BACKGROUND:Short-segment pedicle screw technology has been extensively used in the treatment and repair of thoracolumbar burst fractures. The technique of operative treatment through the paraspinal muscle approach has advantages such as less trauma and bleeding, and rapid recovery. However, it requires further investigations to verify the superiority of the paraspinal muscle approach of two lateral incisions near the posterior median line. OBJECTIVE:To evaluate the clinical efficacy and Cobb’s angle of short-segment pedicle screw fixation through paraspinal muscle approach of two lateral incisions near the posterior median line in the treatment of thoracic and lumbar fractures. METHODS:From September 2010 to June 2012, 56 patients with thoracic and lumbar fractures were included in the retrospective study, including 42 males and14 females, with an average of 45 years (range 18-59 years). According to the surgical approach, patients were divided into two groups, traditional approach (n=25) and paraspinal muscle approach (n=31). The operative time, intraoperative blood loss, postoperative drainage and postoperative ambulant time in the two groups were observed and compared. The visual analog scale scores at 7 days, 1 month and 6 months postoperatively were recorded. The Cobb’s angles of suffered vertebra were measured preoperatively and at 7 days and 6 months postoperatively. RESULTS AND CONCLUSION:Al patients were fol owed up after internal fixation. The paraspinal muscle approach was superior to traditional approach in the operation time, intraoperative blood loss, postoperative drainage and postoperative ambulant time, and visual analog scale scores at 7 days and 1 month postoperatively (P<0.05). There was no significant difference between the preoperative and postoperative Cobb’s angle in the two groups (P>0.05). The short-segment pedicle screw fixation through paraspinal muscle approach of two lateral incisions near the posterior median line in the treatment of thoracic and lumbar fractures, is an effective and minimal y invasive treatment, with less trauma, less bleeding, rapid recovery, and simple operations. Similar to open surgery, this treatment can recover the anatomical morphology and reconstruct spinal stability, and had good biocompatibility to the host.

Aim To investigate the role of endoplasmic reticulum stress in adenosine induced HepG2 cell apoptosis.Methods HepG2 cells were treated with different concentrations of ADO for 36 h,and the effect of ADO on cell proliferation was measured by MTT assay.Cell nuclei DAPI staining was used to detect the nuclei change after being treated with different concentrations ADO for 36 h or 2.0 mmol?L-1 ADO for different time.The effect of ADO on HepG2 cell cycle was analysed by flow cytometry after being treated with 2.0 mmol?L-1 ADO for 12 h or 24 h.Translocation of CHOP and Caspase-3 were measured by immunofluorescence after being treated with 2.0 mmol?L-1 ADO for 36 h.The proteins expressions of CHOP,Caspase-4,Caspase-3 and JNK were assayed by western blot.Results The viability of HepG2 cell decreased in a dose-dependent manner;the relative cell viability of 0.5,1,2,4,6 mmol?L-1 decreased by 13.48%?0.12%,27.92%?0.25%,35.21%?0.42%,51.46%?0.24%,71.42%?0.58%,compared with the control group respectively.The nuclei of HepG2 cells treated with different ADO concentrations or 2.0 mmol?L-1 ADO showed condensation,rounding and shrinkage,then fragmentation,which demonstrated cell apoptosis.After being treated with 2.0 mmol?L-1 ADO for 12 h or 24 h,cell cycle analysis showed sub-G1 phase increased;the apoptotic ratio of control,12 h and 24 h was 1.55%?0.12%,10.96%?0.07% and 21.04%?0.26% respectively.Immunofluorescence assay showed the CHOP and Caspase-3 translocation to the nuclei after being treated with 2.0 mmol?L-1 ADO.The expressions of CHOP,Caspase-3 and Caspase-4 increased after being treated with different concentrations ADO for 36 h,while the expression of JNK did not change.Conclusion Endoplasmic reticulum stress is involved in adenosine-induced HepG2 cell apoptosis.

Objective To comparemodified bone cement injection sleeve (front end closed,unilateral opening) and traditional straight push bone cement sleeve in percutaneous vertebral plasty (PVP) for clinical application.Methods From January 2015 to June 2016,78 patients with PVP indications of single osteoporotic vertebral compression fracture (OVCF) were randomly divided into a study group and a control group (39 patients for each group),and both groups received PVP under DSA.Intraoperative X-ray exposure dose,surgical duration,postoperative bone cement leakage,VAS score (preoperative and postoperative 3 days and 6 months),and refracture rate after half a year and postoperative bone cement distribution were compared between the two groups.Results Both groups received a follow-up for 6 to 12 months.5 patients had paravertebralleakage in the study group,while 9 patients developed paravertebralleakage and orie patient had anterior leakage in the control group.No neurologic and vascular injury occurred,no pulmonary embolism and other serious complications developed.The patients in both groups were followed up for half a year without re-fracture.The radiation dose and surgical duration in the two groups were statistically significant (P＜0.05).Bone cement injection and postoperative VAS scoresdid not differ obviously between the two groups (P＞0.05),There was no significant difference between the two groups in distribution of bone cement (P＞0.05).The bone cement leakage rate was lower in the study group than in the control group,with a statistical significance (P＜0.05).Conclusions The improvement in bone cement injection sleeve can shorten surgical duration,reduce intraoperative X-ray exposure,and decrease the rate of leakage of bone cement.It is worth popularizing clinically.