Effect of antibiotics on the properties of poly(methylmethacrylate)‐based bone cement

Abstract

The goal of this study was to examine the relationship between gentamicin concentration in Palacos R bone cement (in the mass fraction range of 0-9.4%) and various properties of the cement. The results from the thermal, density, and static compression tests show that gentamicin favors the cement polymerization in its final steps, and forms a diphasic structure with the cement [poly(methylmethacrylate)] matrix. The static compression properties in the dry state are only slightly modified by the presence of the antibiotic. Concerning aging in water at 37 degrees C, two types of behavior can be distinguished: below a critical concentration, approximately 3-4%, the extraction of gentamicin by water is slow and there is only a slight change of static compression properties. In contrast, above this critical concentration, the gentamicin extraction is fast and almost complete after 48 weeks, and there is a considerable loss of static compression properties.

Increased Antibiotic Release from a Bone Cement Containing Bacterial Cellulose

“…Although there is a lack of consensus regarding experimental designs when considering enhancement of the mechanical properties of bone cement [12], the use of antibiotics at dosages of 4 g or greater has resulted in reduced compression strength [7] and fatigue life [13], with values similar to those obtained for the traditional antibiotic cement in this study (Table 4). Our study showed that bone cement incorporating bacterial cellulose maintains its compression strength and fracture toughness even when loaded with 5 g of antibiotic.…”

“…Although increasing the amount of antibiotic incorporated increases the level of its release [7,13], 4 g or greater of antibiotic to 40 g of PMMA powder compromises the compression strength [7,12], fracture toughness [4], and fatigue life [12,13,17] of the material. Therefore, we investigated whether incorporating bacterial cellulose would improve the mechanical strength of bone cement containing 5 g of antibiotics and increase antibiotic release.…”

“…Although increasing the amount of antibiotic in the cement increases antibiotic release [7,13], with at least 3.5 g antibiotics per 40 g PMMA powder being recommended for treating active infections [6,23], a high dose of antibiotics impairs the mechanical properties of the cement [12,13]. Loading greater than 1 g of antibiotics per 40 g of PMMA powder reduces the fatigue performance of the cement by 40% to 60% [4,12,17].…”

“…Loading greater than 1 g of antibiotics per 40 g of PMMA powder reduces the fatigue performance of the cement by 40% to 60% [4,12,17]. With antibiotic loading greater than 2 g of antibiotics per 40 g of PMMA powder, the fracture toughness and compression strength are decreased by 15% [4] and 10% to 15% [4,7], respectively. Therefore, to avoid mechanical weakening of such cements, low doses of incorporated antibiotics (less than 2 g per 40 g of PMMA powder) have been recommended [6,13,22].…”

The effect of vancomycin addition to the compression strength of antibiotic-loaded bone cements

“…Each specimen was measured with a precision calliper between 22 and 26 h after setting, and only specimens with a length of 11.9±1 mm and a diameter of 6 mm were used. The specimens were also inspected macroscopically, and those with flaws, such as voids or powder clots, were excluded, as numerous studies have indicated that antibiotic inclusions may propagate fracture in cement [8,11,18]. …”