Establishment of a dog model of pyogenic spinal infection / 中国组织工程研究

ABSTRACT

BACKGROUND:Spine infection models are rarely reported in the literature. There are fewer reports on the imaging and histological observations of the animal model of spinal infection. OBJECTIVE:To develop a canine model of pyogenic spinal infection. METHODS:Twelve Chinese dogs were adopted in the study. The dogs were in the right arm recumbent. The surgery was conducted by retroperitoneal approach to expose T12/L1 intervertebral space. The intervertebral discs that exposed the intervertebral space were partial y removed, and the end plate of the adjacent two vertebrae was deliberately curetted out. Suspension with different concentrations of Staphylococcus aureus and sodium morrhuate were injected into the dog intervertebral space. The aim of removal of partial intervertebral discs and destruction of endplate was to make the vertebral body bone better in contact with the bacteria. The same operation was conducted in L5/6 clearance of the animal spine. At 14 days after surgery, animals were sacrificed. The infected intervertebral disc and adjacent vertebral bodies were taken out. Bacterial contents of specimens were quantitatively determined. During sacrificing, partial liver tissues and blood samples were col ected for bacterial culture. The occurrence of systemic infection was observed. RESULTS AND CONCLUSION:(1) Spondylodiscitis of the lumbar spinal column was consistently produced in 90%(9/10) the sites chal enged with 102 colony-forming units (CFU) Staphylococcus aureus. Liver biopsy and blood culture did not show any signs of systematic infections. (2) Two out of four animals implanted the suspension with a concentration higher than 103 CFUs died within 3 days post-implantation. (3) These results suggested that a new canine model of pyogenic spinal infection was developed. This model could be used to test the efficacy of different anti-infection strategies.