title: Femoral revision with a primary cementless stem.
abstract: BACKGROUND
  The use of a primary cementless component is a tempting option for revision total hip arthrosplasty (reTHA), however, the results of this type of revision have not been clearly determined. The goal of this retrospective study was to determine: if revision with a primary anatomical cementless femoral stem gives adequate bone fixation; the rate of secondary subsidence or recurrent loosening; the survival rate with this device.
  
  
  OBJECTIVE
  Revision with a primary anatomical cementless femoral stem results in a low rate of subsidence and recurrent loosening.
  
  
  METHODS
  This retrospective series of 43 reTHA performed between 1994 and 2012 included 43 patients, mean age 66 years old (37-90) with a minimum follow-up of 24months. There were grade 1 (n=24) or 2A (n=19) bone defects according to the Paprosky classification. The causes of revision were: aseptic loosening in 27, septic loosening in 6, malposition of the implant in 7 and periprosthetic fractures in 3. Clinical (Postel Merle d'Aubigné [PMA] and Harris scores), and radiological (subsidence) assessment was performed, as well as survival analysis (with a 95% confidence interval).
  
  
  RESULTS
  All components were changed through posterolateral approach without femorotomy. In four cases de-escalation (use of a primary component for secondary revision of a prior revision component) was performed. There were no perioperative fractures or perforations. After a mean 47months (24-134), the mean PMA score increased from 10 (5-15) to 16 (11-18), and the Harris score from 58 (20-80) to 85 (66-96). Radiological assessment did not show any extensive radiolucencies or secondary subsidence. Only 3 components were placed in a varus position, with no clinical consequences. One patient had subsequent revision for recurrent dislocations. Estimated survival at 80months by Kaplan-Meier analysis was 85% (CI 95%: 64-100%).
  
  
  CONCLUSIONS
  There are very few studies in the literature (7 series) on this topic, which shows the reluctance of surgeons to use this technique. Placement of a primary femoral stem requires good metaphyseal bone quality for primary stability. Thus, the indication is limited to Paprosky 1 and 2A stages. Revision surgery must be performed by endofemoral approach requiring good preoperative planning, as well as knowledge of the explanted component and a revision component must be available, if necessary, in the operating room.
  
  
  METHODS
  Retrospective study, level 4.
authors.affiliation: Centre hospitalier de Cannes, 15, avenue des Broussailles, CS 5008, 06414 Cannes cedex, France. Electronic address: ogastaud.pro@gmail.com.
authors.forename: O
authors.initials: O
authors.lastname: Gastaud
authors.affiliation: Centre hospitalier de Cannes, 15, avenue des Broussailles, CS 5008, 06414 Cannes cedex, France.
authors.forename: P M
authors.initials: PM
authors.lastname: Cambas
authors.affiliation: Centre hospitalier de Cannes, 15, avenue des Broussailles, CS 5008, 06414 Cannes cedex, France.
authors.forename: J
authors.initials: J
authors.lastname: Tabutin
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects / Q000295:instrumentation / Q000379:methods*; D001843:Bone Cements / Q000627:therapeutic use; D005260:Female; D005269:Femur; D006622:Hip Prosthesis / Q000009:adverse effects; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D011474:Prosthesis Design; D011475:Prosthesis Failure / Q000209:etiology*; D060489:Prosthesis Retention / Q000379:methods*; D012086:Reoperation / Q000379:methods; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D001843:Bone Cements
keywords: Primary stem; Revision; Total hip arthroplasty; Uncemented stem