Prevention of implant-associated spinal infections: the GAID-protocol

ObjectiveThe purpose of this study is to investigate the efficacy of the GAID-Protocol, a bundle of intra- and postoperative infection prevention measures, to reduce implant-associated infections in patients undergoing posterior spinal fusion with instrumentation. These preventive measures are organized into a protocol that includes recommendations for four critical areas of implant protection (acronym GAID): Gloves, Antiseptics: sodium hypochlorite/hypochlorous acid (NaOCl/HOCl), Implants and Drainage-use in large wounds.MethodsWe performed a single-site retrospective review of cases undergoing posterior spinal fusion with instrumentation for primarily degenerative spinal diseases before and after implementation of the GAID-Protocol that was specifically designed to protect against implant-associated infections. The primary outcome was postoperative wound complications requiring surgical intervention, with a particular focus on infectious spondylitis/discitis.Results230 cases were included: 92 (Group A) before and 138 (Group B) after protocol implementation. Overall, wound complications requiring surgical intervention occurred in 7.6% patients in Group A and in 3.6% patients in Group B (p = 0.2297). Of these, infectious spondylitis/discitis was present in 5.4% in Group A and in none of Group B (p = 0.0096). The ratio of infectious spondylitis/discitis to other wound problems was 71% to 29% in Group A, while it was 0% to 100% in Group B (p = 0.0278). The mean time interval between the first revision surgery for wound complications and hospital discharge was significantly different, 38 days SD 20.3 in Group A and 14.4 days SD 8.6 in Group B (p = 0.0442).ConclusionsIn our study, adherence to the GAID-Protocol resulted in a shift from severe to significantly less severe and easier to treat wound complications. Adoption of the GAID-Protocol might contribute to the reduction of implant-associated infections

Comparison of posterior foraminotomy and anterior foraminotomy with fusion for treating spondylotic foraminal stenosis of the cervical spine: study protocol for a randomized controlled trial (ForaC)

Background: Cervical radiculopathy caused by spondylotic foraminal stenosis may require surgical treatment. Surgical options include anterior cervical foraminotomy and fusion or posterior cervical foraminotomy. Controversy remains regarding the preferable surgical approach. Pertinent clinical evidence is limited to low-quality observational reports. Therefore, treatment decisions are predominantly based on the individual surgeon’s preference and skill. The study objective is to evaluate the efficacy and safety of posterior foraminotomy in comparison to anterior foraminotomy with fusion for the treatment of spondylotic foraminal stenosis. Methods/design: This is a multicenter randomized, controlled, parallel group superiority trial. A total of 88 adult patients are allocated in a ratio of 1:1. Sample size and power calculations were performed to detect the minimal clinically important difference of 14 points, with an expected standard deviation of 20 in the primary outcome parameter, Neck Disability Index, with a power of 80%, based on an assumed maximal dropout rate of 20%. Secondary outcome parameters include the Core Outcome Measures Index, which investigates pain, back-specific function, work disability, social disability and patient satisfaction. Changes in physical and mental health are evaluated using the Short Form-12 (SF-12) questionnaire. Moreover, radiological and health economic outcomes are evaluated. Follow-up is performed 3, 6, 12, 24, 36, 48 and 60 months after surgery. Major inclusion criteria are cervical spondylotic foraminal stenosis causing radiculopathy of C5, C6 or C7 and requiring decompression of one or two neuroforaminae. Study data generation (study sites) and data storage, processing and statistical analysis (Department of Medical Statistics, Informatics and Health Economics) are clearly separated. Data will be analyzed according to the intention-to-treat principle. Discussion: The results of the ForaC study will provide surgical treatment recommendations for spondylotic foraminal stenosis and will contribute to the understanding of its short- and long-term clinical and radiological postoperative course. This will hopefully translate into improvements in surgical treatment and thus, clinical practice for spondylotic foraminal stenosis. Trial registration Current Controlled Trials: ISRCTN8257806

Effects of initial boost with TGF-beta 1 and grade of intervertebral disc degeneration on 3D culture of human annulus fibrosus cells

Background: Three-dimensional (3D) culture in porous biomaterials as well as stimulation with growth factors are known to be supportive for intervertebral disc cell differentiation and tissue formation. Unless sophisticated releasing systems are used, however, effective concentrations of growth factors are maintained only for a very limited amount of time in in vivo applications. Therefore, we investigated, if an initial boost with transforming growth factor-beta 1 (TGF-beta 1) is capable to induce a lasting effect of superior cartilaginous differentiation in slightly and severely degenerated human annulus fibrosus (AF) cells. Methods: Human AF tissue was harvested during surgical treatment of six adult patients with lumbar spinal diseases. Grading of disc degeneration was performed with magnet resonance imaging. AF cells were isolated and expanded in monolayer culture and rearranged three-dimensionally in a porous biomaterial consisting of stepwise absorbable poly-glycolic acid and poly-(lactic-co-glycolic) acid and a supportive fine net of non-absorbable polyvinylidene fluoride. An initial boost of TGF-beta 1 or TGF-beta 1 and hyaluronan was applied and compared with controls. Matrix formation was assessed at days 7 and 21 by (1) histological staining of the typical extracellular matrix molecules proteoglycan and type I and type II collagens and by (2) real-time gene expression analysis of aggrecan, decorin, biglycan, type I, II, III, and X collagens as well as of catabolic matrix metalloproteinases MMP-2 and MMP-13. Results: An initial boost with TGF-beta 1 or TGF-beta 1 and hyaluronan did not enhance the expression of characteristic AF matrix molecules in our 3D culture system. AF cells showed high viability in the progressively degrading biomaterial. Stratification by grade of intervertebral disc degeneration showed that AF cells from both, slightly degenerated, or severely degenerated tissue are capable of significant up-regulations of characteristic matrix molecules in 3D culture. AF cells from severely degenerated tissue, however, displayed significantly lower up-regulations in some matrix molecules such as aggrecan. Conclusions: We failed to show a supportive effect of an initial boost with TGF-beta 1 in our 3D culture system. This underlines the need for further investigations on growth factor releasing systems

Potential of mesenchymal stem cells for chondrogenic differentiation in high- density-3D-cultures and in bioresorbable polymer fleece

Titelblatt und Inhaltsverzeichnis Einleitung Material und Methoden Ergebnisse Diskussion LiteraturverzeichnisMesenchymale Stammzellen (MSC) haben das Potential sich zu mesenchymalen Geweben zu differenzieren. Sie bieten sich daher als interessante Zellquelle für Ansätze des Tissue engineerings im Knorpelbereich an. Unser Ziel war es, die Effekte von TGF-ß1, Hyaluronsäure (HA) und Synovialflüssigkeit (SF) auf die chondrogene Differenzierung equiner MSC in hochdichten 3D-Kulturen als auch im bioresorbierbaren Polymer-Vlies zu studieren. Dafür wurde Knochenmark aus der Tibia von zwei 18 Monate alten Pferden gewonnen (Haflinger). Die MSC wurden mittels Zentrifugation über einen Percolldichtegradienten isoliert. Für die Chondrogenese in hochdichten 3-D-Kulturen wurden MSC zu Pellets zentrifugiert und in einem Medium kultiviert welches 10 ng/ml TGFß-1 oder 0,1 mg/ml HA (Hylartil®, Ostenil®) oder entweder 5%, 10% oder 50% autologe SF als Chondrogenese induzierenden Faktor enthielt. Im bioresorbierbaren Polymer- Vlies wurden entweder 10ng/ml TGF-ß1 oder 5% autologe SF als Chondrogenese induzierender Faktor genutzt. Chondrogene Differenzierung wurde über die Expression von Kollagen Typ-II und Proteoglycan nachgewiesen. In hochdichten 3D-Kulturen zeigten mit TGF-ß1 induzierte MSC die höchste Proteoglycan- Expression. Die Kombination von TGF-ß1 mit HA zeigte keinen synergistischen Effekt. Kulturen, die nur mit SF (unabhängig von der Konzentration) oder nur mit HA stimuliert wurden, zeigten eine deutliche, aber niedrigere Proteoglycan-Expression als die mit TGF-ß1 stimulierten Kulturen. Die Expression von Kollagen Typ II war in allen stimulierten Kulturen vergleichbar hoch. Im bioresorbierbaren Vlies zeigten MSC sowohl unter TGF-ß1 als auch unter autologer SF die Fähigkeit, extrazelluläre Matrix zu bilden, die reich an Proteoglycanen war und zu einem festen, knorpelartigen Vlies-Zell-Integrat führte. Mit autologer SF induzierte MSC zeigten dabei eine homogenere Verteilung von Zellen und extrazellulärer Matrix im Vlies als bei TGF-ß1 induzierten MSC, wo sich die Zellen und die extrazelluäre Matrix mehr an der Oberfläche des Vlieses fanden. Zusammengefasst lässt sich sagen, dass HA und SF Chondrogenese bei equinen MSC induzieren können. Dies ermutigt zu Anwendungen des Tissue engineering mit MSC bei chondralen Defekten, da die natürliche Umgebung im Gelenk der chondrogenen Differenzierung förderlich ist.Mesenchymal stem cells (MSC) have the potential to differentiate into distinct mesenchymal tissues including cartilage, which suggests these cells as an attractive cell source for cartilage tissue engineering approaches. Our objective was to study the effects of TGF-ß1, hyaluronic acid (HA) and synovial fluid (SF) on chondrogenic differentiation of equine MSC in high- density-3D-cultures as well as in bioresorbable polymer fleece. For that objective, bone marrow was aspirated from the tibia of two 18-month-old horses (Haflinger) and MSC were isolated using percoll-density centrifugation. To promote chondrogenesis in high-density-3D-cultures, MSC were centrifuged to form a micromass and were cultured in a medium containing 10 ng/ml TGF-ß1 or 0.1 mg/ml HA (Hylartil®, Ostenil®), or either 5%, 10% or 50% autologous SF, as the chondrogenesis inducing factor. In the bioresorbable polymer fleece either 10 ng/ml TGF-ß1 or 5% autologous SF were used as the chondrogenesis inducing factor. Differentiation along the chondrogenic lineage was documented by type II collagen and proteoglycan expression. In high-density-3D-cultures, MSC induced by TGF-ß1 alone showed the highest proteoglycan expression. Combining TGF-ß1 with HA could not increase the proteoglycan expression. Cultures stimulated by autologous SF (independent of concentration) or HA demonstrated a pronounced, but lower proteoglycan expression than cultures stimulated by TGF-ß1. The expression of cartilage-specific type II collagen was high and nearly the same in all stimulated cultures. In the bioresorbable polymer fleece, MSC induced either with TGF-ß1 or autologous SF showed the ability to produce extracellular matrix, rich in proteoglycans, resulting in a stiff, cartilage-like fleece-cell integrate. MSC induced with autologous SF showed a more homogeneous distribution of cells and extracellular matrix within the fleece than when induced with TGF-ß1, where cells and extracellular matrix were found more on the surface area of the fleece. In summary, HA and autologous SF induce chondrogenesis of equine MSC, which strongly suggests tissue engineering applications of MSC in chondral defects, as the natural environment in the joint is favorable for chondrogenic differentiation

Routine postoperative imaging early after lumbar decompression surgery: a prospective evaluation

Este estudo teve como objetivos analisar o protagonismo exercido pelos enfermeiros no Colegiado de Gestão Regional - COGERE a partir de sua formação acadêmica e compreender as tecnologias utilizadas por eles no seu processo de trabalho. Trata-se de estudo de caso com doze gestores do COGERE. Os dados foram coletados através das entrevistas e analisados mediante análise temática. A formação do enfermeiro se embasa no modelo biomédico, cujo núcleo de conhecimento mobiliza tecnologias duras e leve-duras, porém insuficiente para tecnologias leves. A atuação dos enfermeiros no campo da gestão em saúde requer maior constituição da noção de corresponsabilidade entre o aparelho formador e serviços de saúde, com implicação recíproca entre ensino, gestão, atenção e participação social.This study aimed to analyze the nurses’ role in a Regional Management Board - COGERE from their academic formation and understand the technologies used by them in their work process. It is a case study with twelve administrators from COGERE. Data were collected through interviews and analyzed using thematic analysis. The nursing academic formation was grounded in the biomedical model, which mobilizes hard and light-hard technologies, but not enough to hard technologies. The role of nurses in the field of health management requires a greater incorporation of the concept of co-responsibility between the educational system and health services, with a reciprocal implication among teaching, management, attention, and social participation.Este estudio tuvo como objetivo analizar el papel desempeñado por enfermeros en un Consejo de Administración Regional – COGERE a partir de su formación académica y comprender las tecnologías utilizadas por ellos en su proceso de trabajo. Se realizó un estudio de caso con 12 miembros del COGERE. Los datos fueron recogidos através de entrevistas y analizados mediante análisis temático. La formación de enfermería se basa en el modelo biomédico, que moviliza el conocimiento básico de las tecnologías duras y blandas-duras, pero insuficiente a las tecnología blandas. El papel de los enfermeros en el ámbito de la gestión en salud requiere una mayor incorporación del concepto de corresponsabilidad entre el aparato educativo y los servicios de salud, con la implicación mutua de la enseñanza, gestión, atención y participación social

Regenerative and Immunogenic Characteristics of Cultured Nucleus Pulposus Cells from Human Cervical Intervertebral Discs

<div><p>Cell-based regenerative approaches have been suggested as primary or adjuvant procedures for the treatment of degenerated intervertebral disc (IVD) diseases. Our aim was to evaluate the regenerative and immunogenic properties of mildly and severely degenerated cervical nucleus pulposus (NP) cells with regard to cell isolation, proliferation and differentiation, as well as to cell surface markers and co-cultures with autologous or allogeneic peripheral blood mononuclear cells (PBMC) including changes in their immunogenic properties after 3-dimensional (3D)-culture. Tissue from the NP compartment of 10 patients with mild or severe grades of IVD degeneration was collected. Cells were isolated, expanded with and without basic fibroblast growth factor and cultured in 3D fibrin/poly (lactic-co-glycolic) acid transplants for 21 days. Real-time reverse-transcription polymerase chain reaction (RT-PCR) showed the expression of characteristic NP markers <i>ACAN</i>, <i>COL1A1</i> and <i>COL2A1</i> in 2D- and 3D-culture with degeneration- and culture-dependent differences. In a 5,6-carboxyfluorescein diacetate N-succinimidyl ester-based proliferation assay, NP cells in monolayer, regardless of their grade of degeneration, did not provoke a significant proliferation response in T cells, natural killer (NK) cells or B cells, not only with donor PBMC, but also with allogeneic PBMC. In conjunction with low inflammatory cytokine expression, analyzed by Cytometric Bead Array and fluorescence-activated cell sorting (FACS), a low immunogenicity can be assumed, facilitating possible therapeutic approaches. In 3D-culture, however, we found elevated immune cell proliferation levels, and there was a general trend to higher responses for NP cells from severely degenerated IVD tissue. This emphasizes the importance of considering the specific immunological alterations when including biomaterials in a therapeutic concept. The overall expression of Fas receptor, found on cultured NP cells, could have disadvantageous implications on their potential therapeutic applications because they could be the targets of cytotoxic T-cell activity acting by Fas ligand-induced apoptosis.</p></div

Surface marker expression of NP cells.

<p>NP cells were labeled with specific antibodies and analyzed by FACS. The percentage of marker positive cells (mean ± SEM; n = 5) is shown as a comparison between NP cells from patients with mild (white bars) or severe (black bars) degeneration; * p≤0.05.</p

MRT scoring of IVD degeneration and NP cell cultivation.

<p>Examples of MRT-scoring for different IVD degeneration grades are given for mild disc degeneration (<b>A</b>) and severe disc degeneration (<b>B</b>). Cells from all samples were able to proliferate with or without basicFGF, and showed a fibroblast-like morphology (<b>C</b>) in primary cell culture. The cells developed a slightly larger, more stretched phenotype (<b>D</b>) during cultivation (passage 2); (<b>C</b> and <b>D</b> 100x, scale bars: 200μm).</p

Overall scoring of the Safranin O staining and the immunochemical collagen type II staining.

<p>stained = +, weakly stained = (+), unstained = -</p><p>Overall scoring of the Safranin O staining and the immunochemical collagen type II staining.</p