Study design: Comparative study.
Objective: To compare periprosthetic tissue reactions observed after total disc replacement (TDR), total hip arthroplasty (THA), and total knee arthroplasty (TKA) revision surgery.
Summary of background data: Prosthetic wear debris leading to particle disease, followed by osteolysis, is often observed after THA and TKA. Although the presence of polyethylene (PE) particles and periprosthetic inflammation after TDR has been proven recently, osteolysis is rarely observed. The clinical relevance of PE wear debris in the spine remains poorly understood.
Methods: The number, size, and shape of PE particles, as well as quantity and type of inflammatory cells in periprosthetic tissue retrieved during CHARITÉ TDR (n = 22), THA (n = 10), and TKA (n = 4) revision surgery were compared. Tissue samples were stained with hematoxylin/eosin and examined by using light microscopy with bright field and polarized light.
Results: After THA, large numbers of PE particles of size less than 6 μm were observed, which were mainly phagocytosed by macrophages. The TKA group had a broad size range with many larger PE particles and more giant cells. In TDR, the size range was similar to that observed in TKA. However, the smallest particles were the most prevalent with 75% of the particles being less than 6 μm, as seen in revision THA. In TDR, both macrophages and giant cells were present with a higher number of macrophages.
Conclusion: Both small and large PE particles are present after TDR revision surgery compatible with both THA and TKA wear patterns. The similarities between periprosthetic tissue reactions in the different groups may give more insight into the clinical relevance of PE particles and inflammatory cells in the lumbar spine. The current findings may help to improve TDR design as applied from technologies previously developed in THA and TKA with the goal of a longer survival of TDR.