Matthias Hölzl1,2, Winfried Neuhuber3, Olaf Ueberschär4,5, Axel Schleichardt5, Natalie Stamm6, Christoph Arens7, Andreas Biesdorf8, Ulrich Goessler6, Roland Hülse9. 1. Department of Otorhinolaryngology, Head and Neck Surgery, University Hospitals Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany. Matthias.hoelzl@hno.de. 2. ENT Centre of Traunstein, Maxplatz 5, 83278, Traunstein, Germany. Matthias.hoelzl@hno.de. 3. Institute of Anatomy and Cell Biology, Friedrich-Alexander-University of Erlangen-Nürnberg, Krankenhausstraße 9, 91054, Erlangen, Germany. 4. Department of Engineering and Industrial Design, Magdeburg-Stendal University of Applied Sciences, Breitscheidstraße 2, 39114, Magdeburg, Germany. 5. Department of Biomechanics, Institute for Applied Training Science, Marschnerstraße 29, 04109, Leipzig, Germany. 6. ENT Centre of Traunstein, Maxplatz 5, 83278, Traunstein, Germany. 7. Department of Otorhinolaryngology, Head and Neck Surgery, University Hospitals Otto-von-Guericke-University Magdeburg, Leipziger Str. 44, 39120, Magdeburg, Germany. 8. Siemens AG, Technology, Otto-Hahn-Ring 6, 81739, München, Germany. 9. Department of Medicine in Physiotherapy, Faculty of Therapeutic Sciences, Maria-Probst-Str. 3, 69123, Heidelberg, Germany.
Abstract
PURPOSE: It is still in question whether head oscillation damping during walking forms a part of the vestibular function. The anatomical pathway from the vestibular system to the neck muscles via the medial vestibulospinal tract (MVST) is well known but there is a lack of knowledge of the exact influence and modulation of each other in daily life activities. METHODS: (I) We fixed a head-neck unit of a human cadaver specimen in a steal frame to determine the required pitch-torque for a horizontal head position. The mean value of the acquired pitch-torque was 0.54 Nm. (II) On a motorized treadmill we acquired kinematic data of the head, the sternum and both feet by wireless 3D IMUs for seven asymptomatic volunteers. Subsequently three randomized task conditions were performed. Condition 1 was walking without any irritation. Condition 2 imitated a sacculus irritation using a standardized cVEMP signal. The third condition used an electric neck muscle-irritation (TENS). The data were analyzed by the simulation environment software OpenSim 4.0. RESULTS: 8 neck muscle pairs were identified. By performing three different conditions we observed some highly significant deviations of the neck muscle peak torques. Analysing Euler angles, we found during walking a LARP and RALP head pendulum, which also was strongly perturbated. CONCLUSION: Particularly the pitch-down head oscillation damping is the most challenging one for neck muscles, especially under biomechanical concerns. Mainly via MVST motor activity of neck muscles might be modulated by vestibular motor signals. Two simultaneous proprioceptor effects might optimize head oscillation damping. One might be a proprioceptive feedback loop to the vestibular nucleus. Another might trigger the cervicocollic reflex (CCR).
PURPOSE: It is still in question whether head oscillation damping during walking forms a part of the vestibular function. The anatomical pathway from the vestibular system to the neck muscles via the medial vestibulospinal tract (MVST) is well known but there is a lack of knowledge of the exact influence and modulation of each other in daily life activities. METHODS: (I) We fixed a head-neck unit of a human cadaver specimen in a steal frame to determine the required pitch-torque for a horizontal head position. The mean value of the acquired pitch-torque was 0.54 Nm. (II) On a motorized treadmill we acquired kinematic data of the head, the sternum and both feet by wireless 3D IMUs for seven asymptomatic volunteers. Subsequently three randomized task conditions were performed. Condition 1 was walking without any irritation. Condition 2 imitated a sacculus irritation using a standardized cVEMP signal. The third condition used an electric neck muscle-irritation (TENS). The data were analyzed by the simulation environment software OpenSim 4.0. RESULTS: 8 neck muscle pairs were identified. By performing three different conditions we observed some highly significant deviations of the neck muscle peak torques. Analysing Euler angles, we found during walking a LARP and RALP head pendulum, which also was strongly perturbated. CONCLUSION: Particularly the pitch-down head oscillation damping is the most challenging one for neck muscles, especially under biomechanical concerns. Mainly via MVST motor activity of neck muscles might be modulated by vestibular motor signals. Two simultaneous proprioceptor effects might optimize head oscillation damping. One might be a proprioceptive feedback loop to the vestibular nucleus. Another might trigger the cervicocollic reflex (CCR).
Authors: Scott L Delp; Frank C Anderson; Allison S Arnold; Peter Loan; Ayman Habib; Chand T John; Eran Guendelman; Darryl G Thelen Journal: IEEE Trans Biomed Eng Date: 2007-11 Impact factor: 4.538
Authors: Leigh A McGarvie; Hamish G MacDougall; G Michael Halmagyi; Ann M Burgess; Konrad P Weber; Ian S Curthoys Journal: Front Neurol Date: 2015-07-08 Impact factor: 4.003
Authors: Ajay Seth; Jennifer L Hicks; Thomas K Uchida; Ayman Habib; Christopher L Dembia; James J Dunne; Carmichael F Ong; Matthew S DeMers; Apoorva Rajagopal; Matthew Millard; Samuel R Hamner; Edith M Arnold; Jennifer R Yong; Shrinidhi K Lakshmikanth; Michael A Sherman; Joy P Ku; Scott L Delp Journal: PLoS Comput Biol Date: 2018-07-26 Impact factor: 4.475