Zementierte versus unzementierte Revisions-Hüftarthroplastik mit verdichtetem Knochenallograft - Prospektiv randomisierte Vergleichsstudie mit Jahres-Follow-up

Background: There are only few studies on hip revision using the impaction grafting technique. Furthermore, data on cementless femoral stems as compared to cemented and polished femoral stems are lacking. We wanted to determine whether cementless femoral stems were equally good in preserving bone mineral density around the femoral stem and in functional outcome. Method: Consecutively 14 patients needing hip revisions for aseptic loosening in the stem with bone stock deficiency Paparowsky grade II were randomized into two groups intraoperatively. Morselized fresh-frozen bone allografts were impacted in both groups. The cemented group received polished Landos Fjord-CrCo stems and the uncemented group received the hydroxyapatite-coated Landos Corail-Titan stems. The dual energy X-ray absorptiometry was used to measure bone mineral density around the femoral stem according to Gruen zones. Function was measured by Merle d'Aubigne score. Patients were controlled at 0.5, 3, 6, 9, 12, 18, 24, 36 and 60 months postoperatively. Results: There was no statistical difference between the BMD loss in the cemented vs. the uncemented group. The BMD loss was between 0-10% in distal Gruen zones and was between 10-20% in proximal Gruen zones. Functional scores were similar and reached a plateau of 16 in the Merle d'Aubigne score after 6 months. Conclusions: Cemented technique in hip revisions using morselized bone allograft is as good as uncemented technique in preserving BMD measured by the DEXA method and restoring function in a 5 years follow-up.