[Objective]To investigate the effect of dermatomal somatosensory evoked potential(DSEP) in diagnosing the damage of nerve root in lumbar spinal stenosis. [Method]Diagnostic test was deployed in this reseach.All experiment objects were divided into the case group and the control group.There were 47 cases in the case group.There were 14 males and 33 females with the mean age of 52.6 and the mean stature was 1.64 m.In the control group,there were 50 cases which include 26 males and 24 females with the mean age of 50.4 and the mean stature of 1.65 m.The DSEP P40 latency and P1-N1 amplitude of cutis plate in L4、5 and S1 segment were determined.The data of the case group were compared with those of control group and analyzed statistically.[Result]In the case group,the P40 latency of 91 segments prolonged obviously and P40 wave of 103 segments disappeared.Comparing the P40 latency and P1-N1 amplitude of 3 segments(L3、4、L4、5and L5S1) in two groups,the change was remarkable(P

[Objective]To analyze the relation of age and sex with the incidence of physical examinees with osteoporosis and low bone mass of vertebras.[Method]Quantitative CT(QCT) was used to examine and analyze the lumbar bone mineral density in 575 physical examinees.The data was analyzed by statistical software SAS 9.0.[Result]Bone mineral density(BMD)decreased with age after 50 years old.The occurrence rates of osteoporosis were 56.34% for females at 50-59 years,87.80% at 60-69 years,97.22% at 70-79 years and 100% at 80-89 years,25.44% for males at 50-59 years,50.64% at 60-69 years,66.66% at 70-79 years,and 90.91% at 80-89 years.[Conclusion]The incidence of osteoporosis is positively related with the age.The occurrence rate of osteoporosis increases with increasing age.It is obviously higher in females than in males.

Objective To investigate the clinical results of microsurgical free tissue transfers in pediatric reconstruction.Methods Between Janua~ 2004 and December 2010,twenty-seven free tissue transfers for reconstruction of various defects in 27 pediatric patients were performed.The average age at the time of reconstruction was 10.8 years(range:5-14 years).Fourteen patients were boys and 13 were girls.There were 5 tumor resection defects,sixteen posttraumatic defects and 6 burn contractures which consist of 19 fasciocutaneous flaps,six osteoseptocutaneous flaps and 2 muscle flaps.The mean operative time was 4 hours and 20 minutes.Results All flaps survived except 1 partial necrosis,with 96.3％ success rate.All patients were followed up 3 months to 4 years (mean,one and a half years).The appearance of the flaps was slightly overstaffed,but the color and texture were satisfactory.Conclusion Free tissue flap transfer is a safe,reliable,cost-and time-effective method for the reconstruction of various defects in children.

[Objective] To evaluate the clinical value of diagnosing osteoporosis with vertebra bone mineral density(BMD) by measurement with quantitative computed tomography (QCT) . [ Method] BMD in of lumbar vertebrae (L<,1～4>)were measured by QCT in 53 healthy middleaged persons or elderly persons (group A) and 68 osteoporosis patients ( groupB) . [Result] BMD in group A declined obviously as age increasing with significant differences (P<0. 01) . In group B,all 68 patients showed osteoporosis according to the diagnostic standard of BMD≤x -2. OSD. Sixty patients showed osteoporosis ifthe diagnostic standard was set to BMD ≤ x -2. 5SD. The BMD values of different age group was lower than the bone quantityblock values. [Conclusion] As a method for diagnosing osteoporosis, QCT has advantages of high sensitation, being precise,being reproducible and is easy for applying. It would be more practical and could decrease mis - diagnosing if the diagnosticstandard was BMD≤x-2.OSD.

Pedicle screw loosening and axial dislocation are main reasons for spinal internal fixation failure. Screw loosening and dislocation is caused by screw extraction force,and the screw withdrawl force is related to screw diameter,screw thread design,bone density,and operation skills. Withdrawl intensity is increased with screw diameter and length. Pedicle screw stability can be decreased by osteoporosis. For osteoporotic patients,it is difficult to increase screw diameter alone,so polymethyl methacrylate bone cement is used to enhance screw stability and anti-flexion intensity. However,polymerization heat may induce tissue injury,and long-term stay may produce toxicity and exhibit cancerogenesis. Novel additive materials with good biocompatibility such as hydroxyapatite and calcium phosphate bone cement are gradually replacing polymethyl methacrylate bone cement. In addition,screw entrance point,direction and exact location during screw implantation can decrease pullout strength reducation caused by screw re-twisting and improve screw extraction intensity and stability.

BACKGROUND: There are a lot of controversies regarding the choice of short versus long segment pedicle screw fixation for the treatment of isthmic spondylolisthesis and degenerative spondylolisthesis treatment. OBJECTIVE: To investigate clinical efficacy of short versus long segment pedicle screw fixation in treatment of lumbar spondylolisthesis.METHODS: A total of 146 spondylolisthesis patients were included in this study, 36 males and 110 females, aged 22-73 years at a mean of 53 years; disease duration was from 1 to 18 years at a mean of 5 years. These patients were treated with lumbar spinal window-opened decompression or laminectomy decompression, a short or long segment pedicle screw internal fixation, transverse interbody fusion.RESULTS AND CONCLUSION: Among 146 involved patients, 72 cases were treated with four pedicle screw fixation (short segments), while 74 cases with six pedicle screw fixation (long segments). Interbody graft was performed in 101 cases, while intertransverse fusion given in 45 cases. Totally 134 cases were followed up for postoperative 1.5-14 years. According to clinical grading standards of Steffee system, the clinical efficacy was assayed excellent in 74 cases, good in 41 cases, mild in 13 cases and poor in 6 cases, with good rate of 85.8%. 77 cases achieved a complete reduction, including 32 cases using a short segment fixation and 45 cases using a long segment fixation. 69 cases achieved partial reduction, including 40 cases using a short segment fixation and 29 cases using a long segment fixation. Pedicle screws ruptures were found in 13 screws of eight patients undergoing short segment fixation, while no pedicle screw fracture was found in long segment fixation. Choice of short or long segment for the fixation is based on the analysis of spondylolisthesis type, severity, duration of disease, emergence of adjacent segment disc degeneration and instability.

BACKGROUND:Detecting the serum levels of biochemical markers to assess bone fractures is simple, mini-invasive and specific. Thereafter, to predict bone nonunion by choosing an appropriate marker has become a hotspot.
OBJECTIVE:To establish an animal model of bone nonunion and explore the changing rules of the biochemical markers during the process of nonunion.
METHODS:Twenty New Zealand white rabbits aged 5-6 months were enrol ed and divided into two groups. In bone defect group, a 15-mm length of bone (including the periosteum) was removed from the left mid-radius, and the medul ary cavities were closed with bone wax. In bone fracture group, the mid-radius was fractured. X-ray examination was taken and blood samples were extracted preoperatively and at 2, 3, 4, 5, 6, 7, 8, 10, and 12 weeks after surgery. The serum levels of osteocalcin and bone-specific alkaline phosphatase (BSAP) as markers of bone formation, and C-terminal telopeptide of type I col agen (CTX), N-terminal telopeptide of type I col agen (NTX), and tartrate-resistant acid phosphatase 5b (TRACP 5b) as markers of bone resorption, were measured using biotin double-antibody sandwich ELISA.
RESULTS AND CONCLUSION:In the bone defect group, the bone metabolism was at a high level, suggesting that the early diagnosis of bone nonunion depends on several biochemical indicators. In the bone defect group, the serum level of CTX peaked at 5 weeks, and the serum levels of osteocalcin, BSAP and NTX decreased obviously at 4 or 5 weeks, while the serum TRACP 5b concentration did not change significantly, indicating that al above markers except TRACP 5b sensitively reflect the bone turnover in vivo. Further studies are needed to determine whether systematic monitoring of the biochemical markers can reflect the bone turnover effectively and can be used for the early diagnosis of nonunion in the rabbit model.

Objective To explore a reasonable and secure anesthesia induction in painless induced abortion.Methods 120 patients of painless induced abortion were randomly divided into six groups,control group was injected with Propofol 3.5mg/kg through vein,besides given Propofol 3.5mg/kg,other 5 groups were injected with ketamine 0.1mg/kg、0.2mg/kg、0.3mg/kg、0.4mg/kg、0.5mg/kg through vein respectively.The parameter of hemodynamics,effect of analgesia,time of unconsciousness,recovery time of consciousness,recovery time of orientation,incidence of respiratory depression,side effect,time of discharge from hospital were observed.Results The recorded time and incidence of side effect have statistical significance between group of ketamine 0.5mg/kg and group of ketamine 0.3mg/ks(P<0.05);effect of analgesia have statistical significance between group of ketamine 0.3mg/kg、0.4mg/kg、0.5mg/kg and control group.Conclusion Ketamine 0.3mg/kg combined with Propofol is an ideal choice of painless induced abortion.

A total of 64 patients with lumbar spondylolisthesis were enrolled from Department of Bone Surgery in the People's Hospital of Haian Province between January 2002 and December 2007, including 19 males and 45 females. They aged 26-73 years with a mean of 48.5 years. Their disease course was 1-15 years with a mean of 4 years. All patients complained about the repeated low back pain accompanied with lower limb radiating pain and intermittent claudication (50-300 m). Fifty-nine patients suffered from lumbar spondylolysis, including L3 Ⅰ degree in 3 cases, L4 Ⅰ degree in 31 cases,L4, Ⅱ degree in 13 cases, Ls Ⅰdegree in 9 cases and L5 Ⅱ degree in 3 cases. The remaining 5 cases were present with lumbar degenerative pseudo-spondylolysis. All patients were processed into whole laminectomy for decompression or vertebral canal decompression by fenestration, domestic vertebral internal fixation, reduction and interbody fusion. Fifty-five patients were followed up for an average of 3.1 years whereas 9 patients were lost. According to Steffee clinical effect grading, the curative effect was evaluated as excellent in 28 cases and good in 19 cases, the rate of excellence and good accounted for 85.5%. Within one week following bone graft, all patients were rechecked with X-ray plain film, 28 of them had shown complete reduction and 36 cases were present with part reduction. The fusion rate of interbody graft was 100%. These findings demonstrated that vertebral internal fixation system possesses a simple structure, convenient operation and solid fixation, resets the slipped vertebral body and significantly increases the fusion rate of vertebral graft.

BACKGROUND:Currently, X-ray examination is mainly used for diagnosis of nonunion. However, this method that relies only on the clinician’s experience and degree of calus mineralization has less accuracy because it is vulnerable to projection, processing conditions and subjective factors. OBJECTIVE:To establish an animal model of nonunion and to detect the variation of biochemical markers and bone mineral density. METHODS: Twenty New Zealand white rabbits were randomly divided into two groups, and bone defect and fracture models were made in the midshaft of the forearm radius, respectively. X-ray examination of the forearm, quantitative CT measurement of bone mineral density and serological test were carried out before and at 2, 3, 4, 5, 6, 7, 8, 10, 12 weeks after surgery.RESULTS AND CONCLUSION:Postoperative X-ray films showed that the in the bone defect group, a little calus formed in three rabbits at 2 weeks, the calus formed stably at 5 weeks, but there was stil no healing at 8 weeks; in the fracture group, the fracture line was blurred at 2 weeks and a large number of caluses formed at 6-8 weeks. Compared with the fracture group, the value of bone mineral density in the bone defect group began to decrease significantly at 5 weeks after surgery. Results from the serological test showed that in the bone defect group, the activity of bone-specific alkaline phosphatase increased after surgery, reached peak at 4 weeks, began to decrease at 5 weeks and became stable at 6 weeks; the activity of tartrate-resistant acid phosphatase 5b increased after surgery, peaked at 4 weeks, then decreased and stabilized basicaly; the expression of N-terminal telopeptide of type I colagen decreased significantly at 5 weeks after surgery and became stable at 6 weeks. These findings indicate that the systematic monitoring of changes in bone mineral density and biochemical indicators such as bone-specific alkaline phosphatase, tartrate-resistant acid phosphatase 5b and type I colagen N-terminal telopeptides may help to reflect the early progress of rabbit nonunion.