Early prosthetic complications after unipolar hemiarthroplasty

In Australia, the most frequently used hemiarthroplasty prosthesis for the management of displaced intracapsular femoral neck fractures is the Uncemented Austin Moore (UAM). Despite concerns regarding poor functional outcomes and increased early revision rates associated with the UAM prosthesis, apprehension regarding the systemic side-effects of polymethylmethacrylate cement implantation in the elderly patient continues to influence prosthesis selection. This study examines the incidence of early prosthesis related complications after UAM and Cemented Thompson (CT) hemiarthroplasty procedures for the management of femoral neck fractures.

A multicentre retrospective review of charts and radiographs was conducted in 1118 unipolar hemiarthroplasty implantations to determine early complications associated with the CT and UAM prostheses over a 6-year period in five Queensland public hospitals.

Intraoperative periprosthetic fractures were sustained in 11.8% of UAM and 1.8% of CT implantations (P < 0.0001). Intraoperative periprosthetic fractures were associated with an increased requirement for reoperation within 1 month of the index procedure (P = 0.05). No statistical difference in the incidence of intraoperative periprosthetic fractures could be observed between the hospitals participating, regardless of the proportional use of each prosthesis. Early dislocation rates were similar for the UAM and CT prostheses. The intraoperative mortality rate attributable to the use of polymethylmethacrylate cement during hip hemiarthroplasty was 1/738 (0.14%).

The results of this study support the use of the CT prosthesis for the management of femoral neck fractures to reduce the high incidence of intraoperative periprosthetic fractures and associated requirements for early reoperation experienced with the UAM.