title: Acetabular reconstruction using morselized allograft and a reinforcement ring for revision arthroplasty with Paprosky type II and III bone loss: survival analysis of 95 hips after 5 to 13 years.
abstract: BACKGROUND
  Treatment of acetabular loosening and accompanying bone defects requires that the bone stock be rebuilt, the primary stability ensured, and the hip center of rotation restored to its anatomical location.
  
  
  OBJECTIVE
  Acetabular reconstruction using morselized allograft and a reinforcement ring will meet these requirements and ensure medium-term survival.
  
  
  METHODS
  A retrospective study was performed on 95 acetabular revision cases (95 patients) performed between 1987 and 1995. The average age at revision was 69.5 years (42 to 86 years). Among these acetabular loosening cases, 12 cases had a type II Paprosky acetabular bone defect and 83 cases had a type III defect.
  
  
  RESULTS
  The average follow-up was 8 years (5 to 13 years). There were seven post-operative dislocations, three deep infections, and two cases of repeated acetabular loosening. The cumulative survival rate at 14 years was 77.9% (95% CI: 61.96% to 93.84%). The average Postel Merle d'Aubigné (PMA) score improved from 8 (range 6-11) preoperatively to 14.8 (range 8-18) at follow-up; the Harris score improved from 35.3 (range 11-52) to 71.1 (range 40-94) (P<0.001). Based on the parameters outlined by Ranawat, the optimal centre of rotation was restored in 45% of cases. Graft integration was found to be good in 60% of cases. The reinforcement ring had migrated in five cases, including two cases of acetabular loosening that required an additional revision. The functional result was better when the hip center of rotation was restored (P<0.05). Conversely, the position of the hip center of rotation had no effect on graft integration or acetabular fixation.
  
  
  CONCLUSIONS
  This series confirmed that acetabular reconstruction using morselized allograft and a reinforcement ring is effective in the medium term as a treatment for acetabular loosening with severe bone deficiency. It also revealed that restoring the hip center of rotation can improve functional results.
  
  
  METHODS
  Level IV, retrospective study.
authors.affiliation: Émile-Gallé Surgical Center, 49, rue Hermite, CS 75211, 54052 Nancy cedex, France. riphilippe@wanadoo.fr
authors.forename: R
authors.initials: R
authors.lastname: Philippe
authors.forename: O
authors.initials: O
authors.lastname: Gosselin
authors.forename: J
authors.initials: J
authors.lastname: Sedaghatian
authors.forename: C
authors.initials: C
authors.lastname: Dezaly
authors.forename: O
authors.initials: O
authors.lastname: Roche
authors.forename: F
authors.initials: F
authors.lastname: Sirveaux
authors.forename: D
authors.initials: D
authors.lastname: Molé
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000328:Adult; D000369:Aged, 80 and over; D019644:Arthroplasty, Replacement, Hip; D001862:Bone Resorption / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000601:surgery*; D005260:Female; D005270:Femur Head / Q000637:transplantation*; D005500:Follow-Up Studies; D006085:Graft Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D015207:Osteoarthritis, Hip / Q000601:surgery; D011475:Prosthesis Failure; D011859:Radiography; D019651:Plastic Surgery Procedures / Q000379:methods*; D012086:Reoperation / Q000379:methods*; D012189:Retrospective Studies; D013997:Time Factors; D014184:Transplantation, Homologous; D016896:Treatment Outcome