Introducing a new possible predisposing risk factor for odontoid type 2 fractures after cervical trauma; Ponticulus posticus anomaly of C1 vertebra

New experimental finding of dangerous autonomic ganglia changes in cardiac injury following subarachnoid hemorrhage; a reciprocal culprit-victim relationship between the brain and heart

OBJECTIVE

The vagal, stellate, and cardiac ganglia cells changes following subarachnoid hemorrhage (SAH) may occur. This study aimed to investigate if there is any relation between vagal network/stellate ganglion and intrinsic cardiac ganglia insult following SAH.

MATERIALS AND METHODS

Twenty-six rabbits were used in this study. Animals were randomly divided as control (GI, n = 5); SHAM 0.75 cc of saline-injected (n = 5) and study with autologous 1.5 cc blood injection into their cisterna magna(GIII, n = 15). All animals were followed for three weeks and then decapitated. Their motor vagal nucleus, nodose, stellate, and intracardiac ganglion cells were estimated by stereological methods and compared statistically.

RESULTS

Numerical documents of heart-respiratory rates, vagal nerve- ICG, and stellate neuron densities as follows: 276 ± 32/min-22 ± 3/min-10.643 ± 1.129/mm3-4 ± 1/mm3-12 ± 3/mm3 and 2 ± 1/cm3 in the control group; 221 ± 22/min-16 ± 4/min-8.699 ± 976/mm3-24 ± 9/mm3-103 ± 32/mm3 and 11 ± 3/cm3 in the SHAM group; and 191 ± 23/min-17 ± 4/min-9.719 ± 932/mm3-124 ± 31/mm3-1.542 ± 162/mm3 and 32 ± 9/cm3 in the SAH (study) group. The animals with burned neuro-cardiac web had more neurons of stellate ganglia and a less normal neuron density of nodose ganglia (p < 0.005).

CONCLUSION

Sypathico-parasympathetic imbalance induced vagal nerve-ICG disruption following SAH could be named as Burned Neurocardiac Web syndrome in contrast to broken heart because ICG/parasympathetic network degeneration could not be detected in classic broken heart syndrome. It was noted that cardiac ganglion degeneration is more prominent in animals' severe degenerated neuron density of nodose ganglia. We concluded that the cardiac ganglia network knitted with vagal-sympathetic-somatosensitive fibers has an important in heart function following SAH. The neurodegeneration of the cardiac may occur in SAH, and cause sudden death.Graphical abstract[Formula: see text].

How does the side of lumbar disc herniation influence the psoas muscle size at the L4-5 level in patients operated for unilateral hip arthroplasty?

Study Design: Retrospective study.

Objection: There can be a relationship between degenerative diseases in the spine and hip.

Summary of Background Data: Degenerative diseases in the spine and hip may occur concomitantly. This study was done to investigate the cross-sectional area of psoas muscle size and incidence of lumbar disc herniation after unilateral hip arthroplasty.

Methods: The data files of patients who were operated on for unilateral hip arthroplasty between January 2014- and 15 May 2021 at the Recep Tayyip Erdogan University Hospital were retrospectively analysed for the relationship between the psoas muscle volume and the incidence of lumbar disc herniation. The patients were divided according to their operated sides.

Results: The data files of 48 patients were retrospectively analysed. The patients were divided into two groups according to the operated side of their hip joints. Gender and age differences were not significant, and the mean ages were 68,68 years old in the right hip arthroplasty group, and 69,39 in the left hip arthroplasty group.

Conclusions: A complex interaction between the development of lumbar disc herniations and increased contralateral cross-sectional area of the psoas muscle at the L4-5 level was observed in patients operated for unilateral hip arthroplasty. This interaction can be a compensatory mechanism to counteract the spinal imbalance.

New Evidence for Regulatory Role of Trigeminal Ganglion on the Intraocular Pressure Following Subarachnoid Hemorrhage

BACKGROUND

 Increased intraocular pressure (IOP) likely secondary to an activated oculo-trigeminal reflex network is an important issue following subarachnoid hemorrhage (SAH). The relationship between the IOP and trigeminal ganglion (TGG) following experimental SAH was investigated in this study.

METHODS

 Twenty-three rabbits were used in this study. Five rabbits (n = 5) were used as the control group, another 5 as the sham group (n = 5), and the remaining 13 (n = 13) as the study group. The study group was further divided into two groups of animals with mild (n = 6) and severe (n = 7) TGG degeneration. The IOP values were recorded. After 2 weeks, the animals were decapitated. The mean degenerated neuron density of TGGs was estimated by stereological methods and analyzed statistically.

RESULTS

 The average IOP values were 11.85, 14.12, and 21.45 mm Hg in the control (n = 5), sham (n = 5), and study (n = 13) groups, respectively. The mean degenerated neuron density was 34, 237, and 3,165 mm3 in the control, sham, and study groups, respectively.

CONCLUSION

 According to the findings of this study, the experimental SAH leads to changes in IOP by affecting the TGG. By predicting and preventing IOP elevation in the setting of SAH, our findings will shed light on secondary sequelae such as glaucoma and irreversible blindness.

Overlooked evidence for transmission deficit of pupillary light reflex can be secondary to trigeminal nerve ganglion degeneration following subarachnoid hemorrhage; preliminary experimental study

OBJECTIVE

Although the effect of oculomotor and cervical sympathetic networks on pupil diameter is well known; the effect of the trigeminal nerve on pupil diameter has not been investigated yet. This subject was investigated.

MATERIALS AND METHODS

Five of 23 rabbits were used as a control group (GI; n = 5); 0.5 ccs saline solution into cisterna magna injected animals used as SHAM (GII; n = 5); autologous blood injected to produce SAH used as the study group (GIII; n = 13) and followed up three weeks. Light-stimulated pupil diameters were measured with an ocular tomography device before, middle, and at the end of the experiment. Considering the sclera area/pupil area ratio index (PRI) as the pupillary reaction area, we used this equation for the pupil's rush to light. Degenerated neuron densities of trigeminal ganglia and pupil diameters compared with the Mann-Whitney U test.

RESULTS

The PRI, degenerated neuron density of trigeminal ganglia (n/mm3) were: (2.034 ± 0.301)/(13 ± 3) in GI; (1.678 ± 0.211)/(46 ± 9) in GII; and (0.941 ± 0.136)/(112 ± 21) in GIII. P-values between groups as: p < 0.005 in GI/GII; p < 0.0001 in GII/GIII and p < 0.00001 in GI/GIII.

CONCLUSION

Light stimulates the cornea which is innervated by the trigeminal nerves. This experimental study indicates that the pupil remains mydriatic as the cornea is damaged by trigeminal ischemia following SAH and blocks the light flow.

From Nose to Lumbar Spinal Cord - Reduced Sperm Numbers Occur by Olfactory Bulbectomy-Related Onuf's Nucleus Degeneration: New Experimental Evidence for Kallmann Syndrome

INTRODUCTION

Olfaction and its relation to human health is an area of growing interest. Although olfaction disorders have been considered a part of Kallmann syndrome, the role of olfactory dysfunction on spermatogenesis has not been studied yet. We studied if olfactory bulbectomy (OBX) causes dysfunction in spermatogenesis as a result of Onuf's nucleus damage.

METHODS

Twenty-eight male rats were divided into three groups: six as the control (G-1; n = 6), six as the only frontal burr hole applied animals SHAM (G-2; n = 6), and 16 as the study group (G-3; n = 16) in which OBX was performed. The animals were followed for 2 months. After the decapitation of the animals, olfactory bulb (OB) volumes (mm3), the neuron density of the Onuf's nucleus (n/mm3), and sperm density (n/mm3) were estimated stereologically and analyzed.

RESULTS

OB volumes (mm3), degenerated neuron density of Onuf's nucleus (n/mm3), and sperm numbers of control, SHAM, and study groups were estimated as: 4 ± 0.5; 6 ± 2 and 103.245 ± 10.841 in G-1; 3.5 ± 0.7; 14 ± 4 and 96.891 ± 9.569 in G-2; and 1.3 ± 0.3; 91 ± 17 and 73.561 ± 6.324 in G-3. The statistical results of degenerated neuron density of Onuf's nucleus and sperm numbers between groups are p < 0.005 for G-1/G-2; p < 0.0005 for G-2/G-3; and p < 0.00001 for G-1/G-3.

DISCUSSION

This study first time indicates that Onuf's nucleus degeneration secondary to OBX seems to be responsible for reduced sperm numbers.

Could the Cerebral Involvement of COVID-19 Disease be Related to Microstructural Changes that are not Reflected in Conventional MRI Images?

In patients with COVID-19, neurodegeneration may develop before clinical symptoms appear. Diffusion-weighted (DW) MRI is an important technique for analyzing microstructural changes such as gliosis. In this study, a quantitative evaluation of microstructural changes in the brain with apparent diffusion coefficient (ADC) values in patients presenting with a headache after the COVID-19 disease was analyzed and compared. DW MR images of patients of 20 COVID-19 patients (13 females, 7 males) who required imaging due to headache; 20 controls (16 females, 4 males) were retrospectively reevaluated. ADC measurements were taken from 16 regions of the brain, including right and left symmetrical in patients with COVID-19 infections and control groups. All regions of interest (ROIs) were taken from the hypothalamus, parahippocampus, thalamus, corpus striatum, cingulate gyrus, occipital gyrus, dentate nucleus, and medulla oblongata posterior. ADC values in the dentate nucleus right (784.6 ± 75.7 vs. 717.25 ± 50.75), dentate nucleus left (768.05 ± 69.76 vs. 711.40 ± 52.99), right thalamus (731.15 ± 38.14 vs. 701.60 ± 43.65), left thalamus (744.05 ± 39.00 vs. 702.85 ± 28.88), right parahippocampus (789.10 ± 56.35 vs. 754.75 ± 33.78), right corpus striatum (710.00 ± 39.81 vs. 681.55 ± 39.84) were significantly higher than those in the control group. No significant changes were observed in other areas. A significant increase in ADC values at many levels in the brain in patients with COVID-19 disease and headache was observed. Thus, this study indicates that cerebral involvement in COVID-19 disease may be related to microstructural changes that are not reflected in conventional MRI images.

Age- and gender-related radiological changes of the cervical spine: A study with largest magnetic resonance imaging database of 5672 consecutive patients

Background

The morphological features of the cervical spine are an essential issue. This retrospective study aimed to investigate the structural and radiological changes in the cervical spine.

Materials and Methods

A total of 250 patients with neck pain but no apparent cervical pathology were selected from a database of 5672 consecutive patients undergoing magnetic resonance imaging (MRI). MRIs were directly examined for cervical disc degeneration. These include Pfirrmann grade (Pg/C), cervical lordosis angle (A/CL), Atlantodental distance (ADD), the thickness of transverse ligament (T/TL), and position of cerebellar tonsils (P/CT). The measurements were taken at the positions of T1- and T2-weighted sagittal and axial MRIs. To evaluate the results, patients were divided into seven age groups (10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70, and over).

Results

In terms of ADD (mm), T/TL (mm), and P/CT (mm), there was no significant difference among age groups (P > 0.05). However, in terms of A/CL (degree) values, a statistically significant difference was observed among age groups (P < 0.05).

Conclusions

Intervertebral disc degeneration was more severe in males than in females as age increased. For both genders, cervical lordosis, decreased significantly as age increased. T/TL, ADD, and P/CT did not significantly differ with age. The present study indicates that structural and radiological changes are possible reasons for cervical pain at advanced ages.

Biomechanical analysis of odontoid and transverse atlantal ligament in humans with ponticulus posticus variation under different loading conditions: Finite element study

PURPOSE

Ponticulus posticus (PP) is a variation of the bone bridge that appears in the first cervical vertebra and through which the vertebral artery passes. Odontoid fractures are common spinal bone fractures in older people. This study aims to investigate the effect of neck movements on the odontoid and transverse atlantal ligament (TAL) of people with PP variation from a biomechanical view.

METHOD

C1, C2, and C3 vertebrae of the occipital bone were analyzed using the finite element method (FEM). In this study, solid models were created with the help of normal (N), incomplete (IC), and asymmetric complete (AC) PP tomography images. The necessary elements for the models were assigned, and the material properties were defined for the elements. As boundary conditions, models were fixed from the C3 vertebra, and 74 N loading was applied from the occipital bone. Stress and deformation values in the odontoid and transverse atlantal ligament were obtained by applying 1.8 Nm moment in flexion, extension, bending, and axial rotation directions.

RESULTS

The stress and deformation values of all three models in odontoid and TAL were obtained, and numerical results were evaluated. In all models, stress and deformation values were obtained in decreasing order in rotation, bending, extension, and flexion movements. The highest stress and strain values were obtained in AC and the lowest values were obtained in N. In all movements of the three models, the stress and deformation values obtained in the TAL were lower than in the odontoid.

CONCLUSION

The greatest stresses and deformations obtained in spines (AC) with PP were found in the odontoid. This may help explain the pathogenesis of odontoid fractures in older people. First, this study explains the mechanism of the formation of neck trauma in people with PP and the need for a more careful evaluation of the direction of impact. Secondly, the study reveals that the rotational motion of the neck independent of PP has more negative effects on the odontoid.

Does the anesthesia technique of cesarean section cause persistent low back pain after delivery? A retrospective analysis

OBJECTIVE

Cesarean sections (CS) under spinal anesthesia may lead to newly developed low back pain (LBP) after anesthesia. The cause of this pain is still unknown. This subject was investigated.

METHODS

The persistent LBP after the section was retrospectively analyzed in patients who were operated on under spinal or general anesthesia between January 1, 2018, and January 1, 2020.

RESULT

General anesthesia was used in 52 women, but 251 women were operated on under spinal anesthesia. Newly developed persistent LBP was detected in 57 (18,8%) of a total of 303 patients. Of those patients with LBP, general anesthesia was used in 14 of 52 (26,9%) patients, but 43 of 251 (17.1%) patients received spinal anesthesia. Baby weight after CS was the only variable associated with persistent LBP after 3 and 6 months (P < 0.05) in multiple logistic regression analysis. Patient age and anesthesia type were not associated with persistent LBP (P > 0.05).

CONCLUSION

This study shows anesthesia type as spinal or general was not associated with increased persistent LBP. Performing more spinal than general anesthesia in the cesarean section may be false data about the increased rate of LBP after CS.

Protective Felix-Culpa Effect of Superior Sympathetic Cervical Ganglion Degenerations on Prevention of Basilar Artery Spasm Following Subarachnoid Hemorrhage: A Preliminary Experimental Study

BACKGROUND

Posterior cerebral blood flow is regulated by the basilar arteries (BA). Its vasospasm of basilar arteries (BA) can occur following subarachnoid hemorrhage (SAH). Superior cervical sympathetic ganglia (SCG) fibers have a vasoconstrictor effect on the BA. We aimed to investigate the relationship between the degenerated neuron density of the SCG and the severity of BA vasospasm after experimental subarachnoid hemorrhage.

METHODS

Twenty-four rabbits were used. Five of them were used as the control group, and five of them were used as the SHAM group. Experimental subarachnoid hemorrhages were performed in the remaining fourteen animals (study group) by injecting homologous blood into cisterna magna. After three weeks of injection, neuron densities of SCG and the severity of BA vasospasm index values (VSI) were examined histopathologically and compared statistically.

RESULTS

The mean VSI was 0.669±0.1129 in the control group, 0.981±0.159 in the SHAM group, and 1.512±0.298 in the study group. The mean degenerated neuronal density of SCG was 436±79/mm³ in severe vasospasm (n=3), 841±101/mm³ in moderate vasospasm (n=4), and 1.921±849/mm³ in the less vasospasm detected animals (n=6).

CONCLUSION

This study shows an inverse relationship between the degenerated neuronal density in the SCG and VSI values. This finding indicates a diminished sympathetic input from the superior cervical ganglion (SCG) resulting in a beneficial (the Felix-culpa) effect by dilating the lumen diameter of the basilar artery (BA), so superior sympathetic cervical ganglion degeneration following SAH protects the basilar artery spasm.

Full-Endoscopic Anterior Odontoid Screw Fixation: A Novel Surgical Technique

OBJECTIVE

First, to propose a novel minimally invasive technique of full-endoscopic anterior odontoid fixation (FEAOF) that aims to reduce the risk of retropharyngeal approach (both open and percutaneous techniques) to anterior odontoid screw fixation. Second, to describe steps of the procedure and, lastly, to report the initial outcomes in patients treated with this novel technique.

METHODS

Four non-consecutive patients who were diagnosed with a displaced odontoid fracture (Anderson-D'Alonzo classification type II and Grauer subclassification type A or B) from 2019 to 2020 underwent surgical fixation by our novel technique for anterior odontoid screw fixation. A detailed technical approach of FEAOF for the surgical treatment of type II odontoid fractures was described, and the patients' outcomes based on postoperative radiographic results including computed tomography (CT), clinical outcome parameters including visual analogue scale (VAS) for neck pain both preoperatively and at postoperative follow-up, and range of neck motion at the final follow-up were reported.

RESULTS

The mean age was 33.5 years (24-41), three patients were male. The mean operative time was 93.75 min, and the mean blood loss was 7.5 ml. An immediate post-operative thin-sliced CT showed that all patients achieved satisfactory reduction and proper screw position. No screw malposition or penetration was found. At a 6-month follow-up, a thin-sliced CT demonstrated solid bony union in every case. The mean VAS for neck pain was reduced from 6.5 to 0.6 at the 6-months follow-up. At the final follow-up, all patients showed improvement in ranges of motion without any complications; however, one patient was lost to follow-up.

CONCLUSIONS

FEAOF is a feasible and effective option for treating type II odontoid fractures. The procedure is less invasive than other techniques and provides clear direct visualization of the involved structures.

Research Progress of Ponticulus Posticus: A Narrative Literature Review

Study Design

Narrative review.

Objective

The purpose of this review was to consolidate the current literature related to ponticulus posticus (PP) and to improve the systematic understanding of this anatomical variant of atlas among spine surgeons.

Methods

Articles reviewed were searched in PubMed, Ovid MEDLINE, and Embase. All articles of any study design discussing on PP were considered for inclusion. Two independent authors read article titles and abstracts and included appropriate articles. The relevant articles were studied in full text.

Results

A total of 113 literatures were reviewed and consolidated in this narrative review. These articles are roughly divided into the following five subcategories: (1) epidemiology, (2) pathology and anatomy, (3) clinical presentation, (4) surgical significance, and (5) radiographic examination.

Conclusion

The PP is non-negligible with a high prevalence. The PP compresses the V3 segment of the artery, the suboccipital nerve, and the venous plexus, consequently contributing to the incidence of neurological pathologies. When a PP is observed or suspected on a lateral radiograph, we recommend that a computed tomography (CT) scan of a patient who is about to receive a C1 lateral mass screw (C1LMS) should be performed, which could determine a safe entry point and the right trajectory of screw insertion.