title: Physical performance parameters during standing up in patients with unilateral and bilateral total knee arthroplasty.
abstract: OBJECTIVE
  The aim of this study was to compare quadriceps femoris muscle performance parameters of patients who underwent unilateral and bilateral total knee arthroplasty (TKA).
  
  
  METHODS
  The study included 80 patients. Thirty-five underwent unilateral primary TKA (35 females; mean age: 67.11 ± 3.97 years) and 45 underwent bilateral primary TKA (2 males, 43 females; mean age: 67.12 ± 7.32 years). Patients were evaluated in terms of performance parameters including stand-up time, rising index, standing postural sway velocity, and symmetries of body weight distribution on the extremities while standing up using a Balance Master® balance and performance instrument in the postoperative 6th and 12th month.
  
  
  RESULTS
  No significant difference was determined in body weight symmetry ratios between the operated and non-operated extremity in unilateral TKA patients in the 6th and 12th month sit-to-stand test (p>0.05) whereas there was a significant difference in bilateral TKA patients (p<0.05). There was no significant difference between unilateral and bilateral TKA patients in terms of time needed for standing up, rising index and gravity sway velocity at the postoperative 6th month and 12th month (p>0.05). Bilateral TKA patients stood up in a shorter time than unilateral TKA patients (p<0.05) although the degree of body sway was higher after standing up (p<0.05).
  
  
  CONCLUSIONS
  Bilateral TKA patients should be encouraged to focus on exercises with non-dominant limbs and to use them more while physiotherapy and rehabilitation programs including physical performance activities are planned.
authors.affiliation: Department of Physiotherapy and Rehabilitation, School of Health, İzmir University, İzmir, Turkey. serkan.bakirhan@izmir.edu.tr
authors.forename: Serkan
authors.initials: S
authors.lastname: Bakırhan
authors.forename: Salih
authors.initials: S
authors.lastname: Angın
authors.forename: Vasfi
authors.initials: V
authors.lastname: Karatosun
authors.forename: Bayram
authors.initials: B
authors.lastname: Ünver
authors.forename: Izge
authors.initials: I
authors.lastname: Günal
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee / Q000379:methods* / Q000534:rehabilitation*; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000000981:diagnostic imaging / Q000601:surgery; D010807:Physical Endurance / Q000502:physiology; D011184:Postoperative Period; D004856:Postural Balance / Q000502:physiology*; D011187:Posture / Q000502:physiology*; D011446:Prospective Studies; D052097:Quadriceps Muscle / Q000502:physiology*; D011859:Radiography; D016059:Range of Motion, Articular / Q000502:physiology*; D013647:Task Performance and Analysis; D013997:Time Factors; D016896:Treatment Outcome; D016474:Weight-Bearing / Q000502:physiology