title: Periprosthetic femoral bone loss in total hip arthroplasty: systematic analysis of the effect of stem design.
abstract: BACKGROUND
  Periprosthetic bone loss may lead to major complications in total hip arthroplasty (THA), including loosening, migration, and even fracture. This study analysed the influence of femoral implant designs on periprosthetic bone mineral density (BMD) after THA.
  
  
  METHODS
  The results of all previous published studies reporting periprosthetic femoral BMD following THA were compiled. Using these results, we compared percent changes in bone loss as a function of: femoral stem fixation, material, and geometry.
  
  
  RESULTS
  The greatest bone loss was in the calcar region (Gruen Zone 7). Overall, cemented stems had more bone loss distally than noncemented stems, while noncemented stems had more proximal bone loss than cemented stems. Within noncemented stems, cobalt-chromium (CoCr) stems had nearly double the proximal bone loss compared to titanium (Ti) alloy stems. Finally, within noncemented titanium alloy group, straight stems had less bone loss than anatomical, tapered, and press-fit designs.
  
  
  CONCLUSIONS
  The findings from the present study quantified percent changes in periprosthetic BMD as a function of fixation method, alloy, and stem design. While no one stem type was identified as ideal, we now have a clearer understanding of the influence of stem design on load transfer to the surrounding bone.
authors: J. Vernon Luck, Sr., M.D. Orthopaedic Research Center Orthopaedic Institute for Children, Los Angeles, California - USA.|University of California, Los Angeles, California - USA.
authors: Ashleen R
authors: AR
authors: Knutsen
authors: J. Vernon Luck, Sr., M.D. Orthopaedic Research Center Orthopaedic Institute for Children, Los Angeles, California - USA.|University of Southern California, Los Angeles, California - USA.
authors: Nicole
authors: N
authors: Lau
authors: University of Southern California, Los Angeles, California - USA.
authors: Donald B
authors: DB
authors: Longjohn
authors: J. Vernon Luck, Sr., M.D. Orthopaedic Research Center Orthopaedic Institute for Children, Los Angeles, California - USA.|University of California, Los Angeles, California - USA.
authors: Edward
authors: E
authors: Ebramzadeh
authors: J. Vernon Luck, Sr., M.D. Orthopaedic Research Center Orthopaedic Institute for Children, Los Angeles, California - USA.|University of California, Los Angeles, California - USA.
authors: Sophia N
authors: SN
authors: Sangiorgio
mesh_terms: D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000379:methods; D015519:Bone Density / Q000502:physiology*; D015331:Cohort Studies; D005260:Female; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000000981:diagnostic imaging / Q000601:surgery; D010024:Osteoporosis / Q000000981:diagnostic imaging / Q000601:surgery*; D057068:Periprosthetic Fractures / Q000000981:diagnostic imaging / Q000601:surgery; D011379:Prognosis; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012086:Reoperation; D012189:Retrospective Studies; D018570:Risk Assessment; D016896:Treatment Outcome