title: Quantitative measures of sagittal plane head-neck control: a test-retest reliability study.
abstract: Determining the reliability of measurements used to quantify head-neck motor control is necessary before they can be used to study the effects of injury or treatment interventions. Thus, the purpose of this study was to determine the within- and between-day reliability of position tracking, position stabilization and force tracking tasks to quantify head-neck motor control. Ten asymptomatic subjects performed these tasks on two separate days. Position and force tracking tasks required subjects to track a pseudorandom square wave input signal by controlling their head-neck angular position (position tracking) or the magnitude of isometric force generated against a force sensor by the neck musculature (force tracking) in the sagittal plane. Position stabilization required subjects to maintain an upright head position while pseudorandom perturbations were applied to the upper body using a robotic platform. Within-day and between-day reliability of the frequency response curves were assessed using coefficients of multiple correlations (CMC). Root mean square error (RMSE) and mean bandpass signal energy, were computed for each task and between-day reliability was calculated using intra-class correlation coefficients (ICC). Within- and between-day CMCs for the position and force tracking tasks were all ≥0.96, while CMCs for position stabilization ranged from 0.72 to 0.82. ICCs for the position and force tracking tasks were all ≥0.93. For position stabilization, ICCs for RMSE and mean bandpass signal energy were 0.66 and 0.72, respectively. Measures of sagittal plane head-neck motor control using position tracking, position stabilization and force tracking tasks were demonstrated to be reliable.
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Osteopathic Surgical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA. Electronic address: popovi16@msu.edu.
authors.forename: John M
authors.initials: JM
authors.lastname: Popovich
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Osteopathic Surgical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA.
authors.forename: N Peter
authors.initials: NP
authors.lastname: Reeves
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Mechanical Engineering, College of Engineering, Michigan State University, East Lansing, MI, USA.
authors.forename: M Cody
authors.initials: MC
authors.lastname: Priess
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Osteopathic Surgical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA.
authors.forename: Jacek
authors.initials: J
authors.lastname: Cholewicki
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Mechanical Engineering, College of Engineering, Michigan State University, East Lansing, MI, USA; Department of Electrical and Computer Engineering, College of Engineering, Michigan State University, East Lansing, MI, USA.
authors.forename: Jongeun
authors.initials: J
authors.lastname: Choi
authors.affiliation: MSU Center for Orthopedic Research, College of Osteopathic Medicine, Michigan State University, Lansing, MI, USA; Department of Osteopathic Surgical Specialties, College of Osteopathic Medicine, Michigan State University, East Lansing, MI, USA; Department of Mechanical Engineering, College of Engineering, Michigan State University, East Lansing, MI, USA.
authors.forename: Clark J
authors.initials: CJ
authors.lastname: Radcliffe
mesh_terms: D000328:Adult; D005260:Female; D006257:Head / Q000502:physiology*; D006801:Humans; D008297:Male; D008954:Models, Biological; D009043:Motor Activity / Q000502:physiology; D009333:Neck / Q000502:physiology*; D009334:Neck Muscles / Q000502:physiology*; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D012371:Robotics
keywords: Cervical spine; Force tracking; Position stabilization; Position tracking; System identification