TY  - JOUR
A1  - Lohrer, Heinz
A1  - Nauck, Tanja
A1  - Gehring, Dominic
A1  - Wissler, Sabrina
A1  - Braag, Bela
A1  - Gollhofer, Albert
T1  - Differences between mechanically stable and unstable chronic ankle instability subgroups when examined by arthrometer and FAAM-G
T2  - Journal of orthopaedic surgery and research
N2  - Background: The objective measurement of the mechanical component and its role in chronic ankle instability is still a matter of scientific debate. We analyzed known group and diagnostic validity of our ankle arthrometer. Additionally, functional aspects of chronic ankle instability were evaluated in relation to anterior talar drawer.
Methods: By manual stress testing, 41 functionally unstable ankles were divided as mechanically stable (n = 15) or mechanically unstable (n = 26). Ankle laxity was quantified using an ankle arthrometer. Stiffness values from the load displacement curves were calculated between 40 and 60 N. Known group validity and eta2 were established by comparing manual and arthrometer testing results. Diagnostic validity for the ankle arthrometer was determined by a 2 × 2 contingency table. The functional ankle instability severity was quantified by the German version of the Foot and Ankle Ability Measure (FAAM-G). Stiffness (40–60 N) and FAAM-G values were correlated.
Results: Mechanically unstable ankles had lower 40–60 N stiffness values than mechanically stable ankles (p = 0.006 and <0.001). Eta for the relation between manual and arthrometer anterior talar drawer testing was 0.628. With 5.1 N/mm as cut-off value, accuracy, sensitivity, and specificity were 85%, 81%, and 93%, respectively. The correlation between individual 40–60 N arthrometer stiffness values and FAAM-G scores was r = 0.286 and 0.316 (p = 0.07 and 0.04).
Conclusions: In this investigation, the ankle arthrometer demonstrated a high diagnostic validity for the determination of mechanical ankle instability. A clear interaction between mechanical (ankle arthrometer) and functional (FAAM-G) measures could not be demonstrated.
KW  - Chronic ankle instability
KW  - Ankle arthrometer
KW  - FAAM
KW  - Functional ankle instability
KW  - Mechanical ankle instability
Y1  - 2015
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/37241
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-372415
SN  - 1749-799X
N1  - Copyright © Lohrer et al.; licensee BioMed Central. 2015. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.
VL  - 10
IS  - 32
PB  - BioMed Central
CY  - London
ER  -