University of Aachen Medical Center

Aachen, Germany

University of Aachen Medical Center

Aachen, Germany
Time filter
Source Type

Thudium M.O.,University of Bonn | Campos A.R.,University of Bonn | Campos A.R.,Hospital Of Santa Maria Avenida | Urbach H.,University of Bonn | And 2 more authors.
Neurosurgery | Year: 2010

BACKGROUND: Visual field defects are a common side effect after mesial temporal resections such as selective amygdalohippocampectomy (SelAH). OBJECTIVE: To present a method of diffusion tensor tractography (DTT) of the Meyer loop for preoperative planning of the surgical approach for SelAH and for intraoperative visualization on a navigation-guided operating microscope. METHODS: Twelve patients were selected for SelAH to treat mesial temporal lobe epilepsy. All received preoperative MRI with diffusion tensor imaging sequences. The Meyer loop was determined and reconstructed as an object with DTT. Images were utilized for preoperative planning in which a safe approach not affecting the Meyer loop was specified. A navigation-guided operating microscope was used for image-guided surgery. RESULTS: DTT was a reliable method for visualization of the Meyer loop. Reconstruction of the Meyer loop had a direct impact on the approach planning. In all 12 cases, the optic tract could only be spared using a basal approach. Ten patients underwent SelAH by the subtemporal approach, and 2 underwent SelAH by the transcortical approach through the inferior temporal gyrus. During the critical early phase of the operation image guidance remained accurate until entry into the ventricle. Nine of 12 patients had no postoperative field deficits (75%). Three patients (25%) experienced peripheral incomplete quadrantanopia. CONCLUSION: DTT and intraoperative visualization of the Meyer loop is a helpful tool for preoperative planning and during surgery to find a safe trajectory to mesial temporal structures while avoiding the optic radiation. This technique in combination with a basal approach seems to be a promising strategy to prevent postoperative visual field deficits in most patients. Copyright © 2010 by the Congress of Neurological Surgeons.

Wiese A.,Aachen University Medical Center | Wiese A.,University of Aachen Medical Center | Pape H.C.,University of Pittsburgh
Orthopedic Clinics of North America | Year: 2010

Bone defects represent a difficult problem for the clinician. They entail a sustained increase in hospitalization, risk of complications, and associated increase in expenses. This article discusses bone defects caused by high-energy injuries, bone loss, infected nonunions, and nonunions. © 2010 Elsevier Inc. All rights reserved.

Zelle B.A.,University of Texas Health Science Center at San Antonio | Bhandari M.,McMaster University | Sanchez A.I.,University of Pittsburgh | Probst C.,Witten/Herdecke University | Pape H.-C.,University of Aachen Medical Center
Journal of Orthopaedic Trauma | Year: 2013

Background: Loss of follow-up represents a potential source of bias. Suggested guidelines propose 20% loss of follow-up as acceptable. However, these guidelines have not been established through scientific investigations. The goal of this study was to evaluate how loss of follow-up influences the statistical significance in a trauma database. Methods: A database of 637 polytrauma patients with an average follow-up of 17.5 years postinjury was used. The functional outcome of workers' compensation patients versus nonworkers' compensation patients was compared using a validated scoring system. A significant difference between the 2 groups was found (P < 0.05). We simulated a gradually increasing loss of follow-up by randomly deleting an increasing number of patients from 2%, 5%, and 10%, and then increasing in increments of 5% until the significance changed. This process was repeated 50 times, each time with a different electronic random generator. For each simulation series, we documented at which simulated loss of follow-up that the results turned from significant (P < 0.05) to nonsignificant (P > 0.05). Results: Among 50 simulation series, the turning point from significant to nonsignificant varied between 15% and 75% loss of follow-up. A simulated loss of follow-up of 10% did not change the statistical significance in any of the simulation series; a simulated loss of follow-up of 20% changed the statistical significance in 28% of our simulation series. Conclusions: A loss of follow-up of 20% or less may frequently change the study results. Researchers should establish protocols to minimize loss of follow-up and clearly state the loss of follow-up in manuscript publications. Copyright © 2013 by Lippincott Williams & Wilkins.

Rein D.T.,University of Duesseldorf Medical Center | Schmidt T.,PAN Clinic | Hess A.P.,University of Duesseldorf Medical Center | Volkmer A.,University of Duesseldorf Medical Center | And 2 more authors.
Journal of Minimally Invasive Gynecology | Year: 2011

Study Objective: The aim of this study was to estimate the rate of intrauterine adhesions and subsequent pregnancy outcome in patients with residual trophoblastic tissue treated with hysteroscopic resection versus ultrasound-guided dilation and evacuation (D&E). Design: Cohort study from 2 centers (Canadian Task Force classification II-2). Setting: Two surgical teams at the University of Duesseldorf Medical Center and the PAN Clinic in Cologne, Germany. Patients: Women with residual trophoblastic tissue after first- or second-trimester miscarriage or term delivery. Intervention: Two techniques were used for the removal of residual trophoblastic tissue: ultrasound-guided evacuation with a curette (D&E) and hysteroscopic resection of trophoblastic tissue (HR). Measurements and Main Results: We evaluated 95 patients who underwent secondary intervention for residual trophoblastic disease. A total of 42 patients underwent dilation of the cervix and ultrasound-guided curettage. In a second series of 53 patients, a resectoscope fitted with a 4-mm cutting loop was used for the removal of residual trophoblastic tissue used without application of current. Three months after the intervention, second-look office hysteroscopy was performed. Differences between both treatment groups were statistically significant. After HR, mild intrauterine adhesions were found in 2 patients (4.2%). After D&E, 12 patients (30.8%) presented with intrauterine adhesions (mild intrauterine adhesions: n = 7 [17.9%]; single dense adhesions: n = 3 [7.7%]; and extensive endometrial fibrosis n = 1 [2.6%]). Eighty-two patients wanted to become pregnant. Conception rate of all patients examined was 68.8% (HR) and 59.9% (D&E) (p < .05). In patients younger than 35 years of age who underwent HR, the pregnancy rate was significantly (p < .05) increased compared with patients who underwent D&E (78.1% vs 66.6%). In addition, patients from the HR group demonstrated a significantly (p < .05) shorter time to conception (11.5 month vs 14.5 month). Conclusion: The results of this study indicate that selective HR of residual trophoblastic tissue significantly reduces the incidence of intrauterine adhesions and increases pregnancy rates. © 2011 AAGL.

Dienstknecht T.,University of Aachen Medical Center | Rixen D.,Trauma Hospital | Giannoudis P.,University of Leeds | Pape H.-C.,University of Aachen Medical Center | Pape H.-C.,University of Pittsburgh
Clinical Orthopaedics and Related Research | Year: 2013

Background: In multiply injured patients, definitive stabilization of major fractures is performed whenever feasible, depending on the clinical condition. Questions/purposes: We therefore asked whether (1) any preoperative indicators predict major complications after major extremity surgery; (2) perioperative routine parameters other than those indicative of hemorrhagic shock predict postoperative complications; and (3) any postoperative clinical findings can predict major complications in the further course of the patient. Methods: We prospectively followed patients with femoral midshaft fracture, Injury Severity Score (ISS) > 16 points, or three fractures and Abbreviated Injury Scale (AIS) ≥ 2 points and another injury (AIS ≥ 2 points), and age 18 to 65 years. We recorded multiple clinical parameters. End points were pneumonia, sepsis, acute respiratory distress syndrome, acute lung injury, and multiple organ failure. Results: Forty-three of 165 patients developed complications. (1) Patients with complications had a decreased initial Glasgow Coma Scale and tended to have a lower ISS. (2) None of the assessed perioperative parameters was able to sufficiently predict postoperative complications. (3) The presence of a lung contusion and ventilation > 48 hours were associated with complications in the further course. Conclusions: In stable multiply injured patients, none of the individual routine clinical parameters was able to predict complications. Severe head and thoracic injuries seem to be important drivers for the development postoperative complications. Level of Evidence: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence. © 2013 The Association of Bone and Joint Surgeons®.

Gradl G.,University of Aachen Medical Center | Knobe M.,University of Aachen Medical Center | Pape H.-C.,University of Aachen Medical Center | Neuhaus P.V.,Massachusetts General Hospital | And 2 more authors.
International Orthopaedics | Year: 2014

Purpose: The aim of this study was to analyse the factors that influence surgeon decision-making in the treatment of proximal humerus fractures that might be considered for arthroplasty or open reduction and internal fixation. Methods: A total of 217 surgeons evaluated radiographs and clinical vignettes of ten patients with fractures of the proximal humerus. In addition to radiographs, we provided patient age, sex, trauma mechanism, activity level (sedentary-vigorously active), and physical status (normal healthy-moribund). Observers were asked to: (1) choose open reduction and internal fixation or hemiarthroplasty (closed question, one option) and (2) to briefly describe the factors that led to their decision (open-ended question). We assessed interobserver reliability using the Fleiss generalized kappa and analysed factors that influenced decision-making according to treatment choice. Results: Internal fixation was the preferred treatment for the majority of fractures. The overall multirater agreement was fair (κ = 0.30), with a 75 % proportion of agreement. When asked to describe the factors that influenced decision-making, surgeons favouring internal fixation described patient-based factors in 52 %, fracture morphology in 51 %, surgeon factors in 42 %, and bone quality in 11 %. In contrast, fracture morphology was the most common factor (67 %) described by surgeons recommending replacement. Patient age, sex, activity level, physical status and the presence of angular displacement were associated with a recommendation for internal fixation. Conclusion: There is substantial variation in recommendations for internal fixation vs. arthroplasty for fractures of the proximal humerus that arises in large part from patient and surgeon factors. © 2014, SICOT aisbl.

Pfeifer R.,University of Aachen Medical Center | Pfeifer R.,University of Pittsburgh | Darwiche S.,University of Pittsburgh | Kohut L.,University of Pittsburgh | And 2 more authors.
Clinical Orthopaedics and Related Research | Year: 2013

Background: In multiply injured patients, bilateral femur fractures invoke a substantial systemic inflammatory impact and remote organ dysfunction. However, it is unclear whether isolated bone or soft tissue injury contributes to the systemic inflammatory response and organ injury after fracture. Questions/purposes: We therefore asked whether the systemic inflammatory response and remote organ dysfunction are attributable to the bone fragment injection, adjacent soft tissue injury, or both. Methods: Male C57/BL6 mice (8-10 weeks old, 20-30 g) were assigned to four groups: bone fragment injection (BF, n = 9) group; soft tissue injury (STI, n = 9) group; BF + STI (n = 9) group, in which both insults were applied; and control group, in which neither insult was applied. Animals were sacrificed at 6 hours. As surrogates for systemic inflammation, we measured serum IL-6, IL-10, osteopontin, and alanine aminotransferase (ALT) and nuclear factor (NF)-κB and myeloperoxidase (MPO) in the lung. Results: The systemic inflammatory response (mean IL-6 level) was similar in the BF (61.8 pg/mL) and STI (67.9 pg/mL) groups. The combination (BF + STI) of both traumatic insults induced an increase in mean levels of inflammatory parameters (IL-6: 189.1 pg/mL) but not in MPO levels (1.21 ng/mL) as compared with the BF (0.82 ng/mL) and STI (1.26 ng/mL) groups. The model produced little evidence of remote organ inflammation. Conclusions: Our findings suggest both bone and soft tissue injury are required to induce systemic changes. The absence of remote organ inflammation suggests further fracture-associated factors, such as hemorrhage and fat liberation, may be more critical for induction of remote organ damage. Clinical Relevance: Both bone and soft tissue injuries contribute to the systemic inflammatory response. © 2013 The Association of Bone and Joint Surgeons®.

Pfeifer R.,University of Pittsburgh | Kobbe P.,University of Aachen Medical Center | Darwiche S.S.,University of Pittsburgh | Billiar T.R.,University of Pittsburgh | Pape H.-C.,University of Aachen Medical Center
Journal of Orthopaedic Research | Year: 2011

This study was performed to analyze the role of hemorrhage-induced hypotension in the induction of systemic inflammation and remote organ dysfunction. Male C57/BL6 mice (6- to 10-week old and 20-30g) were used. Animals were either subjected to pseudo-fracture [PF; standardized soft-tissue injury and injection of crushed bone, PF group: n = 9], or PF combined with hemorrhagic shock (HS+PF group: n = 6). Endpoint was 6h. Systemic inflammation was assessed by IL-6 and IL-10 levels. Myeloperoxidase (MPO) and NF-κB activity in the lung and liver tissue were obtained to assess remote organ damage. The increases of systemic cytokines are similar for animals subjected to PF and PF+HS (IL-6: 189pg/ml±32.5 vs. 160pg/ml±5.3; IL-10: 60.3pg/ml± 15.8 vs. 88pg/ml±32.4). Furthermore, the features (ALT; NF-κB) of liver injury are equally elevated in mice subjected to PF (76.9U/L±4.5) and HS+ PF (80U/L±5.5). Lung injury, addressed by MPO activity was more severe in group HS+ PF (2.95ng/ml±0.32) than in group PF (1.21ng/ml±0.2). Both PF and additional HS cause a systemic inflammatory response. In addition, hemorrhage seems to be associated with remote affects on the lung. © 2010 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Gradl G.,University of Aachen Medical Center | Neuhaus V.,University of Aachen Medical Center | Fuchsberger T.,University of Aachen Medical Center | Guitton T.G.,University of Aachen Medical Center | And 2 more authors.
Journal of Hand Surgery | Year: 2013

Purpose: To evaluate the reliability and accuracy of diagnosis of scapholunate dissociation (SLD) among AO type C (compression articular) fractures of the distal radius. Methods: A total of 217 surgeons evaluated 21 sets of radiographs with type C fractures of the distal radius for which the status of the scapholunate interosseous ligament was established by preoperative 3-compartment computed tomographic arthrography with direct operative visualization of diagnosed SLD (reference standard). Observers were asked whether SLD was present, and if yes, whether they would recommend operative treatment. Diagnostic performance characteristics were calculated with respect to the reference standard. We assessed interobserver reliability using the Fleiss generalized kappa. Results: The interobserver agreement for radiographic diagnosis of SLD was moderate (κ = 0.44). Correct diagnosis for a given set of radiographs ranged from 8% to 98% (average, 79%) of observers. Diagnostic performance characteristics were: 69% sensitivity, 84% specificity, 84% accuracy, 68% positive predictive value, and 84% negative predictive value. Based on a prevalence of 5%, Bayes adjusted positive and negative predictive values were 18% and 98%, respectively. Raters recommended operative treatment in 74% to 100% of patients diagnosed with SLD. Conclusions: Radiographs are moderately reliable and are better at ruling out than ruling in SLD associated with type C fracture of the distal radius. Type of study/level of evidence: Diagnostic III. © 2013 American Society for Surgery of the Hand.

Sturm J.A.,Akademie der Unfallchirurgie AUC | Pape H.-C.,University of Aachen Medical Center | Dienstknecht T.,University of Aachen Medical Center
Clinical Orthopaedics and Related Research | Year: 2013

Background: Development of trauma systems is a demanding process. The United States and Germany both have sophisticated trauma systems. This manuscript is a summary of political, economic, and medical changes that have led to the development of both trauma systems and the current high-quality standards. Questions/purposes: We specifically asked three questions: (1) What tasks are involved in developing a modern trauma system? (2) What is the approach to achieve this task? (3) Do these systems work? Methods: We conducted a systematic review of relevant articles by searching electronic databases (PubMed, Embase, Cochrane library) using the following search terms: "trauma system", "polytrauma", "trauma networks", and "trauma registry". Of 2573 retrieved manuscripts, the authors made a personal selection of studies. A personal study selection from our experiences was added when their contribution to the topic was judged important. Results: Worldwide, similar tasks concerning trauma care have to be addressed. In most societies, traffic accidents and firearm-related injuries contribute to a high number of trauma victims. The German approach has been to decrease the number of accidents through injury prevention and to provide better care by establishing an emergency medical system. For in-hospital treatment, clinical care has constantly improved and a close interaction with members from the American Association for the Surgery of Trauma and the Orthopaedic Trauma Association has helped a great deal to achieve these improvements. The German healthcare system was developed as a powerful healthcare tool covering patients from injury to rehabilitation. In addition, trauma and injury research has been strengthened to deal with various questions of trauma care. Conclusions: Organized injury prevention programs and systematized professional patient care can address the issues associated with the global burden of trauma. These trauma systems require constant monitoring and improvement. © 2013 The Association of Bone and Joint Surgeons®.

Loading University of Aachen Medical Center collaborators
Loading University of Aachen Medical Center collaborators