An ultrasound-guided robot assisted system for percutaneous facet joint puncture: an experimental study / 中华创伤骨科杂志

Objective:To evaluate the accuracy of an ultrasound-guided robot-assisted system for percutaneous facet joint puncture in an animal experiment by registration of ultrasound images and two-dimensional X-ray fluorescence images.Methods:Six specimens of fresh adult sheep lumbar spine were prepared and soaked in gelatin solution. The specimens contained a total of 48 facet joints with 24 ones respectively on the left and right sides. Half of the joints were assigned by the random number table method into a robot-assisted group which were subjected to percutaneous facet joint puncture assisted by the ultrasound-guided robot-assisted system while the contralateral ones into a freehand group which were subjected to percutaneous facet joint puncture by freehand. In the robot-assisted group, the left facet joints were 3 L 1, 3 L 2, 3 L 3 and 3 L 4 ones while the right facet joints were 2 L 1, 3 L 2, 5 L 3 and 2 L 4 ones. In this self-control animal experiment, both the robot-assisted punctures and the freehand punctures were carried out in the same specimen. The puncture success rate, puncture needle adjustment, positioning deviation, orientation deviation and operation time were recorded. Results:The positioning deviation and orientation deviation in the robot-assisted group [(2.21 ± 1.12) mm and 1.51° ± 0.47°] were significantly lower than those in the freehand group [(3.26 ± 1.44) mm and 2.24° ± 0.89°] ( P < 0.05). All the articular facet joint punctures were successfully accomplished for the first time in the robot-assisted group while those required multiple adjustments in the freehand group. In the robot-assisted group, the total operation time [(463.84 ± 34.93) s] was significantly longer than that in the freehand group [(298.40 ± 27.48) s], but the puncture time [(37.97 ± 6.87) s] was significantly shorter than that in the freehand group [(261.61 ± 33.15) s] ( P < 0.05). Conclusion:The ultrasound-guided robot-assisted system for percutaneous facet joint puncture can lead to accurate puncture with limited needle adjustments.

Association between skin advanced glycation end products and carotid atherosclerosis in population with normal glucose regulation / 中华健康管理学杂志

Objective:To investigate the association between skin advanced glycation end products (AGEs) and carotid atherosclerosis (AS) in subjects with normal glucose regulation (NGR).Methods:This was a cross-sectional study. Data from the Health Management Center of the First Affiliated Hospital of University of Science and Technology between January 2019 to June 2019 were collected. A total of 902 NGR subjects aged 40-79 were enrolled and categorized into control group (530 cases), carotid intima-media thickness (IMT) thickening group (150 cases), and carotid atherosclerosis plaque group (222 cases) based on the carotid ultrasound results. Data as follows were collected, gender, age, blood pressure, body mass index (BMI), triglyceride (TG), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), fasting blood glucose (FPG), glycosylated hemoglobin (HbA 1c) and skin AGEs. Comparison via ANOVA analysis were carried out among the 3 groups. Logistic regression analysis was used to screen the independent influencing factors of carotid atherosclerosis plaque. Spearman correlation analysis was used to evaluate the correlation between AGEs and other parameters, and receiver operating characteristic (ROC) curve was used to evaluate the efficiency of skin AGEs in predicting carotid atherosclerosis plaque in NGR subjects. Results:Among the control group, IMT thickening group and carotid atherosclerosis plaque group, gender, age, systolic blood pressure (SBP), diastolic blood pressure (DBP), TC, LDL-C, FPG, HbA 1c, AGEs were significantly different (all P<0.05). Compared with IMT thickening group, the age, SBP and AGEs of carotid atherosclerotic plaque group were higher [55 (50, 60) vs 53 (49, 56) year; 132 (122, 141) vs 126 (115, 142) mmHg(1 mmHg=0.133 kPa); 74 (67, 81) vs 72 (67, 78) AU] (all P<0.001); compared with the control group, age, LDL-C, HbA 1c and AGEs of IMT thickening group were higher [53 (49, 56) vs 48 (45, 52) year; (2.8±0.7) vs (2.7±0.7) mmol/L; 5.4% (5.2, 5.6)% vs 5.4% (5.1, 5.6)%; 72 (67, 78) vs 70 (66, 76)] (all P<0.05). Age ( OR=1.179, 95% CI: 1.107-1.255), SBP ( OR=1.045, 95% CI: 1.013-1.077), LDL-C ( OR=2.028, 95% CI: 1.036-3.969), AGEs ( OR=1.049, 95% CI: 1.000-1.100) were independent influencing factors of carotid atherosclerotic plaque in population with normal glucose regulated (all P<0.05). AGEs was positively correlated with age, HbA 1c and carotid atherosclerosis plaque ( r=0.407, 0.092, 0.172) (all P<0.01). The area under the ROC curve of skin AGEs for identifying carotid atherosclerotic plaque in NGR population was 0.650 (95% CI 0.601-0.698), the best cutoff value was 70.5, the sensitivity was 65.8%, and the specificity was 56.9%. Conclusion:Skin AGEs level is closely associated with the occurrence of carotid atherosclerosis in NGR subjects.

Robot-assisted percutaneous minimally invasive pedicle screwing for multi-segmental thoracolumbar fractures / 中华创伤骨科杂志

Objective:To investigate the clinical effects of robot-assisted minimally invasive percutaneous pedicle screwing in the treatment of multi-segmental thoracolumbar burst fractures without neurological dysfunction.Methods:A retrospective analysis was conducted of the 24 patients who had been treated at Department of Orthopaedics, Hospital Affiliated to Inner Mongolia Medical University for multi-segmental thoracolumbar fractures from January 2019 to December 2020. They were randomly divided into a robot group ( n=12) in which the minimally invasive percutaneous pedicle screwing was assisted by a surgical robot and a manual group ( n=12) in which the minimally invasive percutaneous pedicle screwing was performed manually. There were 8 males and 4 females in the robot group, aged from 35 to 74 years; there were 7 males and 5 females in the manual group, aged from 36 to 69 years. The clinical effects were evaluated by comparing the 2 groups in terms of operation time, fluoroscopy frequency, fluoroscopy time, intra-operative needle adjustments, intra-operative blood loss, screwing accuracy, and visual analogue scale (VAS) scores, anterior vertebral height ratios and sagittal cobb angles at preoperation, postoperative 3 days and the last follow-up. Results:There was no statistically significant difference in the preoperative general data between the 2 groups, showing comparability ( P>0.05). A total of 128 screws were implanted in the robot group and 126 ones in the manual group. In the robotic group, operation time [(129.2±10.5) min], fluoroscopy frequency [(8.5±2.1) times], fluoroscopy time [(9.8±1.9) s], guide needle adjustments [(2.3±1.4) times], and intraoperative blood loss [(65.3±9.8) mL] were significantly less than those in the manual group [(153.8±18.1) min, (39.8±5.1) times, (43.9±4.8) s, (18.6±2.6) times and (96.8±10.9) mL] (all P<0.05). Regarding the screwing accuracy evaluated using CT scanning, the robot group was significantly higher (93.75%, 120/128) than the manual group (84.92%, 107/126) ( P<0.05). There was no significant difference between the 2 groups in VAS score, anterior vertebral height ratio or sagittal cobb angle at postoperative 3 days or the last follow-up ( P>0.05). The VAS scores, anterior vertebral height ratios and sagittal cobb angles at postoperative 3 days and the last follow-up were significantly improved than the preoperative values in all patients ( P<0.05). There was no supplementary surgery or screw loosening in either of the 2 groups. Conclusion:In the treatment of multi-segmental thoracolumbar fractures, robot-assisted percutaneous pedicle screwing can achieve satisfactory clinical effects, because, compared with traditional open surgery, it has exhibited advantages of less operation time, lower radiation exposure, less intraoperative blood loss, and higher screwing accuracy.

Optimization and finite element analysis of a safe screw pathway in bilateral lumbo-iliac fixation / 中华创伤骨科杂志

Objective:To analyze the biomechanical characteristics of bilateral lumbo-iliac fixation by finite element analysis after digital optimization of a safe screw pathway.Methods:Firstly, a healthy adult male volunteer was recruited for this study who underwent CT scanning of the lumbus and pelvis, with a slice thickness of 0.625 mm.The original data were imported into Mimics 16.0 software for 3D lumbar and pelvic reconstruction.At the same time, a geometric screw pathway and a free screw pathway were generated in the pedicles of L4 and L5 and ilium.Secondly, all 3D models were imported into Ansys 12 software to assemble a finite element model.The displacements and von Misses stress distribution were measured in the conditions of forward bending, backward extending, lateral bending to the left and right, and left and right rotations in the models of 2 kinds of pathway after gravity axial load of 500 N was applied.Results:The models of 2 different pathways were similar in comprehensive displacement and stress in the conditions of forward bending, lateral bending and backward extending, and in the maximum stress of the screw in the conditions of forward bending and lateral bending.However, the comprehensive displacement and stress in the condition of rotation and the stress of the screw in the conditions of backward extending and rotating in the model of geometric screw pathway were obviously smaller than those in the model of free screw pathway.The maximum pelvic stress was on the screw surface between 190 and 260 MPa, concentrated on the bending area of the 2 screws connecting the sacrum and vertebral body.The lumbar-iliac fixation model showed high com-pressive stiffness.The maximum von Misses stress appeared in the L4-L5 pedicle screw on the longitudinal rod.Under rotational loading, the upper longitudinal rod connecting the L4-L5 pedicle screw and the iliac bone screw bore the maximum stress.Conclusions:Our finite element analysis shows that double verte-bral bodies and long screw fixation are effective ways of iliolumbar fixation.The geometric screw path optimized by digital analysis exhibits better fatigue resistance, rotation resistance and overall stability.Internal lum-bo-iliac fixation can effectively share the stress of vertebral bodies.

Computer-aided modification of Reverdin osteotomy template for hallux valgus / 中华创伤骨科杂志

Objective To provide a method to modify accurately the Reverdin osteotomy template for hallux valgus using 3D reconstruction and printing.Methods From June 2015 to June 2016,11 patients (16 feet) with hallux valgus at our departments underwent weight-bearing X-ray examination and continuous spiral CT scanning of the feet.The outer turning angle of hallux averaged 33.50° ± 6.80°,the first intermetatarsal angle 12.20°± 2.90° and the distal metatarsal articular angle 15.20°± 2.60°.Their imaging Dicom data were imported into Materialise Mimics Innovation Suite v16.0 software for generation of 3D models of the pelvis which were then stored in stereolithography format and imported into Imageware 12 software.After optimal templates were reversely rebuilt to have the best angles and range for Reverdin osteotomy in the 3D models,they were manufactured by a rapid prototyping machine.The osteotomy templates were used in surgery to guide the osteotomy of hallux valgus.Correction of hallux valgus,bone union at the osteotomy sites and weight-bearing walk were observed postoperatively.Results Accurate angles of osteotomy were confirmed by postoperative radiography in all the 16 feet.Follow-ups for 6 to 12 months showed in the 16 feet a mean outer turning angle of hallux of 7.31 °±0.33° (from 5° to 11 °) and a mean correction of 21.92°± 4.8° (from 13° to 24°).Bone union was fine at the osteotomy sites and no pain was reported during weight-bearing walk.Conclusion 3D reconstruction and printing can produce a patient-specific template for accurate Reverdin osteotomy for hallux valgus,leading to increased contact area and fine union of the osteotomy ends.

Digital analysis and certification of osseous pathway for anterograde screwing in acetabular posterior column / 中华创伤骨科杂志

Objective To analyze and determine the optimal osseous pathway for anterograde screwing in the acetabulum posterior column.Methods Recruited for this study were 40 healthy adult volunteers,20 nales and 20 females,aged from 18 to 56 years (average,34.6 years).Firstly,their abdomen CT scanning images were transformed into Materialise Mimics Innovation Suite 16.0 software to obtain the 3D reconstruction images of the pelvis (.stl file).The Imageware 12.0 software (EDS,USA) was used to produce the optimal osseous pathway for anterograde screwing in the acetabulum posterior column.The diameter and length of the pathway were measured and statistically analyzed.Secondly,after 10 adult fresh pelvic specimens were scanned,the optimal osseous pathway for anterograde screwing in the acetabulum posterior column was determined in the same way as the above.A navigation template for anterograde screwing in the acetabular posterior column was manufactured.The screwing in the posterior column of the acetabulum was conducted using Kirschner wire with the aid of the navigation template.Imaging evaluation was performed after fixation.Results The projection of the safe zone in the acetabular posterior column was irregularly triangle;there were no significant differences regarding the projection size between different ages (P ＞ 0.05).The maximum diameter and the maximum length of the left optimal pathway in males were respectively 22.37 ± 1.42 mm and 131.27 ± 3.63 mm,and those of the right optimal pathway in males respectively 23.16 ± 1.39 mm and 129.23 ± 3.27 mm.The maximum diameter and the maximum length of the left optimal pathway in females were respectively 17.58 ± 1.83 mm and 112.56 ±2.77 mm,and those of the right optimal pathway in females respectively 16.92 ± 1.66 mm and 114.41 ± 2.98 mm.There were no significant differences between the left and right sides for the same item in the same gender (P ＞ 0.05).There were significant differences between males and females for the same item in the same side (P ＜ 0.05).No penetration into the cortex or the hip joint happened.Conclusion The optimal osseous pathway for anterograde screwing in the acetabulum posterior column can be determined by digital techniques,leading to a simple and safe procedure for the treatment of fractures of the acetabular posterior column.

Evaluation of transverse percutaneous fixation with iliosacral screws via the second sacral vertebra for longitudinal sacral fractures / 中华创伤骨科杂志

Objective To explore the safe bone channels for transverse placement of sacroiliac screws via the second sacral vertebra in the fixation of longitudinal fracture of the sacrum by digital analysis and clinical observation.Methods Firstly,abdomen CT scanning was performed in 50 healthy adult volunteers.They were 30 males and 20 females,aged from 18 to 56 years (mean,34.6 years).After their CT images were transformed by software Materialise Mimics Innovation Suite 15.0,three-dimensional (3D) models of the pelvis were generated,stored in stereolithography format,and transferred into software Imageware 12.0.In the standard antero-posterior position,the sacrum was segmented and the points of 2D image coordinate geometric boundary were extracted to generate an optimal channel for transverse placement of sacroiliac screws via the second sacral vertebra.Secondly,we admitted 10 patients with longitudinal fracture of the sacrum.They were 7 men and 3 women,aged from 20 to 51 years (average,38.3 years).By Tile classification,4 cases were type B2 and 6 type C1.All the fractures were Denis region Ⅱ ones.Pubic ramus fracture was complicated in 3 cases.After traction reduction of the tibial tubercle was conducted for patients with obvious displacement,the optimal channel was calculated on the basis of the CT data.On the lateral images of the sacrum acquired before operation by C-arm fluoroscopy,the optimal channel for transverse placement of sacroiliac screws via the second sacral vertebra was located.After the skin was marked,2.5 mm Kirschner wire was drilled and the 6.0 mm hollow screws were fixated along the Kirschner wire.Postoperative CT scanning images and 3D reconstructed models were analyzed to validate the accuracy of screw placement.Results The projection of safety bone channel on the sagittal fluoroscopy of S2 vertebral body displayed an irregular water drop shape;the projection area in males (213.9 ± 52.4 mm2) was significantly larger than that in the females (171.6 ±49.6 mm2) (P ＜ 0.05).The average length of the channel in men (135.2 ± 12.9 mm) was significantly longer than that in women (121.1 ± 10.1 mm);the average diameter of the screw in men (10.2 ± 0.9 mm) was also significantly larger than that in women (9.1 ±0.8 mm) (P ＜ 0.05).The postoperative X-ray and CT scanning images showed satisfactory positions and lengths of the screws.The screw lengths averaged 98.2 mm;the operation time averaged 25.6 min.No nerve or vascular injury,loosening or breakage of the sacroiliac screws occurred in the patients.Follow-ups for 12 to 24 months revealed no other complications.Conclusion The safety channel for transverse placement of sacroiliac screws via the second sacral vertebra can be determined using the lateral 3D reconstruction images of the sacrum in preoperative planning,which facilitates the percutaneous transverse fixation of longitudinal fracture of the sacrum.

Finite element analysis on anterograde screw fix of anterior column of acetabulum / 中华骨科杂志

Objective To explore the optimal screw fixation of anterior column lag screw fixation in the treatment of acetabular anterior column fractures by finite element method.Methods Firstly,CT scanning images from one healthy adult volunteer (male 30),were transferred into Materialise Mimics Innovation Suite 16.0 software,then three-dimensional (3D) models of pelvic were reconstructed and stored in stereolithography format.Then Imageware 12.0 software (EDS,USA) was used to produce the optimal and safe channel of the screw for acetabulum anterior column fixation.Three types of screw fixation were generated,i.e.(1) geometric algorithm screw channel,(2) in-out-in channel,(3) free screw channel.Secondly,all model data were transferred into Ansys 12.0 software to establish the finite element model.Gravity load were defined as 600 N,1 200 N,and 2 400 N,and the Von Mises the parameters of peak stress and deformation were recorded.Results Respectively load of 600 N,1 200 N,2 400 N force to normal hip and geometric algorithm screw channel, in-out-inscrew channel,free screw channel,the comparison between groups of hip by stress and hip deformation,with a given loading force of hip by stress and hip deformation increase gradually,the two were positively correlated,including screw by stress at slightly higher than that of normal hip,while the stress of hip by geometric algorithm screw channel andin-out-inscrew channel were similar,and that by free screw channel increased significantly.There was no significant difference between groups in the hip deformation.With a given loading force (600 N,1 200 N,2 400 N) on geometric algorithm screw channel、 in-out-inscrew channel and free screw channel,the deformation is gradually increased,and there were positively correlated.With the stress on geometric algorithm screw channel,it was significantly reduced compared with the latter two,and in-out-in screw channel suffered the biggest stress.Conclusion Through the finite element analysis,the geometric algorithm screw channel can be used as a safe and effective way for acetabulum anterior column fracture.

Three-dimensional reconstruction of the anterior cruciate ligament insertions imprinted: A preliminary study / 中国医师杂志

Objective To provide accurate bone tunnel positioning reference for clinical individual anterior cruciate ligament (ACL) reconstruction by three-dimensional (3D) reconstruction of femoral and tibial original footprint of ACL.Methods Forty volunteers were selected for this study,including 20 males and 20 females,and aged 18 to 35 years old.3D CT scanning images of knee data were obtained.3D bone models of knee and footprint of ACL were reconstructed.On the 3D reconstruction models,the shape and position of original footprint of ACL were displayed.Statistical significance was compared for their difference.Results Femoral original footprint of ACL,long axis of footprint,distances to the distal margin of the articular cartilage (DDCM),distances to the posterior margin of the articular cartilage (DPCM),double bundle center distance,and tibial original footprint short axis of ACL were significantly different between genders (P ＜ 0.05).However,no significant difference was found between genders for tibial original footprint long axis of ACL (P ＞ 0.05).Conclusions The insertion mark shape and nature position of footprint of ACL could be observed by 3D reconstruction using CT scan images.

Clinical significance and change with age of cervical vertebral uncinate process and transverse process of teenagers / 局解手术学杂志

Objective To explore the uncinate-transverse hole spacing developmental patterns and aging characteristics by means of studying the teenagers aging from 6~20 years old,and provide the basis for image analysis of the treatment and prevention of cervical spondy-losis. Method the 66 adolescents without trauma nor problems of nervous system were selected to do thin spiral CT scan(0. 625 ~1. 25 mm) ,the range was C1 ~T1 . The original data in the form of DICOM are analyzed according to gender and age. Results There was no sig-nificant difference in gender and different sides. Overall,the physical development of human increases gradually with age and has some signifi-cant differences. Conclusion There exists a close relationship between cervical hook-transverse process and the incidence of vertebral artery type and nerve root type cervical spondylosis.

Accuracy of screw placement in child’s thoracic pedicle assisted by digital navigation template / 中国组织工程研究

BACKGROUND:Many scholars at home and abroad have already attempted to apply the technique of the internal fixation pedicle screw placement to cure children’s spinal injuries in recent years, because the children’s thoracic pedicle is more smal , anatomical structure variation is big and adjacent relationship is complicated, so the application of adult’s pedicle screw technology simply to children who was in a continuous growth and development can increase operation risk greatly. Above this, improving the accuracy of nailing and reducing error rate become keys for further development of cervical pedicle fixation. OBJECTIVE:To provide an individualized and accurate positioning method for screw placement in thoracic pedicle of children by computer aided design and rapid prototyping technology. METHODS:After computed tomography scan of four cases of child specimens, the original data were made for three-dimensional reconstruction by the software, then the specimens were randomly divided into two groups:one group used the traditional pedicle internal fixation method, and the other group, first created the individual navigation template using the principle of reverse engineering and rapid prototyping technology. The lumbar pedicle screws were put into the samples by the individual navigation template. The position of the pedicle screws was evaluated according to the computer tomography scan. RESULTS AND CONCLUSION:The accurate rate of screw placement of the traditional pedicle internal fixation method was 58%;and the accurate rate of screw placement of the individual digital navigation template method was 81%. The success rate was better than the traditional surgery group. Furthermore, chi square test showed that there was a significant difference between two groups (P<0.05). These findings suggested that there has a high accuracy of the screw placement in thoracic pedicle of children assisted by the individual navigation template, ful y reflects the principle of individualization of screw placement, and provides a new feasible method for accurate screw placement in thoracic pedicle of children.

Three-dimensional virtual reality imaging combined with two-dimensional ultrasound images for the visual evaluation of hip dysplasia in infants / 中国组织工程研究

BACKGROUND:Ultrasound has been widely used in developmental hip dysplasia screening in infants and young children, but there are significant differences among different inspection findings, even in the reexamination by the same examiner. Therefore, the accuracy of ultrasound imaging in the diagnosis is of insufficient evidence. OBJECTIVE:Through virtual reality three-dimensional reconstruction images showing the structure of acetabulum and femoral head space, to obtain a new parameter in order to enrich measurement standards of Graf ultrasonic diagnosis technology and to further improve the credibility of the diagnosis of developmental dysplasia of the hip. METHODS:Ten fresh cadaver specimens of Chinese infants were selected, including five males and five females. Two-dimensional ultrasonic method was employed for hip screening, and at the same time, multi-slice spiral CT was used for three-dimensional reconstruction fol owed by volume reconstruction and fitting of surface reconstruction to display the anatomic structure around the hip and to simulate Graf’s two-dimensional ultrasound method to measure a andβangles on three-dimensional virtual reality images. RESULTS AND CONCLUSION:As confirmed by three-dimensional reconstruction, Graf’s two-dimensional ultrasound could be used to measure a and angles, truly reflecting the development of bony and cartilaginous acetabulum. Graf’s two-dimensional ultrasound contributed to the proper evaluation of beonatal hip dysplasia, which can be used as a routine examination for developmental dysplasia of the hip. These indicate that to master Graf’s ultrasound technology and strictly grasp the evaluation standards for developmental dysplasia of the hip is the important guarantee for diagnosis of developmental dysplasia of the hip.

Synthesis, photostability and bioactivity of 2,3-cyclopropanated abscisic acid.

The plant hormone abscisic acid (ABA) plays a central role in the regulation of plant development and adaptation to environmental stress. The isomerization of ABA to the biologically inactive 2E-isomer by light considerably limits its applications in agricultural fields. To overcome this shortcoming, an ABA analogue, cis-2,3-cyclopropanated ABA, was synthesized, and its photostability and biological activities were investigated. This compound showed high photostability under UV light exposure, which was 4-fold higher than that of (±)-ABA. cis-2,3-cyclopropanated ABA exhibited high ABA-like activity, including the ability to effectively inhibit seed germination, seedling growth and stomatal movements of Arabidopsis. In some cases, its bioactivity approaches that of (±)-ABA. trans-2,3-cyclopropanated abscisic acid was also prepared, an isomer that was more photostable but which showed weak ABA-like activity.

Application of computer-aided osteotomy template design in treatment of developmental dysplasia of the hip with steel osteotomy / 南方医科大学学报

<p><b>OBJECTIVE</b>To provide an accurate method for osteotomy in the treatment of developmental dysplasia of the hip with steel osteotomy by three-dimensional reconstruction and Reverse Engineering technique.</p><p><b>METHODS</b>Between January 2011 and December 2012, 13 children with developmental dysplasia of the hip underwent steel osteotomy. 3D CT scan pelvic images were obtained and transferred via a DICOM network into a computer workstation to construct 3D models of the hip using Materialise Mimics 14.1 software in STL format. These models were imported into Imageware 12.0 software for steel osteotomy simulation until a stable hip was attained in the anatomical position for dislocation or subluxation of the hip in older children. The osteotomy navigational templates were designed according to the anatomical features after a stable hip was reconstructed. These navigational templates were manufactured using a rapid prototyping technique.</p><p><b>RESULTS</b>The reconstruction hips in these children show good matching property and acetabulum cover.</p><p><b>CONCLUSION</b>The computer-aided design of osteotomy template provides personalized and accurate solutions in the treatment of developmental dysplasia of the hip with steel osteotomy in older children.</p>

Clinical application of three-dimensional reconstruction of ilium bone flap / 中华创伤骨科杂志

Objective To discuss an initial clinical application of three-dimensional reconstruction of ilium bone flap. Methods From December 2006 to June 2008, bone defects of 6 patients with frac-tures of femoral shaft and tibia were repaired using vascularized iliac bone flap. After injection of contrast a-gent, CT scan was performed. Amira 4.0 Software was applied to reconstruct personalized three-dimensional structures of the iliac bone flap. The points, lines, and surfaces were marked in the personalized three-dimensional images reconstructed to provide guidance for the actual surgery. Results The person-alized three-dimensional reconstruction of iliac bone flap for the 6 individual patients were successfully used in the actual surgery. The three-dimensional structures of blood vessels, bone and adjacent relationship which had been clearly shown in the reconstructed flaps were confirmed by the actual surgical findings. All the 6 lilac bone flaps survived uneventfully. Conclusion The preoperative three-dimensional reconstruction of lilac bone flap by CT scan, angiography and digital technology can provide a useful aid for actual surgical design and harvest of the flap, minimizing intraoperative injury to blood vessels and enhancing flap survival.

Navigation template for sacral fracture fixation using three-dimensional reconstruction and reverse engineering technique / 中华创伤骨科杂志

Objective To provide a new method for sacral fracture fixation by means of 3D recon-struction and reverse engineering technique. Methods Pelvis images of 3D CT scan were obtained from patients with sacral fracture. The digital data were transferred into a computer workstation. 3D models of pelvis were reconstructed using Amira 3.1 software and saved in STL format. The 3D fracture models were imported into Imageware 10.0 software. Different situations of reduction (total reduction, half reduction and no-reduction) were simulated using Imageware 10.0 software. The extract locations and the best directions of inserting iliosacral lag screws were defined using Reverse Engineering according to the 3 situations to before navigation templates were designed according to the posterior anatomic features of the ilium and the insertion channels. Exact navi-gational templates were manufactured by rapid prototyping. Drill guides were sterilized and used intraoperatively to assist surgical navigation and placement of iliosacral lag screws. Results Accurate screw placement was confirmed with postoperative X-ray and CT scanning. The navigation templates were found to be helpful and highly accurate. Conclusion The navigation template may be a useful method for mini-invasive fixation of sacroiliac joint fracture.

Analysis of Nef-specific interferon-γ secretion responses in HIV-1 B/C recombinant virus infectors / 中华检验医学杂志

Objective To analyze characteristics of Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype B/C infectors. Methods 19 HIV-1 recombinant subtype B/C infectors infected within 1 year, 40 chronic infectors infected for more than 3 years were enrolled in this cohort study. Elispot assay was used to observe HIV-1 specific T lymphocyte responses in HIV-1 recombinant subtype B/C infectors. Results Nef-specific T lymphocyte responses of interferon-gamma secretion were identified in 15 Chinese HIV-1 recombinant subtype B/C infectors infected within 1 year. The specific T lymphocytes were mainly targeted at four peptides which span from Nef 83 to 135: EVA7081.1, EVAT081.5, EVA7081.6 and EVAT081.48. Responses were identified in 29(75. 2%) infectors with more than 3 years of infection and the specific T lymphocytes were mainly targeted at three peptides which span from Nef 63 to 101 : EVA7081.43, EVA7081.44, EVAT081.45, EVA7081.47, EVA7081.48 and EVA7081.49. The average magnitude of response in infectors with less than 1 year of infection was 284. 13 SFC/106 PBMC. The average magnitude of response in infectors with more than 3 years of infection was 152. 44 SFC/106 PBMC. There was a significant difference between the two groups (U = 91. 000, P = 0. 002). Conclusions HIV-1recombinant subtype B/C infectors at different stages of diseases (less than 1 year and more thank 3 years) can recognize central region of Nef. The magnitude of Nef-specific IFN-γ secretion T lymphocyte responses in this cohort gradually decrease with disease progression.

Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype C/B' and subtype B' in-fectors / 中华微生物学和免疫学杂志

Objective To analyze character of Nef-specific T lymphocyte responses in Chinese HIV-1 recombinant subtype C/B' and subtype B' infectors and to identify the common immunodominant re-gions recognized by these infectors. Methods Fifty-nine HIV-1 recombinant subtype C/B' infectors and 27 subtype B' infectors were tested by IFN-γ enzyme linked immunospot (ELISPOT) assay using HIV-1 C/B' Nef overlapping peptides. Results Nef-specific T-cell responses of IFN-γ secretion were identified in 44 (74.58%) out of 59 HIV-1 recombinant subtype C/B' infectors. Ten peptides, EVA7081.1,5, 6, 7,43, 44, 45, 47, 48, 49 were mainly recognized. Amino acid position was from Nef63 to 115 and 117 to 139. Twenty of 27 (74.07%) HIV-1 subtype B' infectors recognized peptides. EVA7081.1,2, 43 and 49 were mainly recognized. Amino acid position was from Nef 63 to 77 and 87 to 119. There was no correlation be-tween the Nef-specific IFN-production of HIV-1-specific T cells responses and viral load or CD4 T cell count in both subtype infectors. Conclusion The immunodominant regions, from Nef63 to 77 and 87 to 115 were recognized by both Chinese HIV-1 recombinant subtype C/B' infectors and subtype B' infectors. These re-gions could be used in design of vaccine.

Observation of the sectional anatomic structure of the double inferior vena cava and visualization of its main structures in the Virtual Chinese Human Male Ⅲ / 中国组织工程研究

BACKGROUND:Double inferior vena cava (DIVC), usually found at routine autopsies, is rare in the clinic. It has been described in numerous reports over the years since Adachi first depicted it in 1940. But all these reports were based on two-dimensional (2D) observation, and no three-dimensional and animated images reported. OBJECTIVE: To observe and establish the digital visible models of the structure of DIVC of the Virtual Chinese Human Male (VCH-M) Ⅲ.DESIGN: Repetitive measurement design by taking VCH-M Ⅲ as the subjects.SETTING : Department of Traumatic Orthopedics and Anatomy, Nanfang Hospital Affiliated to Southern Medical University.MATERIALS: The experiment was conducted in Southern Medical University from February 2006 to May 2006. The cross-sectional images of fresh tissues from VCH-M Ⅲ dataset were reviewed and 1 060 serially-sectioned slices of VCH-M Ⅲ, from the 2 600th slice to the 3 660th were taken as the source for the 3D models in our study.METHODS: Cross-sectional images of fresh tissues from the VCH-M Ⅲ dataset were reviewed and the structures of the DIVC were confirmed on a section-by-section basis. 3D computerized reconstructions of DIVC and its adjacent structures were generated from these data using Arnira 3.1 (TGS) imaging software.MAIN OUTCOME MEASURES: Cross-sectional images and 3D reconstruction of VCH-M Ⅲ.RESULTS: The cross-sectional images of the VGH-M Ⅲ could fairly display the main structure of DIVC. The digitized model of brachial plexus offers unique insights into the abnormity anatomy of DIVC.CONCLUSION: The VCH-M Ⅲ dataset can provide complete and accurate data of DIVC.

No mutation was detected in the LMNA gene among sporadic Charcot-Marie-Tooth patients / 北京大学学报(医学版)

Objective: To intensively investigate sporadic CMT patients, we have analyzed the LMNA gene in this study in a series of 32 unrelated CMT patients. Methods: Twelve exons of the LMNA gene were amplified from genetomic DNA. PCR products of each exon were analyzed by single strand conformational polymorphism (SSCP). Results: No abnormal SSCP pattern, suggesting no mutation in our CMT patients, was detected. Conclusion: The CMT diseases resulted from the mutations of LMNA gene were rare.