process (titles, abstracts, full text) was conducted by two researchers independently. Participant characteristics, study design, potential correlates examined, analyses, and findings were extracted for studies included in the review. Quality and risk of bias were assessed with the Effective Public Health Practice Project Quality Assessment Tool. The strength of evidence was incorporated into a best evidence synthesis, and meta-analysis was conducted where effect pooling was possible.

RESULTS

Eleven of 35 eligible studies were categorized as high quality studies. These studies reported that age, higher Cumulative Illness Rating scores, American Society of Anesthesiologists scores > 3, longer length of stay, male sex, cardiovascular disease, low post-operative hemoglobin, kidney disease, dementia and cancer were factors identified at the index admission that were predictive of subsequent re-presentation to hospital. Age was the only predictor for which pooling of effects across studies was possible: pooling was conducted for re-presentation ≤ 30 days (pooled OR, 1.27; 95 % CI, 1.14-1.43) and > 30 days (pooled OR, 1.23; 95 % CI, 1.01-1.50).

CONCLUSIONS

The best-evidence synthesis, in addition to the meta-analysis, identified a range of factors that may have utility in guiding clinical practice and policy guidelines for targeted interventions to reduce the need for re-presentation to hospital among this frail clinical population. The paucity of studies investigating re-presentations to hospital emergency departments without admission was an important gap in the literature identified in this review. Key limitations were exclusion of non-English language studies and grey literature.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42015019379 .

Results of Vertebral Augmentation Treatment for Patients of Painful Osteoporotic Vertebral Compression Fractures: A Meta-Analysis of Eight Randomized Controlled Trials

Background

In 2009 two RCTs were publicated to question the efficacy of vertebroplasty comparing with sham treatment (ST) in the New England Journal of Medicine (NEJM), which provoked an academic debate on the efficacy of PVA. The purposes of our study were to compare clinical differences in pain relief, spinal functional outcomes, and overall quality of life between PVA and CT for painful osteoporotic VCFs.

Methods

We searched PubMed, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials and Web of Knowledge from January 1980 to June 2013 with Medical Subject Headings terms and keywords. Risk of bias in the included studies was assessed in accordance with the Cochrane risk of bias tool. In this Meta-analysis dichotomous and continuous variables were calculated using the risk ratio (RR) and standardized mean difference (SMD), respectively.

Results

Eight studies involving 987 patients met the criteria for inclusion. The VAS SMD was favoring the experimental group significantly (p < 0.001). Subgroup analysis suggested that the patients performed PVA with mean fracture age less than 3 months would got pain relief earlier and more durable than the control group (P <0.05). The SMD of spinal function assessed with RDQ and Oswestry LBP data was in favor of the experimental groups. QOL outcome improvement was demonstrated statistically significant at early, middle and late-term follow-up for PVA than the control group (P <0.05).

Conclusions

In conclusion, this meta-analysis, which evaluated PVA for osteoporotic VCFs, demonstrated significant improvement regarding VAS, spinal function and QOL outcomes. The optimal fracture age was less than 12 weeks.

Short-segment posterior instrumentation combined with calcium sulfate cement vertebroplasty for thoracolumbar compression fractures: radiographic outcomes including nonunion and other complications

OBJECTIVE

To evaluate the radiographic outcomes of short-segment posterior instrumentation plus vertebroplasty using injectable calcium sulfate cement (CSC) for thoracolumbar compression fractures.

MATERIALS AND METHODS

Twenty-eight patients with a single-level thoracolumbar compression fracture, who underwent short-segment pedicle screw fixation and CSC vertebroplasty, were included in the study. The anterior vertebral body height ratio, local kyphosis angle, and the height of the intervertebral disc adjacent to the fractured vertebra were used to evaluate the radiographic results. Complications including bone nonunion, instrument failure, cement leakage, and disc vacuum formation were also assessed.

RESULTS

The patients were followed up for an average of 24.20±5.40 months. The relative preoperative anterior body height was 55.71±15.29%, which improved to 94.93±5.39% immediately after surgery (P<0.001), and at final follow-up showed a 6.50±3.89% loss of height correction (P<0.001). The mean preoperative local kyphosis angle was 22.23±5.65°, which corrected to 2.67±4.43° immediately after surgery (P<0.001), but reverted to 6.71±4.95° at final follow-up, showing a 4.04±1.91° loss of correction (P<0.001). The mean height of the intervertebral disc proximal to the fractured vertebra was 9.87±0.91 mm before surgery, 12.53±0.98 mm after operation (P<0.001), and the loss of correction at final follow-up was 2.35±1.15 mm with a significant difference compared to immediate postoperative values (P<0.001). Bone nonunion occurred in 7 patients, 2 patients had hardware failure, 9 patients had cement leakage, and 10 patients had disc vacuum phenomenon adjacent to the fractured vertebra.

CONCLUSIONS

The patients who underwent this procedure had a loss of correction of vertebral height and local kyphosis. Complications such as bone nonunion, instrument failure, cement leakage, and disc vacuum may occur. Rapid CSC resorption accounts for these radiographic outcomes and complications.

LEVEL OF EVIDENCE

Level IV, retrospective study.

Repeated vertebral augmentation for new vertebral compression fractures of postvertebral augmentation patients: a nationwide cohort study

Purpose

Postvertebral augmentation vertebral compression fractures are common; repeated vertebral augmentation is usually performed for prompt pain relief. This study aimed to evaluate the incidence and risk factors of repeat vertebral augmentation.

Methods

We performed a retrospective, nationwide, population-based longitudinal observation study, using the National Health Insurance Research Database (NHIRD) of Taiwan. All patients who received vertebral augmentation for vertebral compression fractures were evaluated. The collected data included patient characteristics (demographics, comorbidities, and medication exposure) and repeat vertebral augmentation. Kaplan–Meier and stratified Cox proportional hazard regressions were performed for analyses.

Results

The overall incidence of repeat vertebral augmentation was 11.3% during the follow-up until 2010. Patients with the following characteristics were at greater risk for repeat vertebral augmentation: female sex (AOR=1.24; 95% confidence interval [CI]: 1.10–2.36), advanced age (AOR=1.60; 95% CI: 1.32–2.08), diabetes mellitus (AOR=4.31; 95% CI: 4.05–5.88), cerebrovascular disease (AOR=4.09; 95% CI: 3.44–5.76), dementia (AOR=1.97; 95% CI: 1.69–2.33), blindness or low vision (AOR=3.72; 95% CI: 2.32–3.95), hypertension (AOR=2.58; 95% CI: 2.35–3.47), and hyperlipidemia (AOR=2.09; 95% CI: 1.67–2.22). Patients taking calcium/vitamin D (AOR=2.98; 95% CI: 1.83–3.93), bisphosphonates (AOR=2.11; 95% CI: 1.26–2.61), or calcitonin (AOR=4.59; 95% CI: 3.40–5.77) were less likely to undergo repeat vertebral augmentation; however, those taking steroids (AOR=7.28; 95% CI: 6.32–8.08), acetaminophen (AOR=3.54; 95% CI: 2.75–4.83), or nonsteroidal anti-inflammatory drugs (NSAIDs) (AOR=6.14; 95% CI: 5.08–7.41) were more likely to undergo repeat vertebral augmentation.

Conclusion

We conclude that the incidence of repeat vertebral augmentation is rather high. An understanding of risk factors predicting repeat vertebral augmentation provides valuable basis to improve health care for geriatric populations.

Applications of memory alloy stent in vertebral fractures

Background

The aim of this study was to evaluate the feasibility of treating vertebral compression fractures using an autonomously developed nitinol memory alloy vertebral stent.

Material/Methods

Thoracolumbar vertebral specimens from adult human cadavers were made into models of compression fractures. The models were divided into group A, which received percutaneous kyphoplasty (PKP), balloon dilation, and nitinol memory alloy vertebral stent implantation (PKP + nitinol stent group); group B, which received percutaneous vertebroplasty (PVP) and direct implantation of a nitinol memory alloy vertebral stent (PVP + nitinol stent group); and group C, which received PKP, balloon dilation, and bone cement vertebroplasty (PKP + polymethylmethacrylate (PMMA) group). Vertebral heights were measured before and after the surgery and the water bath incubation to compare the impact of the 3 different surgical approaches on reducing vertebral compression.

Results

The 3 surgical groups could all significantly restore the heights of compressed vertebral bodies. The vertebral heights of the PKP + nitinol stent group, PVP + nitinol stent group, and PKP + PMMA group were changed from the preoperative levels of (1.59±0.08) cm, (1.68±0.08) cm, and (1.66±0.11) cm to the postoperative levels of (2.00±0.09) cm, (1.87±0.04) cm, and (1.99±0.09) cm, respectively. After the water bath, the vertebral heights of each group were changed to (2.10±0.07) cm, (1.98±0.09) cm, and (2.00±0.10) cm, respectively. Pairwise comparison of the differences between the preoperative and postoperative vertebral heights showed that group A and group B differed significantly (P=0.000); group B and group C differed significantly (P=0.003); and group A and group C had no significant difference (P=0.172). Pairwise comparison of the differences in the vertebral heights before and after the water bath showed that group A and group C differed significantly (P=0.000); group B and group C differed significantly (P=0.000); and group A and group B had no significant difference (P=0.157).

Conclusions

The nitinol memory alloy stents can effectively support and reduce the compression of vertebral endplates and can be used to treat vertebral compression fractures without neurological symptoms.

Controversial issues in kyphoplasty and vertebroplasty in osteoporotic vertebral fractures

Kyphoplasty (KP) and vertebroplasty (VP) have been successfully employed for many years for the treatment of osteoporotic vertebral fractures. The purpose of this review is to resolve the controversial issues raised by the two randomized trials that claimed no difference between VP and SHAM procedure. In particular we compare nonsurgical management (NSM) and KP and VP, in terms of clinical parameters (pain, disability, quality of life, and new fractures), cost-effectiveness, radiological variables (kyphosis correction and vertebral height restoration), and VP versus KP for cement extravasation and complications profile. Cement types and optimal filling are analyzed and technological innovations are presented. Finally unipedicular/bipedicular techniques are compared. Conclusion. VP and KP are superior to NSM in clinical and radiological parameters and probably more cost-effective. KP is superior to VP in sagittal balance improvement and cement leaking. Complications are rare but serious adverse events have been described, so caution should be exerted. Unilateral procedures should be pursued whenever feasible. Upcoming randomized trials (CEEP, OSTEO-6, STIC-2, and VERTOS IV) will provide the missing link.

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.

Cement directed kyphoplasty reduces cement leakage as compared with vertebroplasty: results of a controlled, randomized trial

STUDY DESIGN

A novel randomized, controlled, unblinded clinical trial comparing 2 procedural interventions for painful osteoporotic vertebral compression fractures.

OBJECTIVE

The primary study objective was to evaluate cement leakage for a cement directed kyphoplasty system (CDKS) with anteriorly biased cement flow and vertebroplasty. The secondary study objective was to compare adjacent level fracture rates and vertebral body height for these 2 intervention methods.

SUMMARY OF BACKGROUND DATA

Cement leakage remains a significant clinical problem associated with vertebroplasty and kyphoplasty procedures. Uncontrolled cement flow in the posterior direction can result in leakage into the vertebral veins or spinal canal, leading to potentially serious clinical complications.

METHODS

Seventy-seven patients with painful osteoporotic vertebral compression fractures were enrolled. Patients were randomized 2:1 for treatment with CDKS (49 patients, 65 levels) or vertebroplasty (28 patients, 39 levels). Cement leakage was evaluated from radiographs and computed tomographic scans. Three- and 12-month follow-ups included additional radiographs and computed tomographic scans to assess changes in vertebral body height and the incidence of new fractures.

RESULTS

Treatment with CDKS significantly reduced the number of levels with leaks and the total number of leaks per level, as compared with vertebroplasty (P = 0.0132 and P = 0.0012, respectively). Significantly, fewer lateral cortical and spinal canal leaks (posterior leaks) occurred in the CDKS group (P = 0.0050, P = 0.02260, respectively). Three adjacent level fractures occurred in the vertebroplasty group, as compared with 2 in the CDKS group. Vertebral body height maintenance was equivalent.

CONCLUSION

Cement directed kyphoplasty effectively reduces posterior cement leakage, reducing the risk of leakage related complications.

LEVEL OF EVIDENCE

2.

Epidemiology of post-transplant malignancy in Asian renal transplant recipients: a population-based study

OBJECTIVE

Using Taiwan's National Health Insurance Research Database, this large population-based study was conducted to explore the incidences and risk factors of post-transplant malignancy in Asian renal transplant recipients.

PATIENTS AND METHODS

A total of 642 patients who firstly underwent renal transplant between January 1, 2000 and December 31, 2008 were identified from a 2 million cohort. The primary endpoint was a subsequent hospitalization with a primary diagnosis of malignancy (ICD-9-CM code: 140.xx-239.xx) after renal transplantation. All patients were followed until the occurrence of endpoints or the end of the study (December 31, 2010), whichever came first. Adjusted risks of post-transplant cancer were analyzed using Cox proportional hazards regression model. All models were adjusted for baseline characteristics, comorbid diseases, transplant year, and exposure to immunosuppressive agents.

RESULTS

Among 642 renal transplant patients, 54 cancers (8.4 %) were identified. The median time between transplant and cancer diagnosis was 46.2 (range 8.5-107.4) months. Cancers of kidney and other unspecified urinary organs was the most common cancer sites, accounted for 18.5 % of the malignancies diagnosed. The next most common cancer sites were trachea, bronchus, and lung (14.8 %), bladder (13.0 %), liver and intrahepatic bile ducts (11.1 %), colon (5.6 %), and prostate (5.6 %). Age at transplantation was a statistically significant risk factor of post-transplant cancer in our study. Increased risks of post-transplant cancer were observed in patients who received immunosuppression agents (cyclosporine (HR 1.26, 95 % CI 0.58-2.77, p = 0.5603), tacrolimus (HR 1.99, 95 % CI 0.66-6.00, p = 0.2197), and mycophenolate (HR 1.00, 95 % CI 0.40-2.45, p = 0.9874)) although the estimates were not statistically significant.

CONCLUSIONS

Our population-based cohort study offers additional insight into post-transplant cancers in Asian population. Further studies are warranted to assess the association between specific immunosuppression agents and post-transplant cancers.