Objective To evaluate the clinical outcome of mono-segment transpedicular fixation of type B thoracolumbar fracture.Methods A retrospective analysis was conducted on 40 cases suffering from type B thoracolumbar fracture treated with mono-segment transpedicular fixation from May 2003 to October 2012.According to the AO classification,13 cases were identified with type B1.1,11 type B1.2,11 type B2.2,2 type B3.1,2 type B3.2,and 1 type B3.3.Radiological results were evaluated by measuring compression rate of the fractured vertebra and Cobb' s angle of the vertebra adjacent to the fractured segment.Clinical results were assessed using Frankel classification for spinal cord injury and visual analogue scale (VAS) for pain.Results Mean operation time was 71 minutes and mean intrao perative blood loss was 105 ml.Mean period of follow-up was 47.5 months (range,24-82 months).Mean Cobb' s angle of the vertebra adjacent to the fractured segment and compression rate of the fractured vertebra revealed great correction at one week post-operation compared with preoperative ones (6.2° vs 20.1° and 10.1％ vs 38.9％ respectively,P ＜0.05) and there was no significant correction loss at the last follow-up (6.9° and 10.8％ respectively,P ＞ 0.05).Mean VAS was 8.6 points before operation,but mean VAS was 2.4 points at final follow-up (P ＜ 0.05).Neurological performance improved in 37 cases (93％).No cases experienced neurological deterioration.Conclusions Mono-segment transpedicular fixation has small incision,short operation time,few bleeding and decreased motor function loss.The procedure is indicated for most type B thoracolumbar fracture and clinical results are satisfactory.

BACKGROUND:Whether controling of post-injury inflammatory response combined with neural stem cel (NSC) transplantation can improve the curative efficacy for spinal cord injury stil remains unclear. OBJECTIVE:To investigate the repair of spinal cord tissue, myelin regeneration, axon regeneration, motor function recovery and the possible mechanism after early application of tumor necrosis factor α antagonist (Etanercept) combined with tyrosine kinase C (TrkC) gene-modified NSC transplantation. METHODS:TrkC-overexpressed NSCs (TrkC-NSCs) were constructed by lentiviral transfection technique. The rat models of spinal cord transection injury were prepared, and then subjected to Etanercept combined with TrkC-NSCs transplantation. The number of neurons and neuroregeneration after injury were measured by Nissl's staining, immunofluorescence and western blot. The rat motor function was detected by Basso Beattie Bresnahan score and evoked potential. The myelin regeneration was detected by electron microscopy and toluidine blue staining. RESULTS AND CONCLUSION:Compared with the other groups, the Etanercept combined with TrkC-NSCs transplantation group had more survived anterior horn motor neurons at 28 days after injury, more myelin-encapsulated axons, higher Basso Beattie Bresnahan score, greater amplitude of the evoked potentials, and relatively shorter latency (alP < 0.05). These findings indicate that early application of tumor necrosis factor-α antagonist combined with TrkC-NSCs transplantation after spinal cord injury in rats can effectively promote myelin regeneration, axon regeneration, and further promote motor function recovery.

Objective To investigate the feasibility of mono-segment pedicle instrumentation (MSPI)in management of thoracolumbar fracture (AO classification,A1 and A3) by being compared with short-segment(two-segment) pedicle instrumentation(SSPI).Methods Overall 141 patients with tape A1 or A3 thoracolumbar fractures,aged from 20 to 60 years (average,40.5 years),were enrolled in this prospective study.According to a simple randomized method,35 patients with type A1 fracture and 41 patients with type A3fracture were treated with MSPI,while 26 with type A1 fracture and 39 with type A3 fracture were treated with SSPI.Low back outcome score (LBOS) and ASIA2000 were used to evaluate clinical outcome.Eighteenth month postoperatively was assigned as the last follow up period.Wedge index (WI) and sagittal index (SI) of the affected vertebrae on radiography were measured and compared preoperatively,one week postoperatively and at the final follow-up.Results All patients were followed up successfully.The blood loss and duration of operation of MSPI group were significantly less than that of SSPI group,respectively.However,there were no significant differences of clinical outcome between two groups.For type A1 fracture,correction rate and correction loss of WI in MSPI group were better than those in SSPI group.For type A3 fracture,there were no significant differences of correction rate and correction loss of WI and SI between MSPI group and SSPI group; however,the failure rate of MSPI group was significantly higher than that of SSPI group.Conclusion For type A1 and partial type A3 thoracolumbar fractures,MSPI can provide the same or better fixation with less blood loss and operative duration than SSPI.Since MSPI for type A3.2 thoracolumbar fracture has a higher failure rate,the surgical indication should be strictly controlled.

Objectives:To investigate the clinical outcome of Smiley face rod fixation system for lumbar isthmic spondylolysis.Methods:From January 2016 to June 2017,18 patients with isthmic spondylolysis were treated with smiley face screw-rod fixation system.There were 13 males and 5 females,with an average age of 28.2±3.2(25-32) years old.The average disease duration was 16.3±5.7(7-24) months.L5 isthmic spondylolysis was involved in all cases.All patients had been followed up at 3 months and 1 year after surgery.The preoperative and postoperative visual analogue scale(VAS) and Oswestry disability index(ODI) were compared.The X-ray and CT scan were evaluated to analyze the change of range of motion in the lumber spine and the bony fusion rate.Results:The mean operation time was 90.0±24.1 minutes.The average blood loss was 140±15ml.The average follow-up was 18.5±5.0 (12-24) months.The VAS at 3 months after operation was 3.0±1.2,and the ODI was (17.2±4.5)％ respectively,which showed significant differences compared with the preoperative ones[7.3±2.5 and (67.0±15.1)％](P＜0.05).The VAS and ODI at 1 year after operation were 1.0± 0.6 and (9.1±5.3)％,which showed significant differences compared with 3 months postoperation(P＜0.05).The range of motion between L5 and S1 was 13.1°±2.1° and the incidence of lumbar instability was 83.3％(15/18) preoperatively;it was 9.3°±1.6° and 11.1％(2/18) postoperatively,and there was statistic difference(P＜0.05).All patients achieved bone fusion in the isthmic defect 1 year after operation.Conclusions:The Smiley face rod fixation is a reliable treatment for lumbar spondylolysis with the advantage of minimal invasive,less nerve interference,and to restore normal anatomical structure,maintain the lumbar spine stability.