Biodegradable vs non-biodegradable antibiotic delivery devices in the treatment of osteomyelitis

Introduction: Chronic osteomyelitis, or bone infection, is a major worldwide cause of morbidity and mortality, as it is exceptionally hard to treat due to patient and pathogen-associated factors. Successful treatment requires surgical debridement together with long-term, high antibiotic concentrations that are best achieved by local delivery devices, either made of degradable or non-degradable materials. Areas covered: Non-degradable delivery devices are frequently constituted by polymethylmethacrylate-based carriers. Drawbacks are the need to remove the carrier (as the carrier itself may provide a substratum for bacterial colonization), inefficient release kinetics and incompatibility with certain antibiotics. These drawbacks have led to the quest for degradable alternatives, but also devices made of biodegradable calcium sulphate, collagen sponges, calcium phosphate or polylactic acids have their specific disadvantages. Expert opinion: Antibiotic treatment of osteomyelitis with the current degradable and non-degradable delivery devices is effective in the majority of cases. Degradable carriers have an advantage over non-degradable carriers that they do not require surgical removal. Synthetic poly(trimethylene carbonate) may be preferred in the future over currently approved lactic/glycolic acids, because it does not yield acidic degradation products. Moreover, degradable poly(trimethylene carbonate) yields a zero-order release kinetics that may not stimulate development of antibiotic-resistant bacterial strains due to the absence of long-term, low-concentration tail-release.