Analysis of the uncinate processes of the cervical spine: an anatomical study

2012 ◽  
Vol 16 (4) ◽  
pp. 402-407 ◽  
Author(s):  
R. Shane Tubbs ◽  
Olivia J. Rompala ◽  
Ketan Verma ◽  
Martin M. Mortazavi ◽  
Brion Benninger ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Anatomical Study ◽  
Axial Rotation ◽  
Intervertebral Discs ◽  
Uncinate Process ◽  
Surgical Approaches ◽  
Intervertebral Foramen ◽  
Facet Joints ◽  
Vertebral Level ◽  
Arthritic Changes

Object Although the uncovertebral region is neurosurgically relevant, relatively little is reported in the literature, specifically the neurosurgical literature, regarding its anatomy. Therefore, the present study aimed at further elucidation of this region's morphological features. Methods Morphometry was performed on the uncinate processes of 40 adult human skeletons. Additionally, range of motion testing was performed, with special attention given to the uncinate processes. Finally, these excrescences were classified based on their encroachment on the adjacent intervertebral foramen. Results The height of these processes was on average 4.8 mm, and there was an inverse relationship between height of the uncinate process and the size of the intervertebral foramen. Degeneration of the vertebral body (VB) did not correlate with whether the uncinate process effaced the intervertebral foramen. The taller uncinate processes tended to be located below C-3 vertebral levels, and their average anteroposterior length was 8 mm. The average thickness was found to be 4.9 mm for the base and 1.8 mm for the apex. There were no significant differences found between vertebral level and thickness of the uncinate process. Arthritic changes of the cervical VBs did not necessarily deform the uncinate processes. With axial rotation, the intervertebral discs were noted to be driven into the ipsilateral uncinate process. With lateral flexion, the ipsilateral uncinate processes aided the ipsilateral facet joints in maintaining the integrity of the ipsilateral intervertebral foramen. Conclusions A good appreciation for the anatomy of the uncinate processes is important to the neurosurgeon who operates on the spine. It is hoped that the data presented herein will decrease complications during surgical approaches to the cervical spine.

scholarly journals Development of differentiated surgical technique for treating patients with multilevel degenerative diseases of cervical spine

2019 ◽  
pp. 47-54
Author(s):  
V. A. Byvaltsev ◽  
A. A. Kalinin ◽  
M. A. Aliyev ◽  
V. V. Shepelev ◽  
B. R. Yusupov ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Disease Duration ◽  
Intervertebral Discs ◽  
Adverse Outcomes ◽  
Neurological Symptoms ◽  
Cervical Region ◽  
Degenerative Diseases ◽  
Facet Joints ◽  
On Line ◽  
Surgical Tactics

Background. Currently, there is no uniform tactics for the differentiated use of dorsal decompressive-stabilizing techniques for multilevel degenerative diseases of the cervical spine, and the results of these technologies application are largely controversial.Aim. Analysis of the unsatisfactory outcomes of dorsal decompressive-stabilizing interventions in the treatment of patients with multilevel degenerative diseases of the cervical spine and development of a clinicalinstrumental algorithm for differentiated surgical tactics.Material and methods. A retrospective study included 112 patients with degenerative diseases of the cervical spine at two levels or more due to hernias of intervertebral discs, yellow ligament hypertrophy and arthrosis of facet joints, which in 2007-2014 underwent dorsal decompressive-stabilizing interventions in the volume of laminotomy with laminoplasty (LP) and laminectomy with fixation for lateral masses (LF). A correlation analysis of clinical parameters with anamnestic data, instrumental parameters, a feature of accepted surgical tactics and postoperative adverse effects.Results. In the analysis, it was established that «satisfactory» postoperative outcomes of LP are associated with a neutral or lordotic configuration of the cervical spine, the preservation of segmental movements without clinical and instrumental signs of instability; In addition, the use of LF is possible with mobile kyphotization of the cervical spine and the presence of translational instability of the cervical segments. The «unsatisfactory» postoperative results of the LP and LF are in direct correlation with the duration of the disease, the presence of myelopathic focus and rigid kyphosis of the cervical region.Conclusion. Differential use of dorsal decompressive-stabilizing techniques based on a comprehensive assessment of disease duration, configuration of the cervical spine, spinal cord condition and volume of segmental movements allows to reduce neurological symptoms, improve the level of pain and improve the functional status of patients, as well as significantly reduce the number of adverse outcomes associated with the progression of kyphotic deformity, deterioration of neurological symptoms and revision on-line decompressive-stabilizing interventions. 

A BIOMECHANICAL STUDY OF THE EFFECTS OF FLEXION ANGLE ON THE INDUCTION MECHANISM OF CERVICAL SPONDYLOSIS

2021 ◽  
pp. 2150053
Author(s):  
FU CAO ◽  
RONGCHANG FU ◽  
WENYUAN WANG
Keyword(s):  
Cervical Spine ◽  
Cervical Spondylosis ◽  
Element Model ◽  
Intervertebral Discs ◽  
Biomechanical Study ◽  
Flexion Angle ◽  
Facet Joints ◽  
Load Increase ◽  
Spine Motion ◽  
Wolff’S Law

Lesions in facet joints such as bone hyperplasia and degenerative changes in the intervertebral discs, can compress nerve roots and the spinal cord, leading to cervical spondylosis (CS). Lesions in these parts of the spine are commonly related to abnormal loads caused by bad posture of the cervical spine. This study aimed to understand the potential mechanical effects of load amplitude on cervical spine motion to provide a theoretical basis for the biomechanical causes of CS, and to provide a reference for preventing of the condition. In this study, a finite element model of the normal human cervical spine (C1-C7) was established and validated using an infrared motion capture system to analyze the effects of flexion angle on the stresses experienced by intervertebral discs, the anterior edge of the vertebral body, the pedicle, uncinate and facet joints. Our analysis indicated that the intervertebral disc load increased by at least 70% during the 20∘ to 45∘ flexion of the neck with 121% load increase in the vertebrae. In the intervertebral discs, the stress was largest at C4-C5, and the stress was moderate at C5-C6. These results are consistent with clinical CS prone site research. According to Wolff’s law, when bones are placed under large stresses, hyperplasia can result to allow adaptation to large loads. Increased cervical spine flexion angles caused the proliferation of bone in the above-mentioned parts of the spine and can accelerate accelerating the appearance of CS.

Numerical investigation on the stability of human upper cervical spine (C1–C3)

2021 ◽  
pp. 1-13
Author(s):  
Waseem Ur Rahman ◽  
Wei Jiang ◽  
Guohua Wang ◽  
Zhijun Li
Keyword(s):  
Finite Element ◽  
Cervical Spine ◽  
Axial Rotation ◽  
Upper Cervical Spine ◽  
Fe Model ◽  
Facet Joints ◽  
Flexion Extension ◽  
Upper Cervical ◽  
The Stability

BACKGROUND: The finite element method (FEM) is an efficient and powerful tool for studying human spine biomechanics. OBJECTIVE: In this study, a detailed asymmetric three-dimensional (3D) finite element (FE) model of the upper cervical spine was developed from the computed tomography (CT) scan data to analyze the effect of ligaments and facet joints on the stability of the upper cervical spine. METHODS: A 3D FE model was validated against data obtained from previously published works, which were performed in vitro and FE analysis of vertebrae under three types of loads, i.e. flexion/extension, axial rotation, and lateral bending. RESULTS: The results show that the range of motion of segment C1–C2 is more flexible than that of segment C2–C3. Moreover, the results from the FE model were used to compute stresses on the ligaments and facet joints of the upper cervical spine during physiological moments. CONCLUSION: The anterior longitudinal ligaments (ALL) and interspinous ligaments (ISL) are found to be the most active ligaments, and the maximum stress distribution is appear on the vertebra C3 superior facet surface under both extension and flexion moments.

Quantifying the ranges of relative motions of the intervertebral discs and facet joints in the normal cervical spine

2020 ◽  
Vol 112 ◽  
pp. 110023 ◽  
Author(s):  
Haiming Wang ◽  
Chaochao Zhou ◽  
Yan Yu ◽  
Cong Wang ◽  
Tsung-Yuan Tsai ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Intervertebral Discs ◽  
Facet Joints ◽  
Relative Motions

scholarly journals A Review on Diagnosis and Management of Cervical Spondylosis

2021 ◽  
pp. 668-674
Author(s):  
Ahmed Abdulaziz G. Ibrahim ◽  
Ali Mohammed A. Alahmari ◽  
Abdullah Hassan F. Alsuayri ◽  
Abdullah Misfer M. Algomshah ◽  
Saeed Ghanem S. Almlfi ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Neck Pain ◽  
Cervical Spondylosis ◽  
Natural Aging ◽  
Posterior Longitudinal Ligament ◽  
Cervical Radiculopathy ◽  
Intervertebral Discs ◽  
Degenerative Changes ◽  
Facet Joints ◽  
Wide Range

Cervical spondylosis is a term that encompasses a wide range of progressive degenerative changes that affect all components of the cervical spine (i.e., intervertebral discs, facet joints, Luschka joints, flava ligaments, and laminae). It is a natural aging process and occurs in most people after the age of five. Most people with radiographic spondylotic changes in the cervical spine  remain asymptomatic, and 25% of those under  40, 50% of those over  40, and 85% of those over  60 show some evidence of degenerative changes , including changes in  the environment. Uncovertebral joints, facet joints, posterior longitudinal ligament (PLL) and yellow ligament lead to  narrowing of the spinal canal and intervertebral foramina. As a result, the spinal cord, spinal vasculature, and nerve roots can become compressed, leading to the three clinical syndromes that occur with cervical spondylosis: axial neck pain, cervical myelopathy, and cervical radiculopathy. Cervical spondylosis is usually diagnosed for clinical reasons only, but imaging is also required. Treatment for cervical spondylosis can be medical or surgical, depending on whether the patient has symptoms of myelopathy, radicular pain, or neck pain.

The effect of spinal instrumentation on kinematics at the cervicothoracic junction: emphasis on soft-tissue response in an in vitro human cadaveric model

2010 ◽  
Vol 13 (4) ◽  
pp. 435-442 ◽  
Author(s):  
Ryan M. Kretzer ◽  
Nianbin Hu ◽  
Hidemasa Umekoji ◽  
Daniel M. Sciubba ◽  
George I. Jallo ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Pedicle Screw ◽  
Axial Rotation ◽  
Cervical Region ◽  
Facet Joints ◽  
Lateral Bending ◽  
Cervicothoracic Junction ◽  
Thoracic Pedicle Screw ◽  
Flexion Extension ◽  
Intact Condition

Object Thoracic pedicle screw instrumentation is often indicated in the treatment of trauma, deformity, degenerative disease, and oncological processes. Although classic teaching for cervical spine constructs is to bridge the cervicothoracic junction (CTJ) when instrumenting in the lower cervical region, the indications for extending thoracic constructs into the cervical spine remain unclear. The goal of this study was to determine the role of ligamentous and facet capsule (FC) structures at the CTJ as they relate to stability above thoracic pedicle screw constructs. Methods A 6-degree-of-freedom spine simulator was used to test multidirectional range of motion (ROM) in 8 human cadaveric specimens at the C7–T1 segment. Flexion-extension, lateral bending, and axial rotation at the CTJ were tested in the intact condition, followed by T1–6 pedicle screw fixation to create a long lever arm inferior to the C7–T1 level. Multidirectional flexibility testing of the T1–6 pedicle screw construct was then sequentially performed after sectioning the C7–T1 supraspinous ligament/interspinous ligament (SSL/ISL) complex, followed by unilateral and bilateral FC disruption at C7–T1. Finally, each specimen was reconstructed using C5–T6 instrumented fixation and ROM testing at the CTJ performed as previously described. Results Whereas the application of a long-segment thoracic construct stopping at T-1 did not significantly increase flexion-extension peak total ROM at the supra-adjacent level, sectioning the SSL/ISL significantly increased flexibility at C7–T1, producing 35% more motion than in the intact condition (p < 0.05). Subsequent FC sectioning had little additional effect on ROM in flexion-extension. Surprisingly, the application of thoracic instrumentation had a stabilizing effect on the supra-adjacent C7–T1 segment in axial rotation, leading to a decrease in peak total ROM to 83% of the intact condition (p < 0.05). This is presumably due to interaction between the T-1 screw heads and titanium rods with the C7–T1 facet joints, thereby limiting axial rotation. Incremental destabilization served only to restore peak total ROM near the intact condition for this loading mode. In lateral bending, the application of thoracic instrumentation stopping at T-1, as well as SSL/ISL and FC disruption, demonstrated trends toward increased supraadjacent ROM; however, these trends did not reach statistical significance (p > 0.05). Conclusions When stopping thoracic constructs at T-1, care should be taken to preserve the SSL/ISL complex to avoid destabilization of the supra-adjacent CTJ, which may manifest clinically as proximal-junction kyphosis. In an analogous fashion, if a T-1 laminectomy is required for neural decompression or surgical access, consideration should be given to extending instrumentation into the cervical spine. Facet capsule disruption, as might be encountered during T-1 pedicle screw placement, may not be an acutely destabilizing event, due to the interaction of the C7–T1 facet joints with T-1 instrumentation.

Characterization of Irregular Stress Distributions Induced by Klippel Feil Syndrome

2011 ◽  
Author(s):  
Enoch Leung ◽  
Nesrin Sarigul-Klijn ◽  
Rolando F. Roberto
Keyword(s):  
Cervical Spine ◽  
Structural Integrity ◽  
Cervical Vertebrae ◽  
Axial Rotation ◽  
Intervertebral Discs ◽  
Stress Distributions ◽  
Modeling And Analysis ◽  
Vertebral Fusion ◽  
Flexion Extension ◽  
Spine Segment

Klippel Feil Syndrome (KFS) is a congenital disorder characterized by failure of segmentation of cervical vertebrae, resulting in “fusions” at any level of the cervical spine. Clinical diagnosis of KFS occurs at a mean age of 7.1 years, with children diagnosed with KFS often exhibiting reduced motion and function characterized by reduction of upward and downward motions of the head on the neck (flexion/extension), axial rotation, and tilting of the head side to side (lateral bending). More importantly, however, previous KFS studies have acknowledged possible compromises to the structural integrity and overall health of the cervical spine in the presence of abnormal fusion. Instances of instabilities such as fracture and large amounts of mobility at vertebral segments adjacent to fusion have been recorded, both posing significant neurological and physiological dangers to an individual afflicted with KFS. While fusion and instability appear to be interrelated, more intrinsic evaluation of KFS-related instabilities is needed. Current KFS studies, relying predominantly on static radiographic modalities, have been unsuccessful in identifying factors contributing to craniocervical (CC) destabilization in the presence of congenital vertebral fusion. It has been hypothesized that fusion of vertebral bodies induces abnormal stress distributions that catalyze instances of fracture along any KFS spine segment. Using Finite Element (FE) Modeling and Analysis to characterize motion alterations and irregular stress patterns associated with vertebral fusion, a high fidelity computational representation of a KFS affected cervical spine segment spanning the base of the occiput to C6 was constructed. Computer Tomography (CT) images were used for vertebral reconstruction with soft tissue components such as intervertebral discs (IVDs), articular cartilages (ACs), and the transverse ligament were modeled as homogenous solid components.

scholarly journals Tomodensitometric Bone Anatomy of The Intervertebral Foramen of The Lower Cervical Spine: Measurements and Comparison of Foraminal Volume in Healthy Individuals and Patients Suffering from Cervicobrachial Neuralgia Due to Foraminal Stenosis.

2022 ◽  
Author(s):  
Pierre COUDERT ◽  
Gaetan LAINE ◽  
Vincent POINTILLART ◽  
Camille DAMADE ◽  
Louis BOISSIERE ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Current Knowledge ◽  
Intervertebral Discs ◽  
Lateral Part ◽  
Foraminal Stenosis ◽  
Medial Part ◽  
Lower Cervical Spine ◽  
Intervertebral Foramen ◽  
Asymptomatic Group ◽  
Symptomatic Group

Abstract Purpose Degenerative foraminal stenosis of the cervical spine can lead to cervicobrachial neuralgias. Computed tomography (CT)-scan assists in the diagnosis and evaluation of foraminal stenosis. The main objective of this study is to determine the bony dimensions of the cervical intervertebral foramen and to identify which foraminal measurements are most affected by degenerative disorders of the cervical spine. These data could be applied to the surgical treatment of this pathology, helping surgeons to focus on specific areas during decompression procedures. Methods A descriptive study was conducted between two groups: an asymptomatic one (young people with no evidence of degenerative cervical spine disorders) and a symptomatic one (experiencing cervicobrachial neuralgia due to degenerative foraminal stenosis). Using CT scans, we determined a method allowing measurements of the following foraminal dimensions: foraminal height (FH), foraminal length (FL), foraminal width in its lateral part ((UWPP, MWPP and IWPP (respectively Upper, Medial and Inferior Width of Pedicle Part)) and medial part (UWMP, MWMP and IWMP (respectively Upper, Medial and Inferior Width of Medial Part)), and disk height (DH). Foraminal volume (FV) was calculated considering the above data. Mean volumes were measured in the asymptomatic group and compared to the values obtained in the symptomatic group. Results Both groups were made up of 10 patients, and a total of 50 intervertebral discs (100 intervertebral foramina) were analyzed in each group. Comparison of C4C5, C5C6 and C6C7 levels between both groups showed several significant decreases in foraminal dimensions (p< 0,05) as well as in foraminal volume (p <0.001) in the symptomatic group. The most affected dimensions were UWPP, MWPP, UWMP, MWMP and FV. The most stenotic foraminal areas were the top of the uncus and the posterior edge of the lower plate of the overlying vertebra. Conclusion Using a new protocol for measuring foraminal volume, the present study refines the current knowledge of the normal and pathological anatomy of the lower cervical spine and allows us to understand the foraminal sites most affected by degenerative stenosis. Those findings can be applied to foraminal stenosis surgeries. According to our results, decompression of the foramen in regard of both uncus osteophytic spurs and inferior plate of the overlying vertebra might be an important step for nerve roots release.

Stress Changes in Intervertebral Discs of the Cervical Spine After Partial Fusion

2003 ◽  
Author(s):  
Abraham Tchako ◽  
Ali M. Sadegh
Keyword(s):  
Cervical Spine ◽  
Axial Rotation ◽  
Intervertebral Discs ◽  
Fe Model ◽  
Loading Mode ◽  
Flexion Extension ◽  
Stress Changes ◽  
Partial Fusion ◽  
The Difference ◽  
Disc Level

A detailed and validated 3D FE model of human cervical spine (Sadegh et al. 2000) was altered to simulate partial fusion. Five single level partially fused new models, one at each disc level, were used to study the change in stresses in adjacent levels. Two cases of partial fusion, 80% and 60% were considered. The fused models were loaded with a 50 N compressive pre-load and with a 1.5 Nm moment in flexion, extension, lateral bending and axial rotation. The previously obtained results of the unfused model (Tchako et al. 2002) and of the fused models were used to study the change in stresses in adjacent levels. The results indicate that, in general, there are stress changes as high as 94%, depending on the loading mode and location, in adjacent discs after discectomy and fusion. However, the difference between the stress change of 80% and 60% of partial fusion is insignificant.

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