Spinal Cord Parenchyma Vascular Redistribution Underlies Hemodynamic and Neurophysiological Changes at Dynamic Neck Positions in Cervical Spondylotic Myelopathy

Cervical spondylotic myelopathy (CSM) is a degenerative condition of the spine that caused by static and dynamic compression of the spinal cord. However, the mechanisms of motor and somatosensory conduction, as well as pathophysiological changes at dynamic neck positions remain unclear. This study aims to investigate the interplay between neurophysiological and hemodynamic responses at dynamic neck positions in the CSM condition, and the pathological basis behind. We first demonstrated that CSM patients had more severe dynamic motor evoked potentials (DMEPs) deteriorations upon neck flexion than upon extension, while their dynamic somatosensory evoked potentials (DSSEPs) deteriorated to a similar degree upon extension and flexion. We therefore generated a CSM rat model which developed similar neurophysiological characteristics within a 4-week compression period. At 4 weeks-post-injury, these rats presented decreased spinal cord blood flow (SCBF) and oxygen saturation (SO2) at the compression site, especially upon cervical flexion. The dynamic change of DMEPs was significantly correlated with the change in SCBF from neutral to flexion, suggesting they were more sensitive to ischemia compared to DSSEPs. We further demonstrated significant vascular redistribution in the spinal cord parenchyma, caused by angiogenesis mainly concentrated in the anterior part of the compressed site. In addition, the comparative ratio of vascular densities at the anterior and posterior parts of the cord was significantly correlated with the perfusion decrease at neck flexion. This exploratory study revealed that the motor and somatosensory conductive functions of the cervical cord changed differently at dynamic neck positions in CSM conditions. Compared with somatosensory conduction, the motor conductive function of the cervical cord suffered more severe deteriorations upon cervical flexion, which could partly be attributed to its higher susceptibility to spinal cord ischemia. The uneven angiogenesis and vascular distribution in the spinal cord parenchyma might underlie the transient ischemia of the cord at flexion.

Weakness With Neck Flexion

A 51-year-old woman sought care for difficulty “picking up” her right foot after walking for 30 minutes; with rest, the symptoms would subside. A few months later, she reported a “zinging” sensation in her right 4th and 5th fingers and down her right side with neck flexion. Brain magnetic resonance imaging showed tiny nonspecific lesions not suggestive of demyelinating disease and a single T2 hyperintensity at the cervicomedullary junction that did not enhance with gadolinium administration. Cerebrospinal fluid analysis showed 10 oligoclonal bands on isoelectric focusing electrophoresis and a mildly increased immunoglobulin G index of 0.73. The patient was diagnosed with solitary sclerosis, suspected to be a form of central nervous system demyelinating disease strongly related to multiple sclerosis. Treatment was based on a diagnosis of “primary progressive multiple sclerosis,” although the patient did not satisfy the criterion of dissemination in space. The patient was being treated with glatiramer acetate 40 mg 3 times weekly for a presumptive diagnosis of multiple sclerosis before evaluation at Mayo Clinic. After our evaluation, she was advised that no treatments at that time were efficacious to prevent deterioration in patients with primary progressive multiple sclerosis. The mainstay of treatment is physical medicine modalities, including principles of energy conservation and, when necessary, mobility aids, such as braces and canes. The presentation of disease in this patient suggested a chronic myelopathy. Her symptoms did not develop acutely and manifested only after she walked a distance. Symptoms involving the upper and lower extremities and precipitation of Lhermitte sign with neck flexion also suggested a spinal cord lesion, typically a demyelinating lesion. However, a single spinal cord lesion present at the cervicomedullary junction. Oligoclonal bands are detected in patients with central nervous system infections or paraneoplastic disorders that might be associated with myelopathy.

Evaluation of a Computer Vision-Based System to Analyse Behavioral Changes in High School Classrooms

The objectives of this study were to investigate the feasibility of applying computer vision techniques and to analyse changes in behaviour and movement of high school students during class. The study is performed over two phases. Phase one focuses on developing a feasible method to use computer vision-based techniques in high school classes and phase two focuses on the testing of aromatherapy to affect student’s movement. All camera data was processed and analysed by OpenPose, Matlab and EyesWeb. Movement features such as velocity, acceleration, and kinetic energy and postural variables, spinal extension and neck flexion were calculated. Results of phase one, shows significant differences in the overall segment velocity, acceleration, energy, and neck flexion. Similarly, the second phase shows significant differences in velocity, acceleration and jerk for the left shoulder and elbow joints of the group exposed to aroma. In conclusion, the results show the feasibility of using computer vision techniques to apply in a classroom setting.

EVALUATION OF A COMPUTER VISION-BASED SYSTEM TO ANALYSE BEHAVIORAL CHANGES IN HIGH SCHOOL CLASSROOMS

The objectives of this study were to investigate the feasibility of applying computer vision techniques and to analyse changes in behaviour and movement of high school students during class. The study is performed over two phases. Phase one focuses on developing a feasible method to use computer vision-based techniques in high school classes and phase two focuses on the testing of aromatherapy to affect student’s movement. All camera data was processed and analysed by OpenPose, Matlab and EyesWeb. Movement features such as velocity, acceleration, and kinetic energy and postural variables, spinal extension and neck flexion were calculated. Results of phase one, shows significant differences in the overall segment velocity, acceleration, energy, and neck flexion. Similarly, the second phase shows significant differences in velocity, acceleration and jerk for the left shoulder and elbow joints of the group exposed to aroma. In conclusion, the results show the feasibility of using computer vision techniques to apply in a classroom setting.

Atypical Pupil Reactions in Brain Dead Patients

Background: During routine diagnosis of brain death, changes in pupil diameter in response to the stimulation of peripheral nerves are sometimes observed. For example, pupillary dilation after diagnosed brain death is described in the literature as the ciliospinal reflex. However, pupil constriction creates diagnostic doubts. Objective: The pupillometric analysis of pupil response to stimulation of the cervicothoracic spinal cord in patients with diagnosed brain death. Methods: Instrumental tests to confirm the arrest of cerebral circulation were performed in 30 adult subjects (mean age 53.5 years, range 26–75 years) with diagnosed brain death. In addition, a pupillometer was used to measure the change in pupil diameter in response to neck flexion. Intervention: Flexion of the neck and measuring the response in change of the pupil with the use of the pupillometer. Results: The change in the pupil was observed in the examined group of patients. Difference in pupil size ≥ 0.2 mm was observed in 14 cases (46%). In five cases (17%), pupil constriction was found (from 0.2 to 0.7 mm). Measurement error was +/− 0.1 mm. Conclusions: Both pupillary constriction and dilatation may occur due to a ciliospinal reflex in patients with brain death. This phenomenon needs further research in order to establish its pathophysiology.

Differentiating migraine, cervicogenic headache and asymptomatic individuals based on physical examination findings: a systematic review and meta-analysis

Background Migraine and cervicogenic headache (CGH) are common headache disorders, although the large overlap of symptoms between them makes differential diagnosis challenging. To strengthen differential diagnosis, physical testing has been used to examine for the presence of musculoskeletal impairments in both conditions. This review aimed to systematically evaluate differences in physical examination findings between people with migraine, CGH and asymptomatic individuals. Methods The databases MEDLINE, PubMed, CINAHL, Web of Science, Scopus, EMBASE were searched from inception until January 2020. Risk of bias was assessed with the Downs and Black Scale for non-randomized controlled trials, and with the Quality Assessment of Diagnostic Accuracy Studies tool for diagnostic accuracy studies. When possible, meta-analyses with random effect models was performed. Results From 19,682 articles, 62 studies were included in this review and 41 were included in the meta-analyses. The results revealed: a) decreased range of motion [°] (ROM) on the flexion-rotation test (FRT) (17.67, 95%CI:13.69,21.65) and reduced neck flexion strength [N] (23.81, 95%CI:8.78,38.85) in CGH compared to migraine; b) compared to controls, migraineurs exhibit reduced flexion ROM [°] (− 2.85, 95%CI:-5.12,-0.58), lateral flexion ROM [°] (− 2.17, 95% CI:-3.75,-0.59) and FRT [°] (− 8.96, 95%CI:-13.22,-4.69), reduced cervical lordosis angle [°] (− 0.89, 95%CI:-1.72,-0.07), reduced pressure pain thresholds over the cranio-cervical region [kg/cm2], reduced neck extension strength [N] (− 11.13, 95%CI:-16.66,-5.6) and increased activity [%] of the trapezius (6.18, 95%CI:2.65,9.71) and anterior scalene muscles (2.87, 95%CI:0.81,4.94) during performance of the cranio-cervical flexion test; c) compared to controls, CGH patients exhibit decreased neck flexion (− 33.70, 95%CI:-47.23,-20.16) and extension (− 55.78, 95%CI:-77.56,-34.00) strength [N]. Conclusion The FRT and neck flexion strength could support the differential diagnosis of CGH from migraine. Several physical tests were found to differentiate both headache types from asymptomatic individuals. Nevertheless, additional high-quality studies are required to corroborate these findings. Study registration Following indications of Prisma-P guidelines, this protocol was registered in PROSPERO on 21/05/2019 with the number CRD42019135269. All amendments performed during the review were registered in PROSPERO, indicating the date and what and why was changed.

Effects of smartphone screen viewing duration and body position on head and neck posture in elementary school children

BACKGROUND: Electronic media have become integral parts of modern life, in which prolonged screen viewing time (SVT) by children is nearly unavoidable. Prolonged use of smartphones could lead to musculoskeletal problems. OBJECTIVES: To investigate the effect of SVT on head and neck posture during and after using smartphones for various periods of time in either standing or sitting postures. METHODS: This observational study included 34 male children aged 5–12 years who were assigned to one of two groups based on average smartphone use duration per day: group A comprised 18 children averaging > 4 hours per day (h/day) of smartphone use, and group B comprised 16 children with < 4 h/day of smartphone use. The children’s postures were photographed in standing and sitting positions while using a smartphone and 30 min after ceasing smartphone use. The head flexion, neck flexion, gaze, and craniocervical angles were measured using the software program Kinovea. RESULTS: Significant increases were found in head flexion, neck flexion, and gaze angles. Furthermore, both groups saw a significant decrease in craniocervical angle when sitting compared to when standing, both during and 30 min after smartphone use. The head flexion, neck flexion, and gaze angles of group A were significantly higher than those of group B, and the craniocervical angle of group A was significantly lower than that of group B in both postures (p< 0.05). CONCLUSION: SVT is associated with increased neck and head flexion posture in children, especially in a sitting position.