Extensively Porous-Coated Stems Demonstrate Excellent Long-Term Survivorship in Revision Total Hip Arthroplasty

J Arthroplasty. 2023 Jul;38(7S):S217-S222. doi: 10.1016/j.arth.2023.03.004. Epub 2023 Mar 10.

Abstract

Background: Extensively porous-coated cylindrical stems have demonstrated excellent results in revision total hip arthroplasties (THAs). However, most studies are midterm follow-ups and of modest cohort size. This study aimed to evaluate long-term outcomes of a large series of extensively porous-coated stems.

Methods: From 1992 to 2003, 925 extensively porous-coated stems were utilized in revision THAs at a single institution. The mean age was 65 years, and 57% of patients were males. Harris hip scores were calculated, and clinical outcomes were assessed. Radiographic assessment for stem fixation was categorized as either in-grown, fibrous stable, or loose according to Engh criteria. Risk analysis used Cox proportional hazard method. The mean follow-up was 13 years.

Results: Mean Harris hip scores improved from 56 to 80 at the last follow-up (P < .001). Fifty-three femoral stems (5%) were rerevised: 26 for aseptic loosening, 11 for stem fractures, 8 for infection, 5 for periprosthetic femoral fractures, and 3 for dislocation. Cumulative incidence of aseptic femoral loosening and femoral rerevision for any reason were 3% and 6.4% at 20 years, respectively. Nine of eleven stem fractures occurred with 10.5-13.5 mm diameters (mean 6 years). Radiographic review of unrevized stems demonstrated 94% bone-ingrown. Demographics, femoral bone loss, stem diameter, and length were not predictors of femoral rerevision.

Conclusion: In this large series of revision THAs using a single extensively porous-coated stem design, the cumulative incidence of rerevision for aseptic femoral loosening was 3% at 20 years. These data confirm the durability of this stem in femoral revision, providing a long-term benchmark for newer uncemented revision stems.

Level of evidence: Level IV, retrospective study.

Keywords: femoral bone loss; long-term survivorship; paprosky; revision total hip arthroplasty (THA); stem fracture.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, N.I.H., Extramural

MeSH terms

  • Aged
  • Arthroplasty, Replacement, Hip* / adverse effects
  • Female
  • Follow-Up Studies
  • Hip Prosthesis*
  • Humans
  • Male
  • Periprosthetic Fractures* / etiology
  • Periprosthetic Fractures* / surgery
  • Porosity
  • Prosthesis Design
  • Prosthesis Failure
  • Reoperation
  • Retrospective Studies
  • Survivorship
  • Treatment Outcome