title: Enhanced precision of ankle torque measure with an open-unit dynamometer mounted with a 3D force-torque sensor.
abstract: OBJECTIVE
  Many studies have focused on maximum torque exerted by ankle joint muscles during plantar flexion. While strength parameters are typically measured with isokinetic or isolated ankle dynamometers, these devices often present substantial limitations for the measurement of torque because they account for force in only 1 dimension (1D), and the device often constrains the body in a position that augments torque through counter movements. The purposes of this study were to determine the contribution of body position to ankle plantar-flexion torque and to assess the use of 1D and 3D torque sensors.
  
  
  METHODS
  A custom designed 'Booted, Open-Unit, Three dimension, Transportable, Ergometer' (B.O.T.T.E.) was used to quantify plantar flexion in two conditions: (1) when the participant was restrained within the unit (locked-unit) and (2) when the participant's position was independent of the ankle dynamometer (open-unit). Ten young males performed maximal voluntary isometric plantar-flexion contractions using the B.O.T.T.E. in open and locked-unit mechanical configurations.
  
  
  RESULTS
  The B.O.T.T.E. was reliable with ICC higher than 0.90, and CV lower than 7 %. The plantar-flexion maximal resultant torque was significantly higher in the locked-unit compared with open-unit configuration (P < 0.001; +61 to +157 %) due to the addition of forces from the body being constrained within the testing device. A 1D compared with 3D torque sensor significantly underestimated the proper capacity of plantar-flexion torque production (P < 0.001; -37 to -60 %).
  
  
  CONCLUSIONS
  Assessment of plantar-flexion torque should be performed with an open-unit dynamometer mounted with a 3D sensor that is exclusive of accessory muscles but inclusive of all ankle joint movements.
authors.affiliation: Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Le Mont Houy, 59313, Valenciennes, Cedex 09, France.
authors.forename: A
authors.initials: A
authors.lastname: Toumi
authors.affiliation: Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Le Mont Houy, 59313, Valenciennes, Cedex 09, France.|Centre de Rééducation Fonctionnelle La Rougeville, Saint-Saulve, France.
authors.forename: S
authors.initials: S
authors.lastname: Leteneur
authors.affiliation: Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Le Mont Houy, 59313, Valenciennes, Cedex 09, France.
authors.forename: C
authors.initials: C
authors.lastname: Gillet
authors.affiliation: Centre d'Analyse d'Images et Performance Sportive, Château de Boivre, 86580, Vouneuil-Sous-Biard, France.
authors.forename: J-F
authors.initials: JF
authors.lastname: Debril
authors.affiliation: Centre Hospitalier de la Région de Saint-Omer, Helfaut, France.
authors.forename: N
authors.initials: N
authors.lastname: Decoufour
authors.affiliation: Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Le Mont Houy, 59313, Valenciennes, Cedex 09, France.
authors.forename: F
authors.initials: F
authors.lastname: Barbier
authors.affiliation: School of Health and Exercise Sciences, University of British Columbia Okanagan, 3333 University Way, Kelowna, BC, V1V1V7, Canada.
authors.forename: J M
authors.initials: JM
authors.lastname: Jakobi
authors.affiliation: Laboratoire d'Automatique, de Mécanique et d'Informatique industrielles et Humaines (LAMIH) - UMR CNRS 8201, Université de Valenciennes et du Hainaut-Cambrésis (UVHC), Le Mont Houy, 59313, Valenciennes, Cedex 09, France. emilie.simoneau@univ-valenciennes.fr.
authors.forename: Emilie
authors.initials: E
authors.lastname: Simoneau-Buessinger
mesh_terms: D000328:Adult; D000843:Ankle Joint / Q000502:physiology*; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology*; D008297:Male; D053580:Muscle Strength / Q000502:physiology; D053581:Muscle Strength Dynamometer; D018482:Muscle, Skeletal / Q000502:physiology*; D019415:Torque; D055815:Young Adult
keywords: Force; Isometric; Muscle; Plantar flexion; Torque