46 results on '"Rene Schmid"'
Search Results
2. Pedicle screw augmentation in posterior constructs of the thoracolumbar spine: How many pedicle screws should be augmented?
- Author
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Anna Spicher, Richard Andreas Lindtner, Michael Josef Zegg, Rene Schmid, Romed Hoermann, and Werner Schmoelz
- Subjects
Biophysics ,Orthopedics and Sports Medicine - Published
- 2023
- Full Text
- View/download PDF
3. Ein spieltheoretischer Ansatz für das IT-Security-Risikomanagement - Ergebnisse des SERIMA-Projekts.
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Stefan Schauer, Benjamin Rainer, and Rene Schmid
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- 2012
- Full Text
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4. Cervical Disc and Ligamentous Injury in Hyperextension Trauma: MRI and Intraoperative Correlation
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Michael Zegg, Benjamin Henninger, Rene Schmid, Dietmar Krappinger, Anna Spicher, Christian Kremser, Verena Kaser, and Stefanie Ostermann
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Adult ,Male ,injury ,Hyperextension ,cervical spine ,030218 nuclear medicine & medical imaging ,Lesion ,03 medical and health sciences ,Anterior longitudinal ligament ,0302 clinical medicine ,Hematoma ,Multidetector Computed Tomography ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Intervertebral Disc ,Spinal Cord Injuries ,Original Research ,Aged ,Aged, 80 and over ,medicine.diagnostic_test ,business.industry ,Cervical Cord ,Magnetic resonance imaging ,Intervertebral disc ,Middle Aged ,Spinal cord ,medicine.disease ,Magnetic Resonance Imaging ,Sagittal plane ,medicine.anatomical_structure ,Clinical Investigative Study ,Female ,Neurology (clinical) ,medicine.symptom ,Nuclear medicine ,business ,030217 neurology & neurosurgery ,MRI - Abstract
BACKGROUND AND PURPOSE To identify and evaluate diagnostic magnetic resonance imaging (MRI) features in patients with suspicion of discoligamentous cervical injury after hyperextension trauma of the cervical spine. METHODS MR images with a standard protocol (1.5 T, including sagittal T2‐weighted images and short tau inversion recovery [STIR]) in 21 patients without any sign of fracture or instability on multidetector computed tomography of the cervical spine were assessed. Among other structures we evaluated the following: prevertebral hematoma, anterior longitudinal ligament (ALL), intervertebral disc, and spinal cord. Presence and the anatomic level of injury were identified and recorded. Results were then compared with intraoperative findings as a reference standard. Simple descriptive statistical analysis, agreement coefficients (given by calculating the percent agreement), and the determination of Gwet's AC1 coefficient were used to analyze our results. RESULTS The overall percent agreement between STIR and intraoperative findings was 90.9% (AC1 = .881) and for T2 69.7% (AC1 = .498). For the ALL, the overall agreement was 87.9% (AC1 = .808) and for the intervertebral disc 78.8% (AC1 = .673), in which STIR always showed a higher agreement. Prevertebral hematoma was found in 20 of 21 patients with the maximum thickness at the same anatomic level as the intraoperatively proven lesion in 12 of 18 patients (67%). Edema and/or hemorrhage of the spinal cord was shown in 16 of 21 being at the same anatomic level as the intraoperatively confirmed pathology in 16 of 16 patients (100%). CONCLUSIONS MRI is a reliable tool for the evaluation of discoligamentous injuries in the cervical spine, with ancillary features proven as helpful information.
- Published
- 2019
5. PLIF in thoracolumbar trauma: technique and radiological results
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Rene, Schmid, Dietmar, Krappinger, Peter, Seykora, Michael, Blauth, and Anton, Kathrein
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- 2010
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6. LOGGIC/FIREFLY-2: a phase 3, randomized trial of tovorafenib vs. chemotherapy in pediatric and young adult patients with newly diagnosed low-grade glioma harboring an activating RAF alteration
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Cornelis M. van Tilburg, Lindsay B. Kilburn, Sébastien Perreault, Rene Schmidt, Amedeo A. Azizi, Ofelia Cruz-Martínez, Michal Zápotocký, Katrin Scheinemann, Antoinette Y. N. Schouten-van Meeteren, Astrid Sehested, Enrico Opocher, Pablo Hernáiz Driever, Shivaram Avula, David S. Ziegler, David Capper, Arend Koch, Felix Sahm, Jiaheng Qiu, Li-Pen Tsao, Samuel C. Blackman, Peter Manley, Till Milde, Ruth Witt, David T. W. Jones, Darren Hargrave, and Olaf Witt
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Chemotherapy ,First-line ,Pediatric low-grade glioma ,pLGG ,Tovorafenib ,Child ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background Pediatric low-grade glioma (pLGG) is essentially a single pathway disease, with most tumors driven by genomic alterations affecting the mitogen-activated protein kinase/ERK (MAPK) pathway, predominantly KIAA1549::BRAF fusions and BRAF V600E mutations. This makes pLGG an ideal candidate for MAPK pathway-targeted treatments. The type I BRAF inhibitor, dabrafenib, in combination with the MEK inhibitor, trametinib, has been approved by the United States Food and Drug Administration for the systemic treatment of BRAF V600E-mutated pLGG. However, this combination is not approved for the treatment of patients with tumors harboring BRAF fusions as type I RAF inhibitors are ineffective in this setting and may paradoxically enhance tumor growth. The type II RAF inhibitor, tovorafenib (formerly DAY101, TAK-580, MLN2480), has shown promising activity and good tolerability in patients with BRAF-altered pLGG in the phase 2 FIREFLY-1 study, with an objective response rate (ORR) per Response Assessment in Neuro-Oncology high-grade glioma (RANO-HGG) criteria of 67%. Tumor response was independent of histologic subtype, BRAF alteration type (fusion vs. mutation), number of prior lines of therapy, and prior MAPK-pathway inhibitor use. Methods LOGGIC/FIREFLY-2 is a two-arm, randomized, open-label, multicenter, global, phase 3 trial to evaluate the efficacy, safety, and tolerability of tovorafenib monotherapy vs. current standard of care (SoC) chemotherapy in patients
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- 2024
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7. Monosegmental anterior column reconstruction using an expandable vertebral body replacement device in combined posterior–anterior stabilization of thoracolumbar burst fractures
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Dietmar Krappinger, Anna Spicher, Michael Zegg, Max Mueller, Richard A. Lindtner, Rene Schmid, and Christian Kammerlander
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Adult ,Male ,musculoskeletal diseases ,medicine.medical_specialty ,Trauma Surgery ,Posture ,Kyphosis ,Thoracolumbar fracture ,Vertebral body replacement ,Thoracic Vertebrae ,Posterior anterior ,Anterior column reconstruction ,Fracture Fixation, Internal ,03 medical and health sciences ,0302 clinical medicine ,Burst fracture ,Monosegmental ,Humans ,Medicine ,Orthopedics and Sports Medicine ,360° fusion ,Fractures, Comminuted ,Combined posterior–anterior stabilization ,030222 orthopedics ,Lumbar Vertebrae ,business.industry ,Equipment Design ,General Medicine ,Middle Aged ,Surgical correction ,medicine.disease ,Spinal injury ,Radiography ,Vertebral body ,Spinal Fusion ,medicine.anatomical_structure ,Radiological weapon ,Cancellous Bone ,Orthopedic surgery ,Spinal Fractures ,Female ,Surgery ,Tomography, X-Ray Computed ,business ,Nuclear medicine ,Cancellous bone ,030217 neurology & neurosurgery - Abstract
Introduction In combined posterior–anterior stabilization of thoracolumbar burst fractures, the expandable vertebral body replacement device (VBRD) is typically placed bisegmentally for anterior column reconstruction (ACR). The aim of this study, however, was to assess feasibility, outcome and potential pitfalls of monosegmental ACR using a VBRD. In addition, clinical and radiological outcome of monosegmental ACR was related to that of bisegmental ACR using the same thoracoscopic technique. Methods Thirty-seven consecutive neurologically intact patients with burst fractures of the thoracolumbar junction (T11–L2) treated by combined posterior–anterior stabilization were included. Monosegmental ACR was performed in 18 and bisegmental ACR in 19 patients. Fracture type and extent of vertebral body comminution were determined on preoperative CT scans. Monosegmental and bisegmental kyphosis angles were analyzed preoperatively, postoperatively and at final radiological follow-up. Clinical outcome was assessed after a minimum of 2 years (74 ± 45 months; range 24–154; follow-up rate 89.2%) using VAS Spine Score, RMDQ, ODI and WHOQOL-BREF. Results Monosegmental ACR resulted in a mean monosegmental and bisegmental surgical correction of − 15.6 ± 7.7° and − 14.7 ± 8.1°, respectively. Postoperative monosegmental and bisegmental loss of correction averaged 2.7 ± 2.7° and 5.2 ± 3.7°, respectively. Two surgical pitfalls of monosegmental ACR were identified: VBRD positioning (1) onto the weak cancellous bone (too far cranially to the inferior endplate of the fractured vertebra) and (2) onto a significantly compromised inferior endplate with at least two (even subtle) fracture lines. Ignoring these pitfalls resulted in VBRD subsidence in five cases. When relating the clinical and radiological outcome of monosegmental ACR to that of bisegmental ACR, no significant differences were found, except for frequency of VBRD subsidence (5 vs. 0, P = 0.02) and bisegmental loss of correction (5.2 ± 3.7° vs. 2.6 ± 2.5°, P = 0.022). After exclusion of cases with VBRD subsidence, the latter did not reach significance anymore (4.9 ± 4.0° vs. 2.6 ± 2.5°, P = 0.084). Conclusions This study indicates that monosegmental ACR using a VBRD is feasible in thoracolumbar burst fractures if the inferior endplate is intact (incomplete burst fractures) or features only a single simple split fracture line (burst-split fractures). If the two identified pitfalls are avoided, monosegmental ACR may be a viable alternative to bisegmental ACR in selected thoracolumbar burst fractures to spare a motion segment and to reduce the distance for bony fusion.
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- 2018
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8. Pedicle screw anchorage of carbon fiber-reinforced PEEK screws under cyclic loading
- Author
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Werner Schmoelz, Marko Konschake, Richard A. Lindtner, Thomas Nydegger, and Rene Schmid
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Male ,Polymers ,Radiodensity ,Lumbar vertebrae ,Prosthesis Design ,Polyethylene Glycols ,Weight-Bearing ,Benzophenones ,Random Allocation ,03 medical and health sciences ,0302 clinical medicine ,Carbon Fiber ,Pedicle Screws ,Materials Testing ,Cadaver ,medicine ,Peek ,Humans ,Fluoroscopy ,Orthopedics and Sports Medicine ,Pedicle screw ,Aged ,Aged, 80 and over ,Titanium ,Orthodontics ,030222 orthopedics ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Bone Cements ,Biomechanics ,Ketones ,Middle Aged ,Biomechanical Phenomena ,Prosthesis Failure ,Vertebra ,medicine.anatomical_structure ,Female ,Surgery ,Cadaveric spasm ,business ,030217 neurology & neurosurgery - Abstract
Pedicle screw loosening is a common and significant complication after posterior spinal instrumentation, particularly in osteoporosis. Radiolucent carbon fiber-reinforced polyetheretherketone (CF/PEEK) pedicle screws have been developed recently to overcome drawbacks of conventional metallic screws, such as metal-induced imaging artifacts and interference with postoperative radiotherapy. Beyond radiolucency, CF/PEEK may also be advantageous over standard titanium in terms of pedicle screw loosening due to its unique material properties. However, screw anchorage and loosening of CF/PEEK pedicle screws have not been evaluated yet. The aim of this biomechanical study therefore was to evaluate whether the use of this alternative nonmetallic pedicle screw material affects screw loosening. The hypotheses tested were that (1) nonmetallic CF/PEEK pedicle screws resist an equal or higher number of load cycles until loosening than standard titanium screws and that (2) PMMA cement augmentation further increases the number of load cycles until loosening of CF/PEEK screws. In the first part of the study, left and right pedicles of ten cadaveric lumbar vertebrae (BMD 70.8 mg/cm3 ± 14.5) were randomly instrumented with either CF/PEEK or standard titanium pedicle screws. In the second part, left and right pedicles of ten vertebrae (BMD 56.3 mg/cm3 ± 15.8) were randomly instrumented with either PMMA-augmented or nonaugmented CF/PEEK pedicle screws. Each pedicle screw was subjected to cyclic cranio-caudal loading (initial load ranging from − 50 N to + 50 N) with stepwise increasing compressive loads (5 N every 100 cycles) until loosening or a maximum of 10,000 cycles. Angular screw motion (“screw toggling”) within the vertebra was measured with a 3D motion analysis system every 100 cycles and by stress fluoroscopy every 500 cycles. The nonmetallic CF/PEEK pedicle screws resisted a similar number of load cycles until loosening as the contralateral standard titanium screws (3701 ± 1228 vs. 3751 ± 1614 load cycles, p = 0.89). PMMA cement augmentation of CF/PEEK pedicle screws furthermore significantly increased the mean number of load cycles until loosening by 1.63-fold (5100 ± 1933 in augmented vs. 3130 ± 2132 in nonaugmented CF/PEEK screws, p = 0.015). In addition, angular screw motion assessed by stress fluoroscopy was significantly smaller in augmented than in nonaugmented CF/PEEK screws before as well as after failure. Using nonmetallic CF/PEEK instead of standard titanium as pedicle screw material did not affect screw loosening in the chosen test setup, whereas cement augmentation enhanced screw anchorage of CF/PEEK screws. While comparable to titanium screws in terms of screw loosening, radiolucent CF/PEEK pedicle screws offer the significant advantage of not interfering with postoperative imaging and radiotherapy. These slides can be retrieved under Electronic Supplementary Material.
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- 2018
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9. Adaption of neurosurgical resection patterns for pediatric low‐grade glioma spanning two decades—Report from the German LGG‐studies 1996–2018
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Tibor Kelety, Ulrich‐Wilhelm Thomale, Daniela Kandels, Martin U. Schuhmann, Ahmed El Damaty, Jürgen Krauss, Michael C. Frühwald, Pablo Hernáiz Driever, Olaf Witt, Brigitte Bison, Monika Warmuth‐Metz, Torsten Pietsch, René Schmidt, and Astrid K. Gnekow
- Subjects
child ,extent of resection ,low‐grade glioma ,neurosurgery ,treatment algorithm ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Introduction Neurosurgery is considered the mainstay of treatment for pediatric low‐grade glioma (LGG); the extent of resection determines subsequent stratification in current treatment protocols. Yet, surgical radicality must be balanced against the risks of complications that may affect long‐term quality of life. We investigated whether this consideration impacted surgical resection patterns over time for patients of the German LGG studies. Patients and Methods Four thousand two hundred and seventy pediatric patients from three successive LGG studies (median age at diagnosis 7.6 years, neurofibromatosis (NF1) 14.7%) were grouped into 5 consecutive time intervals (TI1‐5) for date of diagnosis and analyzed for timing and extent of first surgery with respect to tumor site, histology, NF1‐status, sex, and age. Results The fraction of radiological LGG diagnoses increased over time (TI1 12.6%; TI5 21.7%), while the extent of the first neurosurgical intervention (3440/4270) showed a reduced fraction of complete/subtotal and an increase of partial resections from TI1 to TI5. Binary logistic regression analysis for the first intervention within the first year following diagnosis confirmed the temporal trends (p
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- 2024
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10. Fracture reduction by postoperative mobilisation for the treatment of hyperextension injuries of the thoracolumbar spine in patients with ankylosing spinal disorders
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Richard A. Lindtner, Rene Schmid, Christian Kammerlander, Michael Goetzen, Dietmar Krappinger, Alexander Keiler, and Davud Malekzadeh
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Male ,Percutaneous ,medicine.medical_treatment ,Fracture reduction ,Hyperextension ,0302 clinical medicine ,Postoperative Complications ,Fracture Fixation ,Orthopedics and Sports Medicine ,Diffuse idiopathic skeletal hyperostosis ,Pain Measurement ,Hyperextension injury ,Aged, 80 and over ,030222 orthopedics ,Hyperostosis, Diffuse Idiopathic Skeletal ,Lumbar Vertebrae ,General Medicine ,Middle Aged ,Treatment Outcome ,Radiological weapon ,Female ,Ankylosing spondylitis ,medicine.medical_specialty ,Trauma Surgery ,Ankylosing spinal disorders ,Outcomes ,Thoracic Vertebrae ,03 medical and health sciences ,Thoracolumbar spine ,medicine ,Humans ,Spondylitis, Ankylosing ,Reduction (orthopedic surgery) ,Percutaneous fixation ,Physical Therapy Modalities ,Aged ,Retrospective Studies ,Postoperative Care ,business.industry ,Spinal fractures ,medicine.disease ,Posterior instrumentation ,Surgery ,Radiography ,Back Pain ,Spinal Injuries ,Orthopedic surgery ,Extension distraction injuries ,business ,030217 neurology & neurosurgery - Abstract
Introduction The aim of this study was to evaluate results of surgical stabilisation of hyperextension injuries of the thoracolumbar spine in patients with ankylosing spinal disorders using two different treatment strategies: the conventional open rigid posterior instrumentation and percutaneous less rigid posterior instrumentation. Surgical and non-surgical complications, the postoperative radiological course, and clinical outcome at final follow-up were comparatively assessed. Moreover, we sought to discuss important biomechanical and surgical aspects specific to posterior instrumentation of the ankylosed thoracolumbar spine as well as to elaborate on the advantages and limitations of the proposed new treatment strategy involving percutaneous less rigid stabilisation and fracture reduction by postoperative mobilisation. Materials and methods Between January 2006 and June 2012, a consecutive series of 20 patients were included in the study. Posterior instrumentation was performed either using an open approach with rigid 6.0 mm bars (open rigid (OR) group) or via a percutaneous approach using softer 5.5 mm bars (percutaneous less rigid (PLR) group). Complications as well as the radiological course were retrospectively assessed, and patient outcome was evaluated at final follow-up using validated outcome scores (VAS Spine Score, ODI, RMDQ, Parker Mobility Score, Barthel Score and WHOQOL-BREF). Results Surgical complications occurred more frequently in the OR group requiring revision surgery in two patients, while there was no revision surgery in the PLR group. The rate of postoperative complications was lower in the PLR group as well (0.7 vs. 1.3 complications per patient, respectively). Fracture reduction and restoration of pre-injury sagittal alignment by postoperative mobilisation occurred within the first 3 weeks in the PLR group, and within 6 months in the OR group. The clinical outcome at final follow-up was very good in both groups with no relevant loss in VAS Spine Score (pain and function), Parker Mobility Score (mobility), and Barthel Index (social independency) compared to pre-operative values. Conclusions This study indicates that the proposed treatment concept involving percutaneous less rigid posterior instrumentation and fracture reduction by postoperative mobilisation is feasible, seems to facilitate adequate reduction and restoration of pre-injury sagittal alignment, and might have the potential to reduce the rate of complications in the management of hyperextension injuries of the ankylosed thoracolumbar spine.
- Published
- 2017
11. The impact of lateral pedicle screw misplacement and subsequent correction of screw trajectory on screw anchorage. A biomechanical analysis
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Peter Ferlic, Richard A. Lindtner, Anna Spicher, Rene Schmid, Richard Bostelmann, Werner Schmoelz, and Michael Zegg
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Orthodontics ,Trajectory ,Neurology. Diseases of the nervous system ,RC346-429 ,Pedicle screw ,Geology - Published
- 2021
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12. Two-sample survival tests based on control arm summary statistics.
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Jannik Feld, Moritz Fabian Danzer, Andreas Faldum, Anastasia Janina Hobbach, and Rene Schmidt
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Medicine ,Science - Abstract
The one-sample log-rank test is the preferred method for analysing the outcome of single-arm survival trials. It compares the survival distribution of patients with a prefixed reference survival curve that usually represents the expected outcome under standard of care. However, classical one-sample log-rank tests assume that the reference curve is known, ignoring that it is frequently estimated from historical data and therefore susceptible to sampling error. Neglecting the variability of the reference curve can lead to an inflated type I error rate, as shown in a previous paper. Here, we propose a new survival test that allows to account for the sampling error of the reference curve without knowledge of the full underlying historical survival time data. Our new test allows to perform a valid historical comparison of patient survival times when only a historical survival curve rather than the full historic data is available. It thus applies in settings where the two-sample log-rank test is not applicable as method of choice due to non-availability of historic individual patient survival time data. We develop sample size calculation formulas, give an example application and study the performance of the new test in a simulation study.
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- 2024
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13. A simple approach for the preoperative assessment of sacral morphology for percutaneous SI screw fixation
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Richard A. Lindtner, Michael Goetzen, Rene Schmid, Michael Blauth, Kevin Ortner, and Dietmar Krappinger
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musculoskeletal diseases ,Sacral morphology ,medicine.medical_specialty ,Percutaneous ,Trauma Surgery ,Preoperative care ,03 medical and health sciences ,Fixation (surgical) ,0302 clinical medicine ,Pelvic ring ,medicine ,Orthopedics and Sports Medicine ,030212 general & internal medicine ,Pelvic ring fracture ,Sacroiliac joint ,030222 orthopedics ,Sacral corridor ,business.industry ,General Medicine ,Nerve injury ,musculoskeletal system ,Sacrum ,body regions ,medicine.anatomical_structure ,Orthopedic surgery ,SI screw fixation ,Surgery ,Radiology ,medicine.symptom ,business - Abstract
Background Percutaneous sacroiliac screw fixation under fluoroscopic control is an effective method for posterior pelvic ring stabilization. However, sacral dysmorphism has a high risk of L5 nerve injury. This study describes a simple method for the preoperative assessment of the sacral morphology using CT scans with widely available tools. Materials and methods CT scans of 1000 patients were analyzed. True inlet, outlet, and lateral views of the sacrum were obtained using a two-dimensional reconstruction tool to align the sacrum in a reproducible manner. Corridor morphology in the inlet view was measured to calculate different morphological types: (1) Ascending type, (2) Horizontal type, and (3) Descending type. In a second step, the corridor was analyzed for the presence of an anterior indentation of the sacrum between the SI joint and the midsagittal plane with proximity to the nerve root L5, which, therefore, may be harmed during screw misplacement. Results A notch was found in the majority of cases with relative frequencies ranging from 69 % (upper quartile of S1) to 95 % (upper quartile of S2). Descending types were, by far, the most frequent corridor type with one exception: In the upper quartile of S1, the ascending type was the most frequent corridor (71 %). Horizontal types were less frequent with a relative incidence between 2 and 14 %. Discussion This study should increase the awareness for sacral dysmorphism, emphasize the importance of a preoperative assessment of the osseous corridor, and provide a simple method for the preoperative assessment with widely available tools.
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- 2016
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14. Spondylotic traumatic central cord syndrome: a hidden discoligamentous injury?
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Verena Kaser, Benjamin Henninger, Michael Zegg, Dietmar Krappinger, Anna Spicher, Rene Schmid, and Richard A. Lindtner
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Joint Instability ,medicine.medical_specialty ,Central Cord Syndrome ,03 medical and health sciences ,Anterior longitudinal ligament ,0302 clinical medicine ,Segmental instability ,medicine ,Humans ,Orthopedics and Sports Medicine ,Aged ,Retrospective Studies ,Hyperextension injury ,030222 orthopedics ,medicine.diagnostic_test ,business.industry ,Cervical hyperextension ,Magnetic resonance imaging ,Middle Aged ,Spinal cord ,Central cord syndrome ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Spinal Injuries ,Cervical Vertebrae ,Surgery ,Neurosurgery ,Radiology ,Spondylosis ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
To revisit the concept of spondylotic traumatic central cord syndrome (TCCS) by assessing the frequency of discoligamentous injury and to correlate magnetic resonance imaging (MRI) and intraoperative findings. A retrospective analysis of twenty-three consecutive patients (mean age: 62.7 ± 14.8 years) with profound spondylotic TCCS after acute cervical hyperextension trauma but without signs of instability on initial CT scans who underwent anterior surgical decompression and fusion was performed. Sensitivity and specificity of MRI in the detection of anterior longitudinal ligament disruption were calculated. The topographic relations between surgically verified segmental instabilities and spinal cord signals on MRI were analyzed. The cervical MRI scans of all patients were evaluated by the radiologist on call at time of admission, re-assessed by a specialized MRI radiologist for the purpose of this study and compared with intraoperative findings. Intraoperative findings revealed 25 cervical spine segments with hyperextension instability in 22 of 23 (95.7%) patients. The radiologist on call correctly assessed segmental hyperextension instability in 15 of 25 segments (sensitivity: 0.60, specificity: 1.00), while the specialized MRI radiologist was correct in 22 segments (sensitivity: 0.88, specificity: 1.00). In 17 of 23 (73.9%) patients, the level of spinal cord signal on MRI matched the level of surgically verified segmental instability. Our findings challenge the traditional concept of spondylotic TCCS as an incomplete cervical spinal cord injury without discoligamentous injury and emphasize the importance of MRI as well as the radiologist’s level of experience for the assessment of segmental instability in these patients. These slides can be retrieved under Electronic Supplementary Material.
- Published
- 2018
15. Functional and radiographic evaluation of an interspinous device as an adjunct for lumbar interbody fusion procedures
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Werner Schmoelz, Niall J.A. Craig, Rene Schmid, Anna Spicher, and Hannes Stofferin
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musculoskeletal diseases ,Rotation ,Spinal stenosis ,Radiography ,Biomedical Engineering ,Pedicle screw instrumentation ,Couple ,03 medical and health sciences ,Centre of rotation ,0302 clinical medicine ,Lumbar ,Lumbar interbody fusion ,medicine ,Humans ,030212 general & internal medicine ,Range of Motion, Articular ,Lumbar Vertebrae ,business.industry ,musculoskeletal system ,medicine.disease ,Internal Fixators ,Spinal Fusion ,Nuclear medicine ,business ,Range of motion ,030217 neurology & neurosurgery - Abstract
In the last decades, several interspinous process devices were designed as a minimally invasive treatment option for spinal stenosis. In order to minimise surgical trauma, interspinous process devices were recently discussed as an alternative posterior fixation in vertebral interbody fusions. Therefore, the purpose of this study was to evaluate the effect of a newly designed interspinous device with polyester bands (PBs) on range of motion (RoM) and centre of rotation (CoR) of a treated motion segment in comparison with an established interspinous device with spikes (SC) as well as with pedicle screw instrumentation in lumbar fusion procedures. Flexibility tests with an applied pure moment load of 7.5 Nm were performed in six monosegmental thoracolumbar functional spinal units (FSUs) in the following states: (a) native, (b) native with PB device, (c) intervertebral cage with PB device, (d) cage with SC and (e) cage with internal fixator. The resulting RoM was normalised to the native RoM. The CoR was determined of X-ray images taken in maximal flexion and extension during testing. In flexion and extension, the PB device without and with the cage reduced the RoM of the native state to 58% [standard deviation (SD) 17.8] and 53% (SD 15.7), respectively. The SC device further reduced the RoM to 27% (SD 16.8), while the pedicle screw instrumentation had the most reducing effect to 17% (SD 17.2) (p
- Published
- 2018
16. Correction to: A simple approach for the preoperative assessment of sacral morphology for percutaneous SI screw fixation
- Author
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Rene Schmid, Dietmar Krappinger, Michael Blauth, Michael Goetzen, Richard A. Lindtner, and Vinzent Kevin Ortner
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Orthodontics ,Male ,Sacrum ,Percutaneous ,business.industry ,Published Erratum ,Bone Screws ,Correction ,Sacroiliac Joint ,General Medicine ,Screw fixation ,Fracture Fixation, Internal ,Fractures, Bone ,Peripheral Nerve Injuries ,Multidetector Computed Tomography ,Preoperative Care ,Medicine ,Humans ,Orthopedics and Sports Medicine ,Surgery ,Female ,business ,Intraoperative Complications ,Simple (philosophy) ,Aged - Abstract
Percutaneous sacroiliac screw fixation under fluoroscopic control is an effective method for posterior pelvic ring stabilization. However, sacral dysmorphism has a high risk of L5 nerve injury. This study describes a simple method for the preoperative assessment of the sacral morphology using CT scans with widely available tools.CT scans of 1000 patients were analyzed. True inlet, outlet, and lateral views of the sacrum were obtained using a two-dimensional reconstruction tool to align the sacrum in a reproducible manner. Corridor morphology in the inlet view was measured to calculate different morphological types: (1) Ascending type, (2) Horizontal type, and (3) Descending type. In a second step, the corridor was analyzed for the presence of an anterior indentation of the sacrum between the SI joint and the midsagittal plane with proximity to the nerve root L5, which, therefore, may be harmed during screw misplacement.A notch was found in the majority of cases with relative frequencies ranging from 69 % (upper quartile of S1) to 95 % (upper quartile of S2). Descending types were, by far, the most frequent corridor type with one exception: In the upper quartile of S1, the ascending type was the most frequent corridor (71 %). Horizontal types were less frequent with a relative incidence between 2 and 14 %.This study should increase the awareness for sacral dysmorphism, emphasize the importance of a preoperative assessment of the osseous corridor, and provide a simple method for the preoperative assessment with widely available tools.
- Published
- 2018
17. Impact Localization for Haptic Input Devices Using Hybrid Laminates with Sensoric Function
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René Schmidt, Alexander Graf, Ricardo Decker, Stephan Lede, Verena Kräusel, Lothar Kroll, and Wolfram Hardt
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impact localization ,localization ,machine learning ,deep learning ,artificial intelligence ,hybrid assembled composite ,Technology - Abstract
The required energy savings can be achieved in all automotive domains through weight savings and the merging of manufacturing processes in production. This fact is taken into account through functional integration in lightweight materials and manufacturing in a process close to large-scale production. In previous work, separate steps of a process chain for manufacturing a center console cover utilizing a sensoric hybrid laminate have been developed and evaluated. This includes the process steps of joining, forming and inline polarization as well as connecting to an embedded system. This work continues the research process by evaluating impact localization methods to use the center console as a haptic input device. For this purpose, different deep learning methods are derived from the state of the art and analyzed for their applicability in two consecutive studies. The results show that MLPs, LSTMs, GRUs and CNNs are suitable to localize impacts on the novel laminate with high localization rates of up to 99%, and thus the usability of the developed laminate as a haptic input device has been proven.
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- 2024
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18. Fragility Fractures Requiring Special Consideration
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Michael Blauth, Rene Schmid, Thomas J. Luger, Michael Zegg, Christian Kammerlander, and Markus Gosch
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Interdisciplinary treatment ,medicine.medical_specialty ,business.industry ,Osteoporosis ,Poison control ,Surgical procedures ,medicine.disease ,Fragility ,Fracture fixation ,Physical therapy ,Medicine ,Geriatrics and Gerontology ,Good outcome ,business ,Fracture type - Abstract
The treatment of osteoporotic vertebral fractures is complicated because of the comorbid conditions of the elderly patient. Underlying osteoporosis leads to malalignment of the weakened bone and impedes fracture fixation. The treatment of osteoporotic vertebral fractures is widely empirical, because standardized and accepted treatment evidence-based concepts are missing for certain fracture types. As in other osteoporotic fractures in the elderly, the key for good outcome may be a combination of interdisciplinary treatment approaches and adapted surgical procedures. This article gives an overview of the underlying problems and possible treatment strategies for treatment of osteoporotic vertebral fractures in geriatric patients.
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- 2014
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19. Wirbelfrakturen bei geriatrischen Patienten
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Christian Kammerlander, Michael Zegg, Rene Schmid, M. Blauth, and Wolfgang Böcker
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Gynecology ,medicine.medical_specialty ,business.industry ,Medicine ,General Medicine ,business - Abstract
ZusammenfassungMit zunehmendem Alter der Bevölkerung kommt es zum Anstieg osteoporotischer Wirbelfrakturen. Aufgrund der vorhandenen Komorbiditäten und der zugrunde liegenden Osteoporose gestaltet sich die medizinische Behandlung der älteren Patienten oft schwierig. Die Osteoporose begünstigt Fehlstellungen des geschwächten Knochens mit funktionellen Folgen. Bis heute erfolgt die Behandlung von osteoporotischen Wirbelfrakturen weitgehend empirisch bedingt durch fehlende evidenzbasierte Konzepte bei speziellen Frakturtypen. Die Kombination von interdisziplinärer Behandlung mit adaptiertem chirurgischem Vorgehen, wie es bei anderen osteoporotischen Frakturen bereits erfolgt, könnte der Schlüssel für ein verbessertes klinisches Ergebnis sein. Diese Arbeit zeigt eine Übersicht der vorhandenen Probleme und der möglichen Behandlungsoptionen osteoporotischer Wirbelfrakturen bei geriatrischen Patienten.
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- 2014
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20. Functional outcome and mortality in geriatric distal femoral fractures
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M. Gosch, P. Riedmüller, Michael Zegg, Christian Kammerlander, Rene Schmid, T. Roth, and U. Kammerlander-Knauer
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Male ,medicine.medical_specialty ,Frail Elderly ,Population ,Comorbidity ,Cohort Studies ,Disability Evaluation ,Fracture Fixation, Internal ,Postoperative Complications ,Quality of life ,Internal medicine ,Fracture fixation ,medicine ,Humans ,education ,Aged ,Retrospective Studies ,General Environmental Science ,Aged, 80 and over ,education.field_of_study ,business.industry ,Mortality rate ,Retrospective cohort study ,Recovery of Function ,Femoral fracture ,Perioperative ,Prognosis ,medicine.disease ,Surgery ,Quality of Life ,General Earth and Planetary Sciences ,Female ,business ,Femoral Fractures ,Osteoporotic Fractures ,Cohort study - Abstract
Background Fragility fractures are a major health care problem worldwide. Due to the ageing population an increase of distal femoral fractures is to be expected. We studied the long-term functional outcome and their influencing factors in geriatric patients with LISS-plated distal femoral fractures. Patients and methods A cohort study with functional long-term follow up examination was carried out in a level one trauma centre on distal femoral fracture patients 65 years and older. Of 53 consecutive patients who were treated in our hospital, 43 patients with a mean age of 80 years met our inclusion criteria. 48.8% died within the study period of 5.3 years. On the remaining patients the residential status, the Barthel index and the Parker score were assessed. Results The mean Barthel index was 47.7 and the mean Parker score was 3.5. 23% were found to be totally housebound and 26% were not able to perform any social activity. Only 18% were able to walk unaided. Patients with any medical complication had significantly higher mortality rates. Patients with extraarticular fractures had better mobility scores. Nursing home residents showed higher mortality rates but compared to patients coming from their own home the difference regarding Barthel and Parker scores remained non-significant. Conclusion This study documents the poor functional long-term outcome of geriatric patients with distal femoral fractures. In comparison to other fragility fracture patients it seems that this population is at higher risk to die in-hospital during their perioperative course. Medical complications have to be avoided as they were found to be associated with worse functional outcome and higher mortality rates. An osteoporosis therapy may be associated with reduced mortality rates also in these patients.
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- 2012
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21. Ein spieltheoretischer Ansatz für das IT-Security-Risikomanagement
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Benjamin Rainer, Rene Schmid, and Stefan Schauer
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Political science ,Humanities - Abstract
Der Beitrag beschreibt die Entwicklung eines Systems fur die Risikoanalyse der Kommunikation in Rechner-Netzwerken. Der Ruckgriff auf spieltheoretische Ansatze fur eine auf Abhorsicherheit bezogene Analyse der Kommunikationsinfrastruktur erlaubt eine systematische Optimierung der Kommunikationsbeziehungen fur einen Betrieb mit minimalem Abhorrisiko. Als Nebenprodukt liefert die spieltheoretische Analyse auch optimale Angriffsszenarien und bietet so wertvolle Entscheidungshilfen fur Verbesserungen an einer gegebenen Kommunikationsinfrastruktur.
- Published
- 2012
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22. Combined posteroanterior fusion versus transforaminal lumbar interbody fusion (TLIF) in thoracolumbar burst fractures
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Richard A. Lindtner, Christian Kammerlander, Michael Blauth, Markus Lill, Rene Schmid, and Dietmar Krappinger
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Adult ,Male ,medicine.medical_specialty ,Bone Screws ,Thoracic Vertebrae ,Young Adult ,Lumbar interbody fusion ,Thoracoscopy ,Humans ,Medicine ,In patient ,Prospective Studies ,Prospective cohort study ,General Environmental Science ,Lumbar Vertebrae ,medicine.diagnostic_test ,business.industry ,Lumbosacral Region ,Middle Aged ,Internal Fixators ,Surgery ,Spinal Fusion ,Concomitant ,Radiological weapon ,Spinal Fractures ,General Earth and Planetary Sciences ,Female ,Observational study ,Anterior approach ,business ,Spinal Cord Compression ,Follow-Up Studies - Abstract
Background The optimal treatment strategy for burst fractures of the thoracolumbar junction is discussed controversially in the literature. Whilst 360° fusion has shown to result in better radiological outcome, recent studies have failed to show its superiority concerning clinical outcome. The morbidity associated with the additional anterior approach may account for these findings. The aim of this prospective observational study was therefore to compare two different techniques for 360° fusion in thoracolumbar burst fractures using either thoracoscopy or a transforaminal approach (transforaminal lumbar interbody fusion (TLIF)) to support the anterior column. Methods Posterior reduction and short-segmental fixation using angular stable pedicle screw systems were performed in all patients as a first step. Monocortical strut grafts were used for the anterior support in the TLIF group, whilst tricortical grafts or titanium vertebral body replacing implants of adjustable height were used in the combined posteroanterior group. At final follow-up, the radiological outcome was assessed by performing X-rays in a standing position. The clinical outcome was measured using five validated outcome scores. The morbidity associated with the approaches and the donor site was assessed as well. Results There were 21 patients in the TLIF group and 14 patients in the posteroanterior group included. The postoperative loss of correction was higher in the TLIF group (4.9° ± 8.3° versus 3.4° ± 6.4°, p > 0.05). There were no significant differences regarding the outcome scores between the two groups. There were no differences in terms of return to employment, leisure activities and back function either. More patients suffered from donor-site morbidity in the TLIF group, whilst the morbidity associated with the surgical approach was higher in the posteroanterior group. Conclusion The smaller donor-site morbidity in the posteroanterior group is counterbalanced by an additional morbidity associated with the anterior approach resulting in similar clinical outcome. Mastering both techniques will allow the spine surgeon to be more flexible in specific situations, for example, in patients with neurological deficits or severe concomitant thoracic trauma.
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- 2012
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23. Mid-term results of PLIF/TLIF in trauma
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Dietmar Krappinger, Anton Kathrein, Michael Blauth, and Rene Schmid
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Radiography ,medicine.medical_treatment ,Mid term results ,Neurosurgical Procedures ,Young Adult ,Humans ,Medicine ,Orthopedics and Sports Medicine ,Prospective Studies ,Prospective cohort study ,Reduction (orthopedic surgery) ,business.industry ,Middle Aged ,Surgery ,Spinal Fusion ,Spinal Injuries ,Radiological weapon ,Spinal fusion ,Spinal Fractures ,Intervertebral fusion ,Female ,Original Article ,Neurosurgery ,business - Abstract
Treatment of thoracolumbar fractures is still controversial. Several treatment options are reported to yield satisfactory results. There is no evidence indicating superiority of any treatment option. We have already presented radiological results of the use of PLIF/TLIF in trauma, which showed satisfactory results concerning intervertebral fusion and acceptable loss of correction. We examined 50 patients regarding loss of correction after implant removal and clinical outcome using a validated visual analogue score. The average time of follow-up (FU) was 35 months. We observed a total loss of correction of 4°. The pre-injury mean VAS score was 92. At FU, there was an average reduction of 17.2 points. Owing to the presented results, we suggest this method as an alternative to combined procedures.
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- 2010
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24. Lumbosacral dislocation: A review of the literature and current aspects of management
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Michael Blauth, Rene Schmid, and Max Reinhold
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Adult ,Male ,musculoskeletal diseases ,Sacrum ,medicine.medical_specialty ,medicine.medical_treatment ,Bone Screws ,Joint Dislocations ,Lumbar vertebrae ,Zygapophyseal Joint ,Fracture Fixation, Internal ,Young Adult ,Rare Diseases ,Fracture fixation ,medicine ,Humans ,Child ,Intervertebral Disc ,Polyradiculopathy ,General Environmental Science ,Intraoperative Care ,Lumbar Vertebrae ,Multiple Trauma ,business.industry ,Anatomy ,medicine.disease ,Spondylolisthesis ,Biomechanical Phenomena ,Radiography ,Spinal Fusion ,medicine.anatomical_structure ,Spinal fusion ,Orthopedic surgery ,Spinal Fractures ,General Earth and Planetary Sciences ,business ,Lumbosacral joint ,Retrolisthesis - Abstract
Lumbosacral fracture dislocation is a very rare lesion and was first described by Watson-Jones in 1940. Two anatomical classifications are described in the literature, all other reports are case presentations. This fracture type is characterised by an antero- or retrolisthesis or a lateral translation of the 5th lumbar vertebra in relation to the sacrum. Biomechanics are discussed controversially. Most patients suffer from a high energy trauma with concomitant severe injuries. There is a high rate of additional neurological deficits. Fractures of the transverse process are thought to be sentinel fractures. MRI and CT scans are essential to detect the whole extent of the lesion. Circumferential fusion is recommended by several authors to regain stability at the lumbosacral junction.
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- 2010
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25. Reposition von Verrenkungen und Verrenkungsbrüchen der unteren Halswirbelsäule
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U. Lange, Christian Knop, Rene Schmid, R. Rosenberger, M. Reinhold, and Michael Blauth
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Adult ,Male ,medicine.medical_specialty ,Adolescent ,Joint Dislocations ,Quadriplegia ,Postoperative Complications ,medicine ,Humans ,Orthopedics and Sports Medicine ,Child ,Radiculopathy ,Spinal Cord Injuries ,Aged ,Neurologic Examination ,Paraplegia ,Gynecology ,business.industry ,Fracture Dislocations ,Recovery of Function ,Middle Aged ,Cervical spine ,Spinal Injuries ,Cervical Vertebrae ,Emergency Medicine ,Spinal Fractures ,Female ,Surgery ,business - Abstract
Traumatic facet dislocations and facet-fracture dislocations in the lower cervical spine (C2/C3 to C7/T1) are frequently associated with devastating neurological symptoms. A good outcome can only be achieved if the operator has wide and sound knowledge of reduction techniques and the best possible strategy is devised for the subsequent treatment of these severe lesions.Between 1973 and 1997 a total of 117 of our patients met at least one of the following inclusion criteria: unilateral locked facet dislocation (48%), bilateral locked facet dislocations (23%), unilateral "perched" facet subluxation (14%), bilateral perched facet subluxation (12%), uni- or bilateral dislocation/perched subluxation with facet fractures (3%).Most of the lesions were located at the levels of C5/C6 and C6/7 (n=46 for each). Associated neurological deficits were present initially in 65% of patients: 35% had complete or incomplete spinal cord injuries (tetraplegia), 2% were paraplegic, and 28% had cervical radiculopathies.Closed reduction (e.g. with the aid of a halo ring) should be carried out as soon as possible after lower cervical spine dislocation or facet-fracture dislocation, as both the success rate of reduction and the potential for recovery from neurological deficits are clearly higher when reduction is achieved within the first 4 h after the initial injury.
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- 2006
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26. Fixateur interne und Wirbelkörperersatz
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Rene Schmid, Christian Knop, Michael Blauth, and M. Reinhold
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Public Health, Environmental and Occupational Health ,Emergency Medicine - Abstract
Die Autoren schildern die Grundlagen aktueller Behandlungskonzepte fur die Verletzungen der Brust- und Lendenwirbelsaule. Unter Bezugnahme auf biomechanische Konzepte und die Klassifikation der Verletzungen werden Erfahrungen und Ergebnisse geschildert, die bis heute erzielt und veroffentlicht wurden. Die Vor- und Nachteile von operativen und nichtoperativen Behandlungskonzepten werden dargestellt. Auserdem schildern die Autoren die verschiedenen Operationsmethoden, die heute zur Anwendung kommen. Erste eigene Ergebnisse mit dem Wirbelkorperersatzimplantat Synex werden vorgestellt.
- Published
- 2005
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27. Spectrum of complications involved in surgical management of spinal injuries: Analysis of two multicenter studies
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Michael Blauth, Rene Schmid, M. Reinhold, and Christian Knop
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Public Health, Environmental and Occupational Health ,Emergency Medicine - Abstract
Die Operationsmethoden in der Wirbelsaulenchirurgie zeigen mit ihren unterschiedlichen Zugangen, Implantaten und Techniken ein groses, sich standig erweiterndes Spektrum. So erlangten zuletzt minimal-invasive Verfahren mit endoskopischer Technik, die Augmentation mit Knochenzement (Vertebro-/Kyphoplastie) und navigierte Eingriffe an der Wirbelsaule („computer-assisted orthopedic surgery“, CAOS) zunehmende Bedeutung. Fehlerquellen der operativen Versorgung von Wirbelsaulenverletzungen betreffen die Lagerung und geschlossenen Reposition, zugangsbedingte Komplikationen, Fehler bei der Dekompression des Spinalkanals, Komplikationen bei der Instrumentierung bzw. Stabilisierung sowie der operativen Fusion. Der vorliegende Beitrag prasentiert die Daten zweier multizentrischer Erhebungsstudien der Arbeitsgemeinschaft „Wirbelsaule“ der Deutschen Gesellschaft fur Unfallchirurgie bezuglich der aufgetretenen Komplikationen und vergleicht diese mit den Ergebnissen einer kurzlich publizierten Metaanalyse.
- Published
- 2005
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28. Fragility fractures requiring special consideration: vertebral fractures
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Christian, Kammerlander, Michael, Zegg, Rene, Schmid, Markus, Gosch, Thomas J, Luger, and Michael, Blauth
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Aged, 80 and over ,Risk Factors ,Frail Elderly ,Humans ,Spinal Fractures ,Comorbidity ,Osteoporotic Fractures ,Aged - Abstract
The treatment of osteoporotic vertebral fractures is complicated because of the comorbid conditions of the elderly patient. Underlying osteoporosis leads to malalignment of the weakened bone and impedes fracture fixation. The treatment of osteoporotic vertebral fractures is widely empirical, because standardized and accepted treatment evidence-based concepts are missing for certain fracture types. As in other osteoporotic fractures in the elderly, the key for good outcome may be a combination of interdisciplinary treatment approaches and adapted surgical procedures. This article gives an overview of the underlying problems and possible treatment strategies for treatment of osteoporotic vertebral fractures in geriatric patients.
- Published
- 2014
29. OF-Pelvis classification of osteoporotic sacral and pelvic ring fractures
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Bernhard W. Ullrich, Klaus J. Schnake, Ulrich J. A. Spiegl, Philipp Schenk, Thomas Mendel, Lars Behr, Philipp Bula, Laura B. Flücht, Alexander Franck, Erol Gercek, Sebastian Grüninger, Philipp Hartung, Cornelius Jacobs, Sebastian Katscher, Friederike Klauke, Katja Liepold, Christian W. Müller, Michael Müller, Georg Osterhoff, Axel Partenheimer, Stefan Piltz, Marion Riehle, Daniel Sauer, Max Joseph Scheyerer, Philipp Schleicher, Gregor Schmeiser, René Schmidt, Matti Scholz, Holger Siekmann, Kai Sprengel, Dietrich Stoevesandt, Akhil Verheyden, Volker Zimmermann, and the Spine Section of the German Society for Orthopaedics and Trauma
- Subjects
Sacral ,Pelvic ring ,Fracture ,Osteoporosis ,Classification ,Consensus development ,Diseases of the musculoskeletal system ,RC925-935 - Abstract
Abstract Objectives Osteoporotic fractures of the pelvis (OFP) are an increasing issue in orthopedics. Current classification systems (CS) are mostly CT-based and complex and offer only moderate to substantial inter-rater reliability (interRR) and intra-rater reliability (intraRR). MRI is thus gaining importance as a complement. This study aimed to develop a simple and reliable CT- and MRI-based CS for OFP. Methods A structured iterative procedure was conducted to reach a consensus among German-speaking spinal and pelvic trauma experts over 5 years. As a result, the proposed OF-Pelvis CS was developed. To assess its reliability, 28 experienced trauma and orthopedic surgeons categorized 25 anonymized cases using X-ray, CT, and MRI scans twice via online surveys. A period of 4 weeks separated the completion of the first from the second survey, and the cases were presented in an altered order. While 13 of the raters were also involved in developing the CS (developing raters (DR)), 15 user raters (UR) were not deeply involved in the development process. To assess the interRR of the OF-Pelvis categories, Fleiss’ kappa (κF) was calculated for each survey. The intraRR for both surveys was calculated for each rater using Kendall’s tau (τK). The presence of a modifier was calculated with κF for interRR and Cohen’s kappa (κC) for intraRR. Results The OF-Pelvis consists of five subgroups and three modifiers. Instability increases from subgroups 1 (OF1) to 5 (OF5) and by a given modifier. The three modifiers can be assigned alone or in combination. In both surveys, the interRR for subgroups was substantial: κF = 0.764 (Survey 1) and κF = 0.790 (Survey 2). The interRR of the DR and UR was nearly on par (κF Survey 1/Survey 2: DR 0.776/0.813; UR 0.748/0.766). The agreement for each of the five subgroups was also strong (κF min.–max. Survey 1/Survey 2: 0.708–0.827/0.747–0.852). The existence of at least one modifier was rated with substantial agreement (κF Survey 1/Survey 2: 0.646/0.629). The intraRR for subgroups showed almost perfect agreement (τK = 0.894, DR: τK = 0.901, UR: τK = 0.889). The modifier had an intraRR of κC = 0.684 (DR: κC = 0.723, UR: κC = 0.651), which is also considered substantial. Conclusion The OF-Pelvis is a reliable tool to categorize OFP with substantial interRR and almost perfect intraRR. The similar reliabilities between experienced DRs and URs demonstrate that the training status of the user is not important. However, it may be a reliable basis for an indication of the treatment score.
- Published
- 2021
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30. Fractures of the pubic rami: a retrospective review of 534 cases
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Michael Blauth, Jakob Kroesslhuber, Dietmar Krappinger, Rene Schmid, and Peter Struve
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Aged, 80 and over ,Male ,Retrospective review ,medicine.medical_specialty ,Pediatrics ,business.industry ,General Medicine ,Pain management ,Surgery ,Survival Rate ,Fractures, Bone ,Mechanism of injury ,Orthopedic surgery ,Cohort ,medicine ,Humans ,Orthopedics and Sports Medicine ,In patient ,Female ,Prospective cohort study ,business ,Survival rate ,Aged ,Pubic Bone - Abstract
Fractures of the pubic rami are typically classified as stable injuries. The current treatment strategies involve pain management and mobilization. However, pain-dependent immobilization may pose a serious hazard to patients with severe preexisting co-morbidities. There is paucity of literature on the outcome and mortality of these patients. We retrospectively analysed 534 patients with these injuries. The following parameters were examined: gender, age, mechanism of injury, fracture pattern, length of hospital stay, care after discharge, number of outpatient follow-ups, and 1-year mortality. Multiple logistic regression analysis was performed for the assessment of factors influencing 1-year mortality. The observed 1-year mortality in the patients group was further compared to a virtual control group with the same age and gender distribution. Women were older and more frequently injured as a result of a simple fall. Age was the only factor to be predictive of 1-year mortality. Mortality increased with higher age in both the patient and the control group, but mortality was higher in the patients group in all age groups. This difference was significant for patients ≥90 years of age. Pubic rami fractures are a heterogeneous cohort of injuries and might not be as benign as thought in patients with severe preexisting co-morbidities. Prospective studies are needed to better gauge the outcome after pubic rami fractures.
- Published
- 2009
31. Internet based multicenter study for thoracolumbar injuries: a new concept and preliminary results
- Author
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M. Reinhold, Rudolf Beisse, Michael Blauth, Lukas P. Staub, Rene Schmid, Christoph Roeder, Volker Bühren, and Christian Knop
- Subjects
Adult ,medicine.medical_specialty ,business.product_category ,Adolescent ,medicine.medical_treatment ,Automatic identification and data capture ,MEDLINE ,Thoracic Vertebrae ,Germany ,medicine ,Internet access ,Humans ,Orthopedics and Sports Medicine ,Operations management ,Prospective Studies ,Real-time data ,Child ,Aged ,Aged, 80 and over ,Computer-assisted surgery ,Internet ,Lumbar Vertebrae ,Data collection ,business.industry ,Data Collection ,Application service provider ,Middle Aged ,Surgery ,Austria ,The Internet ,business - Abstract
This article reports about the internet based, second multicenter study (MCS II) of the spine study group (AG WS) of the German trauma association (DGU). It represents a continuation of the first study conducted between the years 1994 and 1996 (MCS I). For the purpose of one common, centralised data capture methodology, a newly developed internet-based data collection system ( http://www.memdoc.org ) of the Institute for Evaluative Research in Orthopaedic Surgery of the University of Bern was used. The aim of this first publication on the MCS II was to describe in detail the new method of data collection and the structure of the developed data base system, via internet. The goal of the study was the assessment of the current state of treatment for fresh traumatic injuries of the thoracolumbar spine in the German speaking part of Europe. For that reason, we intended to collect large number of cases and representative, valid information about the radiographic, clinical and subjective treatment outcomes. Thanks to the new study design of MCS II, not only the common surgical treatment concepts, but also the new and constantly broadening spectrum of spine surgery, i.e. vertebro-/kyphoplasty, computer assisted surgery and navigation, minimal-invasive, and endoscopic techniques, documented and evaluated. We present a first statistical overview and preliminary analysis of 18 centers from Germany and Austria that participated in MCS II. A real time data capture at source was made possible by the constant availability of the data collection system via internet access. Following the principle of an application service provider, software, questionnaires and validation routines are located on a central server, which is accessed from the periphery (hospitals) by means of standard Internet browsers. By that, costly and time consuming software installation and maintenance of local data repositories are avoided and, more importantly, cumbersome migration of data into one integrated database becomes obsolete. Finally, this set-up also replaces traditional systems wherein paper questionnaires were mailed to the central study office and entered by hand whereby incomplete or incorrect forms always represent a resource consuming problem and source of error. With the new study concept and the expanded inclusion criteria of MCS II 1, 251 case histories with admission and surgical data were collected. This remarkable number of interventions documented during 24 months represents an increase of 183% compared to the previously conducted MCS I. The concept and technical feasibility of the MEMdoc data collection system was proven, as the participants of the MCS II succeeded in collecting data ever published on the largest series of patients with spinal injuries treated within a 2 year period.
- Published
- 2006
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32. Reference curve sampling variability in one-sample log-rank tests.
- Author
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Moritz Fabian Danzer, Jannik Feld, Andreas Faldum, and Rene Schmidt
- Subjects
Medicine ,Science - Abstract
The one-sample log-rank test is the method of choice for single-arm Phase II trials with time-to-event endpoint. It allows to compare the survival of patients to a reference survival curve that typically represents the expected survival under standard of care. The one-sample log-rank test, however, assumes that the reference survival curve is known. This ignores that the reference curve is commonly estimated from historic data and thus prone to sampling error. Ignoring sampling variability of the reference curve results in type I error rate inflation. We study this inflation in type I error rate analytically and by simulation. Moreover we derive the actual distribution of the one-sample log-rank test statistic, when the sampling variability of the reference curve is taken into account. In particular, we provide a consistent estimate of the factor by which the true variance of the one-sample log-rank statistic is underestimated when reference curve sampling variability is ignored. Our results are further substantiated by a case study using a real world data example in which we demonstrate how to estimate the error rate inflation in the planning stage of a trial.
- Published
- 2022
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33. A new risk score for patients after first recurrence of stage 4 neuroblastoma aged ≥18 months at first diagnosis
- Author
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Kiana Kreitz, Angela Ernst, René Schmidt, Thorsten Simon, Matthias Fischer, Ruth Volland, Barbara Hero, and Frank Berthold
- Subjects
clinical trial ,high‐risk neuroblastoma ,recurrence ,relapse ,risk score ,time‐dependent variable ,Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
Abstract Background The prognosis of patients with recurrences from stage 4 neuroblastoma is not uniformly dismal. The evaluation of new therapies therefore needs to consider the individual risks of the treated patients. This study aims to define clinically useful risk criteria. Patients and Methods Inclusion criteria were: first recurrence of neuroblastoma stage 4 aged ≥18 months and enrollment in first line trials between 1997 and 2016. Patients were randomized into a training set (N = 310) and an independent validation set (N = 159). The primary endpoint was secondary event‐free survival. The individual treatment elements the patients received during initial and recurrent disease were analyzed as binary and time‐dependent variables. A five‐step multiple time‐dependent Cox regression analysis was performed on the training set to identify prognostic variables adjusted for the individual frontline treatment. The selected variables resulted in a prognostic index (PI) and were used to build a risk score system. The score was validated with the validation set. Results Of the 469 patients, 372 were treated with curative intent and 97 with palliative intent. The PI included the variables number of recurrence organs (hazard ratio [HR] = 2.27), time to recurrence (HR = 2.03), liver metastasis at diagnosis (HR = 1.77), first recurrence at site of the primary tumor (HR = 1.55), and age (HR = 1.29). Three risk groups were built and confirmed in the validation set. The scoring system was likewise useful for the curatively or palliatively treated subgroups. Conclusion A new risk score system for patients with first recurrence of stage 4 neuroblastoma aged ≥18 months at diagnosis is proposed.
- Published
- 2019
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34. Erratum to: PLIF in thoracolumbar trauma: technique and radiological results
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Dietmar Krappinger, Anton Kathrein, Peter Seykora, Michael Blauth, and Rene Schmid
- Subjects
medicine.medical_specialty ,business.industry ,Radiological weapon ,Medicine ,Orthopedics and Sports Medicine ,Surgery ,Radiology ,Neurosurgery ,Erratum ,business - Published
- 2010
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35. Problematik des Wirbelkörperersatzes mit Spänen und Implantaten
- Author
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Christian Knop, Michael Blauth, M. Reinhold, and Rene Schmid
- Subjects
Public Health, Environmental and Occupational Health ,Emergency Medicine - Published
- 2005
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36. Treatment of children under 4 years of age with medulloblastoma and ependymoma in the HIT2000/HIT-REZ 2005 trials: Neuropsychological outcome 5 years after treatment.
- Author
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Holger Ottensmeier, Paul G Schlegel, Matthias Eyrich, Johannes E Wolff, Björn-Ole Juhnke, Katja von Hoff, Stefanie Frahsek, Rene Schmidt, Andreas Faldum, Gudrun Fleischhack, Andre von Bueren, Carsten Friedrich, Anika Resch, Monika Warmuth-Metz, Jürgen Krauss, Rolf D Kortmann, Udo Bode, Joachim Kühl, and Stefan Rutkowski
- Subjects
Medicine ,Science - Abstract
Young children with brain tumours are at high risk of developing treatment-related sequelae. We aimed to assess neuropsychological outcomes 5 years after treatment. This cross-sectional study included children under 4 years of age with medulloblastoma (MB) or ependymoma (EP) enrolled in the German brain tumour trials HIT2000 and HIT-REZ2005. Testing was performed using the validated Wuerzburg Intelligence Diagnostics (WUEP-D), which includes Kaufman-Assessment-Battery, Coloured Progressive Matrices, Visual-Motor Integration, finger tapping "Speed", and the Continuous Performance Test. Of 104 patients in 47 centres, 72 were eligible for analyses. We assessed whether IQ was impacted by disease extent, disease location, patient age, gender, age at surgery, and treatment (chemotherapy with our without craniospinal irradiation [CSI] or local radiotherapy [LRT]). Median age at surgery was 2.3 years. Testing was performed at a median of 4.9 years after surgery. Patients with infratentorial EPs (treated with LRT) scored highest in fluid intelligence (CPM 100.9±16.9, mean±SD); second best scores were achieved by patients with MB without metastasis treated with chemotherapy alone (CPM 93.9±13.2), followed by patients with supratentorial EPs treated with LRT. In contrast, lowest scores were achieved by patients that received chemotherapy and CSI, which included children with metastasised MB and those with relapsed MB M0 (CPM 71.7±8.0 and 73.2±21.8, respectively). Fine motor skills were reduced in all groups. Multivariable analysis revealed that type of treatment had an impact on IQ, but essentially not age at surgery, time since surgery or gender. Our results confirm previous reports on the detrimental effects of CSI in a larger cohort of children. Comparable IQ scores in children with MB treated only with chemotherapy and in children with EP suggest that this treatment strategy represents an attractive option for children who have a high chance to avoid application of CSI. Longitudinal follow-up examinations are warranted to assess long-term neuropsychological outcomes.
- Published
- 2020
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37. Molecular Classification Substitutes for the Prognostic Variables Stage, Age, and MYCN Status in Neuroblastoma Risk Assessment
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Carolina Rosswog, Rene Schmidt, André Oberthuer, Dilafruz Juraeva, Benedikt Brors, Anne Engesser, Yvonne Kahlert, Ruth Volland, Christoph Bartenhagen, Thorsten Simon, Frank Berthold, Barbara Hero, Andreas Faldum, and Matthias Fischer
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 - Abstract
BACKGROUND: Current risk stratification systems for neuroblastoma patients consider clinical, histopathological, and genetic variables, and additional prognostic markers have been proposed in recent years. We here sought to select highly informative covariates in a multistep strategy based on consecutive Cox regression models, resulting in a risk score that integrates hazard ratios of prognostic variables. METHODS: A cohort of 695 neuroblastoma patients was divided into a discovery set (n = 75) for multigene predictor generation, a training set (n = 411) for risk score development, and a validation set (n = 209). Relevant prognostic variables were identified by stepwise multivariable L1-penalized least absolute shrinkage and selection operator (LASSO) Cox regression, followed by backward selection in multivariable Cox regression, and then integrated into a novel risk score. RESULTS: The variables stage, age, MYCN status, and two multigene predictors, NB-th24 and NB-th44, were selected as independent prognostic markers by LASSO Cox regression analysis. Following backward selection, only the multigene predictors were retained in the final model. Integration of these classifiers in a risk scoring system distinguished three patient subgroups that differed substantially in their outcome. The scoring system discriminated patients with diverging outcome in the validation cohort (5-year event-free survival, 84.9 ± 3.4 vs 63.6 ± 14.5 vs 31.0 ± 5.4; P
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- 2017
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38. Comparison of Spot Sign, Blend Sign and Black Hole Sign for Outcome Prediction in Patients with Intracerebral Hemorrhage
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Peter B. Sporns, Michael Schwake, André Kemmling, Jens Minnerup, Wolfram Schwindt, Thomas Niederstadt, Rene Schmidt, and Uta Hanning
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cerebral hemorrhage ,computed tomography ,stroke ,hematoma ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background and Purpose Blend sign (BS) and black hole sign (BHS) on non-contrast computed tomography (NCCT) and spot sign (SS) on CT-angiography (CTA) are indicators of early hematoma expansion in spontaneous intracerebral hemorrhage (ICH). However, their independent contributions to outcome have not been well explored. Methods In this retrospective study, inclusion criteria were: 1) spontaneous ICH and 2) NCCT and CTA performed on admission within 6 hours after onset of symptoms. Discharge outcome was dichotomized as good (modified Rankin Scale [mRS] 0-3) and poor (mRS 4-6) outcomes. The impacts of BHS, BS and SS on outcome were assessed in univariate and multivariable logistic regression models. Results Of 182 patients with spontaneous ICH, 26 (14.3%) presented with BHS, 37 (20.3%) with BS and 39 (21.4%) with SS. There was a substantial correlation between SS and BS (κ=0.701) and a moderate correlation between SS and BHS (κ=0.424). In univariable logistic regression, higher baseline hematoma volume (P
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- 2017
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39. Bacteraemia and fungaemia in cystic fibrosis patients with febrile pulmonary exacerbation: a prospective observational study
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Joerg Grosse-Onnebrink, Florian Stehling, Eva Tschiedel, Margarete Olivier, Uwe Mellies, Rene Schmidt, Jan Buer, Peter-Micheal Rath, and Joerg Steinmann
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Diseases of the respiratory system ,RC705-779 - Abstract
Abstract Background Bloodstream pathogens can be identified by multiplex PCR (SeptiFast (SF)) or blood culture (BC); whether these pathogens are present in cystic fibrosis (CF) patients during febrile pulmonary exacerbations (FPE) has not been sufficiently studied. Methods In this prospective observational study, blood from CF patients experiencing FPE was tested with SF and BC before the initiation of antibiotic treatment. Results After contaminants had been excluded, 9 of 72 blood samples tested positive by BC or SF. SF exclusively detected four pathogens; BC, one. Pulmonary pathogen transmission was likely in all cases except for 2 cases of candidaemia, which were believed to be caused by catheter-related infections. For three cases, test results caused us to change the antibiotic regimen. Sensitivity (85.7% vs. 42.9%) and negative predictive value (98.4% vs. 87.0%) tended to be higher for SF than for BC. Conclusions The results of SF and BC show that bacteraemia and fungaemia are present in CF patients during FPE and may affect antibiotic therapy. SF can help rule out catheter-related bloodstream infections.
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- 2017
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40. 5033166 Method and device for the disposal of waste in a fiber cleaning machine
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Martin Kyburz, Peter Anderegg, and Rene Schmid
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Waste management ,business.industry ,Environmental science ,A fibers ,Process engineering ,business ,General Environmental Science - Published
- 1992
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41. Monitoring the Structural Health of Glass Fibre-Reinforced Hybrid Laminates Using Novel Piezoceramic Film
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René Schmidt, Alexander Graf, Ricardo Decker, Michael Heinrich, Verena Kräusel, Lothar Kroll, and Wolfram Hardt
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hybrid assembled composite ,piezoceramic compound ,fibre metal laminates ,fatigue ,signal processing ,Chemical technology ,TP1-1185 - Abstract
This work investigates a new generation structural health monitoring (SHM) system for fibre metal laminates (FML) based on an embedded thermoplastic film with compounded piezoceramics, termed piezo-active fibre metal laminate (PFML). The PFML is manufactured using near-series processes and its potential as a passive SHM system is being investigated. A commercial Polyvinylidene fluoride (PVDF) sensor film is used for comparative evaluation of the sensor signals. Furthermore, thermoset and thermoplastic-based FML are equipped with the sensor films and evaluated. For this purpose, static and dynamic three-point bending tests are carried out and the data are recorded. The data obtained from the sensors and the testing machine are compared with the type and time of damage by means of intelligent signal processing. By using a smart sensor system, further investigations are planned which the differentiation between various failure modes, e.g., delamination or fibre breakage.
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- 2020
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42. Is there a 'weekend effect' in kidney transplantation?
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Katharina Schütte-Nütgen, Gerold Thölking, Maximilian Dahmen, Felix Becker, Linus Kebschull, René Schmidt, Hermann Pavenstädt, Barbara Suwelack, and Stefan Reuter
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Medicine ,Science - Abstract
The 'weekend effect' describes increased adverse outcomes after weekend hospitalization. We examined weekend-weekday differences in the outcome of 580 patients following renal transplantation (RTx, brain dead donors) between January 2007 and December 2014 at our center. 3-year patient and graft survival, incidence of delayed graft function (DGF), acute rejections and estimated glomerular filtration rate (eGFR, CKD-EPI) at 1 year as well as surgical complications were assessed. Of all 580 transplants, 416 (71.7%) were performed on weekdays (Monday-Friday) and 164 (28.3%) on weekends (Saturday-Sunday). 3-year patient and graft survival, frequencies of DGF, acute rejections and 1-year eGFR as well as length of hospital stay were similar between RTx patients transplanted on weekdays or weekends, respectively. However, a noticeable difference was detected with regard to surgical complications which were more frequent in RTx patients transplanted on weekends. All results remained consistent across all definitions of weekend status. Our results suggest that weekend transplant status does not affect functional short-term and long-term outcomes after RTx. The standardized protocols and operationalized processes applied in RTx might contribute to this finding and may provide a model for other medical procedures that are performed on weekends to improve efficiency and outcomes. The higher rate of surgical complications after weekend RTx needs further elaboration to fully assess the presence of a weekend effect in RTx.
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- 2017
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43. A Comparison of Different Algorithms for the Assessment of Cardiovascular Risk in Patients at Waiting List for Kidney Transplantation.
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Stefan Reuter, Stefanie Reiermann, Viola Malyar, Katharina Schütte-Nütgen, Renè Schmidt, Hermann Pavenstädt, Holger Reinecke, and Barbara Suwelack
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Medicine ,Science - Abstract
Cardiovascular disease (CVD) is the leading cause of death after renal transplantation with a high prevalence in dialysis patients. It is still a matter of debate how to assess the cardiovascular risk in kidney transplant candidates. Several approaches and scores exist and found their way into the guidelines.We herein assessed PROCAM, Framingham, ESC-SCORE and our own dedicated algorithm in patients applying for renal transplantation at our transplantation center between July 2006 and August 2009. Data of 347 consecutive patients were recorded at baseline and during a follow-up of 4.1 years regarding cardiovascular (CV) events and event-free and overall survival. During follow-up 31 (8.9%) patients died, 24 (6.9%) myocardial infarctions occurred and 19 (5.5%) patients received a new diagnosis of cerebrovascular disease. Predictors for event-free survival identified by univariable Cox regression analysis were age at start of dialysis, ESC-SCORE as well as our own score. Final multivariable model with a stepwise model building procedure revealed age at start of dialysis and smoking to be prognostic for event-free (hazard ratio 1.07/year and 2.15) and overall survival (1.10/year and 3.72).Comparison of CV risk assessment scores showed that ESC-SCORE most robustly predicted event-free and overall survival in our cohort. We conclude that CV risk assessment by ESC-SCORE can be reasonably performed in kidney transplant candidates.
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- 2016
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44. Eficiência térmica de telhas onduladas de fibrocimento aplicadas em abrigos individuais para bezerros expostos ao sol e à sombra Thermal efficiency of fiber cement corrugated sheets applied to individual housing for calves exposed to sun and shade
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Juliano Fiorelli, Rene Schmidt, Celso Yoji Kawabata, Celso Eduardo Lins de Oliveira, Holmer Savastano Junior, and João Adriano Rossignolo
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bezerreiro ,conforto térmico ,termografia infravermelho ,housing for calves ,infrared thermograph ,thermal comfort ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
Este trabalho apresenta um estudo da eficiência térmica de coberturas de bezerreiros individuais expostas ao sol e à sombra, por meio de termografia infravermelha, temperatura interna e índices de conforto térmico. Foram avaliados quatro bezerreiros, três expostos ao sol, a saber: (i) cobertos com telhas de fibrocimento sem amianto - pintadas de branco, (ii) sem pintura e (iii) com sombrite posicionado internamente aos bezerreiros, à distância de 0,10m da face inferior da telha. O quarto bezerreiro foi instalado em área sombreada e coberto com telhas de fibrocimento sem pintura. As coletas de dados foram realizadas durante 21 dias, nos horários das 11h00min, 14h00min e 17h00min. Os resultados mostraram variações significativas na temperatura de superfície das coberturas e nos índices de conforto térmico, entre os tratamentos expostos ao sol e à sombra, para todos os horários avaliados. As imagens termográficas infravermelhas mostraram-se eficientes para melhor compreensão dos processos de transferência de calor da cobertura para o interior das instalações.This research presents a study of roof thermal efficiency in individual housing for calves exposed to sun and shade through infrared thermography, internal temperature and thermal comfort indexes. Four different individual housing for calves covered with asbestos-free fiber-cement corrugated sheets were evaluated. Three of them were directly exposed to the sun: (i) corrugated sheets painted white in the external surface, (ii) corrugated sheets without painting and (iii) with screen shade fabric installed 0.10m under de internal surface of the corrugated sheet. The fourth individual housing was installed in the shade area and covered with unpainted corrugated fiber-cement sheets. The analysis was taken for 21 days at 11h00min, 14h00min and 17h00min. The results indicate significant variations in the roofing surface temperature and thermal comfort indexes among the treatments exposed to the sun and shade, for all the evaluations during the day. The infrared thermography images were effective for better understanding the heat transfer processes from the roof to the internal environment of the housing.
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- 2012
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45. Hybrid Laminate for Haptic Input Device with Integrated Signal Processing
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René Schmidt, Alexander Graf, Ricardo Decker, Verena Kräusel, Wolfram Hardt, Dirk Landgrebe, and Lothar Kroll
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hybrid laminate ,piezoceramic compound ,sensor function ,sheet metal forming ,impact detection ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Achieving lightweight construction through only material substitution does not realize the full potential of producing a lightweight material, hence, it is no longer sufficient. Weight-saving goals are best achieved through additional function integration. In order to implement this premise for mass production, a manufacturing process for joining and forming hybrid laminates using a new tool concept is presented. All materials used are widely producible and processable. The manufactured cover of an automotive center console serves to demonstrate a human interface device with impact detection and action execution. This is only possible through a machine learning system, which is implemented on a small—and thus space- and energy-saving—embedded system. The measurement results confirm the objective and show that localization was sufficiently accurate.
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- 2018
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46. PLIF in thoracolumbar trauma: technique and radiological results.
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Schmid R, Krappinger D, Seykora P, Blauth M, and Kathrein A
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- Adolescent, Adult, Aged, Bone Screws, Female, Fracture Fixation, Internal instrumentation, Fracture Fixation, Internal methods, Humans, Internal Fixators, Lumbar Vertebrae diagnostic imaging, Lumbar Vertebrae injuries, Male, Middle Aged, Radiography, Retrospective Studies, Spinal Fractures diagnostic imaging, Spinal Fusion instrumentation, Statistics, Nonparametric, Thoracic Vertebrae diagnostic imaging, Thoracic Vertebrae injuries, Treatment Outcome, Lumbar Vertebrae surgery, Spinal Fractures surgery, Spinal Fusion methods, Thoracic Vertebrae surgery
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Patients with fractures from the 11th thoracic to the 5th lumbar vertebra had a reconstruction of the anterior column with monocortical iliac crest autograft by using a single dorsal approach. The loss of correction was observed using X-rays pre- and post-operatively, at 3 months and after implant removal (IR). Successful fusion was assessed using computed tomography after the implant removal. To assess the loss of correction and intervertebral fusion rate of this technique. There are still controversial discussions about the treatment modalities of spine lesions, especially in cases of burst fractures. Dorsal, combined and ventral procedures are reported with different assets and drawbacks. We want to present a method to restore the weight-bearing capability of the anterior column using a single dorsal approach. From 2001 to 2005, a total of 100 patients was treated with this technique at our department. Follow-up examination was possible in 82 patients. The X-rays and CT scans were proofed for loss of correction and fusion rate. The anterior column has been restored using a monocortical strut graft via a partial resection of the lamina and the apophyseal joint on one side to access the disc space. The dorsal reduction has been achieved using an angular stable pedicle screw system. The mean follow-up time was 15 months (range 8-39); 67 patients had a CT scan at follow-up and 83% showed a 360 degrees fusion. The average post-operative loss of correction was 3.3 degrees (range 0-21). The average duration of operation was 192 min (range 120-360) and the mean blood loss was 790 ml (range 300-3,400 ml). Regarding the complications we did not have any deep wound infections. We had two epidural haematomas postoperatively with a neurological deterioration that had to be revised. We were able to decompress the neurological structures and restore the weight-bearing capability of the anterior column in a one-stage procedure. So we think that this technique can be an alternative procedure to combined operations regarding the presented radiological results of successful fusion and loss of correction.
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- 2010
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