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Objective To establish the instability model of goat cervical vertebrae, and test biomechanical stability of the novel arc cervical titanium mesh with endplate ring. Methods The anatomical data from cervical vertebrae of adult goats were measured, so as to select a new type of arch cervical titanium mesh with endplate ring which was suitable for goat cervical vertebrae. A total of 24 goats with preserved articular capsule, ligaments and intervertebral disc were randomly divided into 4 groups. Group A (n=6, normal group) didn’t receive any special treatment, while Group B (n=6, model group) received partial resection of C4 vertebrae as well as upper and lower intervertebral disc. On the basis of models in Group B, Group C (n=6, experimental group) was installed with the novel arch cervical titanium mesh and fixed by plate and screw, and Group D (n=6,control group) was installed with traditional straight titanium mesh and fixed by plate and screw. The ranges of motion (ROMs) for 4 groups of specimens during flexion, extension, left/right lateral bending, left/right rotation under 2.0 N·m load were measured, and their three-dimensional (3D) motion stability was tested. The displacement of Group C and Group D under 200 N compression force was measured, the stiffness was calculated, and the anti settlement ability of the whole specimen was tested. Results The ROMs of Group A in all directions were smaller than those of Group B,the ROMs of Group A were larger than those of Group C, and the ROMs of Group C during flexion were smaller than those of Group D (P<0.05). The stiffness of Group C was higher than that of Group D (P<0.05).The compression displacement of Group C was smaller than that of Group D(P<0.05). Conclusions Compared with the straight titanium mesh, the novel arc titanium mesh is more consistent with the physiological curvature of cervical verebrae, and has better stability than the traditional titanium mesh during the most frequent flexion activities of cervical verebrae. Moreover, compression displacement of the novel arc titanium mesh under short-term stress is smaller than that of the straight titanium mesh, and its postoperative anti-settlement is better than that of the straight titanium mesh, which is worthy of further experiment and clinical promotion.
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BACKGROUND: The existing technique takes articular process and lateral mass as a reference mark. Due to differences of subjective judgment in operation and the impact of articular hyperplasia, some errors of screw entry point selection and serious complications such as vertebral artery or cervical spinal cord injury easily occurred, which limit the clinical application of the technique. At present, it is very important to select a constant reference mark of cervical pedicle screw entry point.OBJECTIVE: Three-dimensional reconstruction CT images were made to measure the relationship between the lower cervical pedicle screw entry point and the lateral concave between articular process.METHODS: Three-dimensional reconstruction of CT scan was performed in 30 patients with cervical deformity, and the occurrence rate and morphological characteristics of the lateral concave between articular process were observed. The following parameters were determined on specific reconstructed CT image of C3-C7: (1) the distance between pedicle axis projection point in the posterior surface and the outer edge of lateral mass in transversal section through bilateral pedicle axis and (2) the distance between the point and the lateral concave between articular process in oblique sagittal section through homolateral pedicle axis. Mean value and standard deviation were counted and statistics difference was compared.RESULTS AND CONCLUSION: (1) The lateral concave between articular process in lower cervical vertebrae was a obvious and less constant proliferative anatomical landmark and its occurrence rate was 100%. (2) Using CT technology of 3D reconstruction, C3-C7 lower cervical transversal section through bilateral pedicle axis and oblique sagittal section through homolateral pedicle axis were successfully obtained. (3) In transversal section, the left and right distances between C3-C7 pedicle axis projection point in the posterior surface and the outer edge of lateral mass were (4.1±0.9)mm and (4.3±0.9) mm, and the difference was not statistically significant (P=0.609). Except for C3 and C7, C4 and C7,there was no significant difference in the measured values of the same side (P > 0.05). (4) In oblique sagittal section, the left and right distances between C3-C7 point and the lateral concave between articular process were (-0.3±1.7) mm and (-0.3±1.6) mm, and the difference was not statistically significant (P=0.916). Except for C3 and C4, there was significant difference in the measured values of the same side (P < 0.05). (5) The above results suggest that the lower cervical pedicle entry point and the lateral concave between articular process have a relatively constant orientation relationship in transversal section and a large variation in the sagittal section.
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Objective:To observe the clinical effects of targeted percutanous ozone ablation on lumbar disc herniation (LDH) patients with high intensity zone (HIZ) in lumbar disc annulus fibrosus on MRI T2 weighted imaging.Methods:136 LDH patients with HIZ in lumbar disc annulus fibrosus on MRI T2 were divided into two groups according to therapy methods.In group A,75 patients were injected with 2 ～5 mL of 40 μg/mL mixture of O3 and O2 after targeted percutanous puncturing under the guidance of X-Ray machine with C-type arm.In group B,61 patients were treated with conservative treatment.MacNab score criterion and Oswestry disability index (ODI) were used in assessment of the efficacy.Results:Except 24 patients,all the other cases were followed up for 18 ～ 44 months.At the postoperative 1st,2nd,3rd,6th,9th,12th and 18th month,according to MacNab score criterion,the effective rates were respectively 88.00 ％,90.67 ％,93.33 ％,89.39 ％,84.85 ％,78.13 ％ and 73.44 ％ in group A and respectively 68.85 ％,62.30 ％ 55.74 ％,61.82 ％,58.12 ％,54.17 ％ and 47.92 ％ in group B.There were significant differences between two groups at the same time point (P＜0.05).At the postoperative 12th and 18th month,ODI was lower in group A,and there was no significant difference between two time points (P＞0.05).But it was significant different with that preoperatively and in group B at the same time point (P＜0.05).Conclusion:Targeted percutanous ozone ablation is an effective method with stable clinical efficacy in treating LDH with HIZ in lumbar disc annulus fibrosus on MRI T2 weighted imaging.
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Objective:To explore the imaging measurement and clinical significance of the angle between the axis ofpedicle and the plane of lamina in lower cervical vertebra.Methods:Three dimensional reconstruction of CT scan was performed in 30 patients with cervical deformity,and the angle between the axis ofpedicle and the plane of lamina was measured with the specific reconstructed CT image of C3-C7.Results:1) The left and right transverse angle of C3-C7 between the axis of pedicle and the ipsilateral plane oflamina were 98.3°±6.3°,98.0°±5.1°,97.5°±6.9°,95.1°±5.0°,85.8°±5.4°and 96.7°±8.2°,98.7°±7.1°,97.8°±3.6°,93.2° ±6.2°,86.8° ±5.7°,respectively,which showed a gradual decreasing trend.Meanwhile the angle ofC3-C6 was more than 90 degrees and C7 was less than 90 degrees.In addition to C6 with C3 and C7 with other segments,the rest of the differences between the sections was not statistically significant (all P＞0.05).2) The left and right transverse angle of C3-C7 between the axis of pedicle and the pedicle of vertebral arch of lamina were 0.2°±4.5°,1.2°±7.2°,-0.8° ±6.8°,-3.3°±5.4°,-14.7° ±4.0° and-1.6°±5.4°,1.9°±4.6°,-0.5° ±6.0°,-4.6° ±5.3°,-13.7°±3.4°,respectively,which showed a first increasing and then reducing trend.Meanwhile the angle of C4 was maximum angle.In addition to C6 with C3;C6 with C4,and C7 with other segments,the differences between the sections was not statistically significant (all P＞0.05).3) The left and right sagittal angle of C3-C7 between the axis of pedicle and the ipsilateral plane of lamina were 77.7°±7.6°,77.0°±7.1°,85.3° ±8.4°,94.1°±2.2°,94.9°±3.8° and 78.5° ±7.1°,76.2° ±6.2°,86.4°±6.4°,94.0°±2.7°,95.6°±3.8°,respectively,which showed a gradual increasing trend.The angle of C3-C4 was less than 90 degrees.Cs showed large variation and C6-C7 was more than 90 degrees.In addition to C3 with C4 and C6 with C7,the differences between the sections was statistically significant (all P＜0.05).There was no significant difference between the two sides of the above indexes (all P＞0.05).Conclusion:In low cervical vertebra,there is a certain angle relationship between the axis of pedicle and the plane of lamina,which can provide reference for the clinical determination of angle of pedicle screw insertion.
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Objective To observe the changes of calcitonin gene-related peptide(CGRP) -immunoreactive positive nerve fibers innervation in bone tissue of femoral heads during the pathological process of early steroid-induced avascular necrosis of the femoral head (SANFH), and explore its significance.Methpathological group of SANFH was induced.Immunohistochemical technique was used and the changes of CGRP-immunoreactive positive nerve fibers innervation in weight bearing area of the femoral heads during the pathological process of early SANFH were observed.Result The number of CGRP-immunoreactive nerves increased first and then decreased ( Peaked at 6 weeks, 10.28 ± 0.66 ), but it was more than that ofnormal control group.There was significant difference between two groups ( P ＜ 0.01 ).Conclusion There were changes in the distribution of CGRP-immunoreactive positive nerves fiber during the process of bone repair after SANFH.CGRP-immunoreactive positive nerves fiber might take part in the process of bone repair in SANFH.