title: A new device for assessing ankle dorsiflexion motion: reliability and validity.
abstract: METHODS
  Clinical measurement.
  
  
  OBJECTIVE
  To determine the validity and reliability of measures obtained using a custom-made device for assessing ankle dorsiflexion motion and stiffness.
  
  
  BACKGROUND
  Limited dorsiflexion has been implicated in the evolution of foot pain in a number of clinical populations. Assessment of ankle dorsiflexion range of motion (ROM) is, therefore, commonly performed as part of a foot and ankle examination. Conventional goniometric assessment methods have demonstrated limited intertester reliability, while alternative methods of measurements are generally more difficult to use. The Iowa ankle range of motion (IAROM) device was designed in an attempt to develop a simple, clinically relevant, and time- and cost-effective tool to measure ankle dorsiflexion range of motion and stiffness.
  
  
  METHODS
  Validity and intertester reliability of dorsiflexion range-of-motion measures using the IAROM device were assessed at 10, 15, 20, and 25 Nm of passively applied dorsiflexion torque, with both the knee extended and flexed approximately 20°. Stiffness (change in torque/change in dorsiflexion angle) values were determined using the angular change obtained between the 15- and 25-Nm torque levels. Convergent validity (n = 12) was assessed through comparison of ankle dorsiflexion angles measured simultaneously with the IAROM device and an optoelectronic motion analysis system. Intertester reliability (n = 17) was assessed by 2 testers who took measurements within the same day.
  
  
  RESULTS
  Validity testing demonstrated excellent agreement (intraclass correlation coefficient [ICC] values ranging from 0.95 to 0.98). Reliability testing demonstrated good to excellent intertester agreement (ICC values ranging from 0.90 to 0.95). The ICCs for ankle joint dorsiflexion stiffness were .71 and .85 for the knee in an extended and flexed position, respectively.
  
  
  CONCLUSIONS
  The IAROM device provides valid and reliable measurement of ankle dorsiflexion ROM. The IAROM device also allows calculation of stiffness by measuring ROM at multiple torque levels, although the reliability of the measurement is not optimal.
authors: Brooke Army Medical Center, Fort Sam Houston, TX, USA.
authors: Jason
authors: J
authors: Wilken
authors: Smita
authors: S
authors: Rao
authors: Miriam
authors: M
authors: Estin
authors: Charles L
authors: CL
authors: Saltzman
authors: H John
authors: HJ
authors: Yack
mesh_terms: D000843:Ankle Joint / Q000502:physiology*; D001696:Biomechanical Phenomena; D004867:Equipment Design; D005260:Female; D006801:Humans; D008297:Male; D016059:Range of Motion, Articular / Q000502:physiology*; D015203:Reproducibility of Results; D019415:Torque; D055815:Young Adult