title: A prospective randomised double-blind study of functional outcome and range of flexion following total knee replacement with the NexGen standard and high flexion components.
abstract: Modifications in the design of knee replacements have been proposed in order to maximise flexion. We performed a prospective double-blind randomised controlled trial to compare the functional outcome, including maximum knee flexion, in patients receiving either a standard or a high flexion version of the NexGen legacy posterior stabilised total knee replacement. A total of 56 patients, half of whom received each design, were assessed pre-operatively and at one year after operation using knee scores and analysis of range of movement using electrogoniometry. For both implant designs there was a significant improvement in the function component of the knee scores (p < 0.001) and the maximum range of flexion when walking on the level, ascending and descending a slope or stairs (all p < 0.001), squatting (p = 0.020) and stepping into a bath (p = 0.024). There was no significant difference in outcome, including the maximum knee flexion, between patients receiving the standard and high flexion designs of this implant.
authors.affiliation: Arthroplasty Service, Royal Infirmary of Edinburgh, Little France, Edinburgh EH16, 4SU, UK. richard.nutton@luht.scot.nhs.uk
authors.forename: R W
authors.initials: RW
authors.lastname: Nutton
authors.forename: M L
authors.initials: ML
authors.lastname: van der Linden
authors.forename: P J
authors.initials: PJ
authors.lastname: Rowe
authors.forename: P
authors.initials: P
authors.lastname: Gaston
authors.forename: F A
authors.initials: FA
authors.lastname: Wade
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019645:Arthroplasty, Replacement, Knee / Q000379:methods*; D016022:Case-Control Studies; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007719:Knee Joint / Q000503:physiopathology / Q000601:surgery*; D007720:Knee Prosthesis; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000503:physiopathology / Q000601:surgery*; D011446:Prospective Studies; D011474:Prosthesis Design; D016059:Range of Motion, Articular / Q000502:physiology*; D020127:Recovery of Function; D016896:Treatment Outcome