Loss of tibial bone density in patients with rotating- or fixed-platform TKA.
Little is known about tibial bone remodeling with TKA and its clinical relevance. We performed a randomized clinical trial to compare tibial bone density changes in cemented components with different bearing designs. Bone density changes were assessed using quantitative computed tomography (qCT)-assisted osteodensitometry. Twenty-eight rotating-platform and 26 fixed-platform cemented TKAs were included. The nonoperated contralateral side was used as a control. CT scans were performed postoperatively and 1 year and 2 years after the index operation. Cancellous bone density loss (up to 12.6% at 2 years) was observed in all proximal tibial regions in both cohorts. In contrast, we found lower cortical bone density loss (up to 3.6% at 2 years). We found no differences in bone loss between fixed- and rotating-platform implants. The decrease of cancellous bone density after TKA suggests stress transfer to the cortical bone.
Munro
Jacob T
JT
Auckland Bioengineering Institute, University of Auckland, Level 6, 70 Symonds Street, Private Bag 92019, Auckland Mail Centre, Auckland 1142, New Zealand. jacob.munro@auckland.ac.nz
Pandit
Salil
S
Walker
Cameron G
CG
Clatworthy
Mark
M
Pitto
Rocco P
RP