The purpose of this study was to determine the natural history of @entity77 pellets implanted during @entity174 surgery. The study group consisted of @entity1 sustaining an @entity174 with intraarticular comminution or marginal impaction or both in whom @entity77 pellets were implanted in lieu of autologous bone graft. Between 1997 and 1999, 32 @entity174 were treated. Followup adequate to delineate pellet outcome, including radiographs and computed tomography, was obtained in 31 @entity1 . Evaluation of plain radiographs showed that the @entity77 pellets became undifferentiated from the surrounding bone at an average of 7 weeks postoperatively. In no case was a residual bony deficit seen. Computed tomography analysis showed that in 22 @entity1 , the pellets essentially had been (> 90%) replaced by bone and in four @entity1 , the majority (> 50%-90%) of the pellets had been replaced by bone. However, in five @entity1 , less than 50% of the pellets had been replaced by bone, including one showing no bony replacement. The common finding in @entity1 with an extensive residual deficit was direct communication of the pellets with the joint space shown on the postoperative computed tomography scan. @entity1 with the best results had complete containment of the pellets within bone. Therefore, it seems that implanted @entity77 pellets in contact with joint synovial fluid are at risk for resorption without significant bony response. If @entity77 pellets are to be implanted in a periarticular location, complete bony containment is desirable. Evaluation of the periacetabular bony response requires computed tomography scans, as plain radiographs are inadequate for this purpose.

XXXX used as bone graft substitute in @entity174 fixation.

@entity1 :: ('9606', 'Species') :: ['Patients', 'patients'] @entity77 :: ('MESH:D002133', 'Chemical') :: ['calcium sulfate'] @entity174 :: ('MESH:D050723', 'Disease') :: ['fractures', 'acetabular fracture']
@entity77 :: (MESH:D002133,Chemical) :: ['Calcium sulfate']
