We conducted a randomized clinical trial to compare periacetabular bone density changes after total hip arthroplasty using
press-fit components with soft and hard liner materials. Bone density changes were assessed using quantitative computed tomography-assisted
osteodensitometry. Twenty press-fit cups with alumina ceramic liners and 20 press-fit cups with highly cross-linked polyethylene
liners were included; the nonoperated contralateral side was used as the control. Computed tomography scans were performed
postoperatively and 1 year after the index operation. At the 1-year followup, we found no differences of periacetabular bone
density changes between the alumina and polyethylene liner cohorts. However, we observed marked periacetabular cancellous
bone density loss (up to −34%) in both cohorts. In contrast, we observed only moderate cortical bone density changes. The
decrease of periacetabular cancellous bone density with retention of cortical bone density after THA suggests stress transfer
to the cortical bone.
One or more of the authors have received funding from the Wishbone Trust New Zealand (RPP) and Zimmer, Warsaw, IN (RPP).
Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations
were conducted in conformity with ethical principles of research, and that informed consent was obtained.