Dörner, Jochen

[["dc.bibliographiccitation.firstpage","3"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","ACTA OF BIOENGINEERING AND BIOMECHANICS"],["dc.bibliographiccitation.lastpage","8"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Naegerl, Hans"],["dc.contributor.author","Hawellek, Thelonius"],["dc.contributor.author","Lehmann, Andrea"],["dc.contributor.author","Hubert, Jan"],["dc.contributor.author","Saptschak, Julia"],["dc.contributor.author","Doerner, Jochen"],["dc.contributor.author","Raab, Bjoern Werner"],["dc.contributor.author","Fanghaenel, Jochen"],["dc.contributor.author","Kubein-Meesenburg, Dietmar"],["dc.contributor.author","Wachowski, Martin Michael"],["dc.date.accessioned","2018-11-07T08:33:37Z"],["dc.date.available","2018-11-07T08:33:37Z"],["dc.date.issued","2009"],["dc.description.abstract","Spinal biomechanics is still known just fragmentary since the only description by angle-torque characteristics without simultaneous recording of migration of the instantaneous helical axis (IHA) is not sufficient. Time-dependent flexion/extension following a cyclic laterally directed torque was measured at all six degrees of freedom by a highly precise custom-made 6D apparatus. In order to enhance the localizing resolution of IHA migration as the function of the flexional/extensional angle, small ranges of motion (ROM) were used at several degrees of pre-extension. 4 L3/L4, 3 L4/L5 and 2 T2/T3 human segments were investigated. In extensional motion, wide dorsal IHA-migrations were measured in lumbar segments and correlated with the distinct asymmetric shapes of the characteristics in extensional motion. The respective increase of differential stiffness could mainly be traced back to the enlarging geometrical moment of inertia of the segments by the dorsally migrating IHA. Both thoracic segments showed a predominant IHA-migration in cranial/caudal direction. A simple model makes it evident that the opposite curvature morphology of lumbar and thoracic joint facets conditions the different directions of IHA migration."],["dc.identifier.isi","000278856100001"],["dc.identifier.pmid","20405809"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/17620"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wroclaw Univ Technology"],["dc.relation.issn","1509-409X"],["dc.title","Non-linearity of flexion-extension characteristics in spinal segments"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1739"],["dc.bibliographiccitation.issue","10"],["dc.bibliographiccitation.journal","Journal of Biomechanics"],["dc.bibliographiccitation.lastpage","1745"],["dc.bibliographiccitation.volume","46"],["dc.contributor.author","Wachowski, Martin Michael"],["dc.contributor.author","Wagner, Markus"],["dc.contributor.author","Weiland, Jan"],["dc.contributor.author","Doerner, Jochen"],["dc.contributor.author","Raab, Bjoern Werner"],["dc.contributor.author","Dathe, Henning"],["dc.contributor.author","Gezzi, Riccardo"],["dc.contributor.author","Kubein-Meesenburg, Dietmar"],["dc.contributor.author","Naegerl, Hans"],["dc.date.accessioned","2018-11-07T09:23:36Z"],["dc.date.available","2018-11-07T09:23:36Z"],["dc.date.issued","2013"],["dc.description.abstract","We analyze how kinematic properties of C3/C4-segments are modified after total disc arthroplasty (TDA) with PRESTIGE (R) and BRYAN (R) Cervical Discs. The measurements were focused on small ranges of axial rotation (<0.8 degrees) in order to investigate physiologic rotations, which frequently occur in vivo. Eight human segments were stimulated by triangularly varying, axially directed torque. By using a 6D-measuring device with high resolution the response of segmental motion was characterised by the instantaneous helical axis (IHA). Position, direction, and migration rate of the IHA were measured before and after TDA. External parameters: constant axially directed pre-load, constant flexional/extensional and lateral-flexional pre-torque. The applied axial torque and IHA-direction did not run parallel. The IHA-direction was found to be rotated backwards and largely independent of the rotational angle, amount of axial pre-load, size of pre-torque, and TDA. In the intact segments pre-flexion/extension hardly influenced IHA-positions. After TDA, IHA-position was shifted backwards significantly (BRYAN-TDA: approximate to 8 mm; PRESTIGE-TDA: approximate to 6 mm) and in some segments laterally as well. Furthermore it was significantly shifted ventrally by pre-flexion and dorsally by pre-extension. The rate of lateral IHA-migration increased significantly after BRYAN-TDA during rightward or leftward rotations. In conclusion after the TDA the IHA-positions shifted backwards with significant increase in variability of the IHA-positions after the BRYAN-TDA more than in PRESTIGE-TDA. The TDA-procedure altered the segment kinematics considerably. TDA causes additional translations of the vertebrae, which superimpose the kinematics of the adjacent levels. The occurrence of adjacent level disease (ALD) is not excluded after the TDA for kinematical reasons. (C) 2013 Elsevier Ltd. All rights reserved."],["dc.identifier.doi","10.1016/j.jbiomech.2013.03.027"],["dc.identifier.isi","000321422400020"],["dc.identifier.pmid","23659912"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/29619"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Elsevier Sci Ltd"],["dc.relation.issn","0021-9290"],["dc.title","Does total disc arthroplasty in C3/C4-segments change the kinematic features of axial rotation?"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","39"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","ACTA OF BIOENGINEERING AND BIOMECHANICS"],["dc.bibliographiccitation.lastpage","47"],["dc.bibliographiccitation.volume","12"],["dc.contributor.author","Wachowski, Martin Michael"],["dc.contributor.author","Hawellek, Thelonius"],["dc.contributor.author","Hubert, Jan"],["dc.contributor.author","Lehmann, Andrea"],["dc.contributor.author","Mansour, Michael"],["dc.contributor.author","Dumont, Clemens"],["dc.contributor.author","Doerner, Jochen"],["dc.contributor.author","Raab, Bjoern Werner"],["dc.contributor.author","Kubein-Meesenburg, Dietmar"],["dc.contributor.author","Naegerl, Hans"],["dc.date.accessioned","2018-11-07T08:46:51Z"],["dc.date.available","2018-11-07T08:46:51Z"],["dc.date.issued","2010"],["dc.description.abstract","The biomechanical role of the zygapophysial joints was investigated for axial rotations of lumbar segments by recording the positions of the instantaneous helical axis (IHA) against the axial rotational angle and by relating these IHA-positions to anatomical landmarks. Cyclically varying pure axial moments were applied to 3 L1/L2, 7 L3/L4 and 3 L4/L5 segments. There were 800 segment positions per cycle taken by a custom-made high precision 3D-position measuring system. In intact segments IHA-migration reached from one zygapophysial joint to the other IHA-paths came up to 10-60 mm within small angular intervals (+/- 1 deg). After removing the right joints, IHA-migration remained comparable with that of intact segments only for segment positions rotated to the right. Rotation to the left, however, approximately yielded stationary IHA-positions as found after resection of both joints. Hence, IHA-migration is determined by the joints already for small rotational angles. Each type of segment showed a typical pattern of IHA-migration."],["dc.identifier.isi","000288699300006"],["dc.identifier.pmid","21361255"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/20799"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.publisher","Wroclaw Univ Technology"],["dc.relation.issn","1509-409X"],["dc.title","Migration of the instantaneous axis of motion during axial rotation in lumbar segments and role of the zygapophysial joints"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.status","published"],["dspace.entity.type","Publication"]]