F C Oner

University Medical Center Utrecht, Utrecht, Utrecht, Netherlands

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Publications (177)456.74 Total impact


  • No preview · Article · Dec 2015 · Spine
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    ABSTRACT: Background. Stable spinal metastases are effectively treated with radiotherapy,whereas unstable spinalmetastases often need surgical fixation followed by radiotherapy for local control. The Spinal Instability Neoplastic Score (SINS) was developed as a tool to assess spinal neoplastic related instability with the goal of helping to guide referrals among oncology specialists. We compare the average degree of spinal instability between patients with spinal metastases referred for surgeryor for radiotherapy and evaluatewhether this difference changed after introduction of the SINS in clinical practice. Methods. All patients with spinal metastases treated with palliative surgery or radiotherapy in the period 2009–2013 were identified in two spine centers. For all patients, the SINS was scored on pretreatment imaging. The SINS before and after introduction of the SINS in 2011 were compared within the surgical and radiotherapy group. Furthermore, the overall SINS was compared between the two groups. Results. The overall SINS was significantly higher in the surgical group, with a mean SINS of 10.7 (median 11) versus 7.2 (median 8) for the radiotherapy group. The mean SINS decreased significantly for both groups after introduction of the SINS in clinical practice from 11.2 to 10.3 in the surgical group and from 8.4 to 7.2 in the radiotherapy group. Conclusion. The SINS differed significantly between patients treated with surgery or radiotherapy.The introduction of SINS led to a decrease in SINS score for both groups, suggesting that using SINS in metastatic spinal disease increases awareness for instability and may subsequently result in earlier referrals for surgical intervention.
    No preview · Article · Dec 2015 · The Oncologist
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    ABSTRACT: Vascularisation is crucial for the induction of bone formation. Here, we investigated the application of two subtypes of peripheral blood derived endothelial progenitor cells (EPCs) to stimulate vessel formation in ectopic bone constructs. Early- and late outgrowth EPCs (E-EPC and L-EPC, respectively) were characterized for their ability to form network structures in vitro and perfused vessels subcutaneously in mice. Only L-EPCs showed the formation of fully connected networks on Matrigel 2D angiogenesis assays. The presence of MSCs inhibited network formation in 2D assays, but stimulated network formation in 3D plugs. In vivo studies revealed that at 2 weeks, the highest incidence of formed perfused vessels was reached by implanted E-EPC/MSC constructs and this could be attributed to the presence of E-EPCs. L-EPCs displayed a significantly lower frequency of blood vessel formation than E-EPCs and this was accompanied by a lowering of total luminal area densities. Nevertheless, combined E-EPC/L-EPC application somewhat increased the percentage incidence of perfused vessels. After 6 weeks, differences in vascularisation were still obvious as all three EPC-based constructs contained higher numbers of perfused vessels than constructs containing MSCs alone. Bone was formed in all constructs at an incidence that coincided with high density of perfused vessels after 2 weeks. Altogether, our findings suggest the differential establishment of vascular networks by E-EPCs and L-EPCs and suggest the importance of early vasculogenesis in ectopic bone formation.
    No preview · Article · Dec 2015 · Tissue Engineering Part A
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    ABSTRACT: Background Spondylodiscitis is a spinal infection affecting primarily the intervertebral disk and the adjacent vertebral bodies. Currently many aspects of the treatment of pyogenic spondylodiscitis are still a matter of debate. Purpose The aim of this study was to review the currently available literature systematically to determine the outcome of patients with pyogenic spondylodiscitis for conservative and surgical treatment strategies. Methods A systematic electronic search of MEDLINE, EMBASE, Cochrane Collaboration, and Web of Science regarding the treatment of pyogenic spondylodiscitis was performed. Included articles were assessed on risk of bias according the Cochrane Handbook for Systematic Reviews of Interventions, and the quality of evidence and strength of recommendation was evaluated according the GRADE approach. Results 25 studies were included. Five studies had a high or moderate quality of evidence. One RCT suggest that 6 weeks of antibiotic treatment of pyogenic spondylodiscitis results in a similar outcome when compared to longer treatment duration. However, microorganism-specific studies suggest that at least 8 weeks of treatment is required for S. aureus and 8 weeks of Daptomycin for MRSA. The articles that described the outcome of surgical treatment strategies show that a large variety of surgical techniques can successfully treat spondylodiscitis. No additional long-term beneficial effect of surgical treatment could be shown in the studies comparing surgical versus antibiotic only treatment. Conclusion There is a strong level of recommendation for 6 weeks of antibiotic treatment in pyogenic spondylodiscitis although this has only been shown by one recent RCT. If surgical treatment is indicated, it has been suggested by two prospective studies with strong level of recommendation that an isolated anterior approach could result in a better clinical outcome.
    No preview · Article · Nov 2015 · European Spine Journal
  • F. R. J. Groen · D. Delawi · M. C. Kruyt · F. C. Oner
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    ABSTRACT: Purpose This study aimed at discussing the relevance of the type B3 fracture of the new AOSpine classification. Methods Hyperextension fractures of the spine are rare in the general population, but common in the ankylotic spine. We present a case of a severe spinal fracture with concomitant esophageal rupture, which was diagnosed early and could be treated during the initial trauma care. Results The spinal column was stabilized using a percutaneous technique after which the perforated esophagus was sutured through a thoracotomy. The spinal injury was classified a type B3 fracture using the new AOSpine classification. Conclusion The B3 typification raised a lot of discussion during the development of the new classification system and may be controversial. This case, however, nicely illustrates the relevance of an intact posterior hinge as compared to C-type injuries where complete dissociation is present with inherent spinal cord damage.
    No preview · Article · Nov 2015 · European Spine Journal
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    Full-text · Article · Sep 2015 · Global Spine Journal
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    ABSTRACT: Study Design Literature review. Objective The aim of this review is to highlight challenges in the development of a comprehensive surgical algorithm to accompany the AOSpine Thoracolumbar Spine Injury Classification System. Methods A narrative review of the relevant spine trauma literature was undertaken with input from the multidisciplinary AOSpine International Trauma Knowledge Forum. Results The transitional areas of the spine, in particular the cervicothoracic junction, pose unique challenges. The upper thoracic vertebrae have a transitional anatomy with elements similar to the subaxial cervical spine. When treating these fractures, the surgeon must be aware of the instability due to the junctional location of these fractures. Additionally, although the narrow spinal canal makes neurologic injuries common, the small pedicles and the inability to perform an anterior exposure make decompression surgery challenging. Similarly, low lumbar fractures and fractures at the lumbosacral junction cannot always be treated in the same manner as fractures in the more cephalad thoracolumbar spine. Although the unique biomechanical environment of the low lumbar spine makes a progressive kyphotic deformity less likely because of the substantial lordosis normally present in the low lumbar spine, even a fracture leading to a neutral alignment may dramatically alter the patient's sagittal balance. Conclusion Although the new AOSpine Thoracolumbar Spine Injury Classification System was designed to be a comprehensive thoracolumbar classification, fractures at the cervicothoracic junction and the lumbosacral junction have properties unique to these junctional locations. The specific characteristics of injuries in these regions may alter the most appropriate treatment, and so surgeons must use clinical judgment to determine the optimal treatment of these complex fractures.
    Full-text · Article · Aug 2015 · Global Spine Journal
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    ABSTRACT: With recent advances in oncologic treatments, there has been an increase in patient survival rates and concurrently an increase in the number of incidence of symptomatic spinal metastases. Elderly patients are a substantial part of the oncology population, and therefore their treatments still need to be questioned as well as their possible impact on healthcare resources. We studied whether age has a significant influence on quality of life and survival in surgical interventions for spinal metastases. We used the data from a multicentre prospective study by the Global Spine Tumor Study Group (GSTSG) of 1,266 patients who were admitted for surgical treatments of symptomatic spinal metastases at 22 spinal centers from different countries, followed for 2 years after surgery. 1,266 patients were recruited between March 2001 and October 2014. Patient demographics were collected along with outcome measures including EQ-5D quality of life, neurological functions, complications and survival rates. We realized a multicentre prospective study of 1,266 patients admitted for surgical treatment of symptomatic spinal metastases. They were divided and studied into 3 different age groups, <70, 70-80 and > 80 years. Patients over 80 were more likely to undergo emergency surgery and palliative procedures compared to younger patients, despite a lack of statistical difference in American Society of Anesthesiology (ASA) score, Frankel neurological score or Karnofsky functional score at presentation. Post-operative complications were more common in the oldest age group (33.3% in the over 80s, 23.9% in the 70-80, and 17.9% for patients under 70 years old, p=0.004). EQ-5D improved in all groups, but survival expectancy was significantly longer in patients younger than 70 years old (p=0.02). Furthermore, neurological recovery after surgery was lower in patients older than 80 years. Surgeons should not be biased against operating elderly patients. Although survival rates and neurological improvements are lower than for younger patients, this is compounded by the fact that elderly patients undergo more emergency and palliative procedures, despite good ASA scores and functional status. Age in itself should not be a determinant of whether to operate or not, and operations should not be avoided in the elderly when indicated. Copyright © 2015 Elsevier Inc. All rights reserved.
    Full-text · Article · Jul 2015 · The spine journal: official journal of the North American Spine Society
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    ABSTRACT: Bone morphogenetic protein-2 (BMP-2) gene delivery has shown to induce bone formation in vivo in cell-based tissue engineering. In addition, the chemoattractant stromal cell-derived factor-1α (SDF-1α, also known as CXCL12) is known to recruit multipotent stromal cells towards its release site where it enhances vascularisation and possibly contributes to osteogenic differentiation. To investigate potential cooperative behaviour for bone formation, we investigated combined release of BMP-2 and SDF-1α on ectopic bone formation in mice. Multipotent stromal cell-seeded and cell-free constructs with BMP-2 plasmid DNA and /or SDF-1α loaded onto gelatin microparticles, were implanted subcutaneously in mice for a period of 6 weeks. Histological analysis and histomorphometry revealed that the onset of bone formation and the formed bone volume were both enhanced by the combination of BMP-2 and SDF-1α compared to controls in cell-seeded constructs. Samples without seeded multipotent stromal cells failed to induce any bone formation. We conclude that the addition of stromal cell-derived factor-1α to a cell-seeded alginate based bone morphogenetic protein-2 plasmid DNA construct has an additive effect on bone formation and can be considered a promising combination for bone regeneration.
    No preview · Article · Jul 2015 · European cells & materials
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    ABSTRACT: Surgery for symptomatic spinal metastases aims to improve quality of life, pain, function, and stability. Complications in the postoperative period are not uncommon; therefore, it is important to select appropriate patients who are likely to benefit the greatest from surgery. Previous studies have focused on predicting survival rather than quality of life after surgery. To determine preoperative patient characteristics that predict postoperative quality of life and survival in patients who undergo surgery for spinal metastases. In a prospective cohort study of 922 patients with spinal metastases who underwent surgery, we performed preoperative and postoperative assessment of EuroQol EQ-5D quality of life, visual analog score for pain, Karnofsky physical functioning score, complication rates, and survival. The primary tumor type, number of spinal metastases, and presence of visceral metastases were independent predictors of survival. Predictors of quality of life after surgery included preoperative EQ-5D (P = .002), Frankel score (P < .001), and Karnofsky Performance Status (P < .001). Data from the largest prospective surgical series of patients with symptomatic spinal metastases revealed that tumor type, the number of spinal metastases, and the presence of visceral metastases are the most useful predictors of survival and that quality of life is best predicted by preoperative Karnofsky, Frankel, and EQ-5D scores. The Karnofsky score predicts quality of life and survival and is easy to determine at the bedside, unlike the EQ-5D index. Karnofsky score, tumor type, and spinal and visceral metastases should be considered the 4 most important prognostic variables that influence patient management. ASA, American Society of AnesthesiologistsCI, confidence intervalQoL, quality of life.
    No preview · Article · Jul 2015 · Neurosurgery
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    ABSTRACT: Several inflammatory processes underlie excessive bone formation, including chronic inflammation of the spine, acute infections, or periarticular ossifications after trauma. This suggests that local factors in these conditions have osteogenic properties. Mesenchymal stem cells (MSCs) and their differentiated progeny contribute to bone healing by synthesizing extracellular matrix and inducing mineralization. Due to the variation in experimental designs used in vitro, there is controversy about the osteogenic potential of proinflammatory factors on MSCs. Our goal was to determine the specific conditions allowing the pro-osteogenic effects of distinct inflammatory stimuli. Human bone marrow MSCs were exposed to tumor necrosis factor alpha (TNF-α) and lipopolysaccharide (LPS). Cells were cultured in growth medium or osteogenic differentiation medium. Alternatively, bone morphogenetic protein 2 (BMP-2) was used as osteogenic supplement to simulate the conditions in vivo. Alkaline phosphatase activity and calcium deposition were indicators of osteogenicity. To elucidate lineage commitment-dependent effects, MSCs were pre-differentiated prior treatment. Our results show that TNF-α and LPS do not affect the expression of osteogenic markers by MSCs in the absence of an osteogenic supplement. In osteogenic differentiation medium or together with BMP-2 however, these mediators highly stimulated their alkaline phosphatase activity and subsequent matrix mineralization. In pre-osteoblasts, matrix mineralization was significantly increased by these mediators, but irrespective of the culture conditions. Our study shows that inflammatory factors potently enhance the osteogenic capacity of MSCs. These properties may be harnessed in bone regenerative strategies. Importantly, the commitment of MSCs to the osteogenic lineage greatly enhances their responsiveness to inflammatory signals.
    Full-text · Article · Jul 2015 · PLoS ONE
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    ABSTRACT: International validation studyObjective. To investigate the influence of the spine surgeons' level of experience on the intraobserver reliability of the novel AOSpine Thoracolumbar Spine Injury Classification system, and the appropriate classification according to this system. Wide variability has been demonstrated for intraobserver reliability of the AOSpine classification system. The spine surgeons' level of experience may play a crucial role in the appropriate classification of thoracolumbar fractures, and the degree of reproducibility of the same observer on separate occasions. However, this has not been previously investigated. After a training on the classification system, high quality CT images together with clinical data from 25 patients with thoracolumbar fractures were independently assessed by 100 spine surgeons from across the world on two different occasions, one month apart from each other. The spine surgeons were allocated to a subgroup, according to their years of experience. Intraobserver reliability was calculated for each individual surgeon and for each subgroup, using the Kappa statistics (κ). Descriptive statistics was used to describe any differences between the subgroups. Analysis of any misclassifications was performed by calculating sensitivity and specificity estimates. Almost all surgeons demonstrated at least moderate intraobserver reliability. All surgeon subgroups demonstrated substantial reliability (κ = 0.67-0.69) for fracture subtype grading, and almost all subgroups demonstrated excellent reliability (κ = 0.79-0.83) for fracture morphology type regardless of subtype identified. In general, the fractures were most frequently misclassified by the most experienced surgeons. No major differences were observed among the subgroups when comparing the sensitivity and specificity rates. This international study demonstrated that the spine surgeons' level of experience does not substantially influence the classification and intraobserver reliability of the recently described AOSpine Thoracolumbar Spine Injury Classification System.
    Full-text · Article · Jul 2015 · Spine
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    ABSTRACT: Conflicts of interest arising from ties between pharmaceutical industry and physicians are common and may bias research. The extent to which these ties exist among editorial board members of medical journals is not known. This study aims to determine the prevalence and financial magnitude of potential conflicts of interest among editorial board members of five leading spine journals. The editorial boards of: The Spine Journal; Spine; European Spine Journal; Journal of Neurosurgery: Spine; and Journal of Spinal Disorders & Techniques were extracted on January 2013 from the journals' websites. Disclosure statements were retrieved from the 2013 disclosure index of the North American Spine Society; the program of the 20th International Meeting on Advanced Spine Techniques; the program of the 48th Annual Meeting of the Scoliosis Research Society; the program of the AOSpine global spine congress; the presentations of the 2013 Annual Eurospine meeting; and the disclosure index of the American Academy of Orthopaedic Surgeons. Names of the editorial board members were compared with the individuals who completed a disclosure for one of these indexes. Disclosures were extracted when full names matched. Two hundred and ten (29%) of the 716 identified editorial board members reported a potential conflict of interest and 154 (22%) reported nothing to disclose. The remaining 352 (49%) editorial board members had no disclosure statement listed for one of the indexes. Eighty-nine (42%) of the 210 editorial board members with a potential conflict of interest reported a financial relationship of more than $10,000 during the prior year. This finding confirms that potential conflicts of interest exist in editorial boards which might influence the peer review process and can result in bias. Academia and medical journals in particular should be aware of this and strive to improve transparency of the review process. We emphasize recommendations that contribute to achieving this goal.
    Full-text · Article · Jun 2015 · PLoS ONE
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    ABSTRACT: The goal of the current study is to establish a surgical algorithm to accompany the AOSpine thoracolumbar spine injury classification system. A survey was sent to AOSpine members from the six AO regions of the world, and surgeons were asked if a patient should undergo an initial trial of conservative management or if surgical management was warranted. The survey consisted of controversial injury patterns. Using the results of the survey, a surgical algorithm was developed. The AOSpine Trauma Knowledge forum defined that the injuries in which less than 30 % of surgeons would recommend surgical intervention should undergo a trial of non-operative care, and injuries in which 70 % of surgeons would recommend surgery should undergo surgical intervention. Using these thresholds, it was determined that injuries with a thoracolumbar AOSpine injury score (TL AOSIS) of three or less should undergo a trial of conservative treatment, and injuries with a TL AOSIS of more than five should undergo surgical intervention. Operative or non-operative treatment is acceptable for injuries with a TL AOSIS of four or five. The current algorithm uses a meaningful injury classification and worldwide surgeon input to determine the initial treatment recommendation for thoracolumbar injuries. This allows for a globally accepted surgical algorithm for the treatment of thoracolumbar trauma.
    Full-text · Article · May 2015 · European Spine Journal
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    ABSTRACT: Empirical cross-sectional multicenter study. To identify the most commonly experienced problems by patients with traumatic spinal column injuries, excluding patients with complete paralysis. There is no disease or condition-specific outcome instrument available that is designed or validated for patients with spine trauma, contributing to the present lack of consensus and ongoing controversies in the optimal treatment and evaluation of many types of spine injuries. Therefore, AOSpine Knowledge Forum Trauma started a project to develop such an instrument using the International Classification of Functioning, Disability and Health (ICF) as its basis. Patients with traumatic spinal column injuries, within 13 months after discharge from hospital were recruited from 9 trauma centers in 7 countries, representing 4 AOSpine International world regions. Health professionals collected the data using the general ICF Checklist. The responses were analyzed using frequency analysis. Possible differences between the world regions and also between the subgroups of potential modifiers were analyzed using descriptive statistics and Fisher exact test. In total, 187 patients were enrolled. A total of 38 (29.7%) ICF categories were identified as relevant for at least 20% of the patients. Categories experienced as a difficulty/impairment were most frequently related to activities and participation (n = 15), followed by body functions (n = 6), and body structures (n = 5). Furthermore, 12 environmental factors were considered to be a facilitator in at least 20% of the patients. Of 128 ICF categories of the general ICF Checklist, 38 ICF categories were identified as relevant. Loss of functioning and limitations in daily living seem to be more relevant for patients with traumatic spinal column injuries rather than pain during this time frame. This study creates an evidence base to define a core set of ICF categories for outcome measurement in adult spine trauma patients. 4.
    Full-text · Article · May 2015 · Spine
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    Full-text · Article · May 2015 · Spine
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    ABSTRACT: Retrospective cohort. Spinal injuries of the survivors of an airplane crash are described. On the basis of injury morphology and knowledge of the conditions of the accident, injury mechanisms are described and prevention measures are discussed. The most common causes of spinal fractures are a high energy fall (incidence 21.2%-39%) and motor vehicle accidents (21.7%-33.61%). Detailed reports solely on spinal injuries, as a result of an airplane crash, are scarce in literature. An analysis was performed on the spinal injuries of all 126 survivors of a commercial airplane (Boeing 737) crash near Amsterdam in 2009. Level of injury and fracture classification by morphology, independently performed by 4 specialists in spinal trauma, was documented. An analysis was done on the type of injuries and the suggested mechanism of injury by evaluating the crash characteristics analysis. Twenty-three (18.3%) of the survivors sustained a total of 27 spinal injuries. Four (17.1% of the patients with spinal injury) experienced a single cervical spine fracture. Eight (29.6%) injuries were at the thoracic spine and 15 (55.6%) at the lumbar spine level. More than half of the injuries included a burst component. A high number of spinal injuries was found after this airplane crash. The morphology of the injuries consisted of a high rate of burst-type fractures presumably caused by a mainly vertical trauma mechanism as shown by the accident analysis. 4.
    No preview · Article · Apr 2015 · Spine
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    ABSTRACT: Study Design. Survey of spine surgeons. Objective. To develop a validated regional and global injury severity scoring system for thoracolumbar trauma. Summary of Background Data. The AOSpine Thoracolumbar Spine Injury Classification System was recently published and combines elements of both the Magerl system and the Thoracolumbar Injury Classification System; however, the injury severity of each fracture has yet to be established. Methods. A survey was sent to 100 AOSpine members from all 6 AO regions of the world (North America, South America, Europe, Africa, Asia, and the Middle East). Each respondent was asked to numerically grade the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System including the morphology, neurological grade, and patient specific modifiers. A grade of zero was considered to be not severe at all, and a grade of 100 was the most severe injury possible. Results. Seventy-four AOSpine surgeons from all 6 AO regions of the world numerically graded the severity of each variable of the AOSpine Thoracolumbar Spine Injury Classification System to establish the injury severity score. The reported fracture severity increased significantly (P < 0.0001) as the subtypes of fracture type A and type B increased, and a significant difference (P < 0.0001) in severity was established for burst fractures with involvement of 2 versus 1 endplates. Finally, no regional or experiential difference in severity or classification was identified. Conclusion. Development of a globally applicable injury severity scoring system for thoracolumbar trauma is possible. This study demonstrates no regional or experiential difference in perceived severity or thoracolumbar spine trauma. The AOSpine Thoracolumbar Spine Injury Classification System provides a logical approach to assessing these injuries and enables rational strategies for treatment. Level of Evidence: 4
    Full-text · Article · Apr 2015 · Spine
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    ABSTRACT: Study Design Survey of spine surgeons. Objective To determine the reliability with which international spine surgeons identify a posterior ligamentous complex (PLC) injury in a patient with a compression-type vertebral body fracture (type A). Methods A survey was sent to all AOSpine members from the six AO regions of the world. The survey consisted of 10 cases of type A fractures (2 subtype A1, 2 subtype A2, 3 subtype A3, and 3 subtype A4 fractures) with appropriate imaging (plain radiographs, computed tomography, and/or magnetic resonance imaging), and the respondent was asked to identify fractures with a PLC disruption, as well as to indicate if the integrity of the PLC would affect their treatment recommendation. Results Five hundred twenty-nine spine surgeons from all six AO regions of the world completed the survey. The overall interobserver reliability in determining the integrity of the PLC was slight (kappa = 0.11). No substantial regional or experiential difference was identified in determining PLC integrity or its absence; however, a regional difference was identified (p < 0.001) in how PLC integrity influenced the treatment of type A fractures. Conclusion The results of this survey indicate that there is only slight international reliability in determining the integrity of the PLC in type A fractures. Although the biomechanical importance of the PLC is not in doubt, the inability to reliably determine the integrity of the PLC may limit the utility of the M1 modifier in the AOSpine Thoracolumbar Spine Injury Classification System.
    Full-text · Article · Mar 2015 · Global Spine Journal
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    ABSTRACT: Treatment and reconstruction of large bone defects, delayed unions and non-unions is challenging and has resulted in an ongoing search for novel tissue-engineered therapies. Bone morphogenetic protein-2 (BMP-2) gene therapy is a promising strategy to provide a sustained production of BMP-2 locally. Alginate polymer based non-viral gene therapy with BMP-2 plasmid DNA (pBMP-2) in constructs with multipotent mesenchymal stromal cells (MSCs) has resulted in prolonged gene expression and bone formation in vivo. To further translate this technology towards larger animal models, important issues remain to be investigated, such as the necessity of seeded cells as a target for gene therapy. For that purpose, a large animal-screening model in an orthotopic location, with fully separated chambers, was investigated. Four cylinder shaped implants were placed in the iliac crests of ten goats. Polycaprolactone tubes around each implant allowed bone ingrowth from the underlying bone and bone marrow and ensured separation of the experimental conditions. An empty tube showed low levels of spontaneous bone ingrowth and implantation of autologous bone indicated proper bone function with respect to remodeling and resorption. Control ceramic scaffolds were compared to scaffolds containing pBMP-2 either or not combined with seeded MSCs. Fluorochrome incorporation, evaluated at three, six and nine weeks and histomorphometry at twelve weeks after implantation revealed clear differences between the groups, with pBMP-2 combined with MSCs being most effective. BMP-2 protein was demonstrated in a variety of bone-residing cells through immunohistochemistry. Further analysis indicated that multinucleated giant cells might have an important role in transgene expression. Taken together, this work introduces a large animal model for studying bone formation at multiple sites simultaneously in an orthotopic location. The model appeared robust, showed no neighboring effects and demonstrated effectivity of combined cell-and gene therapy.
    No preview · Article · Feb 2015 · Tissue Engineering Part A

Publication Stats

4k Citations
456.74 Total Impact Points

Institutions

  • 1995-2015
    • University Medical Center Utrecht
      • • Orthopedic Surgery
      • • Department of Orthopedics
      Utrecht, Utrecht, Netherlands
  • 1995-2014
    • Utrecht University
      • • Division of Orthopaedics
      • • Department of Clinical Sciences of Companion Animals
      Utrecht, Utrecht, Netherlands
  • 2007
    • University of British Columbia - Vancouver
      • Department of Orthopaedics
      Vancouver, British Columbia, Canada
  • 2005-2006
    • University of Toronto
      • Division of Neurosurgery
      Toronto, Ontario, Canada
    • Thomas Jefferson University
      • Department of Orthopaedic Surgery
      Philadelphia, PA, United States
    • Radboud University Medical Centre (Radboudumc)
      Nymegen, Gelderland, Netherlands