088 THE USE OF ULTRASONIC DEVICES AS AN ADJUNCT TO REVISION OF CEMENTED FEMORAL TOTAL HIP ARTHROPLASTY COMPONENTS

Abstract

In revision of cemented femoral components, removal of cement can be challenging. This study evaluates the use of an ultrasonic device (OSCAR, Orthosonics Ltd UK) for cement removal.

30 consecutive patients that attended our outpatients\’ clinic between May 2008 and September 2008, who underwent revision THR by the senior author or his fellows, were retrospectively reviewed. Minimum follow up was 12 months (average 34.9 months).Indications were aseptic loosening and recurrent dislocation. A posterolateral approach was used routinely. Cement was removed with osteotomes and OSCAR. An uncemented modular femoral component was used. At follow-up, radiographs were evaluated for the evidence of extended trochanteric osteotomy (ETO), fracture, cortical perforation, component loosening, migration, and adequacy of cement removal.

None of the cases required an ETO or cortical windowing. In 5 cases prophylactic cabling of the proximal femur was performed. There was one intraoperative femoral shaft fracture (3.33%). There was incomplete cement removal in 7 cases. There was no cortical perforation and no postoperative fracture. There was no case with loosening or migration of the implant.

In all cases that OSCAR was used ETO and cortical windowing were avoided. At an average 34.9 month follow up there was no evidence of thermal tissue damage. In the cases that cement was retained in the canal, this did not affect the stability of the implant. The fracture and the incomplete cement removal were in cases performed by a fellow illustrating the learning curve of the technique.