Circulatory depression in bone after acrylic implantation.

Because of the continuing hazard of post-operative sepsis in joint replacement surgery and the possibility that persistent bone ischemia may be a contributing factor, it is desirable to know the hemodynamic consequences in bone of the implantation of orthopedic acrylic cement. Experiments were carried out on 60 rats. In 30, a bore-hole was made, unilaterally, in the tibia. In another 30, a bore-hole was made in the tibia and a small amount of polymethylmethacrylate cement (Surgical Simplex P) was implanted into the marrow cavity through the bore-hole. By means of 51-Cr labeled red cells and 59-Fe labeled resin particles, the blood volume and blood flow rate in the tibiae were calculated simultaneously as a percentage of the values in the contralateral tibiae. The results showed that at 14 days and 112 days postoperatively, both blood volume and flow were significantly depressed in tibiae in which acrylic cement had been implanted, as compared with tibiae in which only a bore-hole had been made. It was concluded that orthopedic cement implanted into bone renders the bone hypovascular.