title: The effects of task complexity on brake response time before and after primary right total knee arthroplasty.
abstract: OBJECTIVE
  To study the effects of an increase in task complexity on brake response time (BRT) in patients undergoing total knee arthroplasty (TKA).
  
  
  METHODS
  A prospective repeated-measures design was used. The measurements took place 1 day before and 10 and 30 days after surgery.
  
  
  METHODS
  Clinic.
  
  
  METHODS
  The data of patients (N=21) who were admitted for primary total arthroplasty of the right knee were pooled for analysis.
  
  
  METHODS
  On each measurement day patients performed 5 practice and 10 test trials for 2 tasks (1 simple, 1 complex) in a car simulator. Task complexity was increased by adding a second movement to the first task performed.
  
  
  METHODS
  BRT, reaction time (RT), and movement time were assessed.
  
  
  RESULTS
  An increase in task complexity increased BRT, RT, and movement time at all measurement times. Right TKA increased BRT by increasing movement time. Thirty days after surgery BRT was no longer increased compared with preoperative values in both tasks.
  
  
  CONCLUSIONS
  Task complexity consistently increased BRT and its components. The effects of task complexity remained constant throughout the 3 measurements. After right TKA, we suggest patients should be advised to wait 30 days after surgery before resuming driving.
authors.affiliation: Center for Research in Physiotherapy, Faculty of Human Movement Studies, Technical University of Lisbon, Lisbon, Portugal. carlos.marques@web.de
authors.forename: Carlos J
authors.initials: CJ
authors.lastname: Marques
authors.forename: Jan
authors.initials: J
authors.lastname: Cabri
authors.forename: João
authors.initials: J
authors.lastname: Barreiros
authors.forename: Ana I
authors.initials: AI
authors.lastname: Carita
authors.forename: Christian
authors.initials: C
authors.lastname: Friesecke
authors.forename: Jochen F
authors.initials: JF
authors.lastname: Loehr
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D019645:Arthroplasty, Replacement, Knee; D001334:Automobile Driving / Q000592:standards*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D011446:Prospective Studies; D011930:Reaction Time / Q000502:physiology*; D012449:Safety; D013647:Task Performance and Analysis; D013997:Time Factors