The early treatment principles of spinal cord injury (SCI) included early drug using, early surgery and early rehabilitation.The literatures on how to use drug early and how to control the time for SCI before surgery were reviewed.

Objective:To evaluate the feasibility and clinical efficacy of the treatment of lumbar spine steno-sis by modified unilateral approach for bilateral decompression under microendoscope.Method:217 cases with degenerative lumbar spine stenosis from September 2003 to December 2008 were treated by modified unilater-al approach for bilateral decompression of central spinal canal and nerve root canal under microendoscope.A-mong them laminectomy of one segment was done in 163 cases,two segments were done in 54 cases.After surgery,the routine radiograph were carried out and the Nakai criterion was used for assessment.Result:The mean operative time was 48±13min (range,25 to 95min),the average blood loss was 37±9ml (range,25 to 180ml),the average skin incision length was 2.2±0.2cm(1.8 to 2.4cm).2 cases had dural matter tearing,which healed after filling with gelatin foam and 2 weeks bed rest,after that no cerebrospinal fluid leakage was noted after surgery.Mislocation was noted in 1 case.No nerve inury and postoperative infection oceurred.Postoperative CT scan demonstrated complete decompression of the central spinal canal and nerve root canal.All patients were followed-up for an average of 14 months (range,3 months to 24 months).The Nakai criterion at final follow-up showed clinical excellent in 134 cases,good in 63 cases,fair in 16 cases and worse in 4 cases, with the excellent and good rate of 90.8%.No lumbar spine instability was noted.Conclusion:Treatment of de-generative lumbar spine stenosis by modified unilateral approach for bilateral decompression under mieroendo-scope has the merit of minimal invasive,less complications and reliable therapeutical effect.

Objective To investigate the anti-chronic stress effect of bone marrow mesenchymal stem cell (BMSCs) transplantation in rats with spinal cord injury.Methods Forty-eight adult SD rats were divided into control group,model group and treatment group according to the random number table,with 16 rats each.In model and treatment groups,lower thoracic (T10) spinal cord injury were constructed using the modified Allen's method.In control group,only laminectomy was performed.After 7 days,100 μl Hank's buffer suspension containing 1.0 × 106 BMSCs was injected into the subarachnoid space of L4-5 intervertebral space of rats in control group and treatment group.While in model group,only the equal volume of Hank's buffer was used.Basso-Beattie-Bresnahan (BBB) scale was performed to evaluate hindlimb motor function in rats.At postoperative 14 and 28 days,blood samples were collected to measure adrenocorticotropic hormone (ACTH),norepinephrine (NE),epinephrine (E) and corticosterone (CORT) using the ELISA method;brains were harvested for the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor proteins GluR1 and GluR2 immunohistochemical staining.Results After injury,BBB scores in model and treatment groups were similar,but both were lower than that in control group (P ＜ 0.05).After BMSCs transplantation,BBB score in treatment group [21 d:(9.85 ± 0.82)points and 28 d:(11.23 ±0.68)points] improved continuously compared to model group [21 d:(8.42 ± 0.39) points and 28 d:(8.84 ± 0.25) points],but all were lower than that in control group [(21.00 ±0.00)points,P ＜0.05].ACTH contents in model and treatment groups at 14d [(104.80±6.16) and (98.50 ± 4.07) pg/ml] and 28 d [(101.40±2.33) and (96.50± 2.28) pg/ml] were higher than those in control group [(90.40 ± 1 1.36) and (83.20 ± 5.22) pg/ml] (P ＜ 0.05).CORT contents in model and treatment groups [(44.40 ± 1.44) and (43.30 ± 1.17) ng/ml] was lower than that in control group [(48.20 ± 2.27) ng/ml] at 14 d,but were found to be elevated [(70.40 ± 1.90) and (61.40 ± 1.83) ng/ml] compared to control group [(46.40 ± 1.49) ng/ml] at 28 d (P ＜ 0.05).Meanwhile,the CORT content in treatment group was lower than that in model group (P ＜ 0.05).Changes in NE and E contents among the groups were similar with ACTH.Immunohistochemical staining suggested the amounts of GluR1 and GluR2 positive cells in treatment group lowered compared to control group (P ＜ 0.05),but increased in model group compared to control group (P ＜ 0.05).Conclusion BMSCs transplantation can improve the hindlimb motor function,contribute to reducing the secretion of stress-related hormones ACTH,CORT,NE and E,and down-regulate the expression of AMPA receptor proteins GluR1 and GluR2 in rats with spinal cord injury,suggesting a potential role in antichronic stress.

Objective To investigate the effect of metformin on the osteogenic differentiation of human mesenchymal stem cells exposed to PMMA particles. Methods Human placental mesenchymal stem cells were iso-lated and cultured in vitro. The effect of metformin with different concentrations on cell viability was determined by CCK8 assay. The effect of metformin on the mRNA expression of osteogenic genes was detected by using real-time RT-PCR. Calcified nodules were stained by alizarin S. The effect of metformin on the expression of eNOS was also detected by using real-time RT-PCR. Results PMMA particles could inhibit the viability of mesenchymal stem cells. Metformin(0.05 mmol/L)could promote the viability of mesenchymal stem cells exposed to PMMA particles. Metformin(0.05 mmol/L)could increase the expression of osteogenic genes,including OCN,RNUX2,and ALP, in human mesenchymal stem cells exposed to PMMA particles. The calcium deposit was also increased after metfor-min treatment. Results of real-time RT-PCR showed that metformin could increase the expression of eNOS in human mesenchymal stem cells exposed to PMMA particles. Conclusions Metformin can increase the osteogenic differentiation of human mesenchymal stem cells exposed to PMMA particles,partially by inducing eNOS expression.

[Objective]To develop an animal pulmonary cement embolism model,by which the effect of polymethylmethacrylate(PMMA),calcium phosphate cement(CPC) and silk fibroin/calcium phosphate cement composite(SF/CPC) on the hemodynamic change,respiratory function and the antithrombin activity were measured after the pulmonary embolism caused by cement injection.The efficiency of SF reducing the risk of cardiovascular complication was evaluated.[Method]Twenty-four pigs were assigned to 3 groups randomly,with 8 pigs in each group.After general anesthesia,animals were endotracheal intubated and mechanically ventilated by a respirator.The pulmonary trunk was exposed via sternotomy and each kind of cement was injected into the main pulmonary artery.Hemodynamic parameters were continuously monitored.Blood samples were drawn at certain time points for blood gases analyzing and measurement of AT Ⅲ.Postmortem lungs were subject to computer tomography(CT) examination along with three-dimensional reconstructions of cement casts.[Result]The injection of CPC caused severe pulmonary hypertension and arterial hypotension,with a maximum elevation of 20.93?5.04 mmHg in PAP(20 min post-injection) and a maximum decrease of-26.59?6.8 mmHg in MABP(50 min post-injection).The changes in SF/CPC group were relatively slighter,which is similar with PMMA group,having a statistically significant difference from CPC groups(P

Objective To conduct biomechanical study and three dimensional finite element analysis on lumbar spondylolysis and spondylolisthesis treated with single vertebra reduction and fixation system(LSRF), and to evaluate the long term outcome of isthmic spondylolisthesis treated with direct repair and fixation with LSRF. Methods Biomechanical characteristics of LSRF was tested, and three dimensional finite element model of lumbar spondylolysis and isthmic spondylolisthesis was established, the stress of lumbar in spondylolisthesis was observed after fixation and reduction. Thirty two patients with spondylolysis and isthmic spondylolisthesis were treated with direct repair and fixation with LSRF designed by the authors from 1992 to 1995. Eighteen cases had spondylolysis, and the others accompanied with spondylolisthesis. The patients age was 28-46 years, with an average of 36.4 years. Results The biomechanical study and three dimensional finite element analysis showed that LSRF has good ability in reduction and rigid fixation. All patients were followed up for an average of 5.6 years. The latest radiographs showed that bony union occurred in 29 cases. There was no breakage and pullout of screws except dislocation of hook in 2 patients. By Henderson standard, the result was excellent in 22, good in 6, fair in 2, poor in 2. Conclusion LSRF has stronger fixation strength and higher fusion rate. Direct repair and fixation with LSRF is a good procedure for younger and middle aged patients with spondylolysis and isthmic spondylolisthesis.

Objective To evaluate the efficacy and safety of balloon kyphoplasty in the treatment of painful osteoporotic vertebral compressive fractures. Methods From May 2000 to June 2002, 56 consecutive procedures were performed in 30 patients of painful osteoporotic vertebral compressive fractures with intact posterior vertebral body wall. Each procedure includes bilateral insertion of inflatable balloon, fracture reduction and fulfilled with bone cement. Preoperative and postoperative symptom levels, complications and radiographic findings were recorded and analyzed. Results All 30 patients tolerated the procedure well with immediate relief of their back pain in 48 hours. The mean loss of the anterior and mid vertebral body heights were (13.6?2.3) mm, (9.2?1.4) mm preoperatively and (4.7?1.5) mm, (3.4?1.1) mm postoperatively. The mean kyphosis was improved from 23.4??5.2? to 9.2??4.7?. Cement leakage and cerebrospinal fluid leakage occurred at one level respectively and resulted in no clinical symptoms, no other complication was found. Conclusion As a promising minimally invasive surgery, balloon kyphoplasty can provide early improvement of pain and function as well as spinal alignment in treatment of painful osteoporotic compressive fractures.

Objective To investigate the clinical results of bilateral transpedicular kyphoplasty for the osteoporotic vertebral compression fractures with single balloon. Methods From March 2002 to February 2004, percutaneous bilateral transpedicular kyphoplasty with single balloon was performed in 15 patients, who presented with painful vertebral compression fractures. In the group, there were 6 vertebrae of 6 males and 11 vertebrae of 9 females, and the average age of the patients was 70.5 years with a range of 62 to 82 years. 17 osteoporotic vertebral compression fractures, which involved 8 T12, 7 L1, 1 T8 and 1 T11, were treated. Osteoporosis was identified in all cases by the measurement of lumbar bone mineral density (BMD) and the evaluation of radiographs. The average BMD was 0.603 g/cm2. CT scan showed the posterior vertebral wall intact in all patients, and MRI displayed low signal on T1WI and high signal on T2WI of the vertebral fractures. Results All patients experienced dramatic pain relief after the procedures. The mean pain score (VAS) decreased significantly from 8.3 preoperatively to 2.1 after operation. The mean vertebral body height restoration was 54.2%?34.1% on the anterior border, 60.5%?35.4% in the middle portion, and 40.7%?32.3% on the posterior border respectively. And the sagittal alignment was improved significantly, as the average correction of the Cobb's angle reached 9.5?. No cement leakage was found on X-ray, except one with less cement at the anterior vertebral edge, but no clinical symptom occurred. All the patients were available at the final follow-up, the mean period was 10.5 months (range, 2-48 months). Conclusion Bilateral transpedicular kyphoplasty with single balloon not only can provide effective pain relief and vertebral height restoration, but also can improve the sagittal alignment significantly. Its clinical outcome was satisfactory.

0.05). Conclusion The study of the characteristic of track of percutaneous transpedicular puncture is good for the safe procdure under image guidance. The standard track is safe for transpedicular or parapedicular puncture. The percutaneous transpedicular puncturing sites can be located according to the spinous process.

Objective To study the method of isolating and culturing stem cells from rat adipose tissue and to determine if adipose-derived stem cells(ADSCs)harvest from rat could differentiate into osteogenic and chondrogenic in vitro.Methods ADSCs were isolated from rat inguinal fat pads after extensive washing with phosphate-derived saline and digesting with collagenase.After primary culture in control medium and expanded to two passages,the cells were incubated in either an osteogenic medium or an chondrogenic medium for 2-4 weeks to induce osteogenesis and chondrogenesis,respectively.Evidences of Osteogenic differentiation,were detected by a ALP solution,and while chondrogenic differentiation was confirmed using the histologic Alcian blue staining at acidic pH.Expressions of osteocyte and chondrocyte specific genes were confirmed by RT-PCR.Results ADSCs can be isolated from rat adipose tissue and,expanded rapidly.It exhibited a heterogeneous population of fibroblast like cells morphologically.ADSCs induced to osteogenesis were stained positively for alkaline phosphatase activity after 2 weeks and formed mineralized nodular structures,as conformed by Von kossa staining.Expression of osteocyte specific genes,such as ALP,osteopontin,osteocalcin,was detected.ALP and osteopontin,were expressed constitutively in osteogenic medium after 2 and 4 weeks of culture.Expression of osteocalcin,was induced by osteogenic growth factors at 4 weeks.Induced to chondrogenesis cells were positive of Alcian blue staining under acidic conditions and expression of aggrecan and typeⅡ/Ⅹ collagen genes.Aggrecan and typeⅡcollagen genes were abundant after 2 weeks in chondrogenic medium.TypeⅩ collagen gene was detected at 4 weeks.Conclusion Adipose-derived stem cells can be isolated from rat adipose tissue.Their biological characteristics are similar with mesenchymal stem cells(MSCs),and have the potential to differentiate into osteogenic and chondrogenic lineage.It may be an idea source of ADSCs for tissue engineering.