ABSTRACT
To evaluate the possibility of the newly developed highly porous glass ceramics as a space-filler in the cavitary bone defect, we made the opening sized 1 × 0.5 cm on the medial aspect of the right proximal tibia of nine rabbits. We impacted the highly porous glass ceramics firmly to the medullary cavity of rabbit tibia through the opening. Each three were sacrificed at 4th, 8th, and 12th week and analyze in vivo reaction of the glass ceramics in rabbit tibia with radiological and histological methods. On radiological examination, radiolucent line was seen around impacted glass ceramics at 4th week, but this radiolucent line was obliterated gradually to 12th week. On histological examination, new bone formation with osteoblast was appeared at 4th week without foreign body reactions. At 8th week, newly formed bone infiltrated into the porous space between glass ceramics particles was noticed, and the surface of glass ceramics was tightly bound by newly formed bone with osteoblastic rim and mature bone, At 12th week, the amount of newly formed mature bone increased, though there was on evidence of resorption of glass ceramics particle. So, we suggest that the highly porous glass ceramics is one of the possible artificial bone graft substitutes, especially as a space-filler.
Subject(s)
Rabbits , Ceramics , Foreign Bodies , Glass , Osteoblasts , Osteogenesis , Tibia , TransplantsABSTRACT
The purpose of this study is to evaluate the results of the reconstruction of acetabular bone defect with morselized bone graft in revision of failed acetabular cup, used screw fixed hemispherical cup or bipolar cup as a component. Forty five revisions of an acetabular component that had been performed in 42 patients between 1988 and 1993 at SNUH, and had followed more than two years were included in this study. The revised acetabulum was evaluated by Harris hip score, in terms of osseous union and resorption of the graft, the amount of the migration of the revised components. Cup angle change and radiolucency were also evaluated in screw fixed hemispherical cup. The mean Harris hip score was improved 54 to 87 in screw fixed hemispherical cup and 56 to 78 in bipolar cup. In screw fixed hemispherical cup, osseous union showed within 6 months is 91.3% (21 cases), the graft bone resorption less than 10% of the initial graft thickness is 73.9% (17 cases). In bipolar cup, osseous union within 6 months is 52.2% (12 cases), the graft bone resorption less than 10% of the initial graft thickness is 40.9% (9 cases). The failure of revised acetabular component was five in bipolar cup cases and one in screw fixed hemispherical cup cases. In conclusion, screw fixed hemispherical cup showed better clinical results, earlier graft osseous union, less graft bone resorption and lower failure rate than bipolar cup. There was no significant difference between pure allograft mixed with autograft in clinical and radiological results. So we recommend the technique used morselized allograft with screw fixed hemispherical cup, to reconstruct the acetabular bone defect in acetabular cup revision, though bipolar cup was used in staged operation in severe acetabular bone defect with was unable to fix the acetabular cup with screws.