title: Uncemented HA-coated implant is the optimum fixation for TKA in the young patient.
abstract: Fixation of the tibial component in total knee arthroplasty in younger patients remains controversial. We evaluate the results of three different types of fixation of the Profix total knee arthroplasty in a randomized controlled trial of 97 consecutive knees (85 patients) with osteoarthrosis or inflammatory arthritis with 2-year followup of all patients. We randomized patients to three different types of fixation of the tibial component: cemented, uncemented (HA coated) with screws, or uncemented (HA coated) without screws. We performed clinical evaluations and radiostereometric analysis at 6 weeks, and 3, 6, 12 and 24 months postoperatively. The knees in the uncemented groups migrated more than those in the cemented group during the first 3 months, but at 2 years we observed no differences. The uncemented implants displayed all migration within the first 3 months. The cemented implants did not stabilize but had continuously increasing migration during the followup. Cementless implants without screws did not migrate more than implants with screws and displayed similar pattern of migration, indicating screws do not improve fixation. Uncemented fixation using hydroxyapatite-coated implants without screws seems to be the best solution for the younger patient.
  
  
  METHODS
  Therapeutic Level I. See the Guidelines for Authors for a complete description of levels of evidence.
authors.affiliation: Department of Orthopaedics, Umeå University Hospital, Sweden. kjell.g.nilsson@orthop.umu.se
authors.forename: Kjell G
authors.initials: KG
authors.lastname: Nilsson
authors.forename: Anders
authors.initials: A
authors.lastname: Henricson
authors.forename: Bo
authors.initials: B
authors.lastname: Norgren
authors.forename: Tore
authors.initials: T
authors.lastname: Dalén
mesh_terms: D000328:Adult; D000367:Age Factors; D019645:Arthroplasty, Replacement, Knee / Q000295:instrumentation*; D001863:Bone Screws; D020099:Coated Materials, Biocompatible; D017886:Durapatite; D005500:Follow-Up Studies; D006801:Humans; D007720:Knee Prosthesis; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000601:surgery*; D011474:Prosthesis Design; D016896:Treatment Outcome
chemical_list: D020099:Coated Materials, Biocompatible; D017886:Durapatite