title: The Mechanical Functionality of the EXO-L Ankle Brace: Assessment With a 3-Dimensional Computed Tomography Stress Test.
abstract: BACKGROUND
  A new type of ankle brace (EXO-L) has recently been introduced. It is designed to limit the motion of most sprains without limiting other motions and to overcome problems such as skin irritation associated with taping or poor fit in the sports shoe.
  
  
  OBJECTIVE
  To evaluate the claimed functionality of the new ankle brace in limiting only the motion of combined inversion and plantar flexion.
  
  
  METHODS
  Controlled laboratory study.
  
  
  METHODS
  In 12 patients who received and used the new ankle brace, the mobility of the joints was measured with a highly accurate and objective in vivo 3-dimensional computed tomography (3D CT) stress test. Primary outcomes were the ranges of motion as expressed by helical axis rotations without and with the ankle brace between the following extreme positions: dorsiflexion to plantar flexion, and combined eversion and dorsiflexion to combined inversion and plantar flexion. Rotations were acquired for both talocrural and subtalar joints. A paired Student t test was performed to test the significance of the differences between the 2 conditions (P ≤ .05).
  
  
  RESULTS
  The use of the ankle brace significantly restricted the rotation of motion from combined eversion and dorsiflexion to combined inversion and plantar flexion in both the talocrural (P = .004) and subtalar joints (P < .001). No significant differences were found in both joints for the motion from dorsiflexion to plantar flexion.
  
  
  CONCLUSIONS
  The 3D CT stress test confirmed that under static and passive testing conditions, the new ankle brace limits the inversion-plantar flexion motion that is responsible for most ankle sprains without limiting plantar flexion or dorsiflexion.
  
  
  CONCLUSIONS
  This test demonstrated its use in the objective evaluation of braces.
authors.affiliation: Department of Anatomy, Embryology and Physiology, Academic Medical Center, Amsterdam, the Netherlands r.p.kleipool@amc.uva.nl.
authors.forename: Roeland P
authors.initials: RP
authors.lastname: Kleipool
authors.affiliation: Department of Biomechanical Engineering, Faculty of Mechanical, Materials and Maritime Engineering, Delft University of Technology, Delft, the Netherlands.
authors.forename: Jerry J
authors.initials: JJ
authors.lastname: Natenstedt
authors.affiliation: Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Geert J
authors.initials: GJ
authors.lastname: Streekstra
authors.affiliation: Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Johannes G G
authors.initials: JG
authors.lastname: Dobbe
authors.affiliation: Department of Orthopedic Surgery, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Rogier M
authors.initials: RM
authors.lastname: Gerards
authors.affiliation: Department of Orthopedic Surgery, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Leendert
authors.initials: L
authors.lastname: Blankevoort
authors.affiliation: Department of Orthopedic Surgery, Academic Medical Center, Amsterdam, the Netherlands.
authors.forename: Gabriëlle J M
authors.initials: GJ
authors.lastname: Tuijthof
mesh_terms: D000328:Adult; D016512:Ankle Injuries / Q000000981:diagnostic imaging / Q000503:physiopathology* / Q000628:therapy; D000843:Ankle Joint / Q000000981:diagnostic imaging / Q000502:physiology; D001696:Biomechanical Phenomena; D001915:Braces; D004867:Equipment Design; D005080:Exercise Test / Q000379:methods; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular / Q000502:physiology; D012399:Rotation; D012775:Shoes; D013380:Subtalar Joint / Q000000981:diagnostic imaging / Q000502:physiology; D013639:Tarsal Bones / Q000000981:diagnostic imaging / Q000503:physiopathology; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: ankle braces; inversion injury; prevention and rehabilitation; range of motion