Abstract
Purpose: The purpose of this work was to assess the quality of the bone reconstruction in contact with the long hydroxyapatite-coated locked femoral stem used in a consecutive series of patients undergoing revision total hip arthroplasty (RTHA).
Material and methods: This series of 20 patients underwent RTHA for aseptic loosening (n=15) or septic loosening (n=5) of an AURA prosthesis. Mean age was 70.5 years. Mean time between insertion of the first stem and revision was 11 years for the aseptic patients and 2.6 years for the septic patients. Bony lesions of the femur were assessed with the SOFCOT classification: grade I=5, grade II=4, grade III=4, and grade IV=1. A transfemoral approach with a floating femoral segment was used in 14 patients and an endofemoral approach in six. The septic loosenings were reconstructed in two operative times in four patients and in one operation in one patient. An AURA reconstruction stem was used in 15 cases and a revision stem in five. A complementary cancellous bone graft with the endofemoral approach was used in six patients.
Results: Two patients died. All others were reviewed at a mean follow-up of 26 months (range 12–46 months) for clinical and radiographic assessment (five patients also had a supplementary scan at more than three years follow-up). We had three dislocations at 15 days with no recurrence and one case of sepsis at three months which cured after wash out and adapted antibiotics. All the femoral segments healed starting on the tenth week. The PMA score improved from 9.1 to 15.66 and the Harris score from 43.5 to 85.5. At last follow-up, all femoral lesions had moved to a lower SOFCOT score. There was a tight contact between the AURA stem and the femur on the last follow-up scan which showed an increase in the cortical index from 1 to 8 cm from the metaphyseal spine of the stem. None of the patients experienced secondary unlocking or required revision for a shorter stem.
Discussion: Revision after femoral failure with bone destruction using a non-cemented hydroxyapatite-coated stem allows immediate prosthetic mechanical stability and intimate bone reconstruction in the metaphyseal diaphyseal region. This reconstruction is real even if a graft is not used and appears to be favoured by the femorotomy. Implantation of the long stem is not particularly difficult and can even make the operation easier. Femorotomy has a real advantage, particularly for the revision of septic stems or in the event of difficult explantation.
The abstracts were prepared by Docteur Jean Barthas. Correspondence should be addressed to him at Secrétariat de la Société S.O.F.C.O.T., 56 rue Boissonade, 75014 Paris.