Comparison of cortical bone trajectory versus pedicle screw techniques in lumbar fusion surgery: A meta-analysis.

BACKGROUND: Biomechanical studies have demonstrated that cortical bone trajectory (CBT) screw can provide a 30% increase in uniaxial yield pullout load than pedicle screw (PS). In addition, the insertion torque of CBT screw is 1.71 times higher than that of PS. A meta-analysis was conducted to evaluate clinical results between CBT screw technique and PS technique in lumbar fusion surgery. METHODS: An extensive search of literature was performed in PubMed, Embase, the Cochrane library. The following outcomes were extracted: visual analog scale (VAS), Oswestry disabilities index (ODI), Japanese Orthopaedic Association (JOA) score, complications, fusion rates, hospital stay, incision length, blood loss, and operation time. Data analysis was conducted with RevMan 5.3 and STATA 12.0. RESULTS: A total of 12 studies were included in the final analysis. The results indicated that CBT group with less blood loss [P < .01], less hospital stay [P < .01], and less incision length [P < .01] than PS group. There were no significant differences between 2 groups in other clinical parameters and outcomes. CONCLUSION: CBT technique provided similar clinical outcomes and fusion rates compared to PS technique in lumbar fusion surgery. However, CBT technique provided additional benefits of less blood loss, less hospital stay, and less incision length.

An Optimized Protocol of Azoxymethane-Dextran Sodium Sulfate Induced Colorectal Tumor Model in Mice.

Since azoxymethane (AOM)-dextran sodium sulfate (DSS) induced tumorigenesis was used to explore inflammation-associated carcinogenesis of sporadic colorectal cancer (CRC), different administration modes of AOM or DSS have been reported. In this article we optimized the protocol of the AOM-DSS modeling using C57BL/6 mice for study on sporadic CRC by intraperitoneal injecting AOM solution at a proper concentration with a 100 µl sterile syringe once, feeding with DSS solution for 7 days in a roll and change DSS solution every day. More than 100 C57BL/6 mice had been treated with the optimized protocol, and all mice were demonstrated suffering from colorectal tumors when sacrificed in 8 to 20 weeks after AOM injection. These tumors mainly occurred in distal segment of colorectum with an increase in tumor density, which was similar to CRC in human beings. Tumor per mouse was high, and variation of tumor number per mouse was low. The histology of tumor developed through the defined stage ranged from precursor lesions, adenomatous lesions, adenomas to adenocarcinomas. The modified protocol of AOM-DSS model is easy, cheap, with high tumor formation rate of colorectal tumors.