title: CADAVERIC STUDY ON THE LEARNING CURVE OF THE TWO-APPROACH GANZ PERIACETABULAR OSTEOTOMY.
abstract: OBJECTIVE
  : The Bernese periacetabular osteotomy (PAO) is a widely used technique for the treatment of non-arthritic, dysplastic, painful hips. It is considered a highly complex procedure with a steep learning curve. In an attempt to minimize complications, a double anterior-posterior approach has been described. We report on our experience while performing this technique on cadaveric hips followed by meticulous dissection to verify possible complications.
  
  
  METHODS
  : We operated on 15 fresh cadaveric hips using a combined posterior Kocher-Langenbeck and an anterior Smith-Petersen approach, without fluoroscopic control. The PAO cuts were performed and the acetabular fragment was mobilized. A meticulous dissection was carried out to verify the precision of the cuts.
  
  
  RESULTS
  : Complications were observed in seven specimens (46%). They included a posterior column fracture, and posterior and anterior articular fractures. The incidence of complications decreased over time, from 60% in the first five procedures to 20% in the last five procedures.
  
  
  CONCLUSIONS
  : We concluded that PAO using a combined anterior-posterior approach is a reproducible technique that allows all cuts to be done under direct visualization. The steep learning curve described in the classic single incision approach was also observed when using two approaches.
  
  
  METHODS
  IV, Cadaveric Study.
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Fernando Portilho
authors.initials: FP
authors.lastname: Ferro
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Leandro
authors.initials: L
authors.lastname: Ejnisman
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Helder Souza
authors.initials: HS
authors.lastname: Miyahara
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Christiano Augusto de Castro
authors.initials: CA
authors.lastname: Trindade
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: Antônio
authors.initials: A
authors.lastname: Faga
authors.affiliation: . Universidade de São Paulo, Faculdade de Medicina, Hospital das Clínicas, Institute of Orthopedics and Traumatology, São Paulo, SP, Brazil.
authors.forename: José Ricardo Negreiros
authors.initials: JR
authors.lastname: Vicente
keywords: Arthritis; Autopsy; Cadaver; Hip dislocation, Congenital; Osteotomy