Compression Strength and Porosity of Single-Antibiotic Cement Vacuum-Mixed With Vancomycin

We evaluated the ultimate compression strength (UCS), porosity, and fracture surface roughness of 2 commercially available single-antibiotic bone cements vacuum-mixed with additional amounts of vancomycin (2, 4, 6, and 8 g). At least 8 g could be added to Palacos R + 0.5 g gentamicin (UCS = 75.04 ± 6.64 MPa) and no more than 6 g to Simplex P + 1 g tobramycin (UCS = 78.93 ± 4.98 MPa) to maintain a UCS above the International Organization for Standardization minimum standard (70 MPa). Increasing vancomycin concentration correlated with a decrease in porosity but showed a trend towards greater fracture surface roughness.