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Fabian Krause - One of the best experts on this subject based on the ideXlab platform.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Dynamic Biomechanic Cadaveric Study
Foot & Ankle Orthopaedics, 2020Co-Authors: Fabian Krause, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Andreas FoeselAbstract:Category: Ankle; Basic Sciences/Biologics; Trauma Introduction/Purpose: In isolated lateral malleolar fractures of the supination-external rotation (SER) type and competent medial stabilizers (type II and III), non-operative treatment has yielded excellent outcome. With complete rupture of the deltoid ligament (SER type IV) fracture instability increases substantially. The rationale for operative treatment of SER type IV fractures is based upon good clinical results and previous biomechanical studies. A significant reduction of the ankle contact area that however is caused by an artificially forced lateralization of the talus in the ankle mortise has been demonstrated. Presumed resultant elevated Joint contact stresses are thought to lead to ankle arthritis in the longterm. Methods: In 12 lower leg specimen SER type injuries were simulated by gradual bony and ligamentous destabilization of the ankle from lateral to medial according to the mechanism of injury as described by Lauge and Hansen. High-resolution Pressure sensors placed in the ankle Joint recorded tibio-talar Pressure changes at physiologic weightbearing (700N) in three positions (plantigrade, 10° dorsiflexion and 20° plantarflexion). Results: With increasing instability changes of the ankle kinematics were seen in SER II and III fractures with the same trend also in SER IV lesions. In the plantigrade position, the medial clear space (MCS) increased significantly from an average of 2.5+-0.4mm (no fracture) to 3.9+-1.1mm (SER type IV fracture). However, the corresponding peak Pressure increased only slightly from 2.6+- 0.5 mPa to 3.0+-1.4 mPa on average, and the contact area decreased slightly from 810+-42 mm2 to 735+-27mm2 on average representing a non-significant reduction of only 9% of the contact area (p=0.08) after the deep deltoid ligament was completely dissected.The comparison of the results in plantigrade and plantarflexed position revealed substantial differences for MCS, contact area and center of force. Conclusion: Under physiologic load SER type IV isolated lateral malleolar fracture with completely disrupted deep deltoid ligament led to a significant increase of the MCS, but neither to a significant decrease of the of the Joint contact area nor significant increase of peak Pressure. Clinical Relevance: The findings of this biomechanical study support the recently reported good clinical results of non-operative treatment of SER type II to IV fractures.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Biomechanical Study in an Unrestrained Cadaver Model.
Foot & ankle specialist, 2020Co-Authors: Andreas C Fösel, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Fabian KrauseAbstract:BackgroundPrevious biomechanical studies simulating supination–external rotation (SER) IV injuries revealed different alterations in contact area and peak Pressure. We investigated Joint reaction f...
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Ankle Joint Pressure changes in high tibial and distal femoral osteotomies: a cadaver study.
The bone & joint journal, 2017Co-Authors: Fabian Krause, Ivan Zderic, Boyko Gueorguiev, A. Barandun, Georg Klammer, Timo SchmidAbstract:Aims To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the Pressure characteristics of the ankle Joint.Materials and MethodsVarus and valgus malalignment of the kn...
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Ankle Joint Pressure changes in a pes cavovarus model: supramalleolar valgus osteotomy versus lateralizing calcaneal osteotomy.
Foot & ankle international, 2013Co-Authors: Timo Schmid, Martin Weber, Ivan Zderic, Boyko Gueorguiev, Sebastian Zurbriggen, Fabian KrauseAbstract:Background:A fixed cavovarus foot deformity can be associated with anteromedial ankle arthrosis due to elevated medial Joint contact stresses. Supramalleolar valgus osteotomies (SMOT) and lateralizing calcaneal osteotomies (LCOT) are commonly used to treat symptoms by redistributing Joint contact forces. In a cavovarus model, the effects of SMOT and LCOT on the lateralization of the center of force (COF) and reduction of the peak Pressure in the ankle Joint were compared.Methods:A previously published cavovarus model with fixed hindfoot varus was simulated in 10 cadaver specimens. Closing wedge supramalleolar valgus osteotomies 3 cm above the ankle Joint level (6 and 11 degrees) and lateral sliding calcaneal osteotomies (5 and 10 mm displacement) were analyzed at 300 N axial static load (half body weight). The COF migration and peak Pressure decrease in the ankle were recorded using high-resolution TekScan Pressure sensors.Results:A significant lateral COF shift was observed for each osteotomy: 2.1 mm for...
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Hindfoot Joint Pressure in Supination Sprains
The American journal of sports medicine, 2012Co-Authors: Fabian Krause, Markus Windolf, Stefanie Blatter, Dirk Waehnert, Martin WeberAbstract:Background: Hindfoot trauma including ankle and subtalar sprains may be followed by osteochondral lesions and persisting pain originating from posttraumatic arthritis.Hypothesis: “Acute severe” supination sprains and “mild supination sprains with increasing ligamentous incompetence” of the hindfoot lead to medial ankle and subtalar stress concentrations that may contribute to osteochondral lesions (OCLs) and subsequent arthritis.Study Design: Controlled laboratory study.Methods: “Acute severe” sprains and “mild sprains with increasing ligamentous incompetence” (consecutive anterior talofibular ligament [ATFL], calcaneofibular ligament [CFL], and lateral talocalcaneal ligament [LTCL] transections) were simulated in human lower leg specimens (7 different specimens for each condition). The effect on the migration of the center of force (COF) and on the tibiotalar and subtalar Pressures at 700-N (acute severe) and 150-N (mild sprain with increasing ligamentous incompetence) axial static and dynamic loads, res...
Ivan Zderic - One of the best experts on this subject based on the ideXlab platform.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Dynamic Biomechanic Cadaveric Study
Foot & Ankle Orthopaedics, 2020Co-Authors: Fabian Krause, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Andreas FoeselAbstract:Category: Ankle; Basic Sciences/Biologics; Trauma Introduction/Purpose: In isolated lateral malleolar fractures of the supination-external rotation (SER) type and competent medial stabilizers (type II and III), non-operative treatment has yielded excellent outcome. With complete rupture of the deltoid ligament (SER type IV) fracture instability increases substantially. The rationale for operative treatment of SER type IV fractures is based upon good clinical results and previous biomechanical studies. A significant reduction of the ankle contact area that however is caused by an artificially forced lateralization of the talus in the ankle mortise has been demonstrated. Presumed resultant elevated Joint contact stresses are thought to lead to ankle arthritis in the longterm. Methods: In 12 lower leg specimen SER type injuries were simulated by gradual bony and ligamentous destabilization of the ankle from lateral to medial according to the mechanism of injury as described by Lauge and Hansen. High-resolution Pressure sensors placed in the ankle Joint recorded tibio-talar Pressure changes at physiologic weightbearing (700N) in three positions (plantigrade, 10° dorsiflexion and 20° plantarflexion). Results: With increasing instability changes of the ankle kinematics were seen in SER II and III fractures with the same trend also in SER IV lesions. In the plantigrade position, the medial clear space (MCS) increased significantly from an average of 2.5+-0.4mm (no fracture) to 3.9+-1.1mm (SER type IV fracture). However, the corresponding peak Pressure increased only slightly from 2.6+- 0.5 mPa to 3.0+-1.4 mPa on average, and the contact area decreased slightly from 810+-42 mm2 to 735+-27mm2 on average representing a non-significant reduction of only 9% of the contact area (p=0.08) after the deep deltoid ligament was completely dissected.The comparison of the results in plantigrade and plantarflexed position revealed substantial differences for MCS, contact area and center of force. Conclusion: Under physiologic load SER type IV isolated lateral malleolar fracture with completely disrupted deep deltoid ligament led to a significant increase of the MCS, but neither to a significant decrease of the of the Joint contact area nor significant increase of peak Pressure. Clinical Relevance: The findings of this biomechanical study support the recently reported good clinical results of non-operative treatment of SER type II to IV fractures.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Biomechanical Study in an Unrestrained Cadaver Model.
Foot & ankle specialist, 2020Co-Authors: Andreas C Fösel, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Fabian KrauseAbstract:BackgroundPrevious biomechanical studies simulating supination–external rotation (SER) IV injuries revealed different alterations in contact area and peak Pressure. We investigated Joint reaction f...
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Ankle Joint Pressure changes in high tibial and distal femoral osteotomies: a cadaver study.
The bone & joint journal, 2017Co-Authors: Fabian Krause, Ivan Zderic, Boyko Gueorguiev, A. Barandun, Georg Klammer, Timo SchmidAbstract:Aims To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the Pressure characteristics of the ankle Joint.Materials and MethodsVarus and valgus malalignment of the kn...
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Assessment of ankle and hindfoot stability and Joint Pressures using a human cadaveric model of a large lateral talar process excision: a biomechanical study.
Medicine, 2015Co-Authors: Andrew Sands, Markus Windolf, Ivan Zderic, Charles White, Michael Blankstein, Dieter Wahl, Manuela Ernst, Jennifer E. Hagen, R. Geoff Richards, Karl StoffelAbstract:Lateral talar process fragment excision may be followed by hindfoot instability and altered biomechanics. There is controversy regarding the ideal fragment size for internal fixation versus excision and a concern that excision of a large fragment may lead to significant instability. The aim of this study was to assess the effect of a simulated large lateral talar process excision on ankle and subtalar Joint stability. A custom-made seesaw rig was designed to apply inversion/eversion stress loading on 7 fresh-frozen human cadaveric lower legs and investigate them in pre-excision, 5 cm3 and 10 cm3 lateral talar process fragment excision states. Anteroposterior radiographs were taken to assess ankle and subtalar Joint tilt and calculate angular change from neutral hindfoot alignment to 10-kg forced inversion/eversion. Ankle Joint Pressures and contact areas were measured under 30-kg axial load in neutral hindfoot alignment. In comparison to the pre-excision state, no significantly different mediolateral angular change was observed in the subtalar Joint after 5 and 10 cm3 lateral talar process fragment excision in inversion and eversion. With respect to the ankle Joint, 10-cm3 fragment excision produced significantly bigger inversion tibiotalar tilt compared with the pre-excision state, P = .04. No significant change of the ankle Joint Pressure and contact area was detected after 5 and 10-cm3 excision in comparison with the pre-excison state. An excision of up to 10 cm3 of the lateral talar process does not cause a significant instability at the level of the subtalar Joint but might be a destabilizing factor at the ankle Joint under inversion stress. The latter could be related to extensive soft tissue dissection required for resection.
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Ankle Joint Pressure changes in a pes cavovarus model: supramalleolar valgus osteotomy versus lateralizing calcaneal osteotomy.
Foot & ankle international, 2013Co-Authors: Timo Schmid, Martin Weber, Ivan Zderic, Boyko Gueorguiev, Sebastian Zurbriggen, Fabian KrauseAbstract:Background:A fixed cavovarus foot deformity can be associated with anteromedial ankle arthrosis due to elevated medial Joint contact stresses. Supramalleolar valgus osteotomies (SMOT) and lateralizing calcaneal osteotomies (LCOT) are commonly used to treat symptoms by redistributing Joint contact forces. In a cavovarus model, the effects of SMOT and LCOT on the lateralization of the center of force (COF) and reduction of the peak Pressure in the ankle Joint were compared.Methods:A previously published cavovarus model with fixed hindfoot varus was simulated in 10 cadaver specimens. Closing wedge supramalleolar valgus osteotomies 3 cm above the ankle Joint level (6 and 11 degrees) and lateral sliding calcaneal osteotomies (5 and 10 mm displacement) were analyzed at 300 N axial static load (half body weight). The COF migration and peak Pressure decrease in the ankle were recorded using high-resolution TekScan Pressure sensors.Results:A significant lateral COF shift was observed for each osteotomy: 2.1 mm for...
Martin Weber - One of the best experts on this subject based on the ideXlab platform.
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Ankle Joint Pressure changes in a pes cavovarus model: supramalleolar valgus osteotomy versus lateralizing calcaneal osteotomy.
Foot & ankle international, 2013Co-Authors: Timo Schmid, Martin Weber, Ivan Zderic, Boyko Gueorguiev, Sebastian Zurbriggen, Fabian KrauseAbstract:Background:A fixed cavovarus foot deformity can be associated with anteromedial ankle arthrosis due to elevated medial Joint contact stresses. Supramalleolar valgus osteotomies (SMOT) and lateralizing calcaneal osteotomies (LCOT) are commonly used to treat symptoms by redistributing Joint contact forces. In a cavovarus model, the effects of SMOT and LCOT on the lateralization of the center of force (COF) and reduction of the peak Pressure in the ankle Joint were compared.Methods:A previously published cavovarus model with fixed hindfoot varus was simulated in 10 cadaver specimens. Closing wedge supramalleolar valgus osteotomies 3 cm above the ankle Joint level (6 and 11 degrees) and lateral sliding calcaneal osteotomies (5 and 10 mm displacement) were analyzed at 300 N axial static load (half body weight). The COF migration and peak Pressure decrease in the ankle were recorded using high-resolution TekScan Pressure sensors.Results:A significant lateral COF shift was observed for each osteotomy: 2.1 mm for...
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Hindfoot Joint Pressure in Supination Sprains
The American journal of sports medicine, 2012Co-Authors: Fabian Krause, Markus Windolf, Stefanie Blatter, Dirk Waehnert, Martin WeberAbstract:Background: Hindfoot trauma including ankle and subtalar sprains may be followed by osteochondral lesions and persisting pain originating from posttraumatic arthritis.Hypothesis: “Acute severe” supination sprains and “mild supination sprains with increasing ligamentous incompetence” of the hindfoot lead to medial ankle and subtalar stress concentrations that may contribute to osteochondral lesions (OCLs) and subsequent arthritis.Study Design: Controlled laboratory study.Methods: “Acute severe” sprains and “mild sprains with increasing ligamentous incompetence” (consecutive anterior talofibular ligament [ATFL], calcaneofibular ligament [CFL], and lateral talocalcaneal ligament [LTCL] transections) were simulated in human lower leg specimens (7 different specimens for each condition). The effect on the migration of the center of force (COF) and on the tibiotalar and subtalar Pressures at 700-N (acute severe) and 150-N (mild sprain with increasing ligamentous incompetence) axial static and dynamic loads, res...
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Ankle Joint Pressure changes in a pes cavovarus model after lateralizing calcaneal osteotomies.
Foot & ankle international, 2010Co-Authors: Fabian Krause, Markus Windolf, Karsten Schwieger, Dirk Waehnert, Damian Sutter, Martin WeberAbstract:Background: Tendon transfers and calcaneal osteotomies are commonly used to treat symptoms related to medial ankle arthrosis in fixed pes cavovarus. However, the relative effect of these osteotomies in terms of lateralizing the ground contact point of the hindfoot and redistributing ankle Joint contact stresses are unknown. Materials and Methods: Pes cavovarus with fixed hindfoot varus was simulated in eight cadaver specimens. The effect of three types of calcaneal osteotomies on the migration of the center of force and tibiotalar peak Pressure at 300 N axial static load (half-body weight) were recorded using Pressure sensors. Results: A significant lateral shift of the center of force was observed: 4.9 mm for the laterally closing Z-shaped osteotomy with additional lateralization of the tuberosity, 3.4 mm for the lateral sliding osteotomy of the calcaneal tuberosity, and 2.7 mm for the laterally closing Z-shaped osteotomy (all p < 0.001). A significant peak Pressure reduction was recorded: −0.53 MPa for ...
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Ankle Joint Pressure in pes cavovarus
The Journal of bone and joint surgery. British volume, 2007Co-Authors: Fabian Krause, Markus Windolf, Karsten Schwieger, Martin WeberAbstract:A cavovarus foot deformity was simulated in cadaver specimens by inserting metallic wedges of 15 degrees and 30 degrees dorsally into the first tarsometatarsal Joint. Sensors in the ankle Joint recorded static tibiotalar Pressure distribution at physiological load. The peak Pressure increased significantly from neutral alignment to the 30 degrees cavus deformity, and the centre of force migrated medially. The anterior migration of the centre of force was significant for both the 15 degrees (repeated measures analysis of variance (ANOVA), p = 0.021) and the 30 degrees (repeated measures ANOVA, p = 0.007) cavus deformity. Differences in ligament laxity did not influence the peak Pressure. These findings support the hypothesis that the cavovarus foot deformity causes an increase in anteromedial ankle Joint Pressure leading to anteromedial arthrosis in the long term, even in the absence of lateral hindfoot instability.
Boyko Gueorguiev - One of the best experts on this subject based on the ideXlab platform.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Dynamic Biomechanic Cadaveric Study
Foot & Ankle Orthopaedics, 2020Co-Authors: Fabian Krause, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Andreas FoeselAbstract:Category: Ankle; Basic Sciences/Biologics; Trauma Introduction/Purpose: In isolated lateral malleolar fractures of the supination-external rotation (SER) type and competent medial stabilizers (type II and III), non-operative treatment has yielded excellent outcome. With complete rupture of the deltoid ligament (SER type IV) fracture instability increases substantially. The rationale for operative treatment of SER type IV fractures is based upon good clinical results and previous biomechanical studies. A significant reduction of the ankle contact area that however is caused by an artificially forced lateralization of the talus in the ankle mortise has been demonstrated. Presumed resultant elevated Joint contact stresses are thought to lead to ankle arthritis in the longterm. Methods: In 12 lower leg specimen SER type injuries were simulated by gradual bony and ligamentous destabilization of the ankle from lateral to medial according to the mechanism of injury as described by Lauge and Hansen. High-resolution Pressure sensors placed in the ankle Joint recorded tibio-talar Pressure changes at physiologic weightbearing (700N) in three positions (plantigrade, 10° dorsiflexion and 20° plantarflexion). Results: With increasing instability changes of the ankle kinematics were seen in SER II and III fractures with the same trend also in SER IV lesions. In the plantigrade position, the medial clear space (MCS) increased significantly from an average of 2.5+-0.4mm (no fracture) to 3.9+-1.1mm (SER type IV fracture). However, the corresponding peak Pressure increased only slightly from 2.6+- 0.5 mPa to 3.0+-1.4 mPa on average, and the contact area decreased slightly from 810+-42 mm2 to 735+-27mm2 on average representing a non-significant reduction of only 9% of the contact area (p=0.08) after the deep deltoid ligament was completely dissected.The comparison of the results in plantigrade and plantarflexed position revealed substantial differences for MCS, contact area and center of force. Conclusion: Under physiologic load SER type IV isolated lateral malleolar fracture with completely disrupted deep deltoid ligament led to a significant increase of the MCS, but neither to a significant decrease of the of the Joint contact area nor significant increase of peak Pressure. Clinical Relevance: The findings of this biomechanical study support the recently reported good clinical results of non-operative treatment of SER type II to IV fractures.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Biomechanical Study in an Unrestrained Cadaver Model.
Foot & ankle specialist, 2020Co-Authors: Andreas C Fösel, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Fabian KrauseAbstract:BackgroundPrevious biomechanical studies simulating supination–external rotation (SER) IV injuries revealed different alterations in contact area and peak Pressure. We investigated Joint reaction f...
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Ankle Joint Pressure changes in high tibial and distal femoral osteotomies: a cadaver study.
The bone & joint journal, 2017Co-Authors: Fabian Krause, Ivan Zderic, Boyko Gueorguiev, A. Barandun, Georg Klammer, Timo SchmidAbstract:Aims To assess the effect of high tibial and distal femoral osteotomies (HTO and DFO) on the Pressure characteristics of the ankle Joint.Materials and MethodsVarus and valgus malalignment of the kn...
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Ankle Joint Pressure changes in a pes cavovarus model: supramalleolar valgus osteotomy versus lateralizing calcaneal osteotomy.
Foot & ankle international, 2013Co-Authors: Timo Schmid, Martin Weber, Ivan Zderic, Boyko Gueorguiev, Sebastian Zurbriggen, Fabian KrauseAbstract:Background:A fixed cavovarus foot deformity can be associated with anteromedial ankle arthrosis due to elevated medial Joint contact stresses. Supramalleolar valgus osteotomies (SMOT) and lateralizing calcaneal osteotomies (LCOT) are commonly used to treat symptoms by redistributing Joint contact forces. In a cavovarus model, the effects of SMOT and LCOT on the lateralization of the center of force (COF) and reduction of the peak Pressure in the ankle Joint were compared.Methods:A previously published cavovarus model with fixed hindfoot varus was simulated in 10 cadaver specimens. Closing wedge supramalleolar valgus osteotomies 3 cm above the ankle Joint level (6 and 11 degrees) and lateral sliding calcaneal osteotomies (5 and 10 mm displacement) were analyzed at 300 N axial static load (half body weight). The COF migration and peak Pressure decrease in the ankle were recorded using high-resolution TekScan Pressure sensors.Results:A significant lateral COF shift was observed for each osteotomy: 2.1 mm for...
Andreas C Fösel - One of the best experts on this subject based on the ideXlab platform.
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Ankle Joint Pressure in Supination-External Rotation Injuries: A Biomechanical Study in an Unrestrained Cadaver Model.
Foot & ankle specialist, 2020Co-Authors: Andreas C Fösel, Ivan Zderic, Angela Seidel, Boyko Gueorguiev, Marc C. Attinger, Fabian KrauseAbstract:BackgroundPrevious biomechanical studies simulating supination–external rotation (SER) IV injuries revealed different alterations in contact area and peak Pressure. We investigated Joint reaction f...
