Interspinous and spinolaminar synthetic vertebropexy of the lumbar spine

PURPOSE: To develop and test synthetic vertebral stabilization techniques ("vertebropexy") that can be used after decompression surgery and furthermore to compare them with a standard dorsal fusion procedure. METHODS: Twelve spinal segments (Th12/L1: 4, L2/3: 4, L4/5: 4) were tested in a stepwise surgical decompression and stabilization study. Stabilization was achieved with a FiberTape cerclage, which was pulled through the spinous process (interspinous technique) or through one spinous process and around both laminae (spinolaminar technique). The specimens were tested (1) in the native state, after (2) unilateral laminotomy, (3) interspinous vertebropexy and (4) spinolaminar vertebropexy. The segments were loaded in flexion-extension (FE), lateral shear (LS), lateral bending (LB), anterior shear (AS) and axial rotation (AR). RESULTS: Interspinous fixation significantly reduced ROM in FE by 66% (p = 0.003), in LB by 7% (p = 0.006) and in AR by 9% (p = 0.02). Shear movements (LS and AS) were also reduced, although not significantly: in LS reduction by 24% (p = 0.07), in AS reduction by 3% (p = 0.21). Spinolaminar fixation significantly reduced ROM in FE by 68% (p = 0.003), in LS by 28% (p = 0.01), in LB by 10% (p = 0.003) and AR by 8% (p = 0.003). AS was also reduced, although not significantly: reduction by 18% (p = 0.06). Overall, the techniques were largely comparable. The spinolaminar technique differed from interspinous fixation only in that it had a greater effect on shear motion. CONCLUSION: Synthetic vertebropexy is able to reduce lumbar segmental motion, especially in flexion-extension. The spinolaminar technique affects shear forces to a greater extent than the interspinous technique

Correlation of Postoperative Imaging With MRI and Clinical Outcome After Cartilage Repair of the Ankle: A Systematic Review and Meta-analysis

BACKGROUND Magnetic resonance imaging (MRI) is commonly used for evaluation of ankle cartilage repair, yet its association with clinical outcome is controversial. This study analyzes the correlation between MRI and clinical outcome after cartilage repair of the talus including bone marrow stimulation, cell-based techniques, as well as restoration with allo- or autografting. METHODS A systematic search was performed in MEDLINE, Embase, and Cochrane Collaboration. Articles were screened for correlation of MRI and clinical outcome. Guidelines of Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) were used. Chi-square test and regression analysis were performed to identify variables that determine correlation between clinical and radiologic outcome. RESULTS Of 2687 articles, a total of 43 studies (total 1212 cases) were included with a mean Coleman score of 57 (range, 33-70). Overall, 93% were case series, and 5% were retrospective and 2% prospective cohort studies. Associations between clinical outcome and ≥1 imaging variable were found in 21 studies (49%). Of 24 studies (56%) using the composite magnetic resonance observation of cartilage repair tissue (MOCART) score, 7 (29%) reported a correlation of the composite score with clinical outcome. Defect fill was associated with clinical outcome in 5 studies (12%), and 5 studies (50%) reported a correlation of T2 mapping and clinical outcome. Advanced age, shorter follow-up, and larger study size were associated with established correlation between clinical and radiographic outcome (P = .021, P = .028, and P = .033). CONCLUSION Interpreting MRI in prediction of clinical outcome in ankle cartilage repair remains challenging; however, it seems to hold some value in reflecting clinical outcome in patients with advanced age and/or at a shorter follow-up. Yet, further research is warranted to optimize postoperative MRI protocols and assessments allowing for a more comprehensive repair tissue evaluation, which eventually reflect clinical outcome in patients after cartilage repair of the ankle.Level of Evidence: Level III, systematic review and meta-analysis

Alpaca - Parksystem Administration Service mit Silverlight

Die Firma Compark bietet neben der Beratung und dem Verkauf von Parkanlagen auch die Instandhaltung dieser Anlagen über Jahrzehnte hinweg an. In der Vision wurden die Ziele für dieses Projekt definiert. Das primäre Ziel war das Programm gemäss den Wünschen unsers Projektpartners zu entwickeln und die Arbeitsabläufe zu optimieren. Zusammen mit dem Kunden und dem Betreuer wurden die Anforderungen festgelegt. Das Programm muss in der Lage sein, Parkanlagen mit den zugehörigen Kontaktpersonen zu verwalten, sowie Offerten und die daraus resultierenden Auftragsbestätigungen zu erstellen. Des Weiteren soll das Programm die Möglichkeit bieten Rapporte für Revisionen oder Instandstellungsarbeiten zu generieren. Zusätzlich muss die Anwendung in Silverlight 2.0 als Rich Internet Application realisiert werden und als Software-as-a-Service Lösung mehrere Betriebe mit ähnlichen Bedürfnissen bedienen können. Es wurde nach RUP mit UCD Elementen gearbeitet, d.h. die Analyse, sowie auch die Anforderungen und später das Design wurden bei jeder Iteration wieder unter die Lupe genommen und allenfalls angepasst. Der Projektpartner wurde während des gesamten Projekts konsequent in den Entwicklungsprozess mit einbezogen. Unter anderem wurde ein Papierprototyptest mit dem Projektpartner durchgeführt um sicherzustellen, dass unsere Benutzeroberfläche funktional und benutzerfreundlich ist. Zusätzlich wurden mehrmals Usability Tests durchgeführt, um laufend unsere Benutzeroberfläche zu prüfen. Im Technologiestudium wurden die zu verwendenden Technologien evaluiert. Dabei wurde unter anderem entschieden, dass für die Datenhaltung der MS SQL Server Express eingesetzt und zur Datenanbindung Linq-To- Sql verwendet werden. Als Reportingtechnologie haben wir uns für Crystal Reports entschieden. Während der Analyse haben wir im Wesentlichen die Problem Domain mittels eines Domainmodells umschrieben. Das Design beinhaltete einerseits die Ausarbeitung der Softwarearchitektur, sowie auch die Beschreibung dieser Architektur in einem Software Architecture Document. Das Programm wurde als Client/Server- Anwendung konzipiert, wobei dem Benutzer die Anwendung durch einen Webserver zur Verfügung gestellt wird. Bei den Tests wurde während der Entwicklung mit Unit Tests gearbeitet. Während der Entwicklungsphase wurden wiederholt Usability Tests mit dem Projektpartner durchgeführt. Kurz vor Ende der Entwicklungsphase wurde dann ein Systemtest durchgeführt. Ein Abnahmetest durch den Projektpartner fand aus zeitlichen Gründen leider nicht statt. Im Projektmanagement wurden ein Zeit- und Risikomanagement sowie ein Projekt- und Qualitätscontrolling definiert. So haben wir beispielsweise Silverlight und Crystal Reports als Risiken definiert und Massnahmen ergriffen, um diese Risiken zu minimieren

Anterior cervical osteotomy of diffuse idiopathic skeletal hyperostosis lesions with computer‐assisted navigation surgery: A case report

Key Clinical Message Diffuse idiopathic skeletal hyperostosis (DISH) involves spine ligament ossification. Computer‐assisted navigation (CAN) effectively aids complex surgeries, such as anterior cervical osteotomy, to alleviate progressive DISH‐related dysphagia. Abstract We describe a 68‐year‐old man with sudden onset dysphagia to both solids and liquids. Radiographic Imaging revealed DISH lesions from C2 down to the thoracic spine. The patient was successfully treated with CAN anterior osteotomy and resection of DISH lesions from C3–C6 and had complete symptom relief within 2 weeks post‐operatively

Investigation of perfusion impairment in degenerative cervical myelopathy beyond the site of cord compression

The aim of this study was to determine tissue-specific blood perfusion impairment of the cervical cord above the compression site in patients with degenerative cervical myelopathy (DCM) using intravoxel incoherent motion (IVIM) imaging. A quantitative MRI protocol, including structural and IVIM imaging, was conducted in healthy controls and patients. In patients, T2-weighted scans were acquired to quantify intramedullary signal changes, the maximal canal compromise, and the maximal cord compression. T2*-weighted MRI and IVIM were applied in all participants in the cervical cord (covering C1-C3 levels) to determine white matter (WM) and grey matter (GM) cross-sectional areas (as a marker of atrophy), and tissue-specific perfusion indices, respectively. IVIM imaging resulted in microvascular volume fraction ([Formula: see text]), blood velocity ([Formula: see text]), and blood flow ([Formula: see text]) indices. DCM patients additionally underwent a standard neurological clinical assessment. Regression analysis assessed associations between perfusion parameters, clinical outcome measures, and remote spinal cord atrophy. Twenty-nine DCM patients and 30 healthy controls were enrolled in the study. At the level of stenosis, 11 patients showed focal radiological evidence of cervical myelopathy. Above the stenosis level, cord atrophy was observed in the WM (- 9.3%; p = 0.005) and GM (- 6.3%; p = 0.008) in patients compared to healthy controls. Blood velocity (BV) and blood flow (BF) indices were decreased in the ventral horns of the GM (BV: - 20.1%, p = 0.0009; BF: - 28.2%, p = 0.0008), in the ventral funiculi (BV: - 18.2%, p = 0.01; BF: - 21.5%, p = 0.04) and lateral funiculi (BV: - 8.5%, p = 0.03; BF: - 16.5%, p = 0.03) of the WM, across C1-C3 levels. A decrease in microvascular volume fraction was associated with GM atrophy (R = 0.46, p = 0.02). This study demonstrates tissue-specific cervical perfusion impairment rostral to the compression site in DCM patients. IVIM indices are sensitive to remote perfusion changes in the cervical cord in DCM and may serve as neuroimaging biomarkers of hemodynamic impairment in future studies. The association between perfusion impairment and cervical cord atrophy indicates that changes in hemodynamics caused by compression may contribute to the neurodegenerative processes in DCM

MRI appearance of adjunct surgical material used in spine surgery

BACKGROUND CONTEXT Early postoperative MR images are frequently necessary after spine surgery. The appearance of commonly used adjunct hemostatic agents and dural sealants in MR images has not been systematically evaluated. PURPOSE The purpose of this experimental study was to systematically analyze and describe the characteristics of the most commonly applied hemostatic agents and dural sealants in spine surgery on early postoperative MR images. STUDY DESIGN Cadaver Study METHODS: Four commonly applied dural sealants (Duraseal, Bioglue, Tachosil, Tisseel) and five commonly used hemostatic agents (Surgiflo, Bonewax, , Spongostan, Gelfoam, Avitene) were investigated. The experimental setting involved a human cadaver where a standard left-sided laminotomy was performed on nine levels of the thoracolumbar spine, and the materials were separately applied and mixed with fresh blood or water for hemostatic and dural sealants, respectively. The cadaver model was scanned at a 3 Tesla MRI and the imaging findings for all materials were compared to the surrounding tissue and systematically reported. RESULTS All investigated dural sealants and hemostatic agents were distinguishable from the surrounding tissue on MR images with different appearances on the MR sequences. A detailed atlas for the identification of the materials in postoperative spine MRI was established. CONCLUSION Commonly used hemostatic agents and dural sealants can be successfully identified on early postoperative spine MRI. CLINICAL SIGNIFICANCE Knowledge about MRI appearances of commonly used adjunct surgical materials helps in interpretation of postoperative imaging and supports clinical decision making

Investigation of perfusion impairment in degenerative cervical myelopathy beyond the site of cord compression

Abstract The aim of this study was to determine tissue-specific blood perfusion impairment of the cervical cord above the compression site in patients with degenerative cervical myelopathy (DCM) using intravoxel incoherent motion (IVIM) imaging. A quantitative MRI protocol, including structural and IVIM imaging, was conducted in healthy controls and patients. In patients, T2-weighted scans were acquired to quantify intramedullary signal changes, the maximal canal compromise, and the maximal cord compression. T2*-weighted MRI and IVIM were applied in all participants in the cervical cord (covering C1–C3 levels) to determine white matter (WM) and grey matter (GM) cross-sectional areas (as a marker of atrophy), and tissue-specific perfusion indices, respectively. IVIM imaging resulted in microvascular volume fraction ( $$F$$ F ), blood velocity ( $$D^{*}$$ D ∗ ), and blood flow ( $$F \cdot D^{*}$$ F · D ∗ ) indices. DCM patients additionally underwent a standard neurological clinical assessment. Regression analysis assessed associations between perfusion parameters, clinical outcome measures, and remote spinal cord atrophy. Twenty-nine DCM patients and 30 healthy controls were enrolled in the study. At the level of stenosis, 11 patients showed focal radiological evidence of cervical myelopathy. Above the stenosis level, cord atrophy was observed in the WM (− 9.3%; p = 0.005) and GM (− 6.3%; p = 0.008) in patients compared to healthy controls. Blood velocity (BV) and blood flow (BF) indices were decreased in the ventral horns of the GM (BV: − 20.1%, p = 0.0009; BF: − 28.2%, p = 0.0008), in the ventral funiculi (BV: − 18.2%, p = 0.01; BF: − 21.5%, p = 0.04) and lateral funiculi (BV: − 8.5%, p = 0.03; BF: − 16.5%, p = 0.03) of the WM, across C1–C3 levels. A decrease in microvascular volume fraction was associated with GM atrophy (R = 0.46, p = 0.02). This study demonstrates tissue-specific cervical perfusion impairment rostral to the compression site in DCM patients. IVIM indices are sensitive to remote perfusion changes in the cervical cord in DCM and may serve as neuroimaging biomarkers of hemodynamic impairment in future studies. The association between perfusion impairment and cervical cord atrophy indicates that changes in hemodynamics caused by compression may contribute to the neurodegenerative processes in DCM