title: Spontaneous dislocation of the polyethylene component following knee revision arthroplasty: case report.
abstract: Dislocation of the polyethylene component in knee arthroplasty is a rare complication. The main triggering factor is failure of the locking mechanism, which may result from technical errors of insertion, trauma or even implant failure. Here, a case of dislocation of the polyethylene component from the tibial base, nine years after revision arthroplasty, is reported. It is believed that this is the first such case reported in the Brazilian literature.
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Eduardo Zaniol
authors.initials: EZ
authors.lastname: Migon
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Geraldo Luiz Schuck
authors.initials: GL
authors.lastname: de Freitas
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Marcos Wainberg
authors.initials: MW
authors.lastname: Rodrigues
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Gustavo Kaempf
authors.initials: GK
authors.lastname: de Oliveira
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Luis Gustavo Morato Pinto
authors.initials: LG
authors.lastname: de Almeida
authors.affiliation: Orthopedics and Traumatology Service, Santa Casa de Porto Alegre, Porto Alegre, RS, Brazil.
authors.forename: Carlos Roberto
authors.initials: CR
authors.lastname: Schwartsmann
keywords: Knee arthroplasty; Polyethylene; Prosthesis failure