Initial Stability of the Stem Fixed by Impaction Grafting Technique with Hydroxyapatite Granules in Revision THA

Abstract

In revision THA with bone defects, impaction bone grafting is one proposed solution. Morsellized allografts are commonly used, however allograft has some disadvantages. We tried to use hydroxyapatite (HA) granules in stead of morsellized allografts. Three types of HA granules were prepared. To facilitate the manipulation of HA granules, we tried to add arginine amino acid as glue. These granules were impacted into the plastic femoral canal and collarless polished tapered stem was fixed with PMMA bone cement. Cyclic compression test and torsional test were performed using an Instron type mechanical tester. Mechanical stability of the stem fixed with HA granules for impaction grafting was superior to morsellized allografts. Adding arginine amino acid to HA granules, impaction technique became easier and the initial stability of the stem was improved.