The Effect of Absorbable Calcium Sulfate on Wear Rates in Ultra-high–Molecular-weight Polyethylene: Potential Implications for Its Use in Treating Arthroplasty Infections
Patients, hospitals, and healthcare systems incur substantial burdens when infections result in total joint revisions. One potential solution to mitigate some of these burdens may be to transition from a two-stage infection treatment to a single-stage procedure. Off-label use of an absorbable calcium sulfate antibiotic carrier has been implemented in single-stage and two-stage procedures globally, with the goal of moving toward more single-stage revisions in the United States. Adverse effects of calcium sulfate on the joint space during articulation are currently unknown.Methods:
This study aims to determine the impact of calcium sulfate beads on wear of polyethylene during and following exposure. Two phases of in vitro pin-on-disk testing were conducted. The first phase exposed polyethylene pins to calcium sulfate for 500,000 cycles of a 2-million cycle test. The second phase examined the wear of pins that were created from retrieved components exposed to calcium sulfate in vivo.Results:
No clinically significant difference was observed between the wear rates of the calcium sulfate–exposed polyethylene pins and the control polyethylene pins.Discussion:
Preliminary results suggest that a substantial increase in the wear rate of polyethylene is not expected with the addition of calcium sulfate beads during treatment of infection.