Статті в журналах з теми "Vertebral axis"
Щоб переглянути інші типи публікацій з цієї теми, перейдіть за посиланням: Vertebral axis.
Оформте джерело за APA, MLA, Chicago, Harvard та іншими стилями
Ознайомтеся з топ-50 статей у журналах для дослідження на тему "Vertebral axis".
Біля кожної праці в переліку літератури доступна кнопка «Додати до бібліографії». Скористайтеся нею – і ми автоматично оформимо бібліографічне посилання на обрану працю в потрібному вам стилі цитування: APA, MLA, «Гарвард», «Чикаго», «Ванкувер» тощо.
Також ви можете завантажити повний текст наукової публікації у форматі «.pdf» та прочитати онлайн анотацію до роботи, якщо відповідні параметри наявні в метаданих.
Переглядайте статті в журналах для різних дисциплін та оформлюйте правильно вашу бібліографію.
1
Kaushal, Parul, and Subhash Bhukya. "Fusion of C2 and C3: embryological and clinical perspective." Anatomy Journal of Africa 7, no. 2 (September 19, 2018): 1281–83. http://dx.doi.org/10.4314/aja.v7i2.177636.
Анотація:
Skeletal abnormalities in the upper cervical region may result in severe neck ache, altered mobility, muscular weakness and sensory deficits. Fused cervical vertebrae (FCV) have been reported in literature, however cases with fused articular facets have scarcely been documented. During routine osteology demonstration, we came across fused axis and the 3rd cervical vertebra. There was complete fusion of the vertebral arch on the left side along with complete fusion between the inferior articular facet of C2 and superior articular facet of C3. There was partial fusion between the bodies of the vertebrae and the right half of the vertebral arch. Owing to the vital role of this region in various neck movements and spinal alignment, knowledge of such asymmetric variations in the upper cervical region, is of immense importance to orthopedicians, radiologists, neurosurgeons, anaesthetists, physiotherapists.Keywords: intubation, synostosis, axis, block vertebrae
2
Holt, C. A., S. L. Evans, D. Dillon, and S. Ahuja. "Three-Dimensional Measurement of Intervertebral Kinematics in Vitro Using Optical Motion Analysis." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 219, no. 6 (June 1, 2005): 393–99. http://dx.doi.org/10.1243/095441105x34374.
Анотація:
Measurement of the stiffness of spinal motion segments is widely used for evaluating the stability of spinal implant constructs. A three-dimensional motion analysis technique has been developed that allows accurate measurement of the relative movement of the vertebral bodies about a well-defined anatomical axis system. The position of marker clusters on each vertebra is tracked using digital infrared cameras (Qualisys AB, Gothenburg). Landmarks are identified using a marked pointer, and an anatomical coordinate system is defined for each vertebra. The transformation relating the upper and lower vertebrae is calculated, using the joint coordinate system approach of Grood and Suntay to find the rotations and translations in each anatomical plane. The stiffness of vertebrectomy constructs was investigated using a Synex vertebral body replacement and an anterior rod with one or two screws in each vertebral body, with or without damage to the posterior longitudinal ligament (PLL). A moment of 2 N m was applied about each anatomical axis, and the range of motion about each axis was calculated. The range of motion in flexion-extension and lateral bending was significantly greater with only one screw. When the PLL was cut, there was no significant increase in the range of motion.
3
Dhakal, Arun, P. Adhikari, N. Ranjit, and D. Budhathoki. "Morphometry of Dry Sub Axial Vertebra: A Nepalese Study." Nepal Medical College Journal 23, no. 1 (April 2, 2021): 48–54. http://dx.doi.org/10.3126/nmcj.v23i1.36228.
Анотація:
There is paucity in literature describing the morphology of sub-axial vertebra of the local population. Available studies are limited to the body, intervertebral disk, spinal canal and Torg’s ratio of the cervical vertebra. Therefore, the present study aims to document various morphological parameters of sub axial vertebra. Sixty-four dry sub-axial vertebrae of the Nepalese population were studied using Vernier Calipers calibrated to 0.1 mm accuracy. Paired parameters of pedicle, lamina, uncinate process, the distance of the apex of the uncinate process to intervertebral foramen and foramen transversarium were measured. Similarly, unpaired parameters including spinous process length, vertebral foramen anteroposterior width, vertebral foramen transverse diameter and Torg’s ratio were evaluated. Except the height of left lamina of C3 to C6 vertebrae, none of the parameters showed significant side differences. Significant higher values of C7 were noted against C3-C6 on vertebral body height, vertebral body anteroposterior diameter, spinous process length and vertebral foramen anteroposterior diameter. Population data of sub-axial vertebra available in literature showed mixed results with ours. Interestingly, our observations either compared to (lamina, uncinate process, anteroposterior diameter of spinal canal and Torg’s ratio) or were larger (Pedicle and spinous process) than the Indian study with pedicle axis length being largest among all the compared studies. The information of this study may be used as a reference database for our local setting and could be of value in preoperative planning and in designing implants.
4
Wong, Siew Fen Lisa, Vikram Agarwal, Jennifer H. Mansfield, Nicolas Denans, Matthew G. Schwartz, Haydn M. Prosser, Olivier Pourquié, David P. Bartel, Clifford J. Tabin, and Edwina McGlinn. "Independent regulation of vertebral number and vertebral identity by microRNA-196 paralogs." Proceedings of the National Academy of Sciences 112, no. 35 (August 17, 2015): E4884—E4893. http://dx.doi.org/10.1073/pnas.1512655112.
Анотація:
The Hox genes play a central role in patterning the embryonic anterior-to-posterior axis. An important function of Hox activity in vertebrates is the specification of different vertebral morphologies, with an additional role in axis elongation emerging. The miR-196 family of microRNAs (miRNAs) are predicted to extensively target Hox 3′ UTRs, although the full extent to which miR-196 regulates Hox expression dynamics and influences mammalian development remains to be elucidated. Here we used an extensive allelic series of mouse knockouts to show that the miR-196 family of miRNAs is essential both for properly patterning vertebral identity at different axial levels and for modulating the total number of vertebrae. All three miR-196 paralogs, 196a1, 196a2, and 196b, act redundantly to pattern the midthoracic region, whereas 196a2 and 196b have an additive role in controlling the number of rib-bearing vertebra and positioning of the sacrum. Independent of this, 196a1, 196a2, and 196b act redundantly to constrain total vertebral number. Loss of miR-196 leads to a collective up-regulation of numerous trunk Hox target genes with a concomitant delay in activation of caudal Hox genes, which are proposed to signal the end of axis extension. Additionally, we identified altered molecular signatures associated with the Wnt, Fgf, and Notch/segmentation pathways and demonstrate that miR-196 has the potential to regulate Wnt activity by multiple mechanisms. By feeding into, and thereby integrating, multiple genetic networks controlling vertebral number and identity, miR-196 is a critical player defining axial formulae.
5
Morin-Kensicki, Elizabeth M., Ellie Melancon, and Judith S. Eisen. "Segmental relationship between somites and vertebral column in zebrafish." Development 129, no. 16 (August 15, 2002): 3851–60. http://dx.doi.org/10.1242/dev.129.16.3851.
Анотація:
The segmental heritage of all vertebrates is evident in the character of the vertebral column. And yet, the extent to which direct translation of pattern from the somitic mesoderm and de novo cell and tissue interactions pattern the vertebral column remains a fundamental, unresolved issue. The elements of vertebral column pattern under debate include both segmental pattern and anteroposterior regional specificity. Understanding how vertebral segmentation and anteroposterior positional identity are patterned requires understanding vertebral column cellular and developmental biology. In this study, we characterized alignment of somites and vertebrae, distribution of individual sclerotome progeny along the anteroposterior axis and development of the axial skeleton in zebrafish. Our clonal analysis of zebrafish sclerotome shows that anterior and posterior somite domains are not lineage-restricted compartments with respect to distribution along the anteroposterior axis but support a ‘leaky’ resegmentation in development from somite to vertebral column. Alignment of somites with vertebrae suggests that the first two somites do not contribute to the vertebral column. Characterization of vertebral column development allowed examination of the relationship between vertebral formula and expression patterns of zebrafish Hox genes. Our results support co-localization of the anterior expression boundaries of zebrafish hoxc6 homologs with a cervical/thoracic transition and also suggest Hox-independent patterning of regionally specific posterior vertebrae.
6
Yanni, Daniel S., and Noel I. Perin. "Fixation of the Axis." Neurosurgery 66, suppl_3 (March 1, 2010): A147—A152. http://dx.doi.org/10.1227/01.neu.0000365743.16893.ea.
Анотація:
Abstract OBJECTIVE To review and compare the techniques of fixation of the axis vertebral segment. Also, to review the anatomy of the axis vertebrae, ligamentous attachments, and unique biomechanics of this segment. METHODS The use of wire, cable, screw, and plate fixation techniques are reviewed and discussed in the treatment of fractures of C1 and C2 along with utilization of the halo vest and cervical collar during the postoperative period. RESULTS All fixation methods were useful. However, the appropriate fixation technique is best determined by the local anatomy (eg, anomalous vertebral artery), posterior element fractures, or the necessity to remove the posterior elements for treatment of the underlying condition. CONCLUSION New techniques for fixation and instrumentation for fixation of the axis are available. Advanced imaging allows for advanced aggressive instrumentation while avoiding injury to adjacent structures. Biomechanical studies have influenced the utility and popularity of each technique.
7
Saba, N., A. Rani, G. Sehgal, Rk Verma, Ak Srivastava, and M. Faheem. "Fusion of axis with third cervical vertebra: a case report." Romanian Neurosurgery 30, no. 2 (June 1, 2016): 284–88. http://dx.doi.org/10.1515/romneu-2016-0044.
Анотація:
Abstract Introduction: Fusion of one or more contiguous vertebral segments is usually the result of embryological failure of normal spinal segmentation. It may be associated with syndromes such as Klippel-Feil. Fused cervical vertebrae (FCV) may also be acquired or pathologic. FCV is generally associated with disease like tuberculosis, other infections, juvenile rheumatoid arthritis and trauma. The commonest site of involvement is C2-C3. In condition of fusion the two vertebrae appear not only structurally as one but also function as one. This anomaly may be asymptomatic; however, it may also manifest in the form of serious clinical features such as myelopathy, limitation of the neck movement, muscular weakness, atrophy or neurological sensory loss. Case report: We observed the fusion of axis with 3rd cervical vertebra. Body, laminae and spines of C2 and C3 were completely fused on both anterior and posterior aspects, whereas the pedicles and transverse processes were not fused. Foramen transversarium was present on both the vertebrae bilaterally. Conclusion: This variation is noteworthy to neurosurgeons and radiologists in studying computed tomography (CT) and magnetic resonance imaging (MRI) scans.
8
Brink, Rob C., Jelle F. Homans, Tom P. C. Schlösser, Marijn van Stralen, Koen L. Vincken, Lin Shi, Winnie C. W. Chu, Max A. Viergever, René M. Castelein, and Jack C. Y. Cheng. "CT-based study of vertebral and intravertebral rotation in right thoracic adolescent idiopathic scoliosis." European Spine Journal 28, no. 12 (September 11, 2019): 3044–52. http://dx.doi.org/10.1007/s00586-019-06138-3.
Анотація:
Abstract Purpose To define the longitudinal rotation axis around which individual vertebrae rotate, and to establish the various extra- and intravertebral rotation patterns in thoracic adolescent idiopathic scoliosis (AIS) patients, for better understanding of the 3D development of the rotational deformity. Methods Seventy high-resolution CT scans from an existing database of thoracic AIS patients (Cobb angle: 46°–109°) were included to determine the vertebral axial rotation, rotation radius, intravertebral axial rotation, and local mechanical torsion for each spinal level, using previously validated image processing techniques. Results For all levels, the longitudinal rotation axis, from which the vertebrae rotate away from the midline, was localized posterior to the spine. The axis became closer to the spine at the apex: apex, r = 11.5 ± 5.1 cm versus two levels above (radius = 15.8 ± 8.5 cm; p < 0.001) and beneath (radius = 14.2 ± 8.2 cm; p < 0.001). The vertebral axial rotation, intravertebral axial rotation, and local mechanical torsion of the vertebral bodies were largest at the apex (21.9° ± 7.4°, 8.7° ± 13.5° and 3.0° ± 2.5°) and decreased toward the neutral, junctional zones (p < 0.001). Conclusion In AIS, the vertebrae rotate away around an axis that is localized posterior to the spine. The distance between this axis and the spine is minimal at the apex and increases gradually to the neutral zones. The vertebral axial rotation is accompanied by smaller amounts of intravertebral rotation and local mechanical torsion, which increases toward the apical region. The altered morphology and alignment are important for a better understanding of the 3D pathoanatomical development of AIS and better therapeutic planning for bracing and surgical intervention. Graphic abstract These slides can be retrieved under Electronic Supplementary Material.
9
Hirabayashi, Shigeru, and Kiyoshi Kumano. "FINITE ELEMENT ANALYSIS OF THE SPACE CREATED BY SPLIT SPINOUS PROCESSES IN DOUBLE-DOOR LAMINOPLASTY TO OPTIMIZE SHAPE OF AN ARTIFICIAL SPACER." Journal of Musculoskeletal Research 04, no. 01 (March 2000): 47–54. http://dx.doi.org/10.1142/s0218957700000070.
Анотація:
In double-door laminoplasty, several types of artificial spinous process spacers have been used instead of grafted bone from the iliac crest. However, inadequate contact between the spacer and the spinous process has recently been reported. From the observation during operation, we suspect that the main cause of the inadequate contact is the difference in shape between the spacer and the widened space created by the split spinous processes. The purpose of this study was to investigate the shape of the widened space by means of a finite element analysis in order to confirm our observation objectively and to provide a shape design of a spacer adapting to the space. Half-sectioned finite element models of the second cervical (C2) vertebra and the C6 vertebra were made from both the computed tomography (CT) of a clinical case and a plastic model of a cervical spine. The finite element model was designed to have almost the same size and shape as those of the genuine vertebra in the clinical case. Since cancellous bone and soft tissues were thought not to meaningfully influence the rigidity of the model, the model was made of only cortical bone with a thickness of 1.5 mm. The x-axis was defined as the lateral direction of the vertebral body, the y-axis as the anteroposterior direction of the vertebral body and the z-axis as the craniocaudal direction along the posterior margin of the vertebral body. The boundary conditions were fixed at the inner surface of the half-sectioned vertebral body. A force of 100 N was applied to the inner surface of the half-sectioned spinous process (to the cranial side and the caudal side, 50 N each) in the direction of the x-axis. The lateral deviation of each split spinous process was defined as the degree of deviation in the x-axis direction. The degree of lateral deviation of each split spinous process was analyzed in two types of models with and without making a lateral gutter 4 mm wide along the z-axis direction. The lateral deviation at the cranial side was larger than that at the caudal side in both the C2 and C6 vertebrae. The difference between the lateral deviation at the cranial side and the caudal side of each vertebra was larger in the type of model with the lateral gutter than in the type of model without it. It was confirmed that the shape of the widened space is trapezoidal in not only the axial but also frontal sections. In conclusion, the optimal shape of a spacer adapting to the widened space in double-door laminoplasty is trapezoidal in not only the axial but also frontal sections.
10
Kaur, Jasveen, Mamta Sharma, Poonam Singh, and Ajay Kumar. "MORPHOMETRY OF THE VERTEBRAL CANAL OF ATLAS AND AXIS." International Journal of Anatomy and Research 5, no. 4.3 (December 1, 2017): 4711–15. http://dx.doi.org/10.16965/ijar.2017.454.
11
Matyushin, I. F., and S. N. Tsybusov. "Aetiology and mechanism of spinal compression fractures." Kazan medical journal 68, no. 1 (February 15, 1987): 48–50. http://dx.doi.org/10.17816/kazmj95903.
Анотація:
We identify 5 etiological factors of vertebral compression fractures, which individually are probabilistic and together lead to a fracture: impact force action on the vertebral body, suddenness of force action, position of the spine bending at the moment of force action, orientation of force action along the spinal axis, and exceeding the individual strength limit of the vertebra.
12
Ge, Weiqing, Dong-Yuan Cao, Cynthia R. Long, and Joel G. Pickar. "Plane of vertebral movement eliciting muscle lengthening history in the low back influences the decrease in muscle spindle responsiveness of the cat." Journal of Applied Physiology 111, no. 6 (December 2011): 1735–43. http://dx.doi.org/10.1152/japplphysiol.00059.2011.
Анотація:
Proprioceptive feedback is thought to play a significant role in controlling both lumbopelvic and intervertebral orientations. In the lumbar spine, a vertebra's positional history along the dorsal-ventral axis has been shown to alter the position, movement, and velocity sensitivity of muscle spindles in the multifidus and longissimus muscles. These effects appear due to muscle history. Because spinal motion segments have up to 6 degrees of freedom for movement, we were interested in whether the axis along which the history is applied differentially affects paraspinal muscle spindles. We tested the null hypothesis that the loading axis, which creates a vertebra's positional history, has no effect on a lumbar muscle spindle's subsequent response to vertebral position or movement. Identical displacements were applied along three orthogonal axes directly at the L6 spinous process using a feedback motor system under displacement control. Single-unit nerve activity was recorded from 60 muscle spindle afferents in teased filaments from L6 dorsal rootlets innervating intact longissimus or multifidus muscles of deeply anesthetized cats. Muscle lengthening histories along the caudal-cranial and dorsal-ventral axis, compared with the left-right axis, produced significantly greater reductions in spindle responses to vertebral position and movement. The spinal anatomy suggested that the effect of a lengthening history is greatest when that history had occurred along an axis lying within the anatomical plane of the facet joint. Speculation is made that the interaction between normal spinal mechanics and the inherent thixotropic property of muscle spindles poses a challenge for feedback and feedforward motor control of the lumbar spine.
13
Danowitz, Melinda, Aleksandr Vasilyev, Victoria Kortlandt, and Nikos Solounias. "Fossil evidence and stages of elongation of the Giraffa camelopardalis neck." Royal Society Open Science 2, no. 10 (October 2015): 150393. http://dx.doi.org/10.1098/rsos.150393.
Анотація:
Several evolutionary theories have been proposed to explain the adaptation of the long giraffe neck; however, few studies examine the fossil cervical vertebrae. We incorporate extinct giraffids, and the okapi and giraffe cervical vertebral specimens in a comprehensive analysis of the anatomy and elongation of the neck. We establish and evaluate 20 character states that relate to general, cranial and caudal vertebral lengthening, and calculate a length-to-width ratio to measure the relative slenderness of the vertebrae. Our sample includes cervical vertebrae ( n =71) of 11 taxa representing all seven subfamilies. We also perform a computational comparison of the C3 of Samotherium and Giraffa camelopardalis , which demonstrates that cervical elongation occurs disproportionately along the cranial–caudal vertebral axis. Using the morphological characters and calculated ratios, we propose stages in cervical lengthening, which are supported by the mathematical transformations using fossil and extant specimens. We find that cervical elongation is anisometric and unexpectedly precedes Giraffidae. Within the family, cranial vertebral elongation is the first lengthening stage observed followed by caudal vertebral elongation, which accounts for the extremely long neck of the giraffe.
14
Bogduk, N., B. Amevo, and M. Pearcy. "A Biological Basis for Instantaneous Centres of Rotation of the Vertebral Column." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 209, no. 3 (September 1995): 177–83. http://dx.doi.org/10.1243/pime_proc_1995_209_341_02.
Анотація:
The instantaneous centre of rotation has proven to be a useful parameter of vertebral motion. The normal location of instantaneous centres has been determined in cadavers and in normal volunteers for the cervical, thoracic and lumbar spines, and abnormal location of centres has been shown to correlate with spinal pain. However, to date, an instantaneous centre has constituted no more than a convenient mathematical summary of vertebral kinematics. It has defied resolution into biologically meaningful parameters. This study offers a novel model of vertebral motion in which the instantaneous centre of rotation can be shown to be a function of the location of the centre of reaction of a vertebra, and the intrinsic rotation and translation it undergoes. These parameters are strictly linked by equations that determine the location of an axis of rotation. These equations allow aberrations in the location of an axis to be interpreted in terms of the anatomical and pathological factors that affect the centre of reaction of the vertebra and the rotation and translation it undergoes.
15
Hubner, André Rafael, Carlos Tobias Scortegagna, Charles Leonardo Israel, Everton Luis do Amarante Ivo, Fabiano Favretto, Marcelo Ribeiro, and Leandro de Freitas Spinelli. "NEW PROPOSAL FOR THE TREATMENT OF CORONAL SPLIT FRACTURES IN LUMBAR VERTEBRAE: THE FATIGUE CURVE." Coluna/Columna 20, no. 2 (June 2021): 127–31. http://dx.doi.org/10.1590/s1808-185120212002235745.
Анотація:
ABSTRACT Objective: To evaluate a new treatment for split fractures through fatigue tests on a swine model. Methods: Thirty lumbar spine samples (L2-L3-L4) from swine models were divided into three test groups. The first was the control group (intact vertebrae). In the second group, a bone defect was created, similar to a coronal split fracture of the vertebral body. For this, a bone defect (osteotomy) was performed in the coronal axis of the middle third of the middle lumbar vertebral body (L3), keeping the disc-ligament structures intact. In the third group, the same procedure was performed to cause bone failure, but was associated with the use of synthesis material, with pedicular fixation using 3.5 mm cannulated screws with partial thread, in order to apply compression at the fracture site, giving resistance and support to the vertebra. The groups were submitted to biomechanical fatigue tests. The number of cycles required to failure in the specimen was analyzed. Results: The use of the synthesis material increased the resistance of the fractured vertebrae to levels equal to those of the intact vertebra for low cycles with loads of 40% of the failure load, possibly losing up to 20% of their resistance for higher cycles. Conclusions: In the vertebrae in which synthetic material was used, greater resistance to a greater number of cycles for a longer period of time was observed when compared with the fractured vertebrae, suggesting that this is an interesting method for the fixation of split-type spinal fractures. Level of evidence III; Experimental Study.
16
Madawi, A. Abou, G. Solanki, A. T. H. Casey, and H. A. Crockard. "VARIATION OF THE GROOVE IN THE AXIS VERTEBRA FOR THE VERTEBRAL ARTERY." Journal of Bone and Joint Surgery. British volume 79-B, no. 5 (September 1997): 820–23. http://dx.doi.org/10.1302/0301-620x.79b5.0790820.
17
Patkar, Sushil. "Posterior atlantoaxial fixation with new subfacetal axis screw trajectory avoiding vertebral artery with customized variable screw placement plate and screws to enhance biomechanics of fixation." Neurosurgical Focus: Video 3, no. 1 (July 2020): V10. http://dx.doi.org/10.3171/2020.4.focusvid.20168.
Анотація:
Fixation for atlantoaxial dislocation is a challenging issue, and posterior C1 lateral mass and C2 pars–pedicle screw plate–rod construct is the standard of care for atlantoaxial instability. However, vertebral artery injury remains a potential complication. Recent literature has focused on intraoperative navigation, the O-arm, 3D printing, and recently use of robots for perfecting the trajectory and screw position to avoid disastrous injury to the vertebral artery and enhance the rigidity of fixation. These technological advances increase the costs of the surgery and are available only in select centers in the developed world.Review of the axis bone anatomy and study of the stress lines caused by weight transmission reveal that the bone below the articular surface of the superior facet is consistently dense as it lies along the line of weight transmission A new trajectory for the axis screw 3–5 mm below the midpoint of the facet joint and directed downward and medially avoids the course of the vertebral artery and holds the axis rigidly. Divergent screw constructs are biomechanically stronger. Variable screw placement (VSP) plates with long shaft screws permit manipulation of the vertebrae and realignment of the facets to the correct reduced position with fixation in the compression mode.The video can be found here: https://youtu.be/E1msiKjM-aA
18
Goel, Atul, Ranjit Rangnekar, Abhidha Shah, Survendra Rai, and Ravikiran Vutha. "Mobilization of the Vertebral Artery—Surgical Option for C2 Screw Fixation in Cases With “High Riding” Vertebral Artery." Operative Neurosurgery 18, no. 6 (September 25, 2019): 648–51. http://dx.doi.org/10.1093/ons/opz289.
Анотація:
Abstract BACKGROUND Mobilization of intraosseous course of vertebral artery for safe screw insertion into pedicle of axis in cases with high riding vertebral artery is discussed. OBJECTIVE To show drilling, exposure, and mobilization of the “high-riding” vertebral artery loop during its course in relationship with superior facet/pedicle of C2 vertebra can provide safety to techniques of atlantoaxial fixation that involve insertion of screws in the pars/pedicle/facet of C2. METHODS During the period June 2016 to April 2018, 15 patients operated for atlantoaxial stabilization underwent vertebral artery exposure and mobilization using the technique discussed. The ages of the patients ranged from 6 to 48 yrs. Four patients had mobile and reducible atlantoaxial dislocation. Seven patients had basilar invagination. Four patients had os-odontoideum. Gentle and precise drilling of bone that covers the “high-riding” vertebral artery can lead to its safe and wide surgical exposure. The arterial loop can then be either completely or partially mobilized out of the vertebral artery groove such that C2 screw insertion can be conducted under direct surgical visualization of the vertebral artery. RESULTS During the average follow-up period of 14 mo, there have been no complications related to the surgical procedure, metal implant, or vertebral artery. CONCLUSION Vertebral artery exposure and mobilization is rather simple and safe procedure and is remarkably effective in providing a space for C2 screw implantation.
19
van den Akker, Eric, Sylvie Forlani, Kallayanee Chawengsaksophak, Wim de Graaff, Felix Beck, Barbara I. Meyer, and Jacqueline Deschamps. "Cdx1andCdx2have overlapping functions in anteroposterior patterning and posterior axis elongation." Development 129, no. 9 (May 1, 2002): 2181–93. http://dx.doi.org/10.1242/dev.129.9.2181.
Анотація:
Mouse Cdx and Hox genes presumably evolved from genes on a common ancestor cluster involved in anteroposterior patterning. Drosophila caudal (cad) is involved in specifying the posterior end of the early embryo, and is essential for patterning tissues derived from the most caudal segment, the analia. Two of the three mouse Cdx paralogues, Cdx 1 and Cdx2, are expressed early in a Hox-like manner in the three germ layers. In the nascent paraxial mesoderm, both genes are expressed in cells contributing first to the most rostral, and then to progressively more caudal parts of the vertebral column. Later, expression regresses from the anterior sclerotomes, and is only maintained for Cdx1 in the dorsal part of the somites, and for both genes in the tail bud. Cdx1 null mutants show anterior homeosis of upper cervical and thoracic vertebrae. Cdx2-null embryos die before gastrulation, and Cdx2 heterozygotes display anterior transformations of lower cervical and thoracic vertebrae. We have analysed the genetic interactions between Cdx1 and Cdx2 in compound mutants. Combining mutant alleles for both genes gives rise to anterior homeotic transformations along a more extensive length of the vertebral column than do single mutations. The most severely affected Cdx1 null/Cdx2 heterozygous mice display a posterior shift of their cranio-cervical, cervico-thoracic, thoraco-lumbar, lumbo-sacral and sacro-caudal transitions. The effects of the mutations in Cdx1 and Cdx2 were co-operative in severity, and a more extensive posterior shift of the expression of three Hox genes was observed in double mutants. The alteration in Hox expression boundaries occurred early. We conclude that both Cdx genes cooperate at early stages in instructing the vertebral progenitors all along the axis, at least in part by setting the rostral expression boundaries of Hox genes. In addition, Cdx mutants transiently exhibit alterations in the extent of Hox expression domains in the spinal cord, reminding of the strong effects of overexpressing Cdx genes on Hox gene expression in the neurectoderm. Phenotypical alterations in the peripheral nervous system were observed at mid-gestation stages. Strikingly, the altered phenotype at caudal levels included a posterior truncation of the tail, mildly affecting Cdx2 heterozygotes, but more severely affecting Cdx1/Cdx2 double heterozygotes and Cdx1 null/Cdx2 heterozygotes. Mutations in Cdx1 and Cdx2 therefore also interfere with axis elongation in a cooperative way. The function of Cdx genes in morphogenetic processes during gastrulation and tail bud extension, and their relationship with the Hox genes are discussed in the light of available data in Amphioxus, C. elegans, Drosophila and mice.
20
Cheema, Omer Iqbal, Muhammad Tajammal Butt, Tayyab Shoaib, Faiza Irshad, Muhammad Saad Abdullah, Mufassar Nishat, and Muhammad Afzal Khan. "Transpedicular Screw Fixation of the Lumbar Spine: an anatomical perspective." Pakistan Journal of Medical and Health Sciences 16, no. 2 (February 26, 2022): 231–34. http://dx.doi.org/10.53350/pjmhs22162231.
Анотація:
Background Transpedicular screw fixation of the lumbar spine is a popular procedure to attain stability in degenerative conditions, deformity and fracture. An inappropriate size and positioning of the screw however may result in postoperative neurological and vascular complications in up to 42% of cases emphasizing need for precise morphometric data. Aim: This study aimed at providing morphometric features of lumbar vertebral pedicles germane to transpedicular screw fixation in Punjab. Study design: Cross-sectional population study Methods: Lumbar spine measurements of height and transverse diameter of pedicles along with sagittal and transverse angles were recorded from CT scans of 33 adult males and 28 females using ImageJ1.47v radiological image processor. Distance along pedicular and sagittal axes reaching anterior cortex of vertebra (screw length) was also measured. Results: Vertical and transverse diameters of the pedicle were significantly larger in the male. Gradual increase from L1 to L5 in the sagittal and transverse angles was observed in both sexes. Both angles were comparatively larger in the females; transvers angle being much wider than the males. Depth (screw length) of anterior cortex along pediclular axis except at level L3 and parallel to sagittal axis was not significantly different in the two groups. Conclusion: The study has provided useful gender specific data which will be of interest to the researcher and may be useful for the operating surgeon in his preoperative assessment and deliberations of lumbar transpedicular screw fixation. Keywords: Lumbar spine, transpedicular screw fixation, morphometry, lumbar pedicle, lumbar vertebrae, Multan
21
Ozoner, Baris, Ahmet Kayhan, Nil Comunoglu, Seckin Aydin, Galip Zihni Sanus, and Necmettin Tanriover. "Chondrosarcoma in the body of the C2 vertebral axis." Journal of the American Academy of Physician Assistants 33, no. 11 (November 2020): 29–31. http://dx.doi.org/10.1097/01.jaa.0000718280.57597.60.
22
PELKER, RICHARD R., and GARY S. DORFMAN. "Fracture of the Axis Associated with Vertebral Artery Injury." Spine 11, no. 6 (July 1986): 621–23. http://dx.doi.org/10.1097/00007632-198607000-00015.
23
Abdel-Malek, K., D. P. McGowan, V. K. Goel, D. Kowalski, and S. B. Smith. "Bone registration method for robot assisted surgery: Pedicle screw insertion." Proceedings of the Institution of Mechanical Engineers, Part H: Journal of Engineering in Medicine 211, no. 3 (March 1, 1997): 221–33. http://dx.doi.org/10.1243/0954411971534331.
Анотація:
A registration method that identifies bone geometry with respect to a robotic manipulator arm is presented. Although the method is generally applicable to many orthopaedic internal fixation procedures, it was only demonstrated for the insertion of pedicle screws in vertebral bodies for spine fixation. The method relies upon obtaining an impression of the vertebral bodies. Computerized tomography (CT) scans of both vertebrae and mould are reconstructed using a computer aided engineering (CAE) system. From the reconstructions, the surgeon is able to do preoperative planning including selection of pedicle screw diameter, direction of screw through pedicle, point of entry and length of engagement. The three-dimensional models are then meshed to determine positions of the surgeon's preoperative plan relative to the mould. Intra-operative positions are defined in space by a mechanical fixture rigidly attached to the mould and designed to allow a manipulator end-effector to recognize the global coordinates of the in vivo spine. The theory and methodology were validated using a five-axis manipulator arm. This initial presentation assumes and allows no relative motion between vertebrae in vivo.
24
Olude, Matthew Ayokunle, Oluwaseun Ahmed Mustapha, Temitope Kehinde Ogunbunmi, and James Olukayode Olopade. "The Vertebral Column, Ribs, and Sternum of the African Giant Rat (Cricetomys gambianusWaterhouse)." Scientific World Journal 2013 (2013): 1–5. http://dx.doi.org/10.1155/2013/973537.
Анотація:
Examined bones were obtained from eight adult African giant rats,Cricetomys gambianusWaterhouse. Animals used had an average body mass of730.00±41.91 gm and body length of67.20±0.05 cm. The vertebral formula was found to be C7, T13, L6, S4, Ca31–36. The lowest and highest points of the cervicothoracic curvature were at C5and T2, respectively. The spinous process of the axis was the largest in the cervical group while others were sharp and pointed. The greatest diameter of the vertebral canal was at the atlas (0.8 cm) and the lowest at the caudal sacral bones (2 mm). The diameter of the vertebral foramen was the largest at C1and the smallest at the S4; the foramina were negligibly indistinct caudal to the sacral vertebrae. There were 13 pairs of ribs. The first seven pairs were sternal, and six pairs were asternal of which the last 2-3 pairs were floating ribs. The sternum was composed of deltoid-shaped manubrium sterni, four sternebrae, and a slender processus xiphoideus. No sex-related differences were observed. The vertebral column is adapted for strong muscular attachment and actions helping the rodent suited for speed, agility, dexterity, and strength which might enable it to overpower prey and escape predation.
25
Pintar, F. A., N. Yoganandan, M. Pesigan, J. Reinartz, A. Sances, and J. F. Cusick. "Cervical Vertebral Strain Measurements Under Axial and Eccentric Loading." Journal of Biomechanical Engineering 117, no. 4 (November 1, 1995): 474–78. http://dx.doi.org/10.1115/1.2794210.
Анотація:
The mid to lower cervical spine is a common site for compression related injury. In the present study, we determined the patterns of localized strain distribution in the anterior aspect of the vertebral body and in the lateral masses of lower cervical three-segment units. Miniature strain gages were mounted to human cadaveric vertebrae. Each preparation was line-loaded using a knife-edge oriented in the coronal plane that was moved incrementally from anterior to posterior to induce compression-flexion or compression-extension loading. Uniform compressive loading and failure runs were also conducted. Failure tests indicated strain shifting to “restabilize” the preparation after failure of a component. Under these various compressive loading vectors, the location which resulted in the least amount of deformation for a given force application (i.e., stiffest axis) was quantified to be in the region between 0.5–1.0 cm anterior to the posterior longitudinal ligament. The location in which line-loading produced no rotation (i.e., balance point) was in this region; it was also close to where the vertebral body strains change from compressive to tensile. Strain values from line loading in this region produced similar strains as recorded under uniform compressive loading, and this was also the region of minimum strain. The region of minimum strain was also more pronounced under higher magnitudes of loading, suggesting that as the maximum load carrying capacity is reached the stiffest axis becomes more well defined.
26
Orel, A. M. "Types of the statics of the spine in patients of young, elderly and senile age." Russian Osteopathic Journal, no. 1-2 (June 6, 2020): 38–48. http://dx.doi.org/10.32885/2220-0975-2020-1-2-38-48.
Анотація:
Introduction. A complete and systematic x-ray examination of all parts of the spine at the same time in elderly and senile people has not yet been carried out. On the other hand, radiography can identify spinal statics disorders that are typical for this category of people.The goal of research — describe the types of spinal statics disorders in young, elderly and senile people.Materials and methods. Digital radiography of all parts of the spine was performed in 103 patients with dorsopathies. The first group included 50 patients aged 60–74 years; men 16, women 34. The second study group included 21 patients aged 75–88 years, 6 men and 15 women. The third control group included 32 randomly selected people aged 21 to 45 years, 15 men and 17 women. The study belongs to the group of a posteriori x-ray processing and was carried out without the participation and additional irradiation of patients. On the screen of a personal computer, using the methods developed by the author, unified digital x-ray images of all parts of the spine of each patient were obtained. From the INION point, a vertical line occipital vertical descended along all the structures of the spine. Using the midpoint of the front and rear contour x-ray image of the vertebral body of the TII and TXII the front-rear axes were passed through until they intersect with the occipital vertical at the back and intersect with each other at the front. A qualitative assessment of the occipital vertical passage relative to the structures of the spine and a quantitative assessment of the angles of inclination and the angle of intersection of the front-rear axes of the TII and TXII vertebrae was carried out..Results. Five types (from 0 to 4) of spine statics were described and criteria for their qualitative and quantitative assessment were determined. It was found that in the control group, the most common type of spine statics was zero (0), while type 3 and 4 were not determined. In contrast, 3 and 4 types of spinal statics were most frequently observed in second group of patients. In the first group of patients, types 1 and 2 of spine statics were most often revealed, and other types of spine statics also occurred. Among the entire group of examined patients n=103 0 type of spinal statics disorder was detected in 27 (26,2 %) patients, type 1 in 35 (34 %), type 2 in 22 (21,3 %), type 3 in 11 (10,7 %) and type 4 in 8 patients (7,8 %). In patients with type 0 spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 16,67±8,49º, and of the TXII vertebra was 18,33±4,33º. In type 1 statics of the spine, the angle of inclination of the front-rear axis of the TII vertebra was 26,66±6,73º, and of the TXII vertebra was 21,17±4,92º. In type 2 spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 32,95± 6,82º, and of the TXII vertebra was 19,68±5,4º. In type III spinal statics, the angle of inclination of the front-rear axis of the TII vertebra was 41,09±9,22º, and of the TXII vertebra 26±11,05º. Type 4 statics of the spine were diagnosed in the presence of type 1–3 statics, in addition to which a pathological fracture or multiple compression fractures were detected in any part of the spine, or the vertebral bodies took the form of fish vertebrae.Conclusion. The study demonstrated the presence of characteristic prevailing types of spinal statics in young, elderly and senile people. These qualitative and quantitative criteria allow us to evaluate them. Based on the results of the study, an application for the utility patent of the Russian Federation «The Method for Evaluating Spine Statics», № 2019144992, priority dated 30.12.2019 was issued and filed. The identified qualitative and quantitative indicators can be used to develop criteria for determining the biological age of a person, which will contribute to improving the evidence-based approach to medicine.
27
Noor Chughtai, Waqas, Muhammad Adeel Razzaque, Tanveer Ahmad, Sumera Nighat, Rahila Tahir, and Bashir Ahmad. "Computerized Tomographic Based Study of Thoracic Spine Morphology in Relevance to Pedicle Screw Fixation in Pakistani Population." Pakistan Journal Of Neurological Surgery 25, no. 2 (June 14, 2021): 199–206. http://dx.doi.org/10.36552/pjns.v25i2.518.
Анотація:
Objective: To study the thoracic spine anatomy for accurate placement of pedicle screws using computerized tomography.
Material and Methods: CT scans of 200 patients were included in our study. T1 to T12 vertebrae morphology was studied for each patient. Following measurements were taken, 1: Transverse pedicle width, 2 = Depth of anterior cortex along pedicle axis, 3 = Transverse pedicle angle, 4 = canal dimensions, 5 = vertebral body height anterior and posterior, 6 = mid vertebral body width.
Results: Transverse pedicle width decreased from T1 (4.06 ± 0.50 mm) to T4 (3.72 ± 0.17 mm) and then gradually increases to T12 (6.08 ± 0.60 mm). Depth of the anterior vertebral cortex remained constant from T1 to T4 and gradually increases up to T12. Transverse pedicle angle remained constant from T1 to T4 with a maximum at T4 (23.39 ± 3.15 mm) and then gradually decreased to T12 (3.99 ± 2.16 mm). Anteroposterior (AP) canal dimensions were minimum at T7 (17.03 ± 1.01 mm) and maximum at T2 (21.2 ± 1.07 mm). Interpedicular (IPD) canal dimensions were minimum at T6 (19.18 ± 1.6 mm) and maximum at T3 (23.18 ± 1.2 mm). Anterior vertebral body height was minimum at T1 (16.9 ± 1.34 mm) and maximum at T12 (27.14 ± 1.34mm). Posterior vertebral body height was minimum at T1 (18.8 ± 1.13 mm) and maximum at T12 (29.76 ± 1.43 mm).
Conclusion: A detailed anatomy of the thoracic spine is essential for surgical planning to decrease postoperative complications.
28
Johnston, Marc, Shawn Ranieri, and William De Wit. "Proposal of a new method for treating type II odontoid fractures: Odontoid process prosthetic (Ti)." SURG Journal 1, no. 2 (February 13, 2008): 49–56. http://dx.doi.org/10.21083/surg.v1i2.408.
Анотація:
A novel method for treating type II odontoid fractures is presented. The use of a sintered titanium odontoid prosthetic could eliminate long healing times associated with external fixation methods, and the neurological deficits associated with non-union events in odontoid fracture treatment. Finite element experiments provide early indications that the axis vertebral body could accommodate a titanium odontoid prosthetic. Strain of 3.5 % and stresses of up to 10.5 MPa on the reamed opening of the axis vertebral body are considered as the local maximums. Conventional and emerging implant fixation and non-fouling techniques are also discussed.
29
Stangenberg, Martin, Lennart Viezens, Sven O. Eicker, Malte Mohme, Klaus C. Mende, and Marc Dreimann. "Cervical vertebroplasty for osteolytic metastases as a minimally invasive therapeutic option in oncological surgery: outcome in 14 cases." Neurosurgical Focus 43, no. 2 (August 2017): E3. http://dx.doi.org/10.3171/2017.5.focus17175.
Анотація:
OBJECTIVEThe treatment of cervical spinal metastases represents a controversial issue regarding the type, extent, and invasiveness of interventions. In the lumbar and thoracic spine, kypho- and vertebroplasties have been established as minimally invasive procedures for patients with metastases to the vertebral bodies and without neurological deficit. These procedures show good results with respect to pain reduction and low complication rates. However, limited data are available for kypho- and vertebroplasties for cervical spinal metastases. In an effort to add to existing data, the authors here present a case series of 14 patients who were treated for osteolytic metastases of the cervical spine using vertebroplasty alone or in addition to another surgical procedure involving the cervical spine in a palliative setting to reduce pain and restore stability.METHODSFourteen patients consisting of 8 males and 6 females, with a mean age of 64.7 years (range 44–85 years), were treated with vertebroplasty at the authors’ clinic between January 2015 and November 2016. In total, 25 vertebrae were treated with vertebroplasty: 10 C-2, 5 C-3, 2 C-4, 2 C-5, 3 C-6, and 3 C-7. Two patients had an additional posterior stabilization and 5 patients an additional anterior stabilization. In 13 cases, the surgical approach was a modified Smith-Robinson approach; in 1 case, the cement was injected into the corpus axis from posteriorly. Patients with osteolytic defects of the posterior wall of the vertebral body did not undergo surgery, nor did patients with neurological deficits. Preoperatively, on the 2nd day after surgery, and at the follow-up, neck pain was rated using the visual analog scale (VAS).RESULTSTwelve patients were examined at follow-up (mean 9 months). Neck pain was rated as a mean of 6.0 (range 3–8) preoperatively, 2.9 on Day 2 after surgery (range 0–5), and 0.5 at the follow-up (range 0–4), according to the VAS. The mean Neck Disability Index at follow-up was 3.6% (range 0%–18%).CONCLUSIONSAnterior vertebroplasty of the cervical spine via an anterolateral approach represents a safe and minimally invasive procedure with a low complication rate and appears suitable for reducing pain and restoring stability in cases of cervical spinal metastases. Vertebroplasties can be combined with other anterior and posterior operations of the cervical spine and, in the axis vertebra, can be performed transpedicularly from posteriorly. Thus, in cases in which the posterior wall of the vertebral body is intact, vertebroplasty represents a less invasive alternative to vertebral replacement in oncological surgery. Prospective randomized trials with a longer follow-up period and a larger patient cohort are needed to confirm the encouraging results of this case series.
30
Kessel, M. "Respecification of vertebral identities by retinoic acid." Development 115, no. 2 (June 1, 1992): 487–501. http://dx.doi.org/10.1242/dev.115.2.487.
Анотація:
In higher vertebrates, the formation of the body axis proceeds in a craniocaudal direction during gastrulation. Cell biological evidence suggests that mesoderm formation and specification of axial positions occur simultaneously. Exposure of gastrulating embryos to retinoic acid induces changes in axial patterns, e.g. anterior and posterior homeotic transformations of vertebrae. These morphological changes are accompanied by changes in the nonidentical, overlapping expression domains of Hox genes. In this report the influence of retinoic acid, administered at the end of and after gastrulation, on vertebral patterns is described. Anterior transformations and truncations affecting the caudal part of the vertebral column characterize animals exposed on day 8 and 9. 4 hours after retinoic acid administration on day 8 + 5 hours, Hox-1.8, Hox-1.9, and Hox-4.5 transcripts were not detected in their usual posterior expression domains, whereas transcripts of the anterior Hox-1.5 gene remained unaffected. 4 days after RA exposure on day 8 + 5 hours, Hox-1.8 expression was shifted posteriorly by an effectively low dose of RA, which induced the formation of supernumerary ribs. Hox-1.8 expression was limited to posterior, disorganized mesenchyme, bulging out neural tube, some intestinal loops and the hindlimb in truncated embryos exposed to a high dose of RA. A causal relation between the delayed activation of posterior Hox genes and anterior transformations or agenesis of vertebrae is discussed. On day 10.5 posterior transformations begin to occur in the cervical region, while later exposures again affect more caudal structures. The distribution of the transformations along the vertebral column indicates an influence of RA on migrating sclerotome cells before they are finally fixed in the cartilagenous vertebrae. The findings show that the mesodermal segments originally specified during gastrulation can be respecified in their second migratory phase, with effects spreading for a second time in a craniocaudal direction. The transformations are discussed with regard to a molecular specification of axial levels by Hox codes, defined as combinations of expressed Hox genes.
31
Luger, Allison M., Peter J. Watson, Hugo Dutel, Michael J. Fagan, Luc Van Hoorebeke, Anthony Herrel, and Dominique Adriaens. "Regional Patterning in Tail Vertebral Form and Function in Chameleons (Chamaeleo calyptratus)." Integrative and Comparative Biology 61, no. 2 (June 10, 2021): 455–63. http://dx.doi.org/10.1093/icb/icab125.
Анотація:
Synopsis Previous studies have focused on documenting shape variation in the caudal vertebrae in chameleons underlying prehensile tail function. The goal of this study was to test the impact of this variation on tail function using multibody dynamic analysis (MDA). First, observations from dissections and 3D reconstructions generated from contrast-enhanced µCT scans were used to document regional variation in arrangement of the caudal muscles along the antero-posterior axis. Using MDA, we then tested the effect of vertebral shape geometry on biomechanical function. To address this question, four different MDA models were built: those with a distal vertebral shape and with either a distal or proximal musculature, and reciprocally the proximal vertebral shape with either the proximal or distal musculature. For each muscle configuration, we calculated the force required in each muscle group for the muscle force to balance an arbitrary external force applied to the model. The results showed that the models with a distal-type of musculature are the most efficient, regardless of vertebral shape. Our models also showed that the m. ilio-caudalis pars dorsalis is least efficient when combining the proximal vertebral shape and distal musculature, highlighting the importance of the length of the transverse process in combination with the lever-moment arm onto which muscle force is exerted. This initial model inevitably has a number of simplifications and assumptions, however its purpose is not to predict in vivo forces, but instead reveals the importance of vertebral shape and muscular arrangement on the total force the tail can generate, thus providing a better understanding of the biomechanical significance of the regional variations on tail grasping performance in chameleons.
32
Fornell Muñoz, Alejandro, and Francisco Guerrero. "Mediterranean Basin Wetlands as a Vertebral Axis of the Territory." Nature and Culture 14, no. 1 (March 1, 2019): 61–78. http://dx.doi.org/10.3167/nc.2019.140104.
Анотація:
Within the framework of the new environmental history, this article focuses on the interaction between historical human societies and a given natural environment. Specifically, we study the spatial relationships between wetlands, Roman roads, and contemporary livestock trails, with the aim of verifying the role of wetlands as a support of territory planning since antiquity to the present. The documentation used includes geographical and ecological manuscripts together with ancient sources (texts, archaeology). Our results demonstrate an overlapping that remarks the importance of wetlands in the study area’s territorial ordering during various historical moments. This result also opens the possibility of applying this reality to others parts of the Mediterranean region with the same climatological conditions and a similar history. The clear heritage value of the wetlands are compelling enough to take the necessary protection measures for their conservation in the face of the growing threat of their deterioration and disappearance.
33
Kang, Ho Suck, Ji Won Kim, Byoung Young Choi, Byung Pil Cho, Tae Sun Hwang, and Ki Seok Koh. "Tortuosity of Vertebral Artery between the Atlas and the Axis." Korean Journal of Physical Anthropology 15, no. 2 (2002): 109. http://dx.doi.org/10.11637/kjpa.2002.15.2.109.
34
Kimura, K., M. Yasaka, H. Moriyasu, T. Tsuchiya, and T. Yamaguchi. "Ultrasonographic evaluation of vertebral artery to detect vertebrobasilar axis occlusion." Stroke 25, no. 5 (May 1994): 1006–9. http://dx.doi.org/10.1161/01.str.25.5.1006.
35
Howarth, Samuel J., Tyson A. C. Beach, and Jack P. Callaghan. "Abdominal Muscles Dominate Contributions to Vertebral Joint Stiffness during the Push-up." Journal of Applied Biomechanics 24, no. 2 (May 2008): 130–39. http://dx.doi.org/10.1123/jab.24.2.130.
Анотація:
The goal of this study was to quantify the relative contributions of each muscle group surrounding the spine to vertebral joint rotational stiffness (VJRS) during the push-up exercise. Upper-body kinematics, three-dimensional hand forces and lumbar spine postures, and 14 channels (bilaterally from rectus abdominis, external oblique, internal oblique, latissimus dorsi, thoracic erector spinae, lumbar erector spinae, and multifidus) of trunk electromyographic (EMG) activity were collected from 11 males and used as inputs to a biomechanical model that determined the individual contributions of 10 muscle groups surrounding the lumbar spine to VJRS at five lumbar vertebral joints (L1-L2 to L5-S1). On average, the abdominal muscles contributed 64.32 ± 8.50%, 86.55 ± 1.13%, and 83.84 ± 1.95% to VJRS about the flexion/extension, lateral bend, and axial twist axes, respectively. Rectus abdominis contributed 43.16 ± 3.44% to VJRS about the flexion/extension axis at each lumbar joint, and external oblique and internal oblique, respectively contributed 52.61 ± 7.73% and 62.13 ± 8.71% to VJRS about the lateral bend and axial twist axes, respectively, at all lumbar joints with the exception of L5-S1. Owing to changes in moment arm length, the external oblique and internal oblique, respectively contributed 55.89% and 50.01% to VJRS about the axial twist and lateral bend axes at L5-S1. Transversus abdominis, multifidus, and the spine extensors contributed minimally to VJRS during the push-up exercise. The push-up challenges the abdominal musculature to maintain VJRS. The orientation of the abdominal muscles suggests that each muscle primarily controls the rotational stiffness about a single axis.
36
Fromental-Ramain, C., X. Warot, S. Lakkaraju, B. Favier, H. Haack, C. Birling, A. Dierich, P. Doll e, and P. Chambon. "Specific and redundant functions of the paralogous Hoxa-9 and Hoxd-9 genes in forelimb and axial skeleton patterning." Development 122, no. 2 (February 1, 1996): 461–72. http://dx.doi.org/10.1242/dev.122.2.461.
Анотація:
Using gene targeting, we have produced mice with a disruption of Hoxa-9 or Hoxd-9, two paralogous Abdominal B-related genes. During embryogenesis, these genes are expressed in limb buds and along the vertebral axis with anterior expression boundaries at the level of prevertebra #20 for Hoxa-9 and #23 for Hoxd-9. Skeletal analysis revealed homeotic transformations corresponding to anteriorisations of vertebrae #21 to #25 (L1 to L5) in the lumbar region of Hoxa-9−/− mutants; vertebrae #23 to #25 (L3 to L5) in the lumbar region together with vertebrae #28, #30 and #31 (S2, S4 and Ca1) in the sacrum and tail were anteriorized in Hoxd-9−/− mutants. Thus, anteriorisation of vertebrae #23 to #25 were common to both phenotypes. Subtle forelimb (but not hindlimb) defects, corresponding to a reduction of the humerus length and malformation of its deltoid crest, were also observed in Hoxd-9−/−, but not in Hoxa-9−/−, mutant mice. By intercrosses between these two lines of mutant mice, we have produced Hoxa-9/Hoxd-9 double mutants which exhibit synergistic limb and axial malformations consisting of: (i) an increase of penetrance and expressivity of abnormalities present in the single mutants, and (ii) novel limb alterations at the level of the forelimb stylopod and additional axial skeleton transformations. These observations demonstrate that the two paralogous genes Hoxa-9 and Hoxd-9 have both specific and redundant functions in lumbosacral axial skeleton patterning and in limb morphogenesis at the stylopodal level. Taken all together, the present and previously reported results show that disruption of different Hox genes can produce similar vertebral transformations, thus supporting a combinatorial code model for specification of vertebral identity by Hox genes.
37
Fox, Mark W., David G. Piepgras, and John D. Bartleson. "Anterolateral decompression of the atlantoaxial vertebral artery for symptomatic positional occlusion of the vertebral artery." Journal of Neurosurgery 83, no. 4 (October 1995): 737–40. http://dx.doi.org/10.3171/jns.1995.83.4.0737.
Анотація:
✓ A case of repeated vertebrobasilar ischemic attacks related to head rotation (bow hunter's stroke) is reported. With head rotation of 45° or more to the right, the patient would become lightheaded and feel as if she were going to lose consciousness. Angiography performed when head rotation was to the right revealed mechanical compression of the left vertebral artery at the foramen transversarium of the axis and an occluded right vertebral artery. Untethering of the vertebral artery as it passed through the foramen transversarium of the atlas in this case completely relieved the patient's symptoms. The authors conclude that contralateral vertebral artery occlusion predisposed this patient to symptomatic vertebrobasilar insufficiency secondary to ipsilateral vertebral artery mechanical stenosis induced by head turning.
38
Coleman, Roger, Deed Harrison, Tim Fischer, and Sanghak O. Harrison. "Correlation and quantification of relative 2-dimensional projected vertebral endplate z-axis rotations with 3-dimensional y-axis vertebral rotations and focal spot elevations." Journal of Manipulative and Physiological Therapeutics 23, no. 6 (July 2000): 414–19. http://dx.doi.org/10.1067/mmt.2000.108141.
39
Singh, Dharmendra Kumar, Anuradha Sharma, Tankeshwar Boruah, Nishith Kumar, Saurabh Suman, and Binita Jaiswal. "Computed Tomography-Guided Vertebral Biopsy in Suspected Tuberculous Spondylodiscitis: Comparing a New Navigational Tram-Track Technique versus Conventional Method." Journal of Clinical Interventional Radiology ISVIR 4, no. 03 (December 2020): 159–66. http://dx.doi.org/10.1055/s-0040-1721532.
Анотація:
Abstract Introduction Computed tomography (CT)-guided vertebral biopsy is always recommended for histopathological and microbiological confirmation in cases of tuberculous spondylodiscitis and for antimycobacterial drug sensitivity testing. Aim To compare the conventional technique and a novel axis-defined tram-track technique of CT-guided vertebral biopsy in suspected tuberculous spondylodiscitis. Materials and Methods Sixty-seven patients of clinico-radiologically suspected tuberculous spondylodiscitis referred for CT-guided vertebral biopsy were categorized into two groups: “Group A” patients (n = 32) underwent biopsy by conventional technique, and “Group B” patients (n = 35) by axis-defined tram-track technique. The time taken for procedure, radiation exposure, and any procedural complications were recorded for both the groups. Results A statistically significant difference in procedure time and mean radiation dose was observed between the two groups: a longer procedural time was required in “Group A” (52.5 ± 3.5 minutes) as compared to “Group B” (37.3 ± 3.6 minutes) (p < 0.0001); and mean radiation dose (CTDIvol) in “Group A” and “Group B” was 8.64 ± 1.06 mGy and 5.73 ± 0.71 mGy, respectively (p < 0.0001). However, the difference in complication rate and tissue yield for successful diagnosis of the biopsies in the two groups was found to be statistically insignificant. Conclusion Axis-defined tram-track technique was found to have a significantly shorter procedural time as well as lower radiation exposure compared to the conventional technique of vertebral biopsy in our study.
40
Hiari, Asem, Bassam Nawaiseh, and Hesham Jaber. "Magneticresonance imaging in the diagnosis of vertebral haemangiomas." Eastern Mediterranean Health Journal 4, no. 1 (January 15, 1998): 149–55. http://dx.doi.org/10.26719/1998.4.1.149.
Анотація:
A retrospective analysis of 600 [238 females, 362 males] spine examinations was carried out. Vertebral haemangioma was observed in 160 patients [27%], 74 females [31%] and 86 males [24%]. The majority were over 35 years. The most frequent site was the lumbar region, 64 patients [40%], then the thoracic region, 32 patients [20%], cervical region, 26 patients [16%], predominantly in the dense complex of the axis, and 38 patients [24%] were found to have multiple haemangiomas. Characteristically all vertebral haemangiomas abutted or included the basivertebral veins in the vertebral body
41
Baker, Ruth E., Santiago Schnell, and Philip K. Maini. "Formation of Vertebral Precursors: Past Models and Future Predictions." Journal of Theoretical Medicine 5, no. 1 (2003): 23–35. http://dx.doi.org/10.1080/10273660310001628365.
Анотація:
Disruption of normal vertebral development results from abnormal formation and segmentation of the vertebral precursors, called somites. Somitogenesis, the sequential formation of a periodic pattern along the antero-posterior axis of vertebrate embryos, is one of the most obvious examples of the segmental patterning processes that take place during embryogenesis and also one of the major unresolved events in developmental biology. We review the most popular models of somite formation: Cooke and Zeeman's clock and wavefront model, Meinhardt's reaction-diffusion model and the cell cycle model of Stern and co-workers, and discuss the consistency of each in the light of recent experimental findings concerning FGF-8 signalling in the presomitic mesoderm (PSM). We present an extension of the cell cycle model to take account of this new experimental evidence, which shows the existence of a determination front whose position in the PSM is controlled by FGF-8 signalling, and which controls the ability of cells to become competent to segment. We conclude that it is, at this stage, perhaps erroneous to favour one of these models over the others.
42
Fonteque, Joandes Henrique, Anderson Fernando De Souza, Thiago Rinaldi Muller, Ronaldo Paiva Moreno Gonçalves, Milena Carol Sbrussi Granella, Rubens Peres Mendes, and Jackson Schade. "Congenital Cervical Vertebral Malformation in Lambs." Acta Scientiae Veterinariae 46 (March 21, 2018): 5. http://dx.doi.org/10.22456/1679-9216.86287.
Анотація:
Background: The occurrence of congenital defects in the sheep is estimated to be between 0.2% and 2%. For congenital anatomical alterations, diagnostic imaging allows objective understanding and evaluation, and is a great aid in the formulation of clinical decisions. Most of these anomalies are diagnosed by radiography; but computed tomography (CT) can provide important additional information. In the current literature there are no descriptions of the use of radiography andCT for a more detailed evaluation of the anatomical structures in cases of congenital cervical malformations in lambs. The objective of this study is to report the clinical, radiographic and tomographic findings in two cases of congenital cervical vertebral malformation in lambs.Cases: Two lambs with cervical morphological alterations since birth were attended. A 4-month-old mixed-breed lamb, weighing 11 kg, with lateroventrocaudal deviation of the neck was observed to the right side, not yielding to the attempt of repositioning. The owner reported that these changes were identified since birth, leading to difficulties in suckling colostrum, necessitating artificial feeding. With the growth of the animal, worsening of the cervical deviation resulted in the impossibility of grazing. The radiographs of the cervical spine identified marked scoliosis, and the axis presented small dimensions and morphological changes with a slight loss of atlantoaxial articular relationship. Spondylopathies were detectedalong the cervical spine. Other lamb of the Lacaune breed, weighing 4.2 kg, was presented shortly after birth with changes in the shape and posture of the neck, difficult locomotion and in sternal decubitus. The owner reported that the lamb came from a twin eutocic birth, with the other lamb being apparently normal. The animal was unable to ingest the colostrum, in which the sheep was milked and colostrum was offered through a bottle. Lateroventrocaudal deviation of the neck to the left side did not yield to the repositioning attempt, the mandible also presented left lateral deviation. The radiographs of the cervical spine showed morphological changes in atlas, and it was not possible to delimit its wings; itwas also observed that the dorsal blade was parallel to the spinal process of the axis. The presence of a hypoattenuating linear left lateral image of the dorsal arch and a right ventro-lateral aspect of the atlas body was identified with slightly irregular and sclerotic margins, suggesting fracture lines. The body of the axis presented a conformational alteration withirregular contours and a large free fragment in the cranial aspect, suggestive of being the odontoid process, with rotation and deviation to the left in relation to the atlas. The right lateral cranial articular process of the third cervical vertebra (C3) presented a conformational change and important lateral rotation of the axis. Mild stenosis of the medullary canal was observed in the segment adjacent to C3. The euthanasia was recommended.Discussion: Congenital cervical malformations in sheep are rare in the literature and may lead to serious decrease in the quality of life of the animals. Computed tomography was superior to radiography in morphological evaluation in cases of congenital cervical malformations in sheep. However, both diagnostic methods were important to establish the best clinical behavior. The etiology of most congenital malformations is unknown, simply because of the complexity of the mechanismsthat lead to the formation of an abnormality. The isolated episodes of this anomaly, in the herd without previous alterations, suggest a non-infectious cause, probably similar among the cases, but not established. The information presented can be used to validate clinical reasoning in future cases similar to those described, where imaging features are not available.Keywords: anomalies, fetus, radiography, computed tomography.
43
Aoyama, H., and K. Asamoto. "Determination of somite cells: independence of cell differentiation and morphogenesis." Development 104, no. 1 (September 1, 1988): 15–28. http://dx.doi.org/10.1242/dev.104.1.15.
Анотація:
Somites are mesodermal structures which appear transiently in vertebrates in the course of their development. Cells situated ventromedially in a somite differentiate into the sclerotome, which gives rise to cartilage, while the other part of the somite differentiates into dermomyotome which gives rise to muscle and dermis. The sclerotome is further divided into a rostral half, where neural crest cells settle and motor nerves grow, and a caudal half. To find out when these axes are determined and how they rule later development, especially the morphogenesis of cartilage derived from the somites, we transplanted the newly formed three caudal somites of 2.5-day-old quail embryos into chick embryos of about the same age, with reversal of some axes. The results were summarized as follows. (1) When transplantation reversed only the dorsoventral axis, one day after the operation the two caudal somites gave rise to normal dermomyotomes and sclerotomes, while the most rostral somite gave rise to a sclerotome abnormally situated just beneath ectoderm. These results suggest that the dorsoventral axis was not determined when the somites were formed, but began to be determined about three hours after their formation. (2) When the transplantation reversed only the rostrocaudal axis, two days after the operation the rudiments of dorsal root ganglia were formed at the caudal (originally rostral) halves of the transplanted sclerotomes. The rostrocaudal axis of the somites had therefore been determined when the somites were formed. (3) When the transplantation reversed both the dorsoventral and the rostrocaudal axes, two days after the operation, sclerotomes derived from the prospective dermomyotomal region of the somites were shown to keep their original rostrocaudal axis, judging from the position of the rudiments of ganglia. Combined with results 1 and 2, this suggested that the fate of the sclerotomal cells along the rostrocaudal axis was determined previously and independently of the determination of somite cell differentiation into dermomyotome and sclerotome. (4) In the 9.5-day-old chimeric embryos with rostrocaudally reversed somites, the morphology of vertebrae and ribs derived from the explanted somites were reversed along the rostrocaudal axis. The morphology of cartilage derived from the somites was shown to be determined intrinsically in the somites by the time these were formed from the segmental plate. The rostrocaudal pattern of the vertebral column is therefore controlled by factors intrinsic to the somitic mesoderm, and not by interactions between this mesoderm and the notochord and/or neural tube, arising after segmentation.
44
Kao, Fu-Cheng, Yu-Jui Huang, Ping-Yeh Chiu, Ming-Kai Hsieh, and Tsung-Ting Tsai. "Factors Predicting the Surgical Risk of Osteoporotic Vertebral Compression Fractures." Journal of Clinical Medicine 8, no. 4 (April 12, 2019): 501. http://dx.doi.org/10.3390/jcm8040501.
Анотація:
The aim of our study was to investigate the association between global spinal alignment, spinopelvic parameters, and outcomes of osteoporotic vertebral compression fractures (OVCF). Patients with vertebral compression fractures seen at our hospital between October 2017 and November of 2018 with a bone mineral density (BMD) T-score < −2.5 were recruited for the study. Surgical intervention was performed after eight weeks of conservative treatment depending on clinical symptoms and the willingness of patients. Spinopelvic and sagittal alignment parameters were compared between patients who had surgery and those that did not. Seventy-nine patients were included in the study. Twenty-five patients (31.6%, mean age: 73.28 ± 9.78 years) received surgery, and 54 (68.3%, mean age: 73 ± 8.58 years) conservative treatment only. Pelvic tilt, pelvic incidence, and local kyphotic angle were statistically different between the groups (all p < 0.05). A sagittal vertical axis ≥ 50 mm, distance between the C7 plumb line and the center of the fractured vertebra (DSVA) ≥ 60 mm, pelvic incidence outside of the range of 44 to 62°), and pelvic tilt ≥ 27° were associted with the need for surgical intervention. Measurement of spinopelvic parameters can predict the need for surgery in patients with OVCF.
45
Kaplan, Metin, Omer Hepgunsel, Selman Kok, and Murat Gonen. "Foramen Magnum Meningioma Presenting with Cough Syncope (Case Report and Review of the Literature)." Arquivos Brasileiros de Neurocirurgia: Brazilian Neurosurgery 37, no. 04 (December 2018): 334–38. http://dx.doi.org/10.1055/s-0038-1676532.
Анотація:
AbstractForamen magnum meningiomas cause different symptoms based on the size and the location of the tumor. They often present with involvement of the long tracts and of the lower cranial nerves. Ataxia and occipitocervical headache are other common symptoms. In the present study, we report a case of foramen magnum meningioma presenting with cough syncope. A mass lesion located anterolateral to the foramen magnum was detected in a 38-year-old man during a magnetic resonance imaging (MRI) exam; the lesion extended from the inferior clivus to the level of the C2 vertebra. The neural axis has pushed towards posterior and contralateral side by the mass. We think that syncope occurred due to the encasement of the vertebral arteries by the tumor in addition to the compression of the neural axis. The posterolateral approach without condylar resection provides a safe surgical plane for total excision of these tumors. In our case, the tumor was totally removed and the syncope episodes were resolved.
46
Fusaro, M., A. D’Angelo, G. Scalzo, M. Gallieni, S. Giannini, and G. Guglielmi. "Vertebral fractures in dialysis: Endocrinological disruption of the bone-kidney axis." Journal of Endocrinological Investigation 33, no. 5 (May 2010): 347–52. http://dx.doi.org/10.1007/bf03346598.
47
WOOD, KIRKHAM B., ENSOR E. TRANSFELDT, JAMES W. OGILVIE, MICHAEL J. SCHENDEL, and DAVID S. BRADFORD. "Rotational Changes of the Vertebral-Pelvic Axis Following Cotrel-Dubousset Instrumentation." Spine 16, Supplement (August 1991): S409. http://dx.doi.org/10.1097/00007632-199108001-00019.
48
Parmentier, E., D. Lecchini, and P. Vandewalle. "Remodelling of the vertebral axis during metamorphic shrinkage in the pearlfish." Journal of Fish Biology 64, no. 1 (January 2004): 159–69. http://dx.doi.org/10.1111/j.1095-8649.2004.00294.x.
49
Grünwald, Alexander T. D., Susmita Roy, Ana Alves-Pinto, and Renée Lampe. "Assessment of adolescent idiopathic scoliosis from body scanner image by finite element simulations." PLOS ONE 16, no. 2 (February 10, 2021): e0243736. http://dx.doi.org/10.1371/journal.pone.0243736.
Анотація:
Adolescent idiopathic scoliosis, is a three-dimensional spinal deformity characterized by lateral curvature and axial rotation around the vertical body axis of the spine, the cause of which is yet unknown. The fast progression entails regular clinical monitoring, including X-rays. Here we present an approach to evaluate scoliosis from the three-dimensional image of a patient’s torso, captured by an ionizing radiation free body scanner, in combination with a model of the ribcage and spine. A skeletal structure of the ribcage and vertebral column was modelled with computer aided designed software and was used as an initial structure for macroscopic finite element method simulations. The basic vertebral column model was created for an adult female in an upright position. The model was then used to simulate the patient specific scoliotic spine configurations. The simulations showed that a lateral translation of a vertebral body results in an effective axial rotation and could reproduce the spinal curvatures. The combined method of three-dimensional body scan and finite element model simulations thus provide quantitative anatomical information about the position, rotation and inclination of the thoracic and lumbar vertebrae within a three-dimensional torso. Furthermore, the simulations showed unequal distributions of stress and strain profiles across the intervertebral discs, due to their distortions, which might help to further understand the pathogenesis of scoliosis.
50
Suchomel, Petr, Pavel Buchvald, Pavel Barsa, Robert Froehlich, Ondrej Choutka, Zdenek Krejzar, Petra Sourkova, Ladislav Endrych, and Ladislav Dzan. "Single-stage total C-2 intralesional spondylectomy for chordoma with three-column reconstruction." Journal of Neurosurgery: Spine 6, no. 6 (June 2007): 611–18. http://dx.doi.org/10.3171/spi.2007.6.6.17.
Анотація:
✓Chordomas are locally invasive, malignant bone tumors that rarely occur in the cervical spine. En bloc resection or even fully resecting the tumor along its margin offers improved patient survival and a potential disease cure. Complete resection of tumors involving the upper cervical vertebrae requires a combined anterior–posterior approach but is complicated by the presence of vertebral arteries (VAs). In addition, reconstruction of the postresection defect may be prone to failure. The authors present a case of a chordoma involving the axis that was treated using a single-stage total intralesional C-2 spondylectomy with preservation of both VAs because the patient did not tolerate a preoperative occlusion test. A three-column reconstruction technique is also presented.