Circulatory depression in bone after acrylic implantation

Area of Science:

• Orthopedic Surgery
• Biomedical Engineering
• Vascular Biology

Background:

• Post-operative sepsis remains a significant risk in joint replacement surgery.
• Persistent bone ischemia may contribute to the development of sepsis.
• Understanding the hemodynamic effects of orthopedic cement is crucial.

Purpose of the Study:

• To investigate the hemodynamic consequences of orthopedic acrylic cement implantation in bone.
• To determine the impact of cement on bone blood volume and blood flow rate.

Main Methods:

• Experiments were conducted on 60 rats, with 30 receiving a tibial bore-hole and 30 receiving cement implantation into the bore-hole.
• 51-Cr labeled red cells and 59-Fe labeled resin particles were used to measure blood volume and flow.
• Measurements were taken 14 and 112 days postoperatively, comparing implanted tibiae to contralateral controls.

Main Results:

• Tibiae implanted with acrylic cement showed significantly depressed blood volume compared to controls at both 14 and 112 days.
• Blood flow rate was also significantly reduced in cement-implanted tibiae at both time points.
• These reductions were observed in comparison to tibiae with only a bore-hole, indicating a specific effect of the cement.

Conclusions:

• Implantation of orthopedic cement into bone leads to a hypovascular state.
• The reduced vascularity in the bone may have implications for healing and infection risk.
• Further research is warranted to explore the clinical significance of cement-induced hypovascularity.