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N Espinosa - One of the best experts on this subject based on the ideXlab platform.
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internal circular arc osteosynthesis of tibiotalocalcaneal arthrodesis
Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure "Bone Nail", in contrast to the "intramedullary Nail," which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment.
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Die innere Kreisbogen-Osteosynthese der tibio-talo-calcanealen Arthrodese
Der Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure “Bone Nail”, in contrast to the “intramedullary Nail,” which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment. Die tibio-talo-calcaneale Arthrodese erfährt heute eine steigende Popularität in der rekonstruktiven Chirurgie. Die genaue anatomische Orientierung des Rückfußes und eine funktionelle extrinsische Muskulatur des Rückfußes sind unentbehrlich für ein gutes Ergebnis. Die Fixation der Arthrodese ist ein mechanisches Problem. Gerade und geknickte Nägel sind anatomisch und mechanisch nicht optimal. Ein kreisbogenförmiger Knochennagel kann die Tibia, den Talus und den Calcaneus in anatomischem Alignement fest verbinden. Dabei handelt es sich um einen reinen „Knochennagel“, im Gegensatz zum „Marknagel“, der in einer vorbestehenden Öffnung bei Röhrenknochen geführt wird. Der Nagel wird durch eine kreisbogenförmige Aussparung geführt, die einen optimalen Formschluss zum Knochen ergibt. Ein entsprechendes Zielgerät erlaubt das genaue Fräsen der Aussparung, die den spongiösen Knochentrabekeln folgt. Elf Fälle wurden mit dem Instrumentarium operiert, mit den Indikationen von posttraumatischen Zuständen, kongenitalen Fehlstellungen, rheumatischer Polyarthritis und diabetischer Charcot-Arthropathie. Die gewünschte Einstellung des Alignements wird durch die Nageleinführung nicht beeinflusst. Die Fixation ergibt eine primäre Stabilität, mit dem Ziel einer frühzeitigen funktionellen Behandlung.
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Die innere Kreisbogen-Osteosynthese der tibio-talo-calcanealen Arthrodese@@@Internal circular arc osteosynthesis of tibiotalocalcaneal arthrodesis
Der Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure "Bone Nail", in contrast to the "intramedullary Nail," which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment.
Jalil Nourisa Ghadir Shaygan Gholamreza Rouhi - One of the best experts on this subject based on the ideXlab platform.
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Can we improve shear stability of intramedullary Nail for the fixation of distal tibial fractures
Journal of Biomimetics Biomaterials and Tissue Engineering, 2015Co-Authors: Jalil Nourisa Ghadir Shaygan Gholamreza RouhiAbstract:P for malalignment is the main disadvantage of IM Nailing, which can occur mainly as a result of reduced Bone-implant contact at the distal quarter and high shear interfragmentary movements (IFM). The goal of this study was to evaluate the performance of a new designed IM Nailing system in which an extra screw could be inserted right above the fracture gap. For this purpose, a three-dimensional finite element model of tibia-Nail system was constructed by considering a 3mm transverse gap at the distal quarter. Physiological boundary conditions were applied, and three different materials, i.e. stainless steel, titanium, and carbon/ epoxy, were assumed for the IM Nail. The von Mises stress, interfragmentary movements, and the specific production of different tissue phenotypes were obtained to make a comparison among different Bone-Nail constructs. Results of this study showed that inserting an extra screw above the fracture gap can cause a dramatic reduction in the shear IFM. However, since axial IFM mainly occurred as a result of bony fragments’ tilting, insertion of extra screw also restricted axial movements. Thus, in order to preserve stimulatory axial micromotion, the proposed design is recommended when an IM Nail with a low young modulus, such carbon/ epoxy, is used. The finite element model was validated with the results of in vitro tests on cadaver.
Karsten Schwieger - One of the best experts on this subject based on the ideXlab platform.
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Angle stable interlocking screws improve construct stability of intramedullary Nailing of distal tibia fractures: A biomechanical study
Injury, 2009Co-Authors: Joachim Horn, Boyko Gueorguiev, B. Linke, Dankward Höntzsch, Karsten SchwiegerAbstract:Introduction: Intramedullary Nailing is the treatment of choice for most displaced tibial shaft fractures. The ability to maintain a mechanically stable fixation becomes more difficult the further the fracture extends distally or proximally or when unreamed tibial Nails are used. We assumed that a new angular stable locking option would provide improved stability and reduced interfragmentary movements in a distal tibia in vitro fracture model. Materials and methods: Left and right Bones of 8 pairs of human cadaveric tibiae were randomly assigned to either a group with conventional locked or a group with angular stable locked intramedullary Nails. Nails of 10-mm-diameter were used after reaming up to 11 mm. A transverse distal osteotomy was performed and the specimens were tested mechanically under eccentric axial load. A video optical measurement system was used to determine the angular displacement of the osteotomy gap during loading. Results: Construct stiffness, maximum load of the Bone-Nail construct and gap angle at 0.5 kN load were measured. The group with the angular stable locking option showed significantly higher stiffness values and reduced fracture gap motion compared to the group with conventional locked Nails. Discussion: A new angular stable locking option of intramedullary Nails provides higher stability in terms of construct stiffness and reduced interfragmentary movements in a distal tibia in vitro fracture model.
Kaj Klaue - One of the best experts on this subject based on the ideXlab platform.
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internal circular arc osteosynthesis of tibiotalocalcaneal arthrodesis
Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure "Bone Nail", in contrast to the "intramedullary Nail," which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment.
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Die innere Kreisbogen-Osteosynthese der tibio-talo-calcanealen Arthrodese
Der Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure “Bone Nail”, in contrast to the “intramedullary Nail,” which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment. Die tibio-talo-calcaneale Arthrodese erfährt heute eine steigende Popularität in der rekonstruktiven Chirurgie. Die genaue anatomische Orientierung des Rückfußes und eine funktionelle extrinsische Muskulatur des Rückfußes sind unentbehrlich für ein gutes Ergebnis. Die Fixation der Arthrodese ist ein mechanisches Problem. Gerade und geknickte Nägel sind anatomisch und mechanisch nicht optimal. Ein kreisbogenförmiger Knochennagel kann die Tibia, den Talus und den Calcaneus in anatomischem Alignement fest verbinden. Dabei handelt es sich um einen reinen „Knochennagel“, im Gegensatz zum „Marknagel“, der in einer vorbestehenden Öffnung bei Röhrenknochen geführt wird. Der Nagel wird durch eine kreisbogenförmige Aussparung geführt, die einen optimalen Formschluss zum Knochen ergibt. Ein entsprechendes Zielgerät erlaubt das genaue Fräsen der Aussparung, die den spongiösen Knochentrabekeln folgt. Elf Fälle wurden mit dem Instrumentarium operiert, mit den Indikationen von posttraumatischen Zuständen, kongenitalen Fehlstellungen, rheumatischer Polyarthritis und diabetischer Charcot-Arthropathie. Die gewünschte Einstellung des Alignements wird durch die Nageleinführung nicht beeinflusst. Die Fixation ergibt eine primäre Stabilität, mit dem Ziel einer frühzeitigen funktionellen Behandlung.
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Die innere Kreisbogen-Osteosynthese der tibio-talo-calcanealen Arthrodese@@@Internal circular arc osteosynthesis of tibiotalocalcaneal arthrodesis
Der Unfallchirurg, 2016Co-Authors: Kaj Klaue, H Zwipp, Thomas Mittlmeier, N EspinosaAbstract:Tibiotalocalcaneal arthrodesis has recently become more popular as a form of reconstructive surgery. The precise anatomical orientation and the functional extrinsic musculature of the hindfoot are essential for a satisfactory result. Fixation of the arthrodesis is a mechanical problem. Straight and angulated Nails are not anatomically or mechanically ideal. A circular arc Nail can fix the tibia, the talus and the calcaneus in anatomical alignment. This is a pure "Bone Nail", in contrast to the "intramedullary Nail," which is driven through an existing opening in long Bones. The Nail is driven through a circular arc-shaped opening in the Bone, which results in optimal form-fit between Nail and Bone. A corresponding aiming device permits the precise shaping of the Bone tunnel, which follows the orientation of the Bone trabeculae. The instrumentation was applied in 11 cases, with the following indications: post-traumatic conditions, congenital deformities, chronic polyarthritis and diabetic Charcot arthropathy. The desired alignment of the hindfoot is not affected while the Nail is being introduced. The fixation achieves primary stability thus allowing for early functional treatment.
Harald Tscherne - One of the best experts on this subject based on the ideXlab platform.
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Recurrent rotational deformity of the femur after static locking of intramedullary Nails
The Journal of bone and joint surgery. British volume, 1997Co-Authors: Christian Krettek, Theodore Miclau, Michael Blauth, Ronald W. Lindsey, Christian Donow, Harald TscherneAbstract:Rotational deformity following intramedullary Nailing may cause symptoms and require surgical correction by osteotomy. Reamed, locked intramedullary Nailing may be performed, but concern about cortical blood supply and potential pulmonary dysfunction from reaming have led many surgeons to limit this and use smaller diameter Nails. Slotted Nails are commonly used but are less stiff in torsion than the newer unslotted Nails, particularly at the lower diameters. We report two cased of recurrent femoral rotational deformity after using statically interlocked slotted intramedullary Nails to correct existing femoral rotational deformities. These patients show that small diameter statically interlocked femoral Nails with diminished Bone-Nail contact must be stiff enough in rotation to avoid potential recurrence.