title: Customised osteotomy guides and endoprosthetic reconstruction for periacetabular tumours.
abstract: OBJECTIVE
  We sought to analyse clinical and oncological outcomes of patients after guided resection of periacetabular tumours and endoprosthetic reconstruction of the remaining defect.
  
  
  METHODS
  From 1988 to 2008, we treated 56 consecutive patients (mean age 52.5 years, 41.1 % women). Patients were followed up either until death or February 2011 (mean follow up 5.5 years, range 0.1-22.5, standard deviation ± 5.3). Kaplan-Meier analysis was used to estimate survival rates.
  
  
  RESULTS
  Disease-specific survival was 59.9 % at five years and 49.7 % at ten and 20 years, respectively. Wide resection margins were achieved in 38 patients, whereas 11 patients underwent marginal and seven intralesional resection. Survival was significantly better in patients with wide or marginal resection than in patients with intralesional resection (p = 0.022). Survival for patients with secondary tumours was significantly worse than for patients with primary tumours (p = 0.003). In 29 patients (51.8 %), at least one reoperation was necessary, resulting in a revision-free survival of 50.5 % at five years, 41.1 % at ten years and 30.6 % at 20 years. Implant survival was 77.0 % at five years, 68.6 % at ten years and 51.8 % at 20 years. A total of 35 patients (62.5 %) experienced one or more complications after surgery. Ten of 56 patients (17.9 %) experienced local recurrence after a mean of 8.9 months. The mean postoperative Musculoskeletal Tumor Society (MSTS) score was 18.1 (60.1 %).
  
  
  CONCLUSIONS
  The surgical approach assessed in this study simplifies the process of tumour resection and prosthesis implantation and leads to acceptable clinical and oncological outcomes.
authors.forename: Boris Michael
authors.initials: BM
authors.lastname: Holzapfel
authors.forename: Hakan
authors.initials: H
authors.lastname: Pilge
authors.forename: Peter Michael
authors.initials: PM
authors.lastname: Prodinger
authors.forename: Andreas
authors.initials: A
authors.lastname: Toepfer
authors.forename: Susanne
authors.initials: S
authors.lastname: Mayer-Wagner
authors.forename: Dietmar Werner
authors.initials: DW
authors.lastname: Hutmacher
authors.forename: Ruediger
authors.initials: R
authors.lastname: von Eisenhart-Rothe
authors.forename: Maximilian
authors.initials: M
authors.lastname: Rudert
authors.forename: Reiner
authors.initials: R
authors.lastname: Gradinger
authors.forename: Hans
authors.initials: H
authors.lastname: Rechl
mesh_terms: D000077:Acetabulum / Q000601:surgery*; D000293:Adolescent; D000328:Adult; D000368:Aged; D001859:Bone Neoplasms / Q000601:surgery*; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional; D008297:Male; D008875:Middle Aged; D010027:Osteotomy / Q000295:instrumentation*; D011474:Prosthesis Design; D019919:Prosthesis Implantation; D019651:Plastic Surgery Procedures; D012509:Sarcoma / Q000601:surgery*; D025321:Surgery, Computer-Assisted; D055815:Young Adult