Effects Of Gentamicin-PDLLA-coated Kirschner Wire On Postoperative Infection Prophylaxis In Rabbits

Infections associated with open fractures after surgical treatment are challenging complications in the clinic.In this study,we developed a rabbit fracture model of acute destructive infections in order to evaluate the antimicrobial efficacy,drug release profile in vivo,biocompatibility and the effects on fracture healing of the gentamicin-PDLLA-coated Kirschner wire drug delivery system.The animals were sacrificed after 56 days and clinical,radiological,laboratory,microbiological and histological assessment were carried out.All animals of group I remained sterile.All animals of group II developed postoperative infection(100%).Whereas,a significantly reduction of infection rates(30%)and higher RUST scores(11.00±1.33)were observed in group III compared to group II(100%,7.20±2.44,separately).Systemic gentamicin concentrations reached the highest values within the first 2 hours,a burst of the drug was released in the first 3 days,and sustained release for at least 28 days.The excretion of gentamicin in the urine presented a descending trend.Values of the liver and kidney function index showed no difference throughout the experimental period.Thus,the gentamicin-PDLLA-coated Kirschner wire was effective in prophylaxis of infection in this contaminated open fracture model of rabbit.Moreover,this system can maintain a relatively durable drug release profile and has a good biocompatibility,also the fracture healing procedure was not disrupted.