title: Anteroposterior glide versus rotating platform low contact stress (LCS) knee arthroplasty: a randomised controlled trial.
abstract: BACKGROUND
  Fifty thousand knee replacements are performed annually in the UK at an estimated cost of pound 150 million. Post-operative improvement depends on a number of factors including implant design and patient associated factors. To our knowledge there are no published study's comparing the results of AP glide and rotating platform designs of LCS knee arthroplasty. Therefore we feel that a study is required to investigate and compare the effects of two types of LCS total knee arthroplasty on joint proprioception and range of motion.
  
  
  METHODS
  Patients will be randomised to receive either a LCS AP glide or Rotating platform prosthesis. Clinical scores (Oxford knee score, American knee society score, EuroQol), range of motion and proprioception will be assessed prior to and at 3,6, 12 and 24 months after the operation. Proprioception will be assessed in terms of absolute error angle (mean difference between the target angle and the response angle). Knee angles will be measured in degrees using an electromagnetic tracking device, Polhemus 3Space Fastrak that detects positions of sensors placed on the test limb. Student's t-test will be used to compare the mean of two groups.
  
  
  CONCLUSIONS
  Evidence is lacking concerning the best prosthesis to use for patients undergoing total knee replacement. This pragmatic randomised trial will test the null hypothesis that anteroposterior glide LCS knee arthroplasty does not result in better post operative knee motion and proprioception as compared to rotating platform LCS knee.
authors.affiliation: University of Keele, Department of Trauma and Orthopaedics, Keele University Medical School, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK. g.walley@keele.ac.uk
authors.forename: Gayle
authors.initials: G
authors.lastname: Walley
authors.forename: Sandeep
authors.initials: S
authors.lastname: Datir
authors.forename: Murali
authors.initials: M
authors.lastname: Sayana
authors.forename: Aziz
authors.initials: A
authors.lastname: Rahmatalla
authors.forename: Ian
authors.initials: I
authors.lastname: Dos Remedios
authors.forename: Charles
authors.initials: C
authors.lastname: Wynn-Jones
authors.forename: Stephen
authors.initials: S
authors.lastname: Bridgman
authors.forename: Nicola
authors.initials: N
authors.lastname: Maffulli
mesh_terms: D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation* / Q000379:methods*; D001696:Biomechanical Phenomena / Q000379:methods; D006801:Humans; D007719:Knee Joint / Q000502:physiology / Q000601:surgery; D007720:Knee Prosthesis / Q000592:standards; D011434:Proprioception / Q000502:physiology; D011474:Prosthesis Design / Q000379:methods* / Q000592:standards; D016059:Range of Motion, Articular / Q000502:physiology; D012107:Research Design