title: Outcomes before and after total knee arthroplasty compared to healthy adults.
abstract: METHODS
  Prospective cohort study.
  
  
  OBJECTIVE
  To measure changes in muscle strength, range of motion, and function from 2 weeks before to 6 months after total knee arthroplasty (TKA) and compare outcomes with data from a control group consisting of healthy adults.
  
  
  BACKGROUND
  Total knee arthroplasty successfully alleviates pain from knee osteoarthritis, but deficits in function can persist long term. How impairments and functional limitations change over the first 6 months after TKA, compared to data from healthy adults, has not been well reported in the literature.
  
  
  METHODS
  Twenty-four patients who underwent a primary unilateral TKA were compared to healthy adults (n = 17). All patients participated in a standardized rehabilitation program following surgery. Isometric quadriceps torque was assessed using an electromechanical dynamometer. Range of motion was measured actively and passively. Functional performance was assessed using the stair-climbing test, timed up-and-go test, 6-minute walk test, and single-limb stance time. Patients underwent testing at 2 weeks preoperatively and at 1, 3, and 6 months postoperatively.
  
  
  RESULTS
  Compared to healthy older adults, patients performed significantly worse at all times for all measures (P<.05), except for single-limb stance time at 6 months (P>.05). One month postoperatively, patients experienced significant losses from preoperative levels in all outcomes. Patients recovered to preoperative levels by 6 months postoperatively on all measures, except knee flexion range of motion, but still exhibited the same extent of limitation they did prior to surgery.
  
  
  CONCLUSIONS
  The persistent impairments and functional limitations 6 months after TKA with standard rehabilitation suggest that more intensive therapeutic approaches may be necessary to restore function of patients following TKA to the levels of healthy adults.
authors: University of Colorado, School of Medicine, Aurora, CO, USA.
authors: Michael J
authors: MJ
authors: Bade
authors: Wendy M
authors: WM
authors: Kohrt
authors: Jennifer E
authors: JE
authors: Stevens-Lapsley
mesh_terms: D000368:Aged; D019645:Arthroplasty, Replacement, Knee; D016022:Case-Control Studies; D005080:Exercise Test; D005260:Female; D006801:Humans; D007537:Isometric Contraction / Q000502:physiology; D007719:Knee Joint / Q000502:physiology; D008297:Male; D053581:Muscle Strength Dynamometer; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery; D017063:Outcome Assessment, Health Care; D011184:Postoperative Period; D057234:Preoperative Period; D011446:Prospective Studies; D016059:Range of Motion, Articular / Q000502:physiology