COMPARISON OF METHODS FOR FEMORAL FIXATION OF ARTICULATING, ANTIBIOTIC-LOADED HIP SPACERS

Abstract

There exist 4 methods for femoral fixation of hip spacers:

1. a simple insertion,

2. a partial/full cementation,

3. the “glove”-technique, and,

4. a cement bridge in case of large osseous defects of the proximal femur.

To our knowledge, it is still unknown which of these methods provides the best stability.

Between 01.01.1999–31.12.2008, 84 hip spacer implantations in 78 patients have been performed in our department. All patients have been treated with the same kind of spacer. 24 spacers have been fixed with the “glove”-technique, 18 with a partial cementation onto the proximal femur, 21 with a simple insertion, and 4 with a cement bridge. In 17 cases with an isolated septic loosening of the acetabular cup, only a spacer head has been placed onto the well-fixed prosthesis stem.

The overall dislocation rate between stages was 21.4 % (18/84). The lowest dislocation rate was observed in the “spacer head” group with 5.8 % (1/17), followed by the “glove”-technique with 12.5 % of the cases (3/24). In the “partial cementation” group the dislocation rate was 22.2 % (4/18), whereas in the “insertion” group spacer dislocations occurred in 9 out of 21 cases (42.8 %). In the latter group, in 3 cases the spacer rotated primarily in the femur and dislocated subsequently out from the acetabulum. From the 4 patients having been treated with a cement bridge, 2 patients suffered from a spacer dislocation. From these 18 cases, 15 patients have been treated conservatively by reduction and immobilization in a hip orthesis during the remaining time between stages. The other three cases underwent further surgical procedures; in one case (combined spacer dislocation and -fracture), the spacer had been exchanged, whereas the other two cases had been treated by resection arthroplasty after recurrent spacer dislocations and unsuccessful conservative treatment.

The “glove”-technique seems to be the most effective method for femoral fixation fixation of hip spacers regarding the prevention of dislocations between stages. Further advantages of this technique include a safe and easy spacer explantation in one piece without cement debris at the second stage.