title: Can cemented dual-mobility cups be used without a reinforcement device in cases of mild acetabular bone stock alteration in total hip arthroplasty?
abstract: BACKGROUND
  Cemented versions of dual-mobility cups (DMCs), helpful in cases of bone stock alteration, are usually used in association with a reinforcement device. To simplify the intervention in elderly subjects or those with a poor bone stock, the cups can be cemented directly into the bone, but the long-term result remains uncertain. We conducted a retrospective study in this population so as to: (1) assess whether cemented fixation of a DMC without a reinforcement device leads to a higher loosening rate, (2) confirm its efficacy in preventing dislocations in subjects at high risk of instability, and (3) measure the functional results.
  
  
  OBJECTIVE
  Cemented fixation of a DMC is reliable in cases of moderate alteration of bone stock.
  
  
  METHODS
  Sixty-four patients (66 hips) undergoing implantation of a cemented DMC (Saturne™) without a reinforcement device were included in this single-center retrospective study. Their mean age was 79.8 years (range, 40-95 years). The indications varied: hip osteoarthritis (30.3%), prosthesis revision (44.0%), and trauma (25.8%). The patients were evaluated radiologically and clinically at follow-up. The main evaluation criterion was the revision rate for aseptic loosening. Dislocations, the infection rate, and the Postel Merle d'Aubigné (PMA) score were noted.
  
  
  RESULTS
  At the mean follow-up of 4.2 years, three (4.6%) patients had been lost to follow-up and 22 (33.3%) had died. There was one case of aseptic loosening (1.5%). Cup survival was 98% at 5 years (95%CI [94-100]). There were no dislocations. There was one revision for infection. The mean PMA score was 15.5 (range, 9-18).
  
  
  CONCLUSIONS
  The frequency of acetabular loosening was comparable to the frequency in cemented DMCs with a reinforcement device. A cemented DMC without a reinforcement device is possible and is a simple and viable option when there is moderate bone stock alteration.
  
  
  METHODS
  IV, retrospective cohort study.
authors.affiliation: Service de chirurgie orthopédique, hôpital Raymond-Poincaré, AP-HP, 104, boulevard Raymond-Poincaré, 92380 Garches, France. Electronic address: tx_haen@outlook.com.
authors.forename: T X
authors.initials: TX
authors.lastname: Haen
authors.affiliation: Service de chirurgie orthopédique, hôpital européen George-Pompidou, AP-HP, 20, rue Leblanc, 75015 Paris, France.
authors.forename: G
authors.initials: G
authors.lastname: Lonjon
authors.affiliation: Service de chirurgie orthopédique, hôpital européen George-Pompidou, AP-HP, 20, rue Leblanc, 75015 Paris, France.
authors.forename: E
authors.initials: E
authors.lastname: Vandenbussche
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods*; D001843:Bone Cements; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006621:Hip Joint / Q000503:physiopathology*; D006622:Hip Prosthesis / Q000009:adverse effects*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery; D011474:Prosthesis Design; D011475:Prosthesis Failure; D016459:Prosthesis-Related Infections / Q000209:etiology / Q000601:surgery; D012086:Reoperation / Q000379:methods; D012189:Retrospective Studies; D012306:Risk; D012307:Risk Factors; D013997:Time Factors
chemical_list: D001843:Bone Cements
keywords: Bone cement; Dislocation; Dual mobility; Hip arthroplasty; Instability; Loosening