170 results on '"Viehöfer, A."'
Search Results
152. Akustische und thermische Komfortuntersuchung innovativer Heizsysteme
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Pingel, Marc, primary, Backes, Damian, additional, Lichius, Thomas, additional, and Viehöfer, Jens, additional
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- 2015
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153. Der Verleger als Organisator Eugen Diederichs und die bürgerlichen Reformbewegungen der Jahrhundertwende
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Viehöfer, Erich, primary
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- 1988
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154. Testing service pipes in settling soil
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T Viehöfer and A Bezuijen
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Service (business) ,Waste management ,Settling ,Environmental science ,Civil engineering - Published
- 2006
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155. Effects of spontaneous breathing during airway pressure release ventilation on intestinal blood flow in experimental lung injury
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Hermann Wrigge, Rudolf Hering, Christian Putensen, Jörg Zinserling, Andreas Berg, Thomas Minor, Stefan Kreyer, and Andreas Viehöfer
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Artificial ventilation ,Swine ,medicine.medical_treatment ,Hemodynamics ,Lung injury ,Airway pressure release ventilation ,Heart Rate ,medicine ,Tidal Volume ,Animals ,business.industry ,Pulmonary Gas Exchange ,Blood flow ,Lung Injury ,Hypoxia (medical) ,Carbon Dioxide ,Respiration, Artificial ,Intestines ,Anesthesiology and Pain Medicine ,Respiratory failure ,Regional Blood Flow ,Anesthesia ,Respiratory Mechanics ,medicine.symptom ,Blood Gas Analysis ,business ,Perfusion - Abstract
Background In critical illness, the gut is susceptible to hypoperfusion and hypoxia. Positive-pressure ventilation can affect systemic hemodynamics and regional blood flow distribution, with potentially deleterious effects on the intestinal circulation. The authors hypothesized that spontaneous breathing (SB) with airway pressure release ventilation (APRV) provides better systemic and intestinal blood flow than APRV without SB. Methods Twelve pigs with oleic acid-induced lung injury received APRV with and without SB. When SB was abolished, either the tidal volume or the ventilator rate was increased to maintain pH and arterial carbon dioxide tension constant as compared to APRV with SB. Systemic hemodynamics were determined by double indicator dilution. Blood flow to the intestinal mucosa-submucosa and muscularis-serosa was measured using colored microspheres. Results Systemic blood flow increased during APRV with SB. During APRV with SB, mucosal-submucosal blood flow (ml. g-1. min-1) was 0.39 +/- 0.21 in the stomach, 0.76 +/- 0.35 in the duodenum, 0.71 +/- 0.35 in the jejunum, 0.71 +/- 0.59 in the ileum, and 0.63 +/- 0.21 in the colon. During APRV without SB and high tidal volumes, it decreased to 0.19 +/- 0.03 in the stomach, 0.42 +/- 0.21 in the duodenum, 0.37 +/- 0.10 in the jejunum, 0.3 +/- 0.14 in the ileum, and 0.41 +/- 0.14 in the colon (P < 0.001, respectively). During APRV without SB and low tidal volumes, the respective mucosal-submucosal blood flows decreased to 0.24 +/- 0.10 (P < 0.01), 0.54 +/- 0.21 (P < 0.05), 0.48 +/- 0.17 (P < 0.01), 0.43 +/- 0.21 (P < 0.01), and 0.50 +/- 0.17 (P < 0.001) as compared to APRV with SB. Muscularis-serosal perfusion decreased during full ventilatory support with high tidal volumes in comparison with APRV with SB. Conclusion Maintaining SB during APRV was associated with better systemic and intestinal blood flows. Improvements were more pronounced in the mucosal-submucosal layer.
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- 2003
156. Effects of Spontaneous Breathing during Airway Pressure Release Ventilation on Intestinal Blood Flow in Experimental Lung Injury
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Hering, Rudolf, primary, Viehöfer, Andreas, additional, Zinserling, Jörg, additional, Wrigge, Hermann, additional, Kreyer, Stefan, additional, Berg, Andreas, additional, Minor, Thomas, additional, and Putensen, Christian, additional
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- 2003
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157. The effect of neuraminidase on the 5-hydroxytryptamine uptake of human platelets
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Gielen, W. and Viehöfer, B.
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- 1974
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158. Comparing emergency medical service systems—A project of the European Emergency Data (EED) Project
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Matthias, Fischer, Johannes, Kamp, Luis, Garcia-Castrillo Riesgo, Iain, Robertson-Steel, Jerry, Overton, Alexandra, Ziemann, Thomas, Krafft, Andreas, Viehöfer, International Health, and RS: CAPHRI School for Public Health and Primary Care
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Tachycardia ,Emergency Medical Services ,medicine.medical_specialty ,Advance live support (ALS) ,Emergency Nursing ,Chest pain ,Pharmacotherapy ,Germany ,Heart rate ,Dyspnoea ,medicine ,Humans ,In patient ,Paramedic ,Prospective Studies ,Emergency medical service (EMS) system performance ,Prospective cohort study ,Intervention rate ,business.industry ,United Kingdom ,United States ,Emergency Medical Technicians ,Dyspnea ,Respiratory failure ,Emergency physician ,Spain ,Emergency ,Emergency medicine ,Workforce ,Emergency Medicine ,Cardiac chest pain ,medicine.symptom ,Out of hospital cardiac arrest (OHCA) ,Cardiology and Cardiovascular Medicine ,business ,Life Support Systems ,Out-of-Hospital Cardiac Arrest - Abstract
AimThe aim of this prospective study was the comparison of four emergency medical service (EMS) systems—emergency physician (EP) and paramedic (PM) based—and the impact of advanced live support (ALS) on patients status in preclinical care.MethodsThe EMS systems of Bonn (GER, EP), Cantabria (ESP, EP), Coventry (UK, PM) and Richmond (US, PM) were analysed in relation to quality of structure, process and performance when first diagnosis on scene was cardiac arrest (OHCA), chest pain or dyspnoea. Data were collected prospectively between 01.01.2001 and 31.12.2004 for at least 12 month.ResultsOver all 6277 patients were included in this study. The rate of drug therapy was highest in the EP-based systems Bonn and Cantabria. Pain relief was more effective in Bonn in patients with severe chest pain. In the group of patients with chest pain and tachycardia ≥120beats/min, the heart rate was reduced most effective by the EP-systems. In patients with dyspnoea and SpO2
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159. Implementation of mild therapeutic hypothermia therapy as standard care after successful CPR in a German general hospital
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Foedisch, M.J., Viehoefer, A., and Knuth, C.H.
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- 2008
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160. The effect of neuraminidase on the 5-hydroxytryptamine uptake of human platelets
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B. Viehöfer and W. Gielen
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Pharmacology ,Blood Platelets ,biology ,Chemistry ,5-hydroxytryptamine uptake ,Dopamine ,Neuraminidase ,Receptors, Cell Surface ,Cell Biology ,Molecular biology ,Cellular and Molecular Neuroscience ,biology.protein ,Molecular Medicine ,Humans ,Platelet ,Carbon Radioisotopes ,Molecular Biology - Abstract
Am 5-Hydroxytryptaminrezeptor der Thrombozyten ist die periphere Glykoprotein-Neuraminsaure nicht beteiligt. Der Verlust dieser peripheren Glykoprotein-Neuraminsaure fordert den Einstrom von 5-HT in die Thrombozyten. Der Rezeptor und der Transportmechanismus werden im Innern der Membran vermutet. Sie sind durch kurzfristige Neuraminidase-einwirkung nicht erreichbar.
- Published
- 1974
161. Der Verleger als Organisator Eugen Diederichs und die bürgerlichen Reformbewegungen der Jahrhundertwende
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Erich Viehöfer
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- 1988
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162. Planning tool for first metatarsal length in hallux valgus surgery
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Arnd F. Viehoefer, Philipp Fuernstahl, Stephan H. Wirth, Dominik C. Meyer, University of Zurich, and Viehoefer (Viehöfer), Arnd F
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medicine.medical_specialty ,First metatarsal bone ,medicine.medical_treatment ,610 Medicine & health ,Osteotomy ,03 medical and health sciences ,2732 Orthopedics and Sports Medicine ,0302 clinical medicine ,medicine ,Humans ,Orthopedics and Sports Medicine ,Hallux Valgus ,Podiatry ,Metatarsal Bones ,030203 arthritis & rheumatology ,First ray ,3613 Podiatry ,biology ,Foot ,business.industry ,First metatarsal ,Second metatarsal bone ,030229 sport sciences ,biology.organism_classification ,Surgery ,Radiography ,Valgus ,medicine.anatomical_structure ,10046 Balgrist University Hospital, Swiss Spinal Cord Injury Center ,Cadaveric spasm ,business - Abstract
The precise planning of metatarsal (MT) I length in hallux valgus surgery is important. However, currently no tool exists which allows the surgeon to reliably predict this parameter.30 virtual 3-dimensional hallux valgus surgeries were performed on varied deformation models based on cadaveric feet scans. The shortening of the first ray during distal metatarsal I osteotomy for different osteotomy angles were measured. An algebraic 2-dimensional calculation was done and compared to the results obtained from the 3-dimensional models.Inadvertent shortening of the first metatarsal bone can be as much as 8 mm depending on the amount of intermetatarsal angle (IMA) correction and osteotomy angle. Comparison of the 3 dimensional simulations and the 2 dimensional model resulted in a very strong correlation (R0.99 p0.00001). Based on our findings an anterior pointing osteotomy of approximately 10° is necessary to restore the length in distal metatarsal I hallux valgus surgery.A slight misdirection of the osteotomy plane in distal hallux valgus surgery may result in relevant unwanted alterations in first metatarsal bone length and triangulation by eye is insufficient in this complex geometrical situation without appropriate planning. The present study provides surgeons a practical tool to plan and control the change of first metatarsal length during hallux valgus procedure through exact orientation of the osteotomy angle. If no alteration of length is intended, it may be generalized that an anterior direction of the cut relative to the second metatarsal bone will preserve the length of the first metatarsal bone.
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- 2021
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163. Therapy for Non-Diabetic Foot Infections After Orthopedic Foot and Ankle Surgery: The Duration of Post-Debridement Antibiotic Treatment Does Not Alter Failure Risk.
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Scherer M, Soldevila-Boixader L, Yιldιz İ, Altorfer FCS, Furrer PR, Beeler S, Wirth SH, Viehöfer A, and Uçkay İ
- Abstract
Despite growing numbers of scientific publications on the optimal antibiotic treatment for diabetic foot infections, the data on the adult population with non-diabetic (postsurgical) foot infections is limited. Therefore, one of the largest single-center databases at the Balgrist University Hospital in Zurich, Switzerland, was established between January 2014 and August 2022. Using a case-control study design, we retrospectively investigated failures of combined surgical and antibiotic therapy for surgical site foot infections (SSIs). Overall, 17.4% of the episodes experienced therapeutic failures, particularly in patients with infected ankle prostheses. However, age, biological sex, pathogens, the duration of post-debridement antibiotic treatment, the number of surgical debridements, or the use of negative-pressure wound care altered the failure risk. In the multivariate logistic regression analyses, the duration of postsurgical antibiotic use was completely indifferent (as a continuous variable with an odds ratio of 1.0 and a 95% confidence interval ranging from 0.96 to 1.03) when stratified into inter-tertiary groups. Our findings suggest that shorter courses of systemic antibiotics may be appropriate in non-diabetic adults, supporting better antibiotic stewardship. Ongoing randomized controlled trials are under way to investigate which patients might safely receive shorter antibiotic treatments for surgical site infections following elective foot and ankle procedures.
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- 2024
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164. Bilateral External Torque CT Reliably Detects Syndesmotic Lesions in an Experimental Cadaveric Study.
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Beeler S, Ongini E, Hochreiter B, Sutter R, Viehöfer A, Wirth S, and Calek AK
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- Humans, Torque, Reproducibility of Results, Cadaver, Ankle Joint diagnostic imaging, Tomography, X-Ray Computed methods
- Abstract
Background: If tibiofibular syndesmotic injury is undetected, chronic instability may lead to persistent pain and osteoarthritis. So far, no reliable diagnostic method has been available. The primary objectives of this study were to determine whether defined lesions of the syndesmosis can be correlated with specific tibiofibular joint displacements caused by external rotational torque and to compare the performance of bilateral external torque computed tomography (BET-CT) and arthroscopy. Secondary objectives included an evaluation of the reliability of CT measurements and the suitability of the healthy contralateral ankle as a reference., Methods: Seven pairs of healthy, cadaveric lower legs were tested and assigned to 2 groups: (1) supination-external rotation (SER) and (2) pronation-external rotation (PER). In the intact state and after each surgical step, an ankle arthroscopy and 3 CT scans were performed. During the scans, the specimens were placed in an external torque device with 2.5, 5.0, and 7.5 Nm of torque applied., Results: The arthroscopic and CT parameters showed significant correlations in all pairwise comparisons. The receiver operating characteristic (ROC) curve analyses yielded the best prediction of syndesmotic instability with the anterior tibiofibular distance on CT, with a sensitivity of 84.1% and a specificity of 95.2% (area under the curve [AUC], 94.8%; 95% confidence interval [CI], 0.916 to 0.979; p < 0.0001) and with the middle tibiofibular distance on arthroscopy, with a sensitivity of 76.2% and specificity of 92.3% (AUC, 91.2%; 95% CI, 0.837 to 0.987; p < 0.0001). Higher torque amounts increased the rate of true-positive results., Conclusions: BET-CT reliably detects experimental syndesmotic rotational instability, compared with the healthy side, with greater sensitivity and similar specificity compared with the arthroscopic lateral hook test. Translation of these experimental findings to clinical practice remains to be established., Level of Evidence: Diagnostic Level III . See Instructions for Authors for a complete description of levels of evidence., Competing Interests: Disclosure: No external funding was received for this work. The Disclosure of Potential Conflicts of Interest forms are provided with the online version of the article ( http://links.lww.com/JBJS/H853 )., (Copyright © 2024 by The Journal of Bone and Joint Surgery, Incorporated.)
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- 2024
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165. Talocalcaneal Ligament Reconstruction Kinematic Simulation for Progressive Collapsing Foot Deformity.
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Mania S, Beeler S, Wirth S, and Viehöfer A
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- Humans, Ankle Joint surgery, Biomechanical Phenomena, Pilot Projects, Ligaments, Articular surgery, Talus surgery, Foot Deformities
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Background: In progressive collapsing foot deformity (PCFD), an internal and plantar rotation of the talus relative to the calcaneus may result in painful peritalar subluxation. Medial soft tissue procedures (eg, spring ligament repair) aim to correct the talar position via the navicular bone if bony correction alone is not sufficient. The effect of the medial soft tissue reconstruction on the talar reposition remains unclear. We hypothesized that a subtalar talocalcaneal ligament reconstruction might be favorable in PCFD to correct talar internal malposition directly. This pilot study aims to evaluate the anatomical feasibility and kinematic behavior of a subtalar ligament reconstruction in PCFD., Methods: Three-dimensional surface model from 10 healthy ankles were produced. A total of 1089 different potential ligament courses were evaluated in a standardized manner. A motion of inversion/eversion and talar internal/external in relation to the calcaneus were simulated and the ligament strain, expressed as a positive length variation, for each ligament was analyzed. The optimal combination for the ligament reconstruction with increased length in internal rotation of the talus, isometric kinematic behavior in inversion/eversion, and extraarticular insertion on talus and calcaneus was selected., Results: A laterodistal orientation of the talar insertion point in respect to the subtalar joint axis and laterodistal deviation of the calcaneal insertion point presents the highest ligament lengthening in internal talar rotation (+0.56 mm [3.8% of total length]) and presented a near-isometric performance in inversion/eversion (+0.01 to -0.01 mm [0.1% of total length])., Conclusion: This kinematic model shows that a ligament reconstruction in the subtalar space presents a pattern of length variation that may stabilize the internal talar rotation without impeding the physiological subtalar motion., Clinical Relevance: This study investigates the optimal location, feasibility, and kinematic behavior of a ligament reconstruction that could help stabilize peritalar subluxation in progressive collapsing foot deformity., [Formula: see text]., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article. ICMJE forms for all authors are available online.
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- 2024
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166. Risk Factors for Surgical Site Infections in Elective Orthopedic Foot and Ankle Surgery: The Role of Diabetes Mellitus.
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Soldevila-Boixader L, Viehöfer A, Wirth S, Waibel F, Yildiz I, Stock M, Jans P, and Uçkay I
- Abstract
Surgical site infection (SSI) after elective orthopedic foot and ankle surgery is uncommon and may be higher in selected patient groups. Our main aim was to investigate the risk factors for SSI in elective orthopedic foot surgery and the microbiological results of SSI in diabetic and non-diabetic patients, in a tertiary foot center between 2014 and 2022. Overall, 6138 elective surgeries were performed with an SSI risk of 1.88%. The main independent associations with SSI in a multivariate logistic regression analysis were an ASA score of 3-4 points, odds ratio (OR) 1.87 (95% confidence interval (CI) 1.20-2.90), internal, OR 2.33 (95% CI 1.56-3.49), and external material, OR 3.08 (95% CI 1.56-6.07), and more than two previous surgeries, OR 2.86 (95% CI 1.93-4.22). Diabetes mellitus showed an increased risk in the univariate analysis, OR 3.94 (95% CI 2.59-5.99), and in the group comparisons (three-fold risk). In the subgroup of diabetic foot patients, a pre-existing diabetic foot ulcer increased the risk for SSI, OR 2.99 (95% CI 1.21-7.41), compared to non-ulcered diabetic patients. In general, gram-positive cocci were the predominant pathogens in SSI. In contrast, polymicrobial infections with gram-negative bacilli were more common in contaminated foot surgeries. In the latter group, the perioperative antibiotic prophylaxis by second-generation cephalosporins did not cover 31% of future SSI pathogens. Additionally, selected groups of patients revealed differences in the microbiology of the SSI. Prospective studies are required to determine the importance of these findings for optimal perioperative antibiotic prophylactic measures.
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- 2023
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167. A novel approach for joint line restoration in revision total ankle arthroplasty based on the three-dimensional registration of the contralateral tibia and fibula.
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Hodel S, Calek AK, Cavalcanti N, Fucentese SF, Vlachopoulos L, Viehöfer A, and Wirth SH
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Purpose: The use of total ankle arthroplasty (TAA) is increasing over time, as so will the need for revision TAAs in the future. Restoration of the ankle joint line (JL) in revision TAA is often difficult due to severe bone loss. This study analyzed the accuracy of a three-dimensional (3D) registration of the contralateral tibia and fibula to restore the ankle joint line (JL) and reported side-to-side differences of anatomical landmarks., Methods: 3D triangular surface models of 96 paired lower legs underwent a surface registration algorithm for superimposition of the mirrored contralateral lower leg onto the original lower leg to approximate the original ankle JL using a proximal, middle and distal segment. Distances of the distal fibular tip, anterior and posterior medial colliculus to the JL were measured and absolute side-to-side differences reported. Anterior lateral distal tibial angle (ADTA) and lateral distal tibial angle (LDTA) were measured., Results: Mean JL approximation was most accurate for the distal segment (0.1 ± 1.4 mm (range: -3.4 to 2.8 mm)) and middle segment (0.1 ± 1.2 mm (range: -2.8 to 2.5 mm)) compared to the proximal segment (-0.2 ± 1.6 mm (range: -3.0 to 4.9 mm)) (p = 0.007). Distance of the distal fibular tip, the anterior, and posterior medial colliculus to the JL, ADTA and LDTA yielded no significant side-to-side differences (n.s.)., Conclusion: 3D registration of the contralateral tibia and fibula reliably approximated the original ankle JL. The contralateral distal fibular tip, anterior and posterior medial colliculi, ADTA and LDTA can be used reliably for the planning of revision TAA with small side-to-side differences reported., Level of Evidence: IV., (© 2023. The Author(s).)
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- 2023
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168. Isometric points in lateral ankle ligament reconstruction: A three-dimensional kinematic study.
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Mania S, Zindel C, Wirth S, and Viehöfer A
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- Humans, Cadaver, Ankle Joint diagnostic imaging, Ankle Joint surgery, Fibula surgery, Lateral Ligament, Ankle surgery, Calcaneus, Joint Instability surgery
- Abstract
Background: To optimize the biomechanical outcomes in lateral ankle ligament reconstruction, avoid stiffness or residual laxity, aiming for an isometric reconstruction of the anterior lateral talofibular ligament (ATFL) and the calcaneofibular ligament (CFL) is mandatory. However, the localization of the optimal ligament insertion remains challenging to assess intraoperatively., Method: Three-dimensional (3D) surface models from 10 healthy ankles were generated. 30 insertion points of the CFL were defined on the lateral side of the calcaneus each 10% of its total length in the dorsal-to-ventral and proximal-to-distal plane. 6 insertion points were defined at the ventral ridge of fibula from the malleolar tip and 5 insertions were defined along the lateral talar process. The ligament length variation of ATFL and CFL was assessed after a simulation of the flexion/extension around a simulated tibiotalar axis and inversion/eversion around a simulated subtalar axis in 36 different positions., Results: The isometric point of CFL on the calcaneus is located at about 60% along the dorsal-to-ventral and between 60% and 70% along the proximal-to-distal plane. From maximal extension to flexion, these points present respectively a length variation of - 0.8 to - 1.1 mm (p = 0.46) and - 1.1 to - 0.8 mm (p = 0.56). A fibular insertion at 5 mm proximal to the malleolar tip present a length variation ranging from - 0.1-1 mm (p < 0.001) for ATFL and from - 0.7-0.5 mm (p < 0.001) for CFL. A talar insertion point of the ATFL located 5 mm proximal to the subtalar joint present the lowest variation, ranging from - 1.1-0.7 mm (p < 0.001), however an insertion at 20- or 25-mm present isometry (+0.1 to +0.9 mm p = 0.1, and +0.4 to +0.4 mm p = 1 respectively) if the fibular insertion is located at 5 mm proximal to the malleolar tip., Conclusion: This study provides anatomical references which are reproducible in daily practice. These insertion points allow to achieve a stable reconstruction while maintaining a tension-free mobilization of the ankle., Competing Interests: Declaration of Competing Interest Each author certifies that there are no funding or commercial associations (consultancies, stock ownership, equity interest, patent/licensing arrangements, etc.) that might pose a conflict of interest in connection with the submitted article related to the author or any immediate family members., (Copyright © 2022 The Authors. Published by Elsevier Ltd.. All rights reserved.)
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- 2022
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169. Talus morphology differs between flatfeet and controls, but its variety has no influence on extent of surgical deformity correction.
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Flury A, Hasler J, Beeler S, Imhoff FB, Wirth SH, and Viehöfer A
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- Foot, Humans, Osteotomy methods, Calcaneus diagnostic imaging, Calcaneus surgery, Flatfoot diagnostic imaging, Flatfoot etiology, Flatfoot surgery, Talus diagnostic imaging, Talus surgery
- Abstract
Background: Progressive collapsing foot deformity (PCFD) is a complex 3-dimensional (3-D) deformity with varying degrees of hindfoot valgus, forefoot abduction, and midfoot varus. The first aim of this study was to perform a 3-D analysis of the talus morphology between symptomatic PCFD patients that underwent operative flatfoot correction and controls. The second aim was to investigate if there is an impact of individual talus morphology on the success of operative flatfoot correction., Methods: We reviewed all patients that underwent lateral calcaneal lengthening for correction of PCFD between 2008 and 2018 at our clinic. Radiographic flatfoot parameters on preoperative and postoperative radiographs were assessed. Additionally, 3-D surface models of the tali were generated using computed tomography (CT) data. The talus morphology of 44 flatfeet was compared to 3-D models of 50 controls without foot or ankle pain of any kind., Results: Groups were comparable regarding demographics. Talus morphology differed significantly between PCFD and controls in multiple aspects. There was a 2.6° increased plantar flexion (22.3° versus 26°; p = 0.02) and medial deviation (31.7° and 33.5°; p = 0.04) of the talar head in relation to the body in PCFD patients compared to controls. Moreover, PCFD were characterized by an increased valgus (difference of 4.6°; p = 0.01) alignment of the subtalar joint. Satisfactory correction was achieved in all cases, with an improvement of the talometatarsal-angle and the talonavicular uncoverage angle of 5.6° ± 9.7 (p = 0.02) and 9.9° ± 16.3 (p = 0.001), respectively. No statistically significant correlation was found between talus morphology and the correction achieved or loss of correction one year postoperatively., Conclusion: The different morphological features mentioned above might be contributing or risk factors for progression to PCFD. However, despite the variety of talar morphology, which is different compared to controls, the surgical outcome of calcaneal lengthening osteotomy was not affected., Level of Evidence: III., (© 2021. The Author(s).)
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- 2022
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170. Restoration of the patient-specific anatomy of the distal fibula based on a novel three-dimensional contralateral registration method.
- Author
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Calek AK, Hodel S, Hochreiter B, Viehöfer A, Fucentese S, Wirth S, and Vlachopoulos L
- Abstract
Purpose: Posttraumatic fibular malunion alters ankle joint biomechanics and may lead to pain, stiffness, and premature osteoarthritis. The accurate restoration is key for success of reconstructive surgeries. The aim of this study was to analyze the accuracy of a novel three-dimensional (3D) registration algorithm using different segments of the contralateral anatomy to restore the distal fibula., Methods: Triangular 3D surface models were reconstructed from computed tomographic data of 96 paired lower legs. Four segments were defined: 25% tibia, 50% tibia, 75% fibula, and 75% fibula and tibia. A surface registration algorithm was used to superimpose the mirrored contralateral model on the original model. The accuracy of distal fibula restoration was measured., Results: The median rotation error, 3D distance (Euclidean distance), and 3D angle (Euler's angle) using the distal 25% tibia segment for the registration were 0.8° (- 1.7-4.8), 2.1 mm (1.4-2.9), and 2.9° (1.9-5.4), respectively. The restoration showed the highest errors using the 75% fibula segment (rotation error 3.2° (0.1-8.3); Euclidean distance 4.2 mm (3.1-5.8); Euler's angle 5.8° (3.4-9.2)). The translation error did not differ significantly between segments., Conclusion: 3D registration of the contralateral tibia and fibula reliably approximated the premorbid anatomy of the distal fibula. Registration of the 25% distal tibia, including distinct anatomical landmarks of the fibular notch and malleolar colliculi, restored the anatomy with increasing accuracy, minimizing both rotational and translational errors. This new method of evaluating malreductions could reduce morbidity in patients with ankle fractures., Level of Evidence: IV., (© 2022. The Author(s).)
- Published
- 2022
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