title: Stepwise introduction of a bone-conserving osseointegrated hip arthroplasty using RSA and a randomized study: I. Preliminary investigations--52 patients followed for 3 years.
abstract: BACKGROUND
  We developed a total hip system using osseointegration guidelines, a metaphyseal-loading proximal femoral replacement in the retained neck and a dual-geometry titanium shell in the acetabulum.
  
  
  METHODS
  A randomized controlled clinical trial was undertaken in 52 patients (53 hips), using the cemented Spectron stem and cementless Harris-Galante II cup as control implants (24 patients in experimental group, 29 control patients). Clinical measures of Harris Hip Score (HHS), pain score and radiostereometric analysis (RSA) at regular intervals for up to three years were used to monitor progress.
  
  
  RESULTS
  No statistically significant differences were found in HHS and pain score; the stability of the cementless experimental implant was also comparable to that of the cemented controls by RSA. 3 revisions were required for migration in the experimental group and 1 was required for component dislocation in the control group.
  
  
  CONCLUSIONS
  Our findings indicate the practicality of osseointegration of titanium implants, but suggest that current performance is inadequate for clinical introduction. However, the stable fixation achieved in the retained neck in the majority of patients is indicative of osseointegration. This finding will encourage technical and design improvements for enhancement of clinical osseointegration and should also encourage further study. Periprosthetic osteolysis might be avoided by the establishment and maintenance of direct implant-bone connection: "osseointegration".
authors.affiliation: Department of Biomaterials Research, Institute of Surgical Sciences, University of Gothenburg, Sweden. lars.v.carlsson@vgregion.se
authors.forename: Lars V
authors.initials: LV
authors.lastname: Carlsson
authors.forename: Björn E J
authors.initials: BE
authors.lastname: Albrektsson
authors.forename: Björn G
authors.initials: BG
authors.lastname: Albrektsson
authors.forename: Tomas O
authors.initials: TO
authors.lastname: Albrektsson
authors.forename: C Magnus
authors.initials: CM
authors.lastname: Jacobsson
authors.forename: Warren
authors.initials: W
authors.lastname: Macdonald
authors.forename: Lars
authors.initials: L
authors.lastname: Regnér
authors.forename: Tord
authors.initials: T
authors.lastname: Röstlund
authors.forename: Lars R
authors.initials: LR
authors.lastname: Weidenhielm
mesh_terms: D000077:Acetabulum / Q000601:surgery; D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation / Q000379:methods*; D002484:Cementation; D005260:Female; D005269:Femur / Q000601:surgery; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D016348:Osseointegration; D015207:Osteoarthritis, Hip / Q000601:surgery; D010780:Photogrammetry; D011474:Prosthesis Design; D011475:Prosthesis Failure; D014025:Titanium; D016896:Treatment Outcome
chemical_list: D014025:Titanium