scholarly journals Effects of occipital-atlas stabilization in the upper cervical spine kinematics: an in vitro study

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
César Hidalgo-García ◽  
Ana I. Lorente ◽  
Carlos López-de-Celis ◽  
Orosia Lucha-López ◽  
Miguel Malo-Urriés ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Sagittal Plane ◽  
Frontal Plane ◽  
In Vitro Study ◽  
Upper Cervical Spine ◽  
Lateral Flexion ◽  
Alar Ligament ◽  
Before And After ◽  
Upper Cervical

AbstractThis study compares upper cervical spine range of motion (ROM) in the three cardinal planes before and after occiput-atlas (C0–C1) stabilization. After the dissection of the superficial structures to the alar ligament and the fixation of C2, ten cryopreserved upper cervical columns were manually mobilized in the three cardinal planes of movement without and with a screw stabilization of C0–C1. Upper cervical ROM and mobilization force were measured using the Vicon motion capture system and a load cell respectively. The ROM without C0–C1 stabilization was 19.8° ± 5.2° in flexion and 14.3° ± 7.7° in extension. With stabilization, the ROM was 11.5° ± 4.3° and 6.6° ± 3.5°, respectively. The ROM without C0–C1 stabilization was 4.7° ± 2.3° in right lateral flexion and 5.6° ± 3.2° in left lateral flexion. With stabilization, the ROM was 2.3° ± 1.4° and 2.3° ± 1.2°, respectively. The ROM without C0–C1 stabilization was 33.9° ± 6.7° in right rotation and 28.0° ± 6.9° in left rotation. With stabilization, the ROM was 28.5° ± 7.0° and 23.7° ± 8.5° respectively. Stabilization of C0–C1 reduced the upper cervical ROM by 46.9% in the sagittal plane, 55.3% in the frontal plane, and 15.6% in the transverse plane. Also, the resistance to movement during upper cervical mobilization increased following C0–C1 stabilization.

scholarly journals In Vitro Upper Cervical Spine Kinematics: Rotation with Combined Movements and its Variation After Alar Ligament Transection

2021 ◽  
pp. 110872
Author(s):  
Ana I. LORENTE ◽  
César HIDALGO-GARCÍA ◽  
Pablo FANLO-MAZAS ◽  
Jacobo RODRÍGUEZ-SANZ ◽  
Carlos LÓPEZ-de-CELIS ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Upper Cervical Spine ◽  
Alar Ligament ◽  
Spine Kinematics ◽  
Upper Cervical ◽  
Combined Movements

Circular Tomosynthesis: Potential in Imaging of Breast and Upper Cervical Spine—Preliminary Phantom and in Vitro Study

Radiology ◽  
2003 ◽  
Vol 228 (2) ◽  
pp. 569-575 ◽  
Author(s):  
Grant M. Stevens ◽  
Robyn L. Birdwell ◽  
Christopher F. Beaulieu ◽  
Debra M. Ikeda ◽  
Norbert J. Pelc
Keyword(s):  
Cervical Spine ◽  
In Vitro Study ◽  
Vitro Study ◽  
Upper Cervical Spine ◽  
Upper Cervical

In vitro 3D-kinematics of the upper cervical spine: helical axis and simulation for axial rotation and flexion extension

2009 ◽  
Vol 32 (2) ◽  
pp. 141-151 ◽  
Author(s):  
Pierre-Michel Dugailly ◽  
Stéphane Sobczak ◽  
Victor Sholukha ◽  
Serge Van Sint Jan ◽  
Patrick Salvia ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Axial Rotation ◽  
Helical Axis ◽  
Upper Cervical Spine ◽  
3D Kinematics ◽  
Flexion Extension ◽  
Upper Cervical

scholarly journals Upper Cervical Spine Stability: Maximum Rotation and the Rotation Stress Test in Clinics

2019 ◽  
Vol 7 ◽  
Author(s):  
Ana I Lorente ◽  
Mario Maza Frechín ◽  
Albert Pérez Bellmunt ◽  
César Hidalgo García
Keyword(s):  
Cervical Spine ◽  
Stress Test ◽  
Craniocervical Junction ◽  
Upper Cervical Spine ◽  
Spine Stability ◽  
Upper Cervical ◽  
Rotation Stress

The rotation stress test is used to evaluate stability of the craniocervical junction by assuming that it gives the maximum rotation. However, a more complex manipulation might show a higher rotation: the rotation with extension and contralateral bending. This was tested in vitro with ten upper cervical spine specimens.

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.

The Mechanics of Cervical Muscle Recruitment on Cervical Spine Stability —A Biomechanical in Vitro Study using Porcine Model

2008 ◽  
Vol 24 (1) ◽  
pp. 63-68 ◽  
Author(s):  
C.-H. Cheng ◽  
T.-Y. Chen ◽  
Y.-W. Kuo ◽  
J.-L. Wang
Keyword(s):  
Cervical Spine ◽  
Muscle Force ◽  
Sagittal Plane ◽  
In Vitro Study ◽  
Spinal Stability ◽  
Muscle Recruitment ◽  
Spine Stability ◽  
Cervical Muscles ◽  
The Stability

ABSTRACTCervical muscles are crucial in providing the stability of the cervical spine. Many in vitro studies have investigated the relationship between muscle force and stability directly. However, the effects of different muscle dysfunctions or muscle recruitments on cervical spine stability are not yet clear and therefore, worthy of study. A spine testing apparatus with muscle force replication activated by pneumatic cylinders was developed to find the effect of muscles on spinal stability. Seven porcine cervical spines (C2-T1) were used. Three pairs of cervical muscles, including neck flexors (sternocleidomastoid, SCM) and neck extensors (splenius capitis, SPL; semispinalis capitis, SSC), were simulated. The experimental tests included: 1. no muscle recruitment, 2. full muscle recruitments, 3. SCM dysfunction, 4. SPL dysfunction, and 5. SSC dysfunction. The external pure moment in sagittal plane was applied from 0 Nm to 2 Nm to examine the stability/flexibility of specimens. The spinal stability was evaluated by the neutral zone (NZ), the range of motion (ROM), the reduced NZ (R_NZ), and the reduced ROM (R_ROM). Loading responses of C7-T1 disc were also measured. The results of this study showed: The activation of cervical muscles decreased the NZ and ROM. The degree of decrease among different muscle dysfunctions, however, was not significantly different. The SPL dysfunction induced larger anterior shear force, while the SCM dysfunction exclusively induced extension moment. In conclusion, the muscle forces could stabilize the cervical spine, but significant decrease in spinal stability was not found among dysfunctions of different muscles. The SCM and SPL dysfunction may result in abnormal stress at the C7-T1 disc.

In vitro investigations of internal fixation systems of the upper cervical spine

1992 ◽  
Vol 1 (3) ◽  
pp. 185-190 ◽  
Author(s):  
H. -J. Wilke ◽  
K. Fischer ◽  
A. Kugler ◽  
F. Magerl ◽  
L. Claes ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Internal Fixation ◽  
Upper Cervical Spine ◽  
Upper Cervical

scholarly journals Study of the Distortion of the Indirect Angular Measurements of the Calcaneus Due to Perspective: In Vitro Testing

Sensors ◽  
2021 ◽  
Vol 21 (8) ◽  
pp. 2585
Author(s):  
Isidoro Espinosa-Moyano ◽  
María Reina-Bueno ◽  
Inmaculada C. Palomo-Toucedo ◽  
José Rafael González-López ◽  
José Manuel Castillo-López ◽  
...  
Keyword(s):  
Sagittal Plane ◽  
Frontal Plane ◽  
In Vitro Study ◽  
Body Segment ◽  
The Real ◽  
Foot Progression Angle ◽  
Regression Formula ◽  
Angular Measurements ◽  
Kinematic Analyses

The study of the foot is relevant in kinematic analyses of gait. Images captured through a lens can be subjected to various aberrations or distortions that affect the measurements. An in vitro study was performed with a rearfoot simulator to compare the apparent degrees (photographed) with the real ones (placed in the simulator) in the plane of the rearfoot’s orientation, according to variations in the capture angle in other planes of space (the sagittal plane and transverse plane—the latter determined by the foot progression angle). The following regression formula was calculated to correct the distortion of the image: real frontal plane = 0.045 + (1.014 × apparent frontal plane) − (0.018 × sagittal plane × foot progression angle). Considering the results of this study, and already knowing its angle in the transverse and sagittal planes, it is possible to determine the angle of a simulated calcaneus with respect to the ground in the frontal plane, in spite of distortions caused by perspective and the lack of perpendicularity, by applying the above regression formula. The results show that the angular measurements of a body segment made on frames can produce erroneous data due to the variation in the perspective from which the image is taken. This distortion must be considered when determining the real values of the measurements.

Tension and Combined Tension-Extension Structural Response and Tolerance Properties of the Human Male Ligamentous Cervical Spine

2009 ◽  
Vol 131 (8) ◽  
Author(s):  
Alan T. Dibb ◽  
Roger W. Nightingale ◽  
Jason F. Luck ◽  
V. Carol Chancey ◽  
Lucy E. Fronheiser ◽  
...  
Keyword(s):  
Cervical Spine ◽  
Sagittal Plane ◽  
Model Development ◽  
Structural Response ◽  
Tensile Load ◽  
Beam Theory ◽  
Head Rotation ◽  
Tensile Loading ◽  
Upper Cervical Spine ◽  
Upper Cervical

Tensile loading of the human cervical spine results from noncontact inertial loading of the head as well as mandibular and craniofacial impacts. Current vehicle safety standards include a neck injury criterion based on beam theory that uses a linear combination of the normalized upper cervical axial force and sagittal plane moment. This study examines this criterion by imposing combined axial tension and bending to postmortem human subject (PMHS) ligamentous cervical spines. Tests were conducted on 20 unembalmed PMHSs. Nondestructive whole cervical spine tensile tests with varying cranial end condition and anteroposterior loading location were used to generate response corridors for computational model development and validation. The cervical spines were sectioned into three functional spinal segments (Occiput-C2, C4-C5, and C6-C7) for measurement of tensile structural response and failure testing. The upper cervical spine (Occiput-C2) was found to be significantly less stiff, absorb less strain energy, and fail at higher loads than the lower cervical spine (C4-C5 and C6-C7). Increasing the moment arm of the applied tensile load resulted in larger head rotations, larger moments, and significantly higher tensile ultimate strengths in the upper cervical spine. The strength of the upper cervical spine when loaded through the head center of gravity (2417±215 N) was greater than when loaded over the occipital condyles (2032±250 N), which is not predicted by beam theory. Beam theory predicts that increased tensile loading eccentricity results in decreased axial failure loads. Analyses of the force-deflection histories suggest that ligament loading in the upper cervical spine depends on the amount of head rotation orientation, which may explain why the neck is stronger in combined tension and extension.

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