Revisão de artroplastia unicompartimental de joelho: implantes usados e causas de falha

ResumoObjetivoDeterminar as causas de falha da artroplastia Unicondilar, assim como identificar os implantes utilizados e a possível necessidade de enxertia óssea nos pacientes submetidos à cirurgia de revisão de AUJ no Centro de Cirurgia do Joelho do Instituto Nacional de Traumatologia e Ortopedia ‐ INTO, no período entre janeiro de 1990 a janeiro de 2013 foram analisados.MétodosAnálise retrospectiva da documentação médica e exames de imagem, determinando‐se a causa da falha da AUJ e o momento de sua ocorrência, assim como os componentes protéticos implantados durante a revisão e a necessidade de enxertia óssea.ResultadosForam incluídos nesta série 27 falhas de revisão de AUJ (26 pacientes). Colapso (afundamento) de um ou mais componentes representou a principal causa de falha, ocorrendo em 33% dos pacientes, soltura asséptica foi identificado em 30% dos casos, por progressão da osteoartrose em 15%, infecção e dor em 7% cada, desgaste do polietileno e osteólise em 4% cada. Falha precoce ocorreu em 41% de todas as indicações de revisões e falha tardia em 59%. A cirurgia de revisão da artroplastia unicompartimental foi realizada em 23 pacientes.ConclusõesEm 35% das cirurgias de revisão foi necessária enxertia óssea no lado tibial, sendo três casos necessário enxerto homólogo de Banco de Tecidos Músculo Esquelético. Não utilizamos aumento metálico em nenhum caso. Em um caso foi implantado prótese semiconstrita por instabilidade.AbstractObjectiveDetermine the causes of unicondylar knee arthroplasty failures, as well as identify the implants used and the need of bone grafting in patients undergoing revision UKA in Center of Knee Surgery at the Instituto Nacional de Traumatologia e Ortopedia (INTO) in the period between January 1990 and January 2013.MethodsA retrospective analysis of the medical documentation and imaging, determining the cause of failure of UKA and the time of its occurrence, as well as prosthetic components implanted during the review and the need for bone grafting.ResultsIn this study, were included 27 UKA failures in 26 patients. Colapse of one or more components was the main cause of failure, occurring in 33% of patients. Aseptic failure was identified in 30% of cases, progression of osteoarthrosis in 15%, infection and pain 7% each, and osteolisis and poliethilene failure in 4% each. Early failure occurred in 41% of all revisions of UKA and late failure in 59%. 23 patients have undergone revision of UK.ConclusionIn 35% of revisions was needed the use of bone grafting in tibial area; in 3 cases we needed allograft from Tissue Bank. We didn’t use metal increase in any of the revision. In one patient we used implant constraint for instability

Revision of unicompartmental knee arthroplasty: implants used and causes of failure

OBJECTIVE: to determine the causes of unicondylar knee arthroplasty failures, as well as identify the implants used and the need of bone grafting in patients undergoing revision UKA in Center of Knee Surgery at the Instituto Nacional de Traumatologia e Ortopedia (INTO) in the period between January 1990 and January 2013.METHODS: a retrospective analysis of the medical documentation and imaging, determining the cause of failure of UKA and the time of its occurrence, as well as prosthetic components implanted during the review and the need for bone grafting.RESULTS: in this study, 27 UKA failures in 26 patients were included. Collapse of one or more components was the main cause of failure, occurring in 33% of patients. Aseptic failure was identified in 30% of cases, progression of osteoarthrosis in 15%, infection and pain 7% each, and osteolysis and polyethylene failure in 4% each. Early failure occurred in 41% of all revisions of UKA and late failure in 59%. 23 patients have undergone revision of UK.CONCLUSION: in 35% of revisions the use of bone grafting was needed in tibial area; in 3 cases we needed allograft from Tissue Bank. We did not use metal increase in any of the revision. In one patient we used implant constraint for instability