ABSTRACT
BACKGROUND: Posterior internal fixation is one of the most common methods for thoracolumbar fractures. There is a lack of systematic evaluation about the efficacy of injured vertebra pedicle screw fixation(IVPSF)versus short-segment pedicle instrumentation (SSPI) for thoracolumbar fracture. OBJECTIVE: To compare the clinical outcomes of IVPSF and SSPI for single thoracolumbar fracture through a METHODS: A computer-based on-line research of PubMed, Medline, Embase, Cochrane Library, CNKI, and WanFang databases was performed for the studies regarding IVPSF versus SSPI for thoracolumbar fracture from 1990 to 2016. meta-analysis. The randomized controlled trials and cohort studies were collected based on the strict criteria of inclusion and exclusion. A meta-analysis was conducted on Revman5.3 sofeware. RESULTS AND CONCLUSION: (1) Eleven articles were enrolled, including 5 English and 6 Chinese ones, involving 689 patients (328 cases for IVPSF and 361 cases for SSPI). (2) The meta-analysis indicated that the operation time, blood loss and mean hospital stay showed no significant differences between two groups. IVPSF showed more effective than SSPI in the kyphotic angle correction and anterior vertebral height recovery at postoperation and 1-5 years of follow-up. Moreover, the incidence of postoperative fixation failure in IVPSF was lower than that in SSPI. (3) These findings suggest that IVPSF that reduces the postoperative fixation failure rate for thoracolumbar fractures provides better kyphosis correction and restoration of anterior vertebral height at post-operation and 1-5 years of follow-up.
ABSTRACT
Objective To simulate the cervical rotatory manipulation(CRM)in flexion,neutral and extension positions using three-di-mensional finite element,so as to investigate the effect of this manipulation on the displacement and intra-stress of cervical disc in different positions.Methods By using the method of reverse engineering with Mimics 10.01,Geomagic Studio and Solidworks 14.0,a three-dimen-sional geometric CAD model of C5-6was developed from the CT scan images of a normal adult female aged 25 years.The model was import-ed into Ansys Workbench 14.5,and a three-dimensional finite element model was verified and simulated the CRM.The CRM was decom-posed by principium of manipulation in flexion,neutral and extension,respectively.The parameter of mechanics was analyzed with the fi-nite element system.The change of displacement and intra-stress distribution in cervical disc simultaneous were displayed during simulating the manipulation.Results The posterior part of opposite rotary side of annulus fibers was all retracted,and the displacement was toward an-terior,maximal in flexion position,followed as neutral position and minimal in extension position.In the meantime,the posterior part of the rotary side of annulus fibers was expanded into posterior,minimal in flexion position,followed as neutral position and maximal in extension position.The intra-stress in cervical disc was focused on posterior part of opposite rotary side,opposite rotary side and posterior part of the rotary side in flexion position,neutral position and extension position,respectively,maximal in flexion position,followed as extension posi-tion and minimal in neutral position. Conclusion To treat with cervical spondylotic radiculopathy in the perspective of safety of cervical disc,the CRM should rotate to the unaffected side,first in neutral position,second in flexion position if with poor efficacy.Patients with cer-vical spinal stenosis should not be treated with the CRM.