Objective To compare the clinical efficacy of anteroposterior approach (APA) versus anterior approach (AA) for decompression,fusion and fixation for single-level unstable thoracolumbar vertebrae fractures concomitant with incomplete neurologic symptoms and injury to posterior ligament complex (PLC).Methods From February 2006 to June 2012,55 patients were treated for single-level unstable thoracolumbar vertebrae fractures.Of them,27 were treated by only anterior decompression and lateral screw-rod instrumentation and 28 by anterior decompression and fusion combined with open posterior pedicle fixation of one to two segments above and below the fracture position.The 2 groups were compared at postoperative 3 and 12 months in terms of visual analogue scale (VAS),overall score of short-form health survey (SF-36),Japanese Orthopaedics Association (JOA) score of lower back,Oswestry disability index (ODI),loss ratio of anterior margin of vertebral height,endplate angle of kyphotic deformity of superior-inferior adjacent vertebrae,wedge angle of fractured vertebra via radiographic measurement and canal compromise rate.The neurologic functional recovery was analyzed using the American Spine Injury Association (ASIA) evaluation system at postoperative 12 months.Results There were no significant differcnces in operative time,amount of blood loss or postoperative drainage between the 2 groups (P ＞ 0.05).At postoperative 3 months,the VAS and JOA scores in the APA group were significantly better than those in the AA group (P ＜ 0.05).At 12 months after surgery,the VAS,kyphotic angle of adjacent vertebra,wedge angle of fractured vertebra and the ASIA improvements in the APA group were significantly better than those in the AA group (P ＜ 0.05).There were no significant differences between the 2 groups in the other indexes at postoperative 3 or 12 months (P ＞ 0.05).All the comparative indexes were significantly improved than the preoperative values in all the patients in the 2 groups at both 3 and 12 months (P ＜ 0.05).Conclusions Compared with the merely anterior approach,the combined antero-posterior approach may have advantages of better immediate and persistent reduction,steadily rebuilding fractured alignment,continuously maintaining injured biomechanical stability,and obviously improving neurological function.As the antero-posterior approach allows for combination of posterior auxiliary reduction and fixation with anterior definitive support and decompression,it may lead to a safe and effective treatment of unstable single-level thoracolumbar fracture concomitant with incomplete neurologic and PLC impairments.

Objective To assess the efficacy and safety of tranexamic acid (TXA) in decreasing operative blood loss and the need for transfusion during posterior spinal fusion for the treatment of idiopathic scoliosis in adolescents. Methods A retrospective comparative analysis of 93 consecutive adolescents undergoing posterior spinal fusion procedures was per?formed. Patients were divided into treatment group (TXA, n=43) and control group (n=50). Clinical indicators were compared in operation and after operation between two groups. Results There was significantly less operative blood loss (703±176) mL in TXA group than that of control group (1143±389) mL. And post operation flow was also lower in TXA group than that of control group [(145 ± 75)mL vs (278 ± 95) mL, P<0.001)]. Autologous blood recovery in patients was lower in TXA group than that of control group [(241.0±109.1) mL vs (372.7±123.0) mL, P<0.001). There were no major intraoperative complica?tions in two groups. There was no blood transfusion in TXA group, and there was 1 case with 400 mL blood transfusion in con?trol group. Conclusion TXA treatment can decrease blood loss and blood transfusion and not increase intraoperative and postoperative complications in surgery of posterior spinal fusion of adolescent idiopathic scoliosis.

Objective To explore the function and mechanisms of Wnt7a in bone msenchymal stem cells (BMSCs) osteogenic differentiation.Methods BMSCs were isolated and cultured.After transfection of siRNA-Wnt7a and mock in BMSCs and induction by osteogenic medium for 3 d,Western Blot were employed to detect the silencing effect of siRNA-Wnt7a.Then the effect of silencing Wnt7a on the expression of osteocyte marker osteocalcin and osteogenesis regulator protein Runx2 were detected by Western Blot after culture by osteogenic medium for 10 d.Finally,Alizarin S Red staining was used to detect the effect of silencing siRNA-Wnt7a on osteogenesis after culture by osteogenic medium for 2 weeks.Results The silencing effect of siRNA-Wnt7a was confirmed by Western Blot after transfection of oligocleotides siRNA-Wnt7a and mock into mesechymal stem cells.The silencing Wnt7a decreased the expression of osteocalcin and Runx2 after culture by osteogenic medium for 10 d.Alizarin S red staining results showed that silencing Wnt7a blocked bone differentiation.Conclusions The results demonstrated that Wnt7a could promot osteocyte marker osteocalcin expression by upregulating osteogenesis regulator protein Runx2 expression,which played a key role in BMSCs osteogenic differentiation.

Objective To observe the diffusion and aggregation of the microtubule associated protein tau(MAPT)modu?lated by phosphatase and tensin homolog deleted on chromosome ten(PTEN)during the nerve cell differentiation by human bone marrow stem cells(BMSC)in vitro, and to analyse the signification. Methods Adult bone marrow stem cells were iso?lated and induced into nerve-like cells by some cytokines in vitro. The mRNA expression of MAPT was detected by semi-quantitative RT-PCR and Western blot assay. The patterns of diffusion and aggregation of the MAPT association of the actin were indicated by Phalloidin-fluoresceineisothioeyanate (FITC) and immunofluorescence (IF) cyto-chemistry, and observed by the laser-confocal microscopy. Results The MAPT mRNA levels were 0.24 ± 0.04 and 0.52 ± 0.04 at 1 week and 2 weeks after the induction,which were significantly higher compared with those of BMSC (0.04 ± 0.02) after the induction (P<0.05). The MAPT protein levels were 0.18 ± 0.03 and 0.44 ± 0.05 at 1 week and 2 weeks after the induction, which were significantly higher compared those of BMSC (0.06 ± 0.04, P<0.05). The distribution patterns of MAPT were changed from the diffusion to the aggregation in cells after treatment by BPV. The nerve-like cells appeared the characteristic of po?larization. Conclusion When the nerve cells derived from bone marrow stem cells obtain the mature differentiation, PTEN may possess the ability of modulating the diffusion and aggregation of MAPT in vitro, also may provide a kind of material ba?sis for the growth of the nerve axon.

Objective To introduce a modified replantation for thumb rotating avulsion amputation,and to evaluate its short term clinical outcome.Methods From January 2007 to July 2009,7 patients with thumb rotating avulsion amputation underwent replantation,including 6 males and 1 female,aged from 21 to 47 years (average,28.3 years).The amputation level of each thumb was metacarpophalangeal joint.During operation,fusion of metacarpophalangeal joint was performed according to injury degree of soft tissue; interphalangeal joint of the thumb was fixed in 15 degrees of flexion by sewing flexor pollicis longus muscle tendon and extensor pollicis longus muscle tendon to tendon sheath or soft tissue; the superficial vein harvested from ipsilateral forearm was used to bridge the dorsal carpal branch of radial artery and the ulnar palmacollateral artery of the thumb; direct anastomoses of dorsal veins were performed in 6 cases and venous transplantation in 1 case; and bilateral nerves were transferred to the back of the first metacarpal and anastomosed to the superficial branch of the radial nerve.Results All 7 replanted thumbs survived completely.Arterial crisis occurred in 1 case after operation,which was cured after operative and medication treatment.The follow-up period ranged from 3 to 24 months.The appearance and opposition function of replanted thumbs were satisfactory and the sensation of fingertip recovered to S4 in 4 cases and to S3 in 3 cases.The two point discrimination ranged from 8 to 12 mm.Conclusion Because bridging the dorsal carpal branch of radial artery and the ulnar palmar collateral artery of the thumb with a superficial vein harvested from ipsilateral forearm to reconstruct blood supply of the thumb is available and easy to be performed,this modified replantation is an ideal way to repair thumb rotating avulsion amputation.

Objective To study the protective effects of ischemic postconditioning and preconditioning against ischemic reperfusion injury of skeletal muscle.Methods According to different treatment methods on ischemia-reperfusion injury,forty Wistar rats were divided into I/R group,IPost group,IPC group,IPC + IPost group,control group.Using a rat amputation-like model,Wistar rats underwent temporary amputation at the level of the femur,excluding the femoral vessels.By measuring MDA,MPO,the extent of skeletal muscle infarction,protective effects of postconditioning and preconditioning,postconditioning combined with preconditioning were observed.Results In the Ipost group,IPC group,IPC + Ipost group,MDA and MPO at one hour of reperfusion and extent of muscle infarction at 6 hour of reperfusion was lower than group IR (P ＜ 0.05).In the Ipost group,MDA,MPO and extent of muscle infarction was similar to group IPC + Ipost; In the Ipost group,MDA and MPO was lower than group IPC,extent of muscle infarction was similar to group IPC.Conclusion Ischemic postconditioning at the beginning of reperfusion can protect skeletal muscle against ischemic reperfusion injury.Preconditioning also protect skeletal muscle against ischemic reperfusion injury,but preconditioning combined with postconditioning don't offer additional benefit over preconditioning or postconditioning alone.

Objective To explore the survival rate and early-term effects of sensory reconstruction of the modified first dorsal metacarpal artery (FDMCA) flap in treatment of thumb distal soft tissue defect.Methods From March 2004 to October 2007, 65 patients with soft tissue defects of the thumb underwent the FDMCA flap in our department. Forty-nine cases with complete data were included in the study. There were 37 males and 12 females, with an average age of 32 years (ranged, 18-65 years). The conventional surgical methods were used in 18 cases while the improved surgical methods were in 31 cases. The distal necrosis, the vascular crisis rate and the sensory recovery were recorded. Results The mean follow-up period was 2 years (ranged, 20 months to 3 years). Forty-six flaps survived completely. Vascular crisis occurred in five cases harvested by the conventional methods. Eventually, three of them had a partial distal necrosis.Improved FDMCA flap survived well in all 31 patients. Flaps in these patients with nerve anastomosis restored satisfied sense and all sense were located in the thumb. Eighteen cases of nerve transfer group had different levels of mixed feelings (33%) or ectopic sensory (62%). Sense was located in the thumb completely in 1 case. Conclusion The modified FDMCA flap significantly increased the survival rate. Neurorrhaphy could make the sense of the flap locate in the thumb; however it had not been proved that its impact on the recovery of two-point discrimination and stereognosis.

Objective To investigate the biomechanics of the tissue engineered tendons which use the embryonic tendon cells as the seed-cells and the silk as the scaffolds. Methods Two groups were set up with one as the group with tenocytes and the other as the group without tenocytes. Tissue engineered tendons were taken out at 2-week, 4-week, 6-week, 8-week post-operation, with 20 samples per-group each time. The values of biomechanics were measured and analyzed using the software SPSS 13.0. Results The biomechanical properties of the tissue engineered tendons in the group with tenocytes were significantly better than those in the group without tenocytes (P<0.05). In the group with tenocytes, the vitodynamics results got better with the increase of implantation time (P<0.05) except for the results of 8-week post--operation(P>0.05). But in the group without tenocytes, only the results of that from 8-week post-operation were of significant significance (P<0.05). Conclusion The results presented in the current study demonstrated that silk could stick tenocytes well, hold the characteristics of great resistance to draw after adhesion of tenocytes, and formed the tissue engineered tendon gradually in chickens, suggesting its potential application in the treatment of the defect of tendon.

[Objective]To explore the operative techniques of open reduction and internal fixation of displaced radial head fractures in adults. [Methods]Twenty-six cases of radial head fractures had been treated with open reduction and internal fixation. According to Mason classification, 16 fractures were type II, 6 were type III and 4 were type IV. Operative exposures of radial head were performed through the Kocher approach in 22 cases, and through a midline posterior skin incision in 4 cases in order to repair concomitant fracture of proximal ulna. After being reduced, fractures of radial head were fixed with mini-fragment plate and screw which were placed in "safe zone" not to impinge on the proximal radioulnar joint with forearm rotation.[Results]At a mean follow-up of 32 months, all fractures had united. There was no patient who suffered from wound infection or injury to posterior interosseous nerve. According to the Broberg and Morrey functional elbow index, the outcome were excellent in 17 patients, good in 9.[Conclusion]Open reduction and internal fixation of displaced radial head fractures may get satisfying outcomes, with successful performing of the requirements below: (1) sustaining lateral ulnar collateral ligament; (2) avoiding injury to posterior inerosseous nerve; (3) getting anatomic reduction; (4) stably fixing fractures without impinging on joint.

[Objective]To investigate the possibility of construction of tendon defect with allogeneic embryonic tenocyte combined with silk.[Method]Roman hens were randomly divided into 2 groups: construction with allogeneic tenocyte combined with silk as cell group,construction with silk alone as non-cell group.The pathology,vitodynamics and elongation were compared between 2 groups at 2,4,6,and 8 weeks postoperatively.[Result]Collagen production and vitodynamics in cell group were better than those in non-cell group significantly(P