Avaliação de método para reconstrução acetabular com uso de enxerto ósseo homólogo e implante cimentado

Abstract

OBJECTIVE: To make a clinical and radiographic evaluation of 43 hips in 43 patients submitted to surgical treatment for acetabular reconstruction of the hip after aseptic loosening of the implant, using the classification developed and adopted by the Hip Surgery Service of the Fracture Emergency Unit in Passo Fundo, State of Rio Grande do Sul (Method of the 75 mm). METHODS: A retrospective study was performed with 88 patients (90 hips) submitted to surgical treatment for acetabular reconstruction after aseptic loosening of the implant, from August 1994 to October 2000. Out of those patients, 43 (43 hips) met all inclusion requirements for this study. Migration of an implant longer than 5 mm in any direction, or the progression of radiolucent lines of more than 2 mm in width in the zones limited by DeLee and Charnley, combined with pain were considered a failed reconstruction due to loosening. RESULTS: From the total number of patients evaluated, 29 cases (67.4{%}) were submitted to acetabular reconstruction with "crouton" plicated graft (1 cm³); the other 14 cases (32.6{%}) were submitted to acetabular reconstruction with block graft. The post-operative clinical classification according to the criteria of D'Aubign{è} et al modified by Charnley, considered the results achieved as follows: 83.7{%} satisfactory, and 16.3{%} unsatisfactory, with a minimum follow-up of six years. According to the criteria established, seven patients (16.3{%}) presented reconstruction failure due to loosening: six with the plicated graft (20.7{%} of the 29 grafts with plicated bone) and one with block graft (7.1{%} of the 14 block grafts). On the average, the failures occurred at 7.25 years. CONCLUSION: Based on the results achieved and using the measurement of the pre-operative acetabular cavity (bigger or smaller than 75 mm) as the criterion of indication of the surgical technique to be adopted, the authors conclude that the method had a high rate of survival of the acetabular reconstruction and satisfactory clinical results in 8.3 years of mean follow up. A longer survival was observed in the cases in which bone blocks were used despite the cavity being bigger.