The Basic And Clinicl Study Of The Postoperative Spondylodiscitis

1. To establish rabbit disctitis models and study the methods of prompt diagnosis2. To evaluate the pathogeny and mechanism of the Postoperative spondylodiscitis and to investigate the change of the pathology.3. To study the methods of prompt diagnosis and treatment. Material and methods1. 12 rabbits were classified randomly into two groups,an experiment group(n=8) and a control group(n=4) and were used to make discitis models.In the experiment group ,The staphylococcus aureus was injected into the intervertebral disc of rabbits for inducing to occur the discitis. In the control group,the equal quantity normal saline was injected into the intervertebral disc of rabbits.All rabbits lumbar spine were examined by X-rays or Magnetic resonance inspector (MRI) respectively in the regular time.Biopsies of nuclear pulpous were obtained from experimental intervertebral disc of lumbar spine for pathological examination or bacteria culture after 1 or 4 weeks. Serum C-reactive protein(CRP) and Erythrocyte sedimentation rate (ESR) were continuously monitored and recorded for all rabbits.The comparation of CRP and ESR values was analyzed statistically. 2. 60 rabbits were used to make discitis models,The discitis model was established by injecting staphylococcus aureus directly into the intervertebral disc for inducing to occur the discitis, and were classified randomly into threegroups,20 cases per group(n=20): the conservative group, the prompt operation group, and the delayed operation group.After operation, All rabbits lumbar spine were examined by X-rays respectively in the regular time.Biopsies of nuclear pulpous were obtained from experimental intervertebral disc of lumbar spine for pathological examination or bacteria culture after operation. The time of reduction to normal of the CRP and ESR were compared statistically.The result of treatment of the three groups were compared and analysed. 3. A retrospective analysis of 61 case of the postoperative discitis was made; All cases with discitis were confirmed by clinical data and medical imaging examination.The characteristic of different treatments were evaluated,The duration of back pain,the time of hospitalization, the time of reduction to normal of the CRP and ESR were compared. Results:l.In the experiment group,The intervertebral disc inoculated with bacteria developed pathological evidence of discitis after one week.The levels of CRP and ESR increased obviously,The radiographic evidence of discitis has been observed by MRI, the bacteria culture was found masculine, and the pathological evidence of discitis was found. Comparing with ESR,The peak of CRP occurred earlier, and the decline of the peak was faster and more regular. In the control group,There could not be found any sign of discitis ,the bacteria culture was found negative.2.1n the prompt operation group, intervertebral space narrow was observed in medical image. There could be seen interbody fusion in medical image in the later time. The fibrosis changes were observed in nucleus regions, there is no evidence with destruction of end-plates, the bacteria culture was negative. In the conservative group, all of the discs inoculated with bacterial developed radiographic and pathological evidence of discis, including intervertebral space narrowing, inflammation changes of disc tissue, and destruction of end-plates. There could be seen few interbody fusion in medical image, bacteria was isolated from biopsy. In the delayed operation group. The radiographic and pathological evidence of discitis was similar to those in the conservative group.But the bacteria culture was negative. Quantitative analyses showed that the time of reduction to normal of the CRP and ESR in prompt operation group were better than those in the conservative treatment group or the delayed operation group with a significant diffirence(P<0.05). There was no significant diffirence between delayed operation group and conservative treatment group(P>0.05).3. After the treatment, all the p...