2001 Volume 15 Issue 3 Pages 191-198
We present our experience using a 40%-porous hydroxyapatite (HAP) spacer in 17 patients undergoing anterior cervical fusion. Of the 20 total HAP spacers inserted, linear fractures were observed in eight spacers and three spacers collapsed. Spacer fracture was most frequently observed at a mean of two months following insertion with a range from two weeks to 12 months after implantation. In three cases showing collapse of the spacer, two were reoperated on using an iliac bone graft. Histological studies revealed that new bone formation was not observed within the pores of the broken spacers. These findings suggest that 40%-porous HAP spacer, because of its fragility, would appear to be unsuitable for use as a graft material in anterior cervical fusion procedures.
