Vertebroplasty and Kyphoplasty

"Double Cross Sign" Could Be an Indicator of an Adequate Amount of Bone Cement in Kyphoplasty with the SpineJack System: A Retrospective Study

Kyphoplasty with the SpineJack system was able to restore vertebral height and stabilize the vertebra with an injection of bone cement. The goal of this study was to seek a reliable assessing method during the surgery in determining the minimum amount of bone cement required for the SpineJack system to restore vertebral height and stabilize the vertebra. We defined the “double cross sign” as bone cement that expanded vertically along the bilateral SpineJack system, and spread across the midline of the vertebral body as viewed in the anteroposterior (AP) view of the radiographic image. Sixty-five patients aged 74.5 ± 8.5 years with vertebral compression fracture were included in the study. Patients with a positive double cross sign had better ODI score than those without the double cross sign (20.0 ± 6.9 vs. 32.3 ± 8.2; p < 0.001). Postoperative regional kyphotic and local kyphotic angle were significantly better in the positive double cross sign group (11 ± 8.8 degrees vs. 5.3 ± 3.2 degrees; p = 0.001/11.7 ± 6.2 degrees vs. 6.6 ± 4.1 degrees; p = 0.001, respectively). The more stable construct was built once the double cross sign was achieved during surgery. In this study, a convenient and intuitive method in identifying the minimum but sufficient quantity of injected cement during the SpineJack procedure was developed.

Resomer C212© in vertebroplasty or kyphoplasty: A feasibility study on artificial bones with biomechanical and thermal evaluation

BACKGROUND

Vertebroplasty and kyphoplasty are now well-established methods for treating compression fractures of vertebral bodies (AO type A) as well as vertebral body metastases [1, 2, 3]. However, polymethylmethacrylate (PMMA) augmented vertebrae show fractures of subsequent vertebral bodies due to the increased stability of the augmented vertebral body [4]. Resorbable cements are currently only used experimentally. Many commercially available resorbable calcium phosphate cements do not exhibit sufficient biomechanical stability to treat vertebral body fractures [5]. Resomer C212© (Evonik Industries AG, Essen, Germany) is a slow resorbable poly-ε-caprolactone that has low melting temperatures and good biomechanical properties.

OBJECTIVE

This is a feasibility study on how the poly-ε-caprolactone Resomer C212© can be used for kypho- or vertebroplasty, what temperatures are used in the argumentation and how differences in load capacity are measurable compared to conventional PMMA cement.

METHODS

23 Sawbones© blocks (7.5 Open Cell Foam, SKU: 1522-09, laminated on both sides, 4 × 4 × 2.9 cm, Sawbones, Vashon Island, USA) were divided into three groups: 7 without augmentation, 8 augmented with PMMA cement Traumacem V+© (DePuy Synthes, West Chester, USA) and 8 augmented with Resomer C212©. Temperature measurements were made in a 37∘C water bath centrally in the block and on the top and bottom plates. This was followed by a maximum load of up to 2000 N using a universal testing machine (Instron E 10000, Instron Industrial Products, Grove City, USA).

RESULTS

In the Resomer C212© test group, the maximum average increase in temperature was 4.15 ± 4.72∘C central, 0.3 ± 0.31∘C at the top and 0.78 ± 1.27∘C at the base. In the cement test group, the average increase in temperature was 9.80 ± 10.65∘C centrally in the test block, 1.50 ± 0.73∘C at the top plate and 1.42 ± 0.66∘C and the base plate. In the axial compression test, the 7 non-kyphoplasted test blocks showed a first loading peak on average at 275.23 ± 80.98 N, a rigidity of 238.47 ± 71.01 N/mm2. In the Traumacem V+© group, the mean peak load was 313.72 ± 46.26 N and rigidity was 353.45 ± 77.23 N/mm2. The Resomer C212© group achieved a peak load of 311.74 ± 52.05 N and a stiffness of 311.30 ± 126.63 N/mm2. A compression to 50% could not be seen in any test block under the load of 2000 N. At 2000 N, Traumacem V+©'s average height reduction was 9.26 ± 2.16 mm and Resomer C212© was 10.93 ± 0.81 mm.

CONCLUSIONS

It has been shown that the application of Resomer C212© in kyphoplasty or vertebroplasty is well feasible. Thermal analysis showed significantly lower temperatures and shorter temperature application in the Resomer C212© group. In the biomechanical load up to 2000 N no significant differences could be observed between the individual groups.

Imaging Improves Efficacy of Vertebroplasty - A Systematic Review and Meta-Analysis

BACKGROUND

Clinical trials with percutaneous vertebral augmentation (PVA) for intractable pain from vertebral compression fractures (VCF) have shown variable results. Variation in the outcomes may be related to poor patient selection on imaging.

OBJECTIVE

To assess if PVA augmentation for osteoporotic VCF results in better improvement in pain when patients were selected based on clinical examination plus imaging vs clinical examination only.

RESULTS

A systematic review and meta-analysis were performed. PubMed, Embase and Cochrane Library databases were searched from 2000 to May 2018. Two reviewers independently screened and extracted data to identify randomised control trials (RCTs) on PVA for osteoporotic VCF and assessed the risk of bias. Standard systematic review and meta-analysis methods were advocated by the Cochrane Collaboration and PRISMA Statement. A total of 12 RCTs with 1110 participants met the inclusion criteria. Eight of the 10 studies (938 participants) that used imaging to confirm oedema in the target vertebral bodies showed PVA (compared to nonsurgical treatment) was effective in reducing pain (immediate term: mean difference (MD) of -1.89; 95% confidence interval -1.93 to -1.85, p < 0.001; short term: MD of -1.68; 95% CI -1.82 to -1.54, p < 0.001; intermediate term: MD of -2.04; 95% CI -2.15 to -1.94, p < 0.001 and long term: MD of -1.88; 95% CI -1.95 to -1.80, p < 0.001).

CONCLUSIONS

RCTs using imaging to confirm marrow oedema in the index vertebra showed an improved size effect compared to RCTs using no imaging. This benefit was observed in the immediate, short, intermediate and long term.

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.

Stentoplasty effectiveness and safety for the treatment of osteoporotic vertebral fractures: a systematic review

To assess the effectiveness and safety of stentoplasty in people with osteoporotic vertebral body fractures. A systematic search of databases including MEDLINE, EMBASE and Cochrane library, between others, was conducted to June 9, 2014. Clinical trials and observational studies that included alive adults with osteoporotic vertebral body fractures and the comparators were the intervention himself, vertebroplasty or balloon kyphoplasty were selected. Quality of evidence was graded according to the GRADE approach. Two review authors independently selected studies, assessed risk of bias and extracted data. Forty-two citations were identified during the search. After removing duplicates, five studies were included: two clinical trials and three observational studies. Stentoplasty, showed higher rate of adverse events related to material (P=0.043) and cuff pressure (P=0.014) in comparison to kyphoplasty. There was no difference between two procedures in terms of reduction of kyphosis, time of exposure to radiation or postoperative loss of cement. Stentoplasty in comparison to vertebroplasty, showed an improvement of restoration of vertebral height (P=0.042), kyphosis correction and volume of bone cement. No differences were found between two procedures in terms of loss of vertebral body volume. Based on observational studies, stentoplasty improved vertebral height, pain and functional disability at 6 and 12months follow-up, and corrected the angle vertebral fractures in patients with osteoporotic vertebral body. Stentoplasty was presented as a safe procedure in short-medium term, with a low complication rate, a reduced loss of cement and new vertebral body fractures lower rates. Stentoplasty improves vertebral height, reduces the pain and functional disability and correct the vertebral angle in patients with osteoporotic vertebral body fracture with minimum adverse events. Stentoplasty is comparable to kyphoplasty in terms of correction of kyphosis, time of exposure to radiation and cement postoperative loss, and comparable to vertebroplasty in terms of restoration of vertebral height correction and bone cement volume.

LEVEL OF EVIDENCE

Level II systematic review.

Trends in pathological vertebral fractures in the United States: 1993 to 2004

OBJECT

Pathological vertebral fractures (PVFs) are an increasingly important cause of disability and have many clinical and economic implications. The authors examined trends in epidemiology and surgical management of pathological vertebral fractures in the US between 1993 and 2004.

METHODS

The Nationwide Inpatient Sample database was used to analyze data collected from 1993 through 2004 to determine general trends in PVFs. Patients with PVFs were identified using the appropriate International Classification of Diseases, 9th Revision (ICD-9) diagnostic code (ICD-9 733.13). Trends in vertebral augmentation procedures and spinal fusions as well as comparison with incidences of other major pathological fractures, such as hip and upper limb, were also examined.

RESULTS

In 2004, there were more than 55,000 inpatient admissions for PVFs. The majority of patients admitted were women (78%) in the 65 to 84 year-age group (60%). Medicare accounted for greater than 80% of insurance, and nearly 50% of all patients were admitted from the emergency department. The mean duration of hospitalization has continued to decrease, from 8.1 days in 1993 to 5.4 days in 2004. The mortality rate has remained relatively constant at approximately 1.5%. The discharge disposition has continued to change with an increasing number of patients being discharged to other institutions such as nursing homes and rehabilitation facilities. There was a staggering increase in the number of vertebral augmentation procedures performed between 1993 and 2004. The "national bill" for inpatient hospitalizations for PVFs totaled $1.3 billion in 2004.

CONCLUSIONS

With the continued aging of the population, PVFs represent an important cause of disability and a significant source of healthcare resource utilization.