Objective To evaluate the efficacy of different doses of dezocine for decreasing the minimum alveolar concentration (MAC) of desflurane.Methods ASA physical status Ⅰ or Ⅱ patients of both sexes,aged 50-70 yr,undergoing elective lower abdominal surgery performed under general anesthesia,were divided into 4 groups:control group (group C)and different doses of dezocine groups (D1,D2 and D3 groups).Before induction of anesthesia,in D1,D2 and D3 groups,dezocine 0.050,0.075 and 0.100 mg/kg were intravenously infused,respectively,while in group C,the equal volume of normal saline was given instead of dezocine.The adverse reactions were observed.Propofol 3 mg/kg was given for induction of anesthesia 15 min later until patient' s consciousness and spontaneous respiration disappeared.Laryngeal mask airway was inserted and the patients were mechanically ventilated.Up-and-down sequential allocation was used to determine the MAC of desflurane during maintenance of anesthesia.The end-tidal concentration of desflurane was set at 8.0％ and maintained at this level for at least 5 min before skin incision in the first patient.Each time the concentration of desflurane increased/decreased in the next patient depending on whether or not the body movement developed.The ratio between the two successive concentrations was 0.9.The point between the positive response and negative response served as a cross-over point.After at least 7 independent cross-over points were observed in each group,the experiment was stopped.The MAC and 95 ％ confidence interval of desflurane were calculated.Results No adverse reactions developed in each group.The MAC of desflurane was significantly lower in D1-3 groups than in group C,in groups D2.3 than in group D1,and in group D3 than in group D2.Conclusion Dezocine 0.100 mg/kg injected intravenously at 15 min before induction of anesthesia provides a better efficacy for decreasing the MAC of desflurane in the patients.

Objective To evatluate the effect of dexmedetomidine on intraoperative wake-up test during cerebral functional area operation performed under combined iv propofol-remifentanil anesthesia.Methods Twenty-seven ASA Ⅰ or Ⅱ patients (both sexes) aged 17-43 yr with a body mass index of 20-24 kg/m2 undergoing op-eration on cerebral functional area during which intraoperative wake-up test was performed were randomly divided into control group (group C,n =13) and dexmedetomidine group (group D,n =14).Anesthesia was induced with midazolam,sufentanil,etomidate and rocuronium and maintained with TCl of propofol (Cp =3-5 μg/ml) and remifentanil (Ce =2-6 ng/ml).BIS value was maintained at 55-65.In group D after dura of brain was opened,a loading dose of dexmedetomidine 0.3 μg/kg was administered iv over 15 min followed by continuous iv infusion at 0.2 μg· kg-1 · h-1 while TCI of propofol and remifentanil were suspended.In group C after opening of dura,Cp of propofol TCI was reduced to 0.5 μg/ml and Ce of remifentanil to 0.5 ng/ml.The wake-up time and development of hypertension,tachycardia,headache,dysphoria,delirium and awareness were recorded.Results All patients were successfully awakened.There was no significant difference in wake-up time between the 2 groups (P ＞0.05).The incidences of hypertension,tachycardia,headache and awareness were significantly lower in group D than in group C (P ＜ 0.05).Conclusion Dexmedetomidine does not affect intraoperative wake-up time during operation on cerebral functional area performed under iv propofol-remifentanil anesthesia,but can significantly reduce the incidence of adverse effects.

Objective To investigate the effects of different concentrations of dexmedetomidine on the expression of Toll-like receptor 4 (TLR4) mRNA in rat peripheral blood monocytes exposed to lipopolysaccharide ( LPS ). Methods Peripheral blood monocytes isolated from male Wistar rats were seeded in 24-well plate in RPMI 1640 liquid culture medium in CO2 incubator at 37 ℃ and 5% CO2 for 2 h, and were randomly divided into 5 groups ( n = 8 each): group A negative control; group B was exposed to LPS 1 μg/ml and C, D and E groups were exposed to LPS 1 μg/ml + dexmetomidine 0.5, 5.0 and 50.0 ng/ml respectively. The monocytes were then incubated for 24 h. The concentrations of TNF-α, IL-1β and IL-6 in the supernatant of the cultured monocytes were detected by ELISA. The expression of TLR4 mRNA in the monocytes was detected by RT-PCR.Results Exposure to LPS significantly increased the expression of TLR4 mRNA and the concentrations of TNF-α, IL-1β and IL -6 in group B as compared with group A ( P ＜ 0.01 ). Dexmedetomidine attenuated the LPS-induced increase in the expression of TLR 4 mRNA and the concentrations of TNF-α, IL-1β and IL-6 in a dose-dependent manner ( P ＜0.05or 0.01 ). Conclusion Dexmedetomidine can inhibit the synthesis of TLR4 and inhibit the secretion and dilivery of TNF-α, IL-1β and IL-6 by down-regulating the gene expression of TLR4 in rat peripheral blood monocytes exposed to LPS.

Objective To analyze the clinical results of mini-incision Schwab grade 4 osteotomy combined with percutaneous pedicle screw fixation for old thoracolumbar compression fractures combined with kyphosis deformity.Methods A retrospective case series study was made on 14 patients with old thoracolumbar compression fractures combined with thoracolumbar kyphosis undergone mini-incision Schwab grade 4 osteotomy plus percutaneous pedicle screw fixation from January 2014 to May 2015.There were 5 males and 9 females,with mean age of 64.5 years (range,58-70 years).The period between injury and surgery ranged between 6 and 14 months (mean,8.6 months).At the time of surgery,the fracture was already healed in 10 patients,while non-healing was found in other 4 patients.Preoperative visual analogue score (VAS) of back pain was (8.5 ± 1.1)points (range,6.5-10 points).Three patients were associated with neurological dysfunction [American Spinal Injury Association (ASIA) grade D].Apex of kyphosis located at T12 in 6 patients and at L1 in 8 patients.Preoperative kyphosis Cobb angle was (42.5 ± 6.0)° (range,39.5°-47.2°).Operation time,blood loss,perioperative complications,postoperative kyphosis Cobb angle,bone fusion,state of implants,neurological function and VAS were determined.Results Operation time was (280 ± 50) min,and blood loss was (110 ±70)ml.No segmental vessels injury,neurological deficit or dural disruption occurred during the surgery and after surgery.Compared to the preoperative detection,kyphosis Cobb angle was improved to (9.3 ±1.7) ° (range,6.2°-12.1 °) after operation (P ＜ 0.05),with the correction rate of 78.1％.Postoperative CT showed 7 screws (6.3％,7/112) were grade 1 screws.The follow-up was lasted for mean 25.2 months (range,14-28.9 months).At the latest follow-up,the kyphosis Cobb angle was (9.6 ±4.1)°(range,6.0°-13.1°),revealing no correction loss.Interbody bone fusion was good,with no instrumentation-related complications observed.Three patients with neurological dysfunction (ASIA grade D) were recovered to ASIA grade E.Compared to the preoperative detection,back pain was improved with the VAS of (2.6 ± 1.0) points at the latest follow-up (P ＜ 0.05).Conclusion Mini-incision Schwab grade 4 osteotomy combined with percutaneous pedicle screw fixation of old thoracolumbar compression fractures with kyphosis deformity can attain satisfactory and reliable efficacy and bone fusion,with low incidence of complications.

Objective To compare the clinical outcome of minimally invasive transforaminal lumbar interbody fusion (M-TLIF) and Wiltse-approach TLIF (W-TLIF) in treating single-level degenerative lumbar disease.Methods A retrospective review was performed on the 57 patients with single-level degenerative lumbar disorder managed via M-TLIF (n =27) and W-TLIF (n =30) from December 2009 to December 2010.In M-TLIF group degeneration at the L4-5 disc were noted in 11 cases and at the L5-S1 disc in 16 cases.And 19 cases were diagnosed with lumbar isthmus spondylolisthesis (17 with Grade Ⅰ spondylolisthesis and 2 with Grade Ⅱ spondylolisthesis),4 lumbar spinal stenosis and instability,2 lumbar disc herniation combined with huge posterior osteophytes,1 recurrent lumbar disc herniation after lumbar fenestration,and 1 recurrent lumbar spinal stenosis after decompression.In W-TLIF group degeneration at L4～5 disc were noted in 12 cases and at the L5-S1 disc in 18 cases.There were 19 cases diagnosed with lumbar isthmus spondylolisthesis (18 with Grade Ⅰ spondylolisthesis and 1 with Grade Ⅱ spondylolisthesis),3 with lumbar disc herniation,and 8 with lumbar spinal stenosis.Japanese Orthopedic Association (JOA) score and Visual Analogue Scale (VAS) were used to measure low back and leg pain.Modified Brantigan score was used to assess lumbar interbody fusion.Results Operative time was not significantly different between the two groups (P ＞ 0.05).Incision length and mean blood loss were (5.1 ± 0.7) cm and (90.1 ± 10.5) ml in M-TLIF group,but were (6.9 ± 1.0)cm and (155.3 ±21.2)ml in W-TLIF group (P＜0.05).At postoperative 1 and 3 days VAS in M-TLIF group was (2.1 ± 0.5) points and (1.0 ± 0.1) points respectively,but in W-TLIF group was (3.6 ± 0.1) points and (2.4 ± 1.0) points respectively (P ＜ 0.05).Intraoperative X-ray fluoroscopy frequencies were (46 ± 9) times in M-TLIF group and (7 ± 2) times in W-TLIF group (P ＜ 0.05).Mean period of follow-up was 26.7 months (range,24-36 months).At final follow-up,JOA score,VAS for leg pain and lumbar interbody fusion rate revealed no significant differences between the two groups (P ＞ 0.05),but VAS for lumbar pain was (1.0 ± 0.2) points in M-TLIF group versus (1.9 ± 0.3) points in W-TLIF group (P ＜0.05).Twenty-four cases (89％) had Brantigan score of 3 or over in M-TLIF group and 27 cases (90％) in W-TLIF group,indicating a similar interbody fusion rate (P ＞ 0.05).Conclusions Both lumbar fusion methods are effective in treatment of lumbar degenerative disease.M-TLIF lumbar fusion results in small amount of bleeding,small incision and significantly improved lower back pain as compared with W-TLIF,but W-TLIF involves less exposure to the X-rays.

Objective To review and analyze the clinical effect of combined posterior mini-invasive fixation with anterior debridement via small incision for the treatment of single segment lumbar vertebral tuberculosis. Methods Totally 31 cases with single segment lumbar tuberculosis (both borderline tuberculosis) without attachment involvement underwent one-stage anterior debridement, interbody fusion and posterior mini-invasive fixation from July 2010 to July 2015. Among these patients, 19 were male and 12 were female. The average age was (36.1±17.8) years old (ranged 21-61 years old). The average course of disease was 11(9, 12) months (ranged from 2 to 16 months). All were single segment involvement, and the involved segment was L2-3 in 7 cases, L3-4 in 10 cases, L4-5 in 6 cases, and L5-S1 in 8 cases. The clinical manifestations included lumbar back pain in 31 cases with an average pain visual analog score (VAS) of 7(6, 8) points. ASIA grade of spinal cord injury was E in 25 cases and D in 6 cases. Paravertebral abscess occurred in 22 cases and iliac fossa gravity abscess appeared in 9 cases. Kyphosis was observed in 12 cases and the average Cobb angle was 21° ± 6° . Quadruple anti-tuberculosis chemotherapy was used for at least 2 weeks preoperatively. Posterior mini-invasive fixation was fulfilled on prone position, including mini-invasive percutaneous screws in 18 cases and pedicle screw fixation via Wiltse approach in 13 cases. Posterior distraction and deformity correction were performed simultaneously for patients with kyphosis. Then the patients were changed to lateral position for anterior debridement, bone grafting and/or titanium mesh fusion. Results The average operation time was (204±54) min (ranged 160-240 min) in 31 patients, and the mean blood loss was (168±73) mL (ranged 100-300 mL). Delayed healing of anterior incision occurred in 1 case and the incision healed after two-week dressing of wound. The incision healed well in the rest 30 cases. No complications such as nerve function, blood vessel injury were found in patients. The VAS scores of the 3 days after operation were 1.3 ± 0.3 and 2.1 ± 1.4 in percutaneous group and Wiltse approach group, respectively, and the difference between them was statistically significant ( P<0.05). The VAS score of low back pain was 2(1, 3) points in all the 31 patients three months after operation, which was significantly lower than that before surgery (P<0.05). The six patients with neurological symptoms recovered to E grade after operation. The average Cobb angle correction was 15°±5° in 12 patients with kyphosis (P<0.05), which was significantly decreased compared with that before surgery (P<0.05). All patients were followed up for an average of (36.8 ± 9.3) months (ranged from 12 to 72 months). The clinical healing of tuberculosis was achieved at the final follow-up in all the 31 patients. No complications were observed, such as lumbar kyphosis, internal fixation loosening and breakage, dislocation and titanium mesh subsidence. Conclusion Mini-invasive posterior internal fixation and anterior debridement via small incision is effective for the treatment of single segment lumbar vertebral tuberculosis in lesion debridement and spine stability reconstruction by short segment fixation. This technique can reduce fused segments, surgical trauma of anterior approach and related complications.

Objective To retrospectively investigate the endoprosthetic survival and complications after custom-made tumor prosthesis replacement of knee joint.Methods From April 1996 to April 2007,85 patients with bone tumors around knee joints undergoing custom-prosthetic replacement were respectively analyzed,including 54 males and 31 females with an average of 31.33±15.3 years(range,11-72).The diagnoses were osteosarcoma(43 patients),giant cell tumor(31),chondrosarcoma(4),metastatic tumor(3),malignant fibrohistiocytoma(2),Ewing sarcoma(1),and fibrosarcoma(1).The distal femar was affected in 43 patients and the proximal tibia in 42.All patients in this group underwent wide resection and domestic custommade cemented endoprosthetic reconstruction.Results Mean following was 45.8 months.The overall complication rate was 27.1%(23/85),which was 25.6% in distal femar and 28.6% in proximal tibia.Thirteen complications occurred within 3 years after definite surgery,3 in 3-5 years,and 7 over 5 years.All of 6 operation-relation complications(wound dehiscence,periprosthetic infection,peroneal nerve injury,etc) occurred within 3 years.Seven prosthetic-related complications(prosthetic loosening or breaking,dislocation,periprosthetic fracture,etc)occurred within 3 years,3 occurred in 3-5 years,and 7 over 5 years after definite surgery.The overall endoprosthetic cumulative survival rate was 79.4%,67.7%and 62.3% after 3,5 and 7 years,respectively;which was 86.6%,79.2% and 73.5% in distal femur;66.1%,53.7% and 48.8% in proximal tibia.Conclusion All operation-related complications occurred within 3 years,prosthesis-related complications occurred mainly within 3 years and over 5 years postoperatively.Prosthesis-related complications could occur iu the early stage after using domestic custom-made prosthesis reconstruction.

Objective To describe the technique and therapeutic effect of modified unilateral laminotomy for bilateral decompression (M-ULBD) for lumbar spinal stenosis (LSS).Methods A total of 56 patients with LSS were randomly divided into group A and B.The 27 patients in group A (15 males and 12 females,with an average age of 59.4 years) underwent M-ULBD.The other 29 patients in group B (18 males and 11 females,with an average age of 61.6 years) received conventional laminectomy.JOA score of low back pain,VAS,CPK three days after operation,pre-and post-operative cross-sectional areas of multifidus were used to evaluate the clinical results.Results A total of 45 patients (21 in group A and 24 in group B) completed 2 years of follow-up.The preoperative VAS of low back pain,leg pain,numbness,JOA score and cross-sectional areas of multifidus were 5.6±1.7,7.1±0.4,11.6±2.6,5.8±1.8 cm2 in group A and 6.2±1.2,7.9±1.3,10.9±1.0,6.1±2.0 cm2 in group B.There was no significant difference in preoperative data between both groups.The union of split spinous process was observed in all cases 6months later according to computed tomography.The postoperative CPK was lower in group A.The postoperative JOA and VAS scores in both groups were improved significantly compared with the corresponding preoperative ones.The VAS of leg pain,numbness,JOA score,and JOA recover rate in latest follow-up were 1.3±0.2,1.5±0.7,26.7±2.1,86.1％±3.1％ in group A,and 1.7±0.3,2.0±1.3,24.3±2.5,83.6％±6.4％ in group B,respectively.All these data have no difference between group A and B.The VAS of low back pain and atrophy rate of multifidus were 1.0±0.5,6.4％±1.2％ in group A,and 2.6±0.7,15.7％±3.0％ in group B respectively.All these data are lower in group A.Conclusion Our two years follow-up shows that this method is efficient for lumbar spinal stenosis treatment,however,it still need long term follow-up and to compare with other modified methods.

Objective To evaluate the changes in the expression of transient receptor potential vanilloid 1 (TRPV1) in dorsal root ganglions (DRGs) during remifentanil-induced hyperalgesia in the rats with incisional pain.Methods Thirty-two SPF healthy male Sprague-Dawley rats,weighing 240-260 g,aged 2-3 months,in which caudal catheters were successfully implanted,were divided into 4 groups (n=8 each) using a random number table:control group (group C),incisional pain group (group Ⅰ),remifentanil group (group R),and incisional pain + remifentanil group (group I+R).A 1 cm longitudinal incision was made through skin,fascia and muscle of the plantar aspect of the left hindpaw to establish the model of incisional pain.In group R,remifentanil was intravenously infused for 60 min at a rate of 1.2 μg · kg-1 · min-1.In group Ⅰ,the model of incisional pain was established,and the equal volume of normal saline was intravenously infused for 60 min at the same time.In group I+R,the model of incisional pain was established,and remifentanil was intravenously infused for 60 min at a rate of 1.2 μg · kg-1 · min-1 at the same time.In group C,the equal volume of normal saline was intravenously infused for 60 min.The mechanical paw withdrawal threshold (MWT) and thermal paw withdrawl latency (TWL) were measured at 24 h before normal saline or remifentanil infusion (To) and 2,6,24 and 48 h after the end of infusion (T1-4).The rats were sacrificed after the last measurement of pain threshold,and the DRGs of the lumbar segment (L4-6) were removed for determination of the expression of TRPV1 protein and mRNA by Western blot and real-time polymerase chain reaction,respectively.Results Compared with group C,the MWT was significantly decreased,and the TWL was shortened at T1-4,and the expression of TRPV1 protein and mRNA was up-regulated in R,I and I+R groups (P＜0.05).Compared with group R or group I,the MWT was significantly decreased,and the TWL was shortened at T1-4,and the expression of TRPV1 protein and mRNA was up-regulated in group I+R (P＜0.05) Conclusion Up-regulated expression of TRPV1 in DRGs may be involved in the mechanism underlying remifentanil-induced hyperalgesia in the rats with incisional pain.

Objective:To investigate and compare the biomechanical strength of paravertebral foramen screws (PVFS), lateral mass screws (LMS) and pedicle screws (PS).Methods:A total of 30 human cervical spine vertebrae (C 3-C 6) were harvested from 8 fresh-frozen cadaver specimens whose mean age was 45.3±11.2 years at death. The vertebrae were randomly divided into three groups for specific screws. For each vertebra, one side was randomly chosen for direct pullout strength test (speed 5 mm/s), and the other side for fatigue test (displacement ±1.0 mm, frequency 1 Hz, 500 cycles) and residual pullout strength test. 4.5 mm × 12 mm screws were used for PVFS, 3.5 mm × 14 mm screws for LMS, and 3.5 mm × 24 mm screws for PS. Results:The direct pullout strength was 327.10±17.07 N for PVFS, 305.71 ± 11.63 N for LMS, and 635.67 ± 22.82 N for PS. The residual pullout strength was 265.62 ±18.19 N for PVFS, 192.80 ±17.10 N for LMS, and 494.89 ±41.79 N for PS. The residual pullout strength of PVFS, LMS and PS respectively, compared with the direct pullout strength, decreased by 18.8%, 36.93% and 22.15% ( tPVFS=7.795 , tLMS=17.267 , tPS=9.349 , P<0.001). The direct pullout strength of PS was higher than that of PVFS and LMS( t=34.245, t=40.741, P< 0.001), as well as PVFS was slightly higher than LMS ( t=3.275, P=0.004). The residual pullout strength of PS was the highest, PVFS was the second, and LMS was the smallest ( F=314.619, P<0.001). For the fatigue test, the load at the first cycle and the first time when the set position was reached of PVFS were higher than those of LMS ( t=3.625, P=0.002; t=5.388, P<0.001) and PS ( t=2.575, P=0.019; t=2.680, P=0.015), but there was no difference between those of LMS and PS ( t=0.609 , P=0.550; t=1.953 , P=0.067). The load at the last cycle of PVFS and PS was higher than that of LMS ( t=5.341 , P<0.001 ; t=3.439 , P=0.003), while there was no difference between PVFS and PS ( t=1.606, P=0.126). Conclusion:The direct pullout strength of PVFS was slightly higher than that of LMS, and the residual pullout strength was significantly higher than LMS. The property of fatigue resistance of PVFS was similar to PS and obviously better than LMS. In summary, PVFS can be used as an effective substitute for LMS and PS.