Effects and mechanisms of melatonin on autophagy and inhibition of hepatic stellate cell proliferation / 安徽医科大学学报

Objective @# To investigate the effects of melatonin ( MEL) on the proliferation of hepatic stellate cells (HSCs) induced by platelet - derived growth factor (PDGF⁃BB) and explore its correlation with the regulation of autophagy levels . @*Methods @#The HSC⁃T6 cells were divided into the following groups : control group , model group and MEL (low , medium and high) treatment groups . After 24 hours culture , the cells adhered to the wall and were changed into serum⁃free DMEM medium to synchronize the cells to the G0 stage . After 24 hours culture , all groups were given with PDGF ⁃ BB ( 10 ng/ml) excepted the control group . Besides , melatonin of different concentrations ( 1 nmol/L , 1 μmol/L and 0. 1 mmol/L) were added immediately in three treated groups . After incubated for 48 hours , the effect of MEL on the proliferation of hepatic stellate cells activated by PDGF⁃BB was detected by CCK8 method . The protein expression levels of LC3b and α ⁃SMA in hepatic stellate cells were determined by Western blot . The expression levels of LC3b mRNA and α ⁃SMA mRNA in hepatic stellate cells were determined by qRT⁃PCR . The ultrastructure of HSCs was observed by transmission electron microscopy to understand the autophagy level.@*Results @# Compared with control group , PDGF⁃BB could induce the proliferation of HSCs ( P < 0. 01) . Compared with model group , MEL inhibited the proliferation of HSCs activated by PDGF⁃BB ( P < 0. 01) . Compared with the control group , LC3b and α ⁃SMA protein expressions significantly increased in the model group ( all P < 0. 05) , and LC3b mRNA and α ⁃SMA mRNA expressions significantly increased in the model group (P < 0. 05 , P < 0. 01) . Compared with the model group , MEL could inhibit such effects (LC3b : P < 0. 05 , P < 0. 01 ; α ⁃SMA : P < 0. 01) . Transmission electron microscopy ( TEM) showed that compared with the control group , autopolysosome significantly increased in the model group (P < 0. 05) . Compared with model group , autopolysosome significantly decreased in MEL treatment group (P < 0. 01) . @*Conclusion @#The up⁃regulation of autophagy level can promote the proliferation of hepatic stellate cells and the inhibition of hepatic stellate cell proliferation by MEL may be related to the down⁃regulation of autophagy level .

Wiltse approach combined with contralateral transforaminal lumbar interbody fusion and conventional surgery for lumbar disc herniation:a case-control study / 中国骨伤

OBJECTIVE@#To compare the clinical effecty of Wiltse approach combined with contralateral transforaminal lumbar interbody fusion (TLIF) and traditional TLIF in the treatment of lumbar disc herniation and its affect on injury of multifidus muscle.@*METHODS@#From June 2014 to September 2017, 90 patients with lumbar disc herniation combined with lumbar spine instability were divided into two groups (Wiltse approach group and traditional group) depend on the procedure of operation. Wiltse approach group was treated with Wiltse approach screw placement in one side combined with contralateral TLIF. There were 50 patients in Wiltse approach group, including 36 males and 14 females, aged 45 to 72 yearswith an average of (60.4± 3.1) years. The traditional group was treated with traditional TLIF operation. There were 40 patients in the traditional group, including 25 males and 15 females, aged 45 to 74 years with an average of (62.1±3.4) years. The operative time, intraoperative blood loss, accuracy of screw implantation, postoperative drainage volume and drainage tube removal time were recorded in two groups. Visual analogue scale (VAS) and Oswestry Disability Index (ODI)were observed before and 12 months after operation. All patients underwent CT examination preoperative and 12 months postoperative, and the CT values of bilateral multifidus muscle were measured.@*RESULTS@#All the patients were followed up, 40 patients in traditional group were 12 to 18 months with an average of (15.3±4.3) months; and 50 patients in Wiltse approach group were 13 to 24 months with an average of (16.5± 4.1) months. There were no statistically significant differences in operative time and intraoperative blood loss between two groups (@*CONCLUSION@#Compared with traditional surgical procedures, the Wiltse approach nail placement combined with contralateral TLIF has the advantage of accurate nail placement, reducing multifidus muscle damage, and reducing the incidence of postoperative intractable low back pain.

Etiological analysis of surveillance cases of diarrhea syndrome in Gansu Province from 2009 to 2018 / 中华疾病控制杂志

@#Objective To understand pathogenic distribution and epidemiological characteristics of diarrhea syndrome in Gansu Province． Methods Fecal specimens from diarrhea syndrome surveillance cases at sentinel hospitals in Gansu Province from 2009 to 2018 were collected，and virus nucleic acids were detected by real－time fluorescent chain reaction，and bacteria were detected by isolation culture． Ｒesults 1 547 positive cases were detected from 4 406 stool specimens with the positive rate of 35. 11%． Among the positive samples，1 281 cases were positive for virus with the positive rate of 47. 20%; 287 ca- ses were positive for bacteria with the positive rate of 8. 57%． Top five of pathogenic spectrum were rota- virus ( 46. 04%) ，astrovirus ( 13. 37%) ，norovirus ( 13. 15%) ，Shigella ( 9. 90%) and adenovirus ( 7. 81%) ． In different age groups，statistically significant differences were found in the positive rates of rotavirus，norovirus，astrovirus，Shigella and non typhoid Salmonella ( all P＜0. 05) ． The positive rate of virus was higher from November to March of next year，and the positive rate of bacteria was higher from June to August． The epidemic seasons of pathogens were different，of which rotavirus was dominating in four seasons． Conclusions The pathogenic spectrum of diarrhea is wide relatively in Gansu Province， and viral diarrhea is more common，with obvious seasonal peak． Continuous monitoring should be strengthened to grasp characteristics and epidemic trends of pathogens，and it is helpful to take targeted and seasonal preventive measures in population at high risk．

Influence factors and predictive ability of a risk prediction model for carotid atherosclerosis in a follow-up population / 中华疾病控制杂志

Objective To explore factors influencing the incidence of carotid atherosclerosis in different genders so as to provide reference for the specific prevention of the disease. Methods A nested case-control study was conducted to analyze factors influencing the incidence of carotid atherosclerosis in Jinchang cohort population who were randomly selected through stratified sampling by age and followed up. A risk prediction model was established and the goodness of fit was evaluated by the area under the receiver operator characteristic curve (ROC). Results The standardized incidence of carotid atherosclerosis in this follow-up population was 12.32%, and the incidence rate of males (13.65%) was greater than that of females (11.29%). The difference was statistically significant ( 2=4.267, P<0.001). Age, education, elevated systolic blood pressure, and elevated low-density lipoprotein cholesterol were common risk factors for carotid atherosclerosis in both men and women. Elevated fasting plasma glucose (OR=2.556, 95% CI: 1.618-4.038) and elevated triglyceride (OR=1.535, 95% CI: 1.058-2.227) were only associated with men. Abdominal obesity (OR=1.414, 95% CI: 1.013-1.974) was only associated with women. The area under ROC of male and female prediction models was 0.835 (95% CI: 0.815-0.856) and 0.809 (95% CI: 0.788-0.831), respectively. The sensitivity was 78.0% and 78.9%, the specificity was 78.8% and 73.1%, and the diagnostic coincidence rate was 91.3% and 82.4%, respectively. Conclusions There are different risk factors for carotid atherosclerosis in males and females, and targeted prevention and control measures should be taken according to gender. The risk prediction model established by Logistic regression had certain guiding value.

Zika virus NS3 can unwind dsDNA depending on ATP hydrolysis / 基础医学与临床

Objective To investigate whether Zika virus NS3 has ATP hydrolase and DNA helicase activity. Methods Zika NS3 with His tag was expressed in E.coli BL21 and purified by Nicke lagarose beads.ATP hy-drolysis assay was performed to examinethe ATPase activity of NS3.The dsDNA unwinding activity of NS3 was detected according to the principle of fluorescence resonance energy transfer(FRET).NS3 G198A mutant was generated by site-directed mutagenesis and its enzymatic activity was measured subsequently.Results Zika NS3 was capable of hydrolyzing ATP in vitro[Vmax=2.76 μmol/(L· min),Km=0.11 mmol/L].Moreover, Zika NS3 could unwind dsDNA in vitro as that proved by the fluorescence was enhancement in FRET system.G198A mutation impaired NS3 enzymatic activities, including ATP hydrolysis and dsDNA unwinding activities.Conclu-sions Zika NS3 has DNA helicase activity in vitro depending on ATP hydrolysis,and the glycine 198 is impor-tant for its enzymatic activity.

Case control study of unilateral and bilateral intervertebral space release in the treatment of lower lumbar spondylolisthesis / 中国骨伤

OBJECTIVE@#To analyze the clinical efficacy of unilateral and bilateral intervertebral space release in the treatment of lower lumbar spondylolisthesis.@*METHODS@#The clinical data of 41 patients with lumbar spondylolisthesis treated by surgery from October 2012 and May 2016 were retrospcetive analyzed. The patients were divided into two groups, 18 cases were enrolled in unilateral intervertebral release group, there were 7 males and 11 females, aged from 47 to 75 years old with an average of (59.3±6.4) years; according to Meyerding classification, 9 cases of I degree, 7 cases of II degree, 2 cases of III degree. And 23 cases were bilateral release group, there were 11 males and 12 females, aged from 51 to 76 years old with an average of (58.2±5.7) years; according to Meyerding classification, 11 cases of I degree, 10 cases of II degree, 2 cases of III degree. The operation time, intraoperative blood loss, bone graft fusion rate of the patients were recorded in the patients. Pre- and post-operative back and leg pain were evaluated by visual analogue scale (VAS) between two groups. The slip rate, slip angle, posterior height of intervertebral space, height of intervertebral foramen, distance of anterior and posterior displacement of vertex of intervertebral foramen were measured on X-ray and CT. And the above radiographic data were analyzed by intra-group or inter-group.@*RESULTS@#All the patients were followed up from 9 to 24 months with an average of 12 months. The entire 41 patient obtained bone fusion at 12 months after operation. There was no statistical significance in VAS at 12 months after operation, intraoperative blood loss and operation time between two groups(>0.05). There were statistical significance in sliding angle, posterior height of intervertebral space, height of intervertebral foramen, distance of anterior and posterior displacement of vertex of intervertebral foramen of all patients before and after operation(0.05), but there was significant difference in bilateral release group. There was statistical significance in postoperative slip angle, posterior height of intervertebral space, distance of anterior and posterior displacement of vertex of intervertebral foramen between two groups(=0.001, 0.045, 0.001). The height of intervertebral foramen increased and the slippage rate decreased in both groups after operation, but there was no significant difference between two groups(=0.248).@*CONCLUSIONS@#Unilateral and bilateral intervertebral space release for the treatment of lumbar spondylolisthesis can obviously reduce the rate of spondylolisthesis, restore foraminal height and achieve better clinical efficacy. Bilateral release group can better restore the slip angle, increase posterior height of intervertebral space, reduce the distance of anterior and posterior displacement of vertex of intervertebral foramen. Especially for grade II or above degree of slippage is more appropriate.

Metrical analysis of disc-condyle relation with different splint treatment positions in patients with TMJ disc displacement

Abstract Objective: To evaluate the effect of bite positions characterizing different splint treatments (anterior repositioning and stabilization splints) on the disc-condyle relation in patients with TMJ disc displacement with reduction (DDwR), using magnetic resonance imaging (MRI). Material and Methods: 37 patients, with a mean age of 18.8±4.3 years (7 male and 30 females) and diagnosed with DDwR based on the RDC/TMD, were recruited. MRI metrical analysis of the spatial changes of the disc/condyle, as well as their relationships, was done in three positions: maximum intercuspation (Position 1), anterior repositioning splint position (Position 2), and stabilization splint position (Position 3). Disc/condyle coordinate measurements and disc condyle angles were determined and compared. Results: In Position 1, the average disc-condyle angle was 53.4° in the 60 joints with DDwR, while it was −13.3° with Position 2 and 30.1° with Position 3. The frequency of successful "disc recapture" with Position 2 was significantly higher (58/60, 96.7%) than Position 3 (20/60, 33.3%). In Positions 2 and 3, the condyle moved forward and downward while the disc moved backward. The movements were, however, more remarkable with Position 2. Conclusions: Anterior repositioning of the mandible improves the spatial relationship between the disc and condyle in patients with DDwR. In addition to anterior and inferior movement of the condyle, transitory posterior movement of the disc also occurred.

Effect of reduction on spino-pelvic parameters in treating high-grade lumbar spondylolisthesis / 中国骨伤

<p><b>OBJECTIVE</b>To explore the effect of reduction on spino-pelvic balance in treating high-grade lumbar spondylolisthesis.</p><p><b>METHODS</b>From Augest 2008 to Augest 2011, the data of 16 patients with high-grade lumbar spodylolisthesis (Meyerding grade III or more than grade III) underwent reduction treatment through posterior approach were retrospectively analyzed. There were 9 males and 7 females, aged from 24 to 65 years old with an average of 44 years. Preoperative, postoperative at 2 weeks and final follow-up, spino-pelvic parameters of all patients were measured and compared by total legth lateral X-rays, and spino-pelvic parameters included sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), lumbar lordosis (LL) and sagittal vertical axis (SVA); the informations of intervertebral bone fusion was observed by CT and postoperative complications were recorded; clinical effects were assessed according to clinical Oswestry score (CODI).</p><p><b>RESULTS</b>All patients were followed up from 12 to 24 months with an average of 18 months. Four cases reduced anatomically, 8 cases reduced to grade I .4 cases reduced to grade II. There was statistically significant differences in sacral slope (SS), pelvic tilt (PT), lumbar lordosis angle (LL) and sagittal vertical axis (SVA) between before operation and two weeks after operation (P < 0.05), while pelvic incidence (PI) no statistically significant differences was found between before operation and two weeks after operation (P > 0.05). There was no statistically significant differences in SS, PT, LL, SVA, PI between two weeks after operation and final follow-up (P > 0.05). CODI had decreased from preoperative 36.6 ± 4.2 to 14.7 ± 4.0 at final follow-up (P < 0.05). One year after operation, all patients obtained bone fusion and can find the union of bone trabeculae by three-dimensional reconstruction CT. Three cases occurred transient nerve root pain, and recovered after medicinal treatment. No infection and internal fixation loosening and breakage were found.</p><p><b>CONCLUSION</b>Surgical reduction for high-grade lumbar spondylolisthesis can improve spino-pelvic balance and acquire satisfactory outcomes.</p>

Posterior reduction and interbody fusion for the treatment of thoracolumbar fractures and dislocations / 中国骨伤

<p><b>OBJECTIVE</b>To explore efficacy of posterior reduction and interbody fusion in treating thoracolumbar fractures and dislocations.</p><p><b>METHODS</b>From August 2004 to May 2009, 24 patients (18 males and 6 females with an average of 38.2 years, ranged 24 to 56 years old) were treated. Among them, 14 cases were by traffic accident,6 cases were falling down, 2 cases were heavy hit, 2 cases were transverse crush. According to AO classification, 12 cases were type B1, 5 cases B2, 2 cases B3,3 cases C1, 2 cases C2. One cases in T(10,11), 2 cases in T(11,12), 5 cases in T12L1, 8 cases in L(1,2), 2 cases in L(2,3), 4 cases in L(3,4), 2 cases in L4/5. Acoording to Frankle classification,5 cases in grade A, 9 cases in grade B, 8 cases in grade C and 2 cases in grade D. The reduction, graft healing and recovery of nervous function were followed up.</p><p><b>RESULTS</b>All patients were followed up from 8 to 33 months with an average of 16 months. The operation time was for 3.0 to 5.8 hours, meaned 3.7 h, and mean blood loss was 860 ml (ranged, 500 to 1800 ml). Cobb angle improved from preoperative (32.6 +/- 3.7) degrees to postoperative (13.7 +/- 2.4) degrees. The anterior high of fractured vertebrae increased from preoperative (41.0 +/- 11.6)% to postoperative (87.6 +/- 2.3)% .Three cases of 5 cases with Frankle A were not recovery, 1 case changed to grade B, 1 case changed to grade C; Five cases of 9 cases with Frankle B were changed to grade C, 3 cases to grade D, 1 case changed to grade E; Five cases of 8 cases with Frankle C were changed to Grade D, 3 cases to Grade E; Two cases with Frankle D were recoved to normal. Planting bone surface got bone fusion, and no internal fixation lossen, dislocation occurred.</p><p><b>CONCLUSION</b>Posterior reduction and rigid interbody fusion for the treatment of thoracolumbar fractures and dislocations can receive satisfactory fusion based on recovering normal spinal sequence</p>

Anatomic comparison between spinous process screws and pedicle screws techniques of the second cervical vertebar / 中国骨伤

<p><b>OBJECTIVE</b>To compare anatomic difference between spinous process screws and pedicle screws techniques of the second cervical vertebra.</p><p><b>METHODS</b>Ten human cadaveric of cervical spine (5 male, 5 female) were harvested and had no gross deformities such as scoliosis and/or kyphosis were found in the study. The average age of the subjects was 60.5 years. The specimens were placed in the prone position. Posterior cervical exposure was attained by dissecting all soft tissue off the posterior aspect of the second cervical vertebra. After clear exposure of the lateral mass,the spinous process screw and pedicle screw insertion techniques were performed in this study. Each technique involved ten specimens and 10 screws inserted into C2 bilaterally. The one side of C2 was randomly selected for the spinous process screw and the other side was designate for the pedicle screw. This point then was drilled with a 3 mm drill, and followed by placement of a 4.0 mm cortical screw. The starting point for spinous process screw insertion was located at the junction of the lamina and the spinous process and the direction of the screw was about 0 degrees caudally in the sagittal plane and about O0 medially in the axial plane. The starting point of pedicle screw should be the midpoint of the base of inferior articular facet of the axis. The drilling angle was 15 degrees to 20 degrees in the superior direction and 30 degrees in the medial direction. After screw placement, all the specimens were CT scaned. On the CT scan,the length of the spinous process screw and pedicle screw trajectory were measured. Results were recorded for each screw that violated impinged of the pedicle, spinal canal and transverse process foramen.</p><p><b>RESULTS</b>All the C2 spinous process screws were successfully placed, without impingement the spinal cord, the vertebral artery and the breakage of the spinous process. There was one pedicle screw breaking the pedicle into the vertebral artery foramen. The trajectory length for the spinous process screws were (21.4 +/- 1.4) mm,compared with the pedicle screws (23.7 +/- 1.0) mm. But there was no significant differences between spinous process screws and pedicle screws techniques (t = -4.387, P > 0.05).</p><p><b>CONCLUSION</b>The C2 spinous process screw fixation has the anatomic feasibility and is easier to perform than pedicle screw fixation.</p>

Clinical study of posterior transarticular fixation with rod-screw in the lower cervical vertebrae / 中国骨伤

<p><b>OBJECTIVE</b>To explore the effects of posterior transarticular fixation with rod-screw in treating fracture and dislocation, spinal stenosis of lower cervical vertebrae.</p><p><b>METHODS</b>From July 2005 to July 2009,11 patients with cervical fracture and dislocation and 9 with spinal stenosis of lower cervical vertebrae underwent operation with transarticular fixation with rod-screw (Vertex system). There were 16 cases male and 4 cases female, ranging in age from 29 to 76 years with an average of 51 years. All patients underwent decompression,internal fixation and fusion through posterior approach (combined with anterior approach in 3 cases). The method of insertion of screw: the starting point located in medial 1 mm of the midpoint of the lateral mass, angle in sagittal plane was 15 degrees-20 degrees of caudal clinism and in coronal plane was 35 degrees-40 degrees of external clinism. The position of screws, the cervical array, bone graft and fusion were observed by X-ray films.</p><p><b>RESULTS</b>A total of 88 transarticular screws were successfully inserted, 10 screws located in C3,4, 20 in C4,5, 32 in C5,6, 26 in C6,7. There were no complications related to screw insertion, such as injury of the vertebral artery, nerve roots and the spine cord. All patients obtained bone fusion without internal fixation breaking. The improvement rate of JOA was 55.8% at the 1st week after operation, 5 cases got excellent results, 7 good, 7 fair, 1 poor; the improvement rate of JOA was 74.5%, at the 3rd month after operation, 6 cases got excellent results, 8 good, 6 fair. There was significant difference in the JOA between before operation and at the 3rd month after operation.</p><p><b>CONCLUSION</b>The transarticular screw fixation with rod-screw in the lower cervical spine is an effective fixation, which has advantages of rigid stability, convenience to perform, and can reduce operative risk in initial application, but the long-term follow-up is very necessary.</p>

An anatomic study of posterior C(2) spinous process laminar screw fixation / 中华外科杂志

<p><b>OBJECTIVES</b>To explore the feasibility and the technical parameters in posterior C2 spinous process laminar screw fixation, and discuss the clinic significance of C2 spinous process laminar screws.</p><p><b>METHODS</b>Twenty cervical cadaveric spines of C2 were dissected, with care taken to expose the lamina and spinous process. After the entrance point of spinous process screw were determined, posterior C2 spinous process laminar screw implantation was performed under visual control. On the morphologic CT scan, the angle and length of the spinous process laminar screw trajectory and the distance between the tip of the screw and the spinal cord and the vertebral artery were measured.</p><p><b>RESULTS</b>The C2 spinous process laminar screws were successfully placed, without impingement of the spinal cord and the vertebral artery. There were little differences between superior and inferior screws in the angle, trajectory length and the distance between the tip of the screw and the spinal cord and the vertebral artery, but without significance (P > 0.05). The placed angles of the screws were 76.8° ± 10.6° in the axial plane. The distance between the tip of the screw and the spinal cord and the vertebral artery was (5.3 ± 1.6) mm and (17.4 ± 3.7) mm respectively. The trajectory length was (23.1 ± 3.2) mm.</p><p><b>CONCLUSIONS</b>Posterior C2 spinous process laminar screw fixation is feasible. C2 spinous process laminar screw fixation affords an alternative to standard screw placement for plate fixation and cervical stabilization.</p>

Clinical observation of mid-stage complications after cervical disc replacement / 中国骨伤

<p><b>OBJECTIVE</b>To summarize the therapeutic experience of Bryan prosthetic cervical disc replacement at the 3rd years after operation and to analyze the clinical effect, incidence rate of heterotopic ossification, conditions of prosthetic fusion in order to investigate the countermeasures.</p><p><b>METHODS</b>From December 2005 to December 2008, 54 patients with cervical syndrome (34 males and 20 females, the age was from 39 to 69 years with an average of 50.5) were treated with single level Bryan prosthetic cervical disc replacement. The patients were followed for 24-36 months with an average of 30 months. The symptoms and nerve function were evaluated according to JOA and Odom's scoring. The anterior-posterior and lateral cervical X-ray films were also taken regularly every three months for the observation of heterotopic ossification and prosthetic fusion. Meanwhile, the X-ray films of the forward bending, extending, left and right lateriflection were taken before operation and at the 1st years after operation for the measurement of the stability and rang (ROM) of replaced levels.</p><p><b>RESULTS</b>The pain symptom and neurological function of all 54 patients were improved obviously. JOA score increased with an average of 76.1%, and ROM of replaced levels also improved obviously. The incidence rate of heterotopic ossification and prosthetic fusion went up year by year, 3.7% (2/54) for the first year, 16.7% (9/54) for the second year and 22.2% (12/54) for the nearly third year.</p><p><b>CONCLUSION</b>Bryan prosthetic cervical disc replacement has better mid-stage results than conventional methods. Modified surgical methods and early rehabilitation exercise may reduce the relatively high incidence rate of heterotopic ossification and prosthetic fusion.</p>

Anatomical considerations for the placement of C₂ spinous process screws / 中华外科杂志

<p><b>OBJECTIVES</b>To quantitatively anatomically evaluate the C₂ spinous process, analyze the anatomical feasibility of the C₂ spinous process screws and its clinical significance.</p><p><b>METHODS</b>To dissect and evaluate 30 cervical cadaveric spines of C₂ which were taken to expose the lamina and spinous process. Anatomic quantitative evaluation of the C₂ spinous process included its height and width. Twenty cervical cadaveric spines of C₂ were chosen to the study of the placement of the C₂ spinous process screws. The starting point for the C₂ spinous process screw insertion was located at the base of the spinous process. After the entrance point of spinous process screws was determined, posterior C₂ spinous process screw implantation was performed bilaterally under direct visualization. On the morphologic CT scan, the width of C₂ spinous process base, the angle and length of the spinous process screw trajectory, and the distance between the tip of the screw and the spinal cord and the vertebral artery were measured.</p><p><b>RESULTS</b>The average height and width of the C₂ spinous process were (12.90 ± 1.30) mm and (18.86 ± 1.17) mm respectively. The C₂ spinous process screws were successfully placed without impingement the spinal cord or the vertebral artery and the breakage of the spinous process. On the CT scan, the average width of the base of C₂ spinous process was (20.7 ± 1.3) mm. The placed angles of the screws were 1.8° ± 1.0° in the axial plane. The distance between the tip of the screw and the spinal cord or the vertebral artery was (8.3 ± 2.6) mm and (20.2 ± 3.1) mm respectively. There were little differences between superior and inferior screws in the angle, the distance between the tip of the screw and the spinal cord or the vertebral artery, but without significance (P > 0.05). The average trajectory length of the C₂ spinous process screws was (19.7 ± 1.1) mm. The average trajectory length of the superior spinous process screws was shorter than that of inferior spinous process screws, with great differences (t = 3.566, P < 0.01).</p><p><b>CONCLUSIONS</b>There is the anatomic feasibility of the C₂ spinous process screw fixation which may afford an alternative to standard screw placement for axis fixation. The biomechanical study for the C₂ spinous process screw is also necessary.</p>

Quantitative anatomic study on atlas and designation of bionic plating of anterior arch of atlas / 中国骨伤

<p><b>OBJECTIVE</b>To observe and measure specimen of Chinese atlas to obtain morphological parameter, providing anatomic data for designing bionic plating of anterior arch of atlas.</p><p><b>METHODS</b>The anatomic parameters of 48 sets of fresh Chinese adults' atlas specimens were measured with a electric digital caliper and a goniometer, including width of anterior arch of atlas (AW), thickness of atlas at the junction of anterior arch and lateral mass (AD), thickness and height of anterior tubercle of atlas (AT and AH), middle height, length and width of the lateral mass (MHL, L and LW), the extraversion angle of lateral mass of atlas (alpha degrees) and so on. The data were statistically analyzed in order to ascertain the range of morphological parameter of bionic plating of anterior arch of atlas.</p><p><b>RESULTS</b>The measurement results showed that AW was (20.68 +/- 1.38) mm, AD was (3.86 +/- 1.42) mm, AT was (8.65 +/- 1.88) mm, AH was (10.36 +/- 1.49) mm, MHL was (12.82 +/- 1.76) mm, LW was (12.86 +/- 1.63) mm, the extraversion angle of lateral mass of atlas (alpha degrees) was (13.84 +/- 1.73) degrees. The plating was composed of connecting plate of anterior arch of atlas and fixing plate of atlas lateral mass in bilateral.</p><p><b>CONCLUSION</b>The designation of bionic plating of anterior arch of atlas is feasible on morphology. The bionic plating of anterior arch of atlas can not only rebuild the stability of atlas, but also reserve the rotation function between atlas and axis. The plating could be used for patient suffering from instability of upper cervical because of atlas affection.</p>