title: [Ankle arthrometry for evaluation of the mechanical component in chronic ankle instability].
abstract: BACKGROUND
  Chronic ankle instability (CAI) is a term that is not well defined until now in spite of a large body of respective literature. Most frequently this umbrella term is used synonymously for functional ankle instability and the role of the mechanical component is not fully understood.
  
  
  METHODS
  In a cohort consisting of 15 patients suffering from CAI we preoperatively investigated the mechanical component using both stress radiographs and ankle arthrometry. The functional impact was measured with the FAAM-G (foot and ankle ability measure, German version). The results were compared with a respective group of 17 uninjured subjects.
  
  
  RESULTS
  Relevant differences were found between the patients and the uninjured groups in the mechanical (stiffness in the 40 - 60 N region of the load deformation curves and the ratio between stiffness in the 125 - 175 N and 40 - 60 N region) and functional analyses (FAAM-G), respectively (p < 0.001 - 0.040). There was no difference found between groups in the upper (125 - 175 N) region of the load deformation curves.
  
  
  CONCLUSIONS
  This article helps to clarify the role of the mechanical component in CAI. Patients suffering from both functional and mechanical ankle instability can be detected with the FAAM-G questionnaire and with different ankle stiffness parameters from ankle arthrometer stress testing. These measures differentiate CAI patients from uninjured persons with functionally and mechanically stable ankles. Therefore, these instruments can be recommended to diagnose and quantify the mechanical component in CAI.
authors: Sportmedizinisches Institut, 60528 Frankfurt am Main. lohrer@smi-frankfurt.de
authors: H
authors: H
authors: Lohrer
authors: T
authors: T
authors: Nauck
authors: D
authors: D
authors: Gehring
authors: A
authors: A
authors: Gollhofer
mesh_terms: D000293:Adolescent; D000328:Adult; D016512:Ankle Injuries / Q000175:diagnosis* / Q000503:physiopathology*; D053587:Arthrometry, Articular / Q000379:methods*; D001265:Athletic Injuries / Q000175:diagnosis* / Q000503:physiopathology*; D002908:Chronic Disease; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D005260:Female; D006801:Humans; D007593:Joint Instability / Q000175:diagnosis* / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D016059:Range of Motion, Articular; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods; D055815:Young Adult