Antibiotic Release from Lactose-Containing, Two-Solution Bone Cements

Acrylic bone cements are used primarily for prosthesis augmentation in cemented arthroplasties. Due to the considerable risk of infection in primary and revision surgeries, cement formulations are commercially available with added antimicrobial agents that act as prophylaxes against bacterial infection. A current challenge with antibiotic-loaded acrylic bone cements (ALABCs) is the limited antibiotic release. The two-solution bone cement (TSBC) was developed as a more effective alternative to traditional powder-liquid cement formulations. TSBCs are pre-mixed and therefore enable addition of other filler phases in the cement matrix. Lactose has shown promise as a release-promoting filler material because it creates pores in the cement’s acrylic matrix, allowing for improved antibiotic release. In this study, TSBCs were infused with lactose and an antibiotic (chlorhexidine). The aim was to determine if the addition of lactose would increase the amount of antibiotic released from the cements. Cement formulations were tested for compressive strength, pseudoplasticity, and antibiotic release. The data demonstrated the compressive strengths of the lactose-loaded cements were slightly reduced but remained acceptable per ASTM standards, the pseudoplasticity was preserved, and the antibiotic release was markedly greater than that of regular bone cements. The results suggest the addition of lactose could considerably improve the antibiotic release of clinical bone cements.