REVISION HIP ARTHROPLASTY WITH A DISTALLY LOCKED FEMORAL COMPONENT FOR MASSIVE FEMORAL BONE LOSS

Abstract

Aseptic loosening and osteolysis may cause significant periprosthetic femoral bone destruction, often necessitating bypass of the deficient proximal femur to obtain stable fixation in the distal diaphysis. The purpose of the present study was to report our results of femoral component revision using a distally locked revision femoral stem for the treatment of the severe proximal femoral bone loss.

We evaluated 21 hips in 20 patients who underwent revision hip arthroplasty associated with Paprosky grade-IIIB or IV femoral deficiencies. Three hips were associated with a Vancouver type-B3 periprosthetic femoral fracture. The mean age at the time of revision was 70.8 (51–82) years old with 5 men and 15 women. The mean duration of follow-up was 5.1 years. The femoral implant used for the revision was the Cannulok Revision Prosthesis in 16 hips and the Huckstep interlocking stem in five. Gaps between the stem and the host bone were filled and impacted with bone chips and morselized bone prior to stem insertion.

One femoral implants were resected because of deep infection Subsidence was absent and stable fixation was achieved in all patients. Non-progressive radiolucent lines in zones 1 and 7 according to Gruen’s classification were detected in five cases. Cortical hypertrophy around the interlocking screws were seen in ten cases. No disadvantages or complications of the interlocking screws were observed. All the fractures have united within three to five months. Intraoperative fractures in the diaphyseal area occurred in five hips in which trochanteric osteotomy was used.

A diaphyseal fixation of the femoral stem with distal interlocking screws appears to provide primary axial and rotational stability of the prosthesis and early mobilization. This implant may provide a satisfactory alternative for the management of revision hip surgery in the presence of a loose femoral component with massive bone loss. Longer-term follow-up data from this study will be needed to confirm these outcomes.