Sports Medicine

, Volume 44, Issue 12, pp 1777–1778 | Cite as

Author’s Reply to Liu et al.: “Important Issues Concerning Use of the Term ‘Copers’ in Chronic Ankle Instability Research”

  • Erik A. WikstromEmail author
  • Cathleen N. Brown
Letter to the Editor

We want to thank Liu and colleagues [1] for taking the time to continue the discussion around terminology and definitions for this unique population of individuals who have sprained their ankle but fail to develop the signs and symptoms associated with chronic ankle instability (CAI). The initial recommendation to use the term ‘coper’ was based in large part on our purpose: identifying trends in the literature to make recommendations that could help reduce between-study variability when examining this unique patient population, much like Delahunt et al. [2] did for those with CAI. Approximately 71 % (15/21) of published reports at the time our review was conducted used the term ‘coper’, while two additional studies used ‘ankle sprain copers’. Since then, three additional papers have been published in this area and all include the term ‘coper’ in some fashion (ankle sprain copers [3, 4], coper [5]). Currently, therefore, 83 % of the current literature includes the term ‘coper’ in some...


Injury Risk Ankle Sprain Lateral Ankle Ankle Injury Organismic Constraint 
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The authors have no competing interests to declare.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  1. 1.Department of KinesiologyUniversity of North Carolina at CharlotteCharlotteUSA
  2. 2.University of GeorgiaAthensUSA

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