C2 Vertebra Research Articles

Dysphagia in Head and Neck Radiotherapy: The Influence of Pharyngeal Constrictor Anatomy and Dosimetry.

The goal of this study was to identify which anatomical and dosimetric changes correlated with late patient-reported dysphagia throughout the course of head and neck chemo-radiotherapy treatment. The patient cohort (n = 64) considered oropharyngeal and nasopharyngeal patients treated with curative intent, exhibiting no baseline dysphagia with a follow-up time greater than one year. Patients completed the MD Anderson Dysphagia Inventory during a follow-up visit. A composite score was measured ranging from 20 to 100, with a low score indicating a high symptom burden; a score ≤60 indicated patient-reported dysphagia. The pharyngeal (PCM) and cricopharyngeal constrictor muscles (CPM) were contoured on a planning CT image and adapted to weekly cone-beam CT anatomy using deformable image registration and dose was accumulated using weighted dose-volume histogram curves. The PCM and CPM were examined for volume, thickness, and dosimetric changes across treatment with the results correlated to symptom group. Anatomical evaluation indicated the PCM thickness increased more during treatment for patients with dysphagia, with base of C2 vertebrae (p = 0.04) and superior-inferior middle PCM (p = 0.01) thicknesses indicating a 1.0-1.5mm increase. The planned and delivered mean dose and DVH metrics to PCM and CPM were found to be within random error measured for the dose accumulation, indicating delivered and planned dose are equivalent. The PCM and CPM organs were found to lie approximately 5mm closer to high dose gradients in patients exhibiting dysphagia. The volume, thickness, and high dose gradient metrics may be useful metrics to identify patients at risk of late patient-reported dysphagia.

Nasopharyngeal carcinoma in a young adolescent with unilatral palatal palsy and neck mass – A rare case report

Less than 1% of all head and neck neoplasms are juvenile nasopharyngeal angiofibromas, a cancer almost exclusively found in adolescent males. Here we present a case report of 14 year old male presented with neck swelling, nasal discharge mixed with blood, right sided proptosis and right sided palatal palsy where we performed CECT scan of the patient which showed homogenous opacity over nasopharynx extending to soft palate and posteriorly to C1 vertebra and DNE was performed. Later patient was planned for DNE along with biopsy which came out to be undifferentiated non-keratinized squamous cell carcinoma grade III. Further patient received external beam intensity modulated radiation therapy with complete response to treatment.

Regular patterns in the size ratio of the cervical vertebral bodies registered by MRI in the axial plane

Aim – to find regular patterns in the morphometric characteristics for the bodies of the cervical vertebrae when performing measurements in the axial (transverse) plane in men and women with different severity of degenerative-dystrophic changes of the cervical spine. Material and methods. The material of the study was the tomograms of 75 men and 128 women aged 18 to 84 years, obtained on magnetic resonance tomographs with a magnetic field strength of 1 Tl and 1.5 Tl. The data was divided into several groups according to the patients' sex and severity of degenerative-dystrophic changes of the cervical spine. The length and width of the vertebral bodies in the axial plane were measured with the subsequent calculation of their ratio. Results. Significant differences were found between the 1st and 2nd groups for the width of C7-C4 in women, as well as for the length of C3 and width of C3, C2 in men. Significant difference in the ratio of the sizes of vertebral bodies was registered in the 1st and 2nd groups of women at the level of C7. When comparing the data of all observation groups among men, significant differences were noted in the 2nd and 3rd groups for C7, C6, C3. With progression of degenerative-dystrophic changes, the differences in length were significant for C7-C4, C2 vertebrae in the 1st group, for C7-C5, C2 – in the 2nd and C7, C6, C4-C2 in the 3rd group. In the group of men with pronounced changes in the cervical spine region, in most cases there was an increase in coefficients (with significant differences in data for the 2nd and 3rd groups). Conclusion. Among men, significant differences were observed between the 2nd and 3rd groups for C7, C6, C3. For the C2 vertebra, significant differences were noted, taking into account sex, for length in the 1st and 3rd groups, width – in the 1st and 2nd groups, when assessing the mutual ratio of the sizes of the vertebral bodies – in the 2nd and 3rd groups.

Biomechanical Analysis of Trapezoidal Thread Screw-Rod Fixation in Pedicle Section of Cervical Spine: A Finite-Element Analysis.

Cervical pedicle screw-rod fixation presents a complex approach in spinal surgery, offering enhanced spine stabilization in variable conditions considering traumatic injuries, degenerative changes, as well as orthopaedic and oncological ailments. This technique employs small diameter screw implants strategically placed to bolster the mechanical integrity of the spine. Notably, it involves minimally invasive procedures, resulting in smaller incisions and reduced patient discomfort. This study aims to assess the effects of trapezoidal thread screws in pedicle sections of the cervical spine during flexion-extension loadings, focusing on factors such as range of motion (ROM), implant stress, and stress on adjacent bone. Utilizing CT scan data, a finite element model of the cervical spine (C2-C7 vertebrae) was prepared. Trapezoidal thread screws were integrated into a single-level pedicle screw-rod fixation at the C5-C6 vertebrae. The C2 vertebra were given a compressive load of 50 N along with a moment of 1 Nm, resulting in the immobilization of the C7. The results indicate a reduction in ROM at the C5-C6 level by 69% to 77% compared to the intact spine during flexion-extension loading, with a slight increase in ROM observed at adjacent cervical spine levels. Stress analysis revealed that the trapezoidal thread screws induced stresses ranging from 24 MPa to 29 MPa in PEEK trapezoidal screw-rod implants, which fall below the material's yield stress. This suggests that the trapezoidal thread profile may be advantageous in minimizing stress concentration, attributed to its larger contact area with the vertebrae bone between the threads.

Ganglionic Local Opioid Analgesia at the Superior Cervical Ganglion: MRI-Verified Solution Spread.

Ganglionic local opioid analgesia (GLOA) at the superior cervical ganglion (SCG) is performed for pain control and is known to be an effective procedure. In this study, we evaluated the spread of the injectate in the area of the SCG. Our expectation was that there would be a correlation between the area and volume of the injectate spread and post-procedural outcome measures. This was a retrospective blinded review of magnetic resonance imaging (MRI) scans. Assessors evaluated the anatomical area of fluid spread, the furthermost spread from midline, any hampered spread and contact of contrast fluid with other structures. The efficacy of GLOA and complications were estimated. The main solution spread reached from the C1 to C3 vertebrae. The furthest spread in the lateral and sagittal planes was 21.2 and 15.2mm, respectively. The furthest craniocaudal spread was 63.5mm. In 53.3% and 33% of interventions, the solution was found in the parapharyngeal space and in its "medial compartment," respectively. A correlation was found between pain relief and both solution spread and volume of solution spread. No hampered spread was recorded. A negative correlation between pain reduction and number of GLOA was observed. Higher pre-procedural pain intensity was correlated with higher pain reduction. We estimated pain relief in 93% of procedures correctly. No correlation between post-procedural Numerical Rating Scale (NRS) scores and different needle approaches was found. For the transoral blocking technique, a strict laterodorsal needle direction is recommended to prevent possible block failures. A total volume of 2ml injected into the parapharyngeal space and its "medial compartment" is recommended. Higher volumes may lead to uncontrolled distribution patterns. Clinicaltrials.gov identifier NCT05257655; date of registration 2022-02-25; patient enrollment date from 2023-01-09 to 2023-08-31.

Finite Element Analysis Comparing the Biomechanical Parameters in Multilevel Posterior Cervical Instrumentation Model Involving Lateral Mass Screw versus Transpedicular Screw Fixation at the C7 Vertebra.

Basic research. This finite element (FE) analysis (FEA) aimed to compare the biomechanical parameters in multilevel posterior cervical fixation with the C7 vertebra instrumented by two techniques: lateral mass screw (LMS) vs. transpedicular screw (TPS). Very few studies have compared the biomechanics of different multilevel posterior cervical fixation constructs. Four FE models of multilevel posterior cervical fixation were created and tested by FEA in various permutations and combinations. Generic differences in fixation were determined, and the following parameters were assessed: (1) maximum moment at failure, (2) maximum angulation at failure, (3) maximum stress at failure, (4) point of failure, (5) intervertebral disc stress, and (6) influence of adding a C2 pars screw to the multilevel construct. The maximum moment at failure was higher in the LMS fixation group than in the TPS group. The maximum angulation in flexion allowed by LMS was higher than that by TPS. The maximum strain at failure was higher in the LMS group than in the TPS group. The maximum stress endured before failure was higher in the TPS group than in the LMS group. Intervertebral stress levels at C6-C7 and C7-T1 intervertebral discs were higher in the LMS group than in the TPS group. For both models where C2 fixation was performed, lower von Mises stress was recorded at the C2-C3 intervertebral disc level. Ending a multilevel posterior cervical fixation construct with TPS fixation rather than LMS fixation at the C7 vertebra provides a stiff and more constrained construct system, with higher stress endurance to compressive force. The constraint and durability of the construct can be further enhanced by adding a C2 pars screw in the fixation system.

The clay-shoveler’s fracture, a rare occupational injury in the modern era: a case report

BackgroundThe clay-shoveler fracture, named after Australian clay shovelers from the 1930s, results from high-energy, repetitive pulling mechanisms and is commonly associated with shoveling or digging. This injury primarily affects the lower cervical and upper thoracic vertebrae, particularly the C7 and T1 vertebrae. The avulsion mechanism, caused by stress on the spinous processes, may lead to sudden, severe upper back pain, limiting the affected individual’s ability to work effectively.Case presentationThis report presents the case of a 27-year-old boiler operator who experienced persistent neck pain, which did not respond to conservative management. Imaging studies revealed a T1 spinous process fracture with associated soft tissue edema, diagnosed as a clay-shoveler fracture. Conventional treatment with a semirigid cervical collar, analgesia, and rest was administered, leading to a favorable outcome.The clay-shoveler fracture, though rare, should be considered in cases involving repetitive stress on the cervical and thoracic spine, especially in occupations that require heavy lifting. In most instances, conservative management proves effective in relieving pain and enabling recovery.ConclusionRecognizing the clay-shoveler fracture is crucial for timely diagnosis and treatment. This case report underscores the occupational nature of the injury and its association with specific work activities. Further research and reporting of similar cases will contribute to a deeper understanding of this unusual fracture pattern, its risk factors, and optimal management strategies.

Approach for contact medical device development via integrated testing, skeletal muscle modeling, and finite element analysis

Development of novel medical devices for the treatment of musculoskeletal pain associated with neuro-muscular trigger points requires a model for relating the mechanical responses of in vivo biological tissues to applied palliative physical pressures and a method to design treatments for optimal effects. It is reasonable to hypothesize that the efficacy of therapeutic treatment is proportional to the maximum tensile strain at trigger point locations. This work presents modeling of the mechanical behavior of biological tissue structures and treatment simulations, supported by indentation experiments and finite element (FE) modeling. The steady-state indentation responses of the tissue structure of the posterior neck were measured with a testing device, and an FE model was constructed using a first-order Ogden hyperelastic material model and calibrated with the experimental data. The error between experimental and FE-generated displacement-load curves was minimized via a two-stage optimization process comprised of an Optimal Latin Hypercube design-of-experiments analysis and a Bayesian optimization loop. The optimized Ogden model had an initial shear modulus (μ) of 5.16 kPa and a deviatoric exponent (α) of 11.90. Another FE model was developed to simulate the deformation of the tissue structures in the posterior neck adjacent to the C3 vertebrae in response to indentation loading, in order to determine the optimal location and angle to apply an indentation force for maximum therapeutic benefit. The optimal location of indentation was determined to be 28° lateral from the sagittal plane along the surface of the skin, measured from the centerline of the spine, at an angle of 8° counterclockwise from the surface normal vector. The optimized spatial orientation of the indentation corresponded to the average of the maximum principal strain across the deep muscle region of the model.

Type Id versus type IId three-level hybrid surgery for the treatment of noncontiguous cervical spondylosis: A finite element analysis

The objective of the research is to simulate different forms of three-level hybrid surgeries, aiming to establish a foundational reference for the selection of suitable treatment strategies for multilevel noncontiguous cervical degenerative disease (CDD). For the development of precise finite element models (FEMs), this study utilized computed tomography (CT) data. Two cross-segment surgical approaches were primarily investigated: C3/4 cervical disc arthroplasty (CDA), C5/6 anterior cervical discectomy and fusion (ACDF), and C6/7 ACDF in the type Id model; C3/4 CDA, C5/6 CDA, and C6/7 ACDF in the type IId model. The follower load technique was employed to apply an initial axial load of 73.6 N at the motion center. Subsequently, a moment of 1.0 Nm was introduced at the center of the C2 vertebra to simulate the overall motion of the model. In contrast to type IId, type Id exhibited lower average intervertebral disc pressure in C4/5 across various motions. The average intervertebral disc pressure in C2/3 was higher in type Id compared to type IId in flexion and axial rotation, whereas the reverse was observed in lateral bending. Type IId exhibited notably lower facet joint contact stresses during extension in C2/3 and C4/5 when compared to type Id. Type Id has a better protective effect on IS, and can significantly reduce the average pressure of the intervertebral disc in IS compared with type IId. Type IId has a significant protective effect on the post-column structure of non-fused segments.

Posterolateral Paramass Approach to Lesions Located at the Anterior C1-2 Level: A Cadaver Study

A novel posteriolateral surgical approach is described that will provide safe access to intradural and extradural lesions located in the anterior part of the spinal cord (SC) at the C1-2 level and to the odontoid in single session. A total of five cadavers and two dry C1 vertebrae were used in this study. The study involved obtaining computed tomography magnetic resonance imaging scans and magnetic resonance imaging of all cadaver groups before and after the procedures. Group 1: Control; Group 2: Unilateral C1 posterior arch was removed, the inferomedial part of C1 lateral mass was removed, and access the anterior and lateral aspects of the SC. Group 3: In addition, odontoid was removed, Group 4: In addition, unilateral C1- C2 screw was placed. Group 5: In addition, bilateral C1-C2 screw was placed. The median distance from the midpoint of C1 posterior tubercle to vertebral groove which was removed in groups is 21.4 ± 2.88mm. The average width of C1 lateral mass was 13.4±2.4mm. After the lateral mass was drilled, its width decreased to 10,2mm.This area was sufficient to open a surgical corridor and reach the anterior of SC and odontoid. After the procedure, no instability was found in group 2 without instrumentation on computed tomography and magnetic resonance imaging scans. It is possible to access the anterior C1-C2 via a posterolateral paramass approach by drilling 20%-30% of the lateral mass, providing an open pathway for easy intervention in C1-C2 intradural lesions. It is also possible to perform odontoid resection using this approach.

Segment selection for fusion and artificial disc replacement in the hybrid surgical treatment of noncontiguous cervical spondylosis: a finite element analysis.

Introduction: The treatment of skip-level cervical degenerative disease (CDD) with no degenerative changes observed in the intervening segment (IS) is complicated. This research aims to provide a reference basis for selecting treatment approaches for noncontiguous CDD. Methods: To establish accurate finite element models (FEMs), this study included computed tomography (CT) data from 21 patients with CDD (10 males and 11 females) for modeling. The study primarily discusses four cross-segment surgical approaches: upper (C3/4) anterior cervical discectomy and fusion (ACDF) and lower (C5/6) cervical disc arthroplasty (CDA), FA model; upper CDA (C3/4) and lower ACDF (C5/6), AF model; upper ACDF (C3/4) and lower ACDF (C5/6), FF model; upper CDA (C3/4) and lower CDA (C5/6), AA model. An initial axial load of 73.6 N was applied at the motion center using the follower load technique. A moment of 1.0Nm was applied at the center of the C2 vertebra to simulate the overall motion of the model. The statistical analysis was conducted using STATA version 14.0. Statistical significance was defined as a p value less than 0.05. Results: The AA group had significantly greater ROM in flexion and axial rotation in other segments compared to the FA group (p < 0.05). The FA group consistently exhibited higher average intervertebral disc pressure in C2/3 during all motions compared to the AF group (p < 0.001); however, the FA group displayed lower average intervertebral disc pressure in C6/7 during all motions (p < 0.05). The AA group had lower facet joint contact stresses during extension in all segments compared to the AF group (p < 0.05). The FA group exhibited significantly higher facet joint contact stresses during extension in C2/3 (p < 0.001) and C6/7 (p < 0.001) compared to the AF group. Discussion: The use of skip-level CDA is recommended for the treatment of non-contiguous CDD. The FA construct shows superior biomechanical performance compared to the AF construct.

Percutaneous full-endoscopic bullet removal from the C2 vertebra in a pediatric patient.

Gunshot injuries (GSIs) to the spine constitute approximately 17% to 21% of all traumatic spinal injuries, with the cervical spine being the second most frequently affected region. There is a lack of approved algorithms for patients with GSIs to the spine. Surgical intervention is controversial; however, it is generally considered in cases involving neurological deterioration with incomplete deficit, externalized liquor fistula, instability, installed toxicity, and risk of migration. Detailed information on pediatric patients is limited, primarily due to the predominance of adult patients. This study presents the full-endoscopic removal of a bullet in the C2 vertebra of a pediatric patient. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23230.

ОСОБЕННОСТИ КЛИНИЧЕСКИХ ПРОЯВЛЕНИЙ ПРИ МАЛЬФОРМАЦИИ КИАРИ 0, 1 И «ПОГРАНИЧНОГО» ТИПОВ

Introduction. Introduction of advanced neuroimaging methods has made it possible to identify subtle structural features of the posterior cranial fossa and craniovertebral junction, as well as the dislocation of cerebellar tonsils into the foramen magnum, which have clinically overt and subclinical forms. Aim: To study the clinical manifestation features of Chiari type 0, 1, and “borderline” malformations. Materials and Methods. For literature analysis, the sources were used from international databases, such as Web of Science, Scopus, and PubMed, and the Russian library system, eLibrary. Results and Discussion. The most common pathology of the posterior cranial fossa is Chiari type 1 malformation associated with a mesodermal defect and with discrepancies between the sizes of the posterior cranial fossa and the neural structures that fill it. To assess the Chiari malformation grade, it is advisable to specify the dislocation grades of cerebellar tonsils. There is a common classification of cerebellar tonsil dislocations, in which the dislocation grade 1 of cerebellar tonsils is characterized by the descent of cerebellar tonsils below the foramen magnum level; grade 2 is inherent in dislocation of the cerebellar tonsils down to the C2 vertebra level in combination with displacing the pons and medulla oblongata below the Twining line. Grade 3 dislocation of the cerebellar tonsils is where the cerebellum tonsil displacement is combined with intracranial hypertension. In case of the degree 4 dislocation of the cerebellar tonsils, cerebellar hypoplasia is observed, accompanied by a displacement of the medulla oblongata. The occurrence of syringomyelia in Chiari type 0 malformation is associated with liquor dynamic disorders in the craniovertebral junction region; the similar liquor circulation disorders are detected in Chiari type 1 malformation. Chiari type 1 and “borderline”- type malformations manifest as persistent cranialgia, pain in the cervical spine, otoneurologic and visual disorders, respiratory, psychological, and cognitive disorders, damage to the cerebellar and stem structures of the brain, damage to the spinal cord, and other, more rare signs of damage to the central nervous system. Conclusions. Thus, it is necessary to further study the features of developing clinical symptoms in Chiari type 1, 0, and “borderline” malformations to assess the changes in the course of the disease and select an adequate treatment strategy.

Atlantoaxial subluxation and Down syndrome: A cross-sectional analysis.

Atlantoaxial subluxation (AAS) is a diagnosis describing misalignment of the C1 vertebra relative to C2. Excessive translation of this joint, located adjacent to the medullary brain stem, can lead to devastating neurological consequences. A higher prevalence of AAS within the Down syndrome (DS) population has been well-established. This study aims to establish a prevalence rate of DS in patients hospitalized for AAS and compare outcomes between AAS patients with and without DS. This study utilized the National Inpatient Sample (NIS) provided by the Healthcare Cost and Utilization Project (HCUP). In accordance with HCUP 2023 Clinical Classifications Software Refined files, data were queried using the International Classification of Diseases 10th Edition codes for DS and AAS. Demographics, comorbidities, hospital course, and outcomes were examined and compared using binary and linear multivariate regression. IBM SPSS software was used for data analysis. Of the 213,095 patients in the NIS database admitted between 2016 and 2020 with AAS as their primary diagnosis, 7.2% were DS patients. DS patients were significantly younger (26.56 ± 20.81 vs. 49.39 ± 27.63, P < 0.01), less likely to be female (33.30% vs. 52.10%), and had fewer comorbidities (diabetes mellitus, hypertension, and hyperlipidemia) than non-DS patients. There was no significant difference in likelihood to undergo surgical fusion between DS patients and non-DS patients with AAS. This large-scale study using NIS data determined that 7.2% of all patients admitted to hospitals for AAS are DS patients. The analysis of demographics, hospital course, and outcomes can influence the development of treatment protocols for AAS in the DS population.

Anesthetic management of completion thyroidectomy with sternal resection and reconstruction in a patient with difficult airway with C3 vertebrae body fracture

Anesthetic management of completion thyroidectomy with sternal resection and reconstruction in a patient with difficult airway with C3 vertebrae body fracture

Establishing Safe Surgical Parameters for Placement of C2 Pedicle Screws: A Retrospective Study.

The study aimed to evaluate the safety and feasibility of transpedicular instrumentation for the C2 vertebra and to establish the precise anatomical parameters and boundaries within which this procedure can be safely and effectively performed. This retrospective study analyzed 66 patients who underwent C2 transpedicular screw fixation. Preoperative and postoperative axial, sagittal, and coronal computed tomography (CT) scans were examined. Anatomical measurements were taken to determine the horizontal and vertical distances from the C2 pedicle projection to the vertebral foramen using CT images. Based on the anatomical location of the vertebral artery within the C2 vertebral foramen, the patients were divided into four subgroups using the horizontal pedicle width (HPW) and vertical pedicle width (VPW) of the C2 spine. The average age of the patients included in the study was 46.48 years. The patient population comprised 32 (48.5%) males and 34 (51.5%) females. Based on the anatomical measurements, the distribution of C2 vertebra types was as follows: type 1 accounted for 68.9%, type 2 for 3.8%, type 3 for 16.7%, and type 4 for 10.6%. Significantly narrower pedicle widths were observed in types 2 and 4 compared to other vertebra types. Type 2 had the largest medial angle (MA), while type 4 had the narrowest MA. In terms of the sagittal plane, type 4 exhibited the widest MA and type 3 had the narrowest MA, but these differences were not statistically significant. Among the cases, 12 (18.1%) involved the vertebral foramen, with 1 case (8.3%) showing screw-related vertebral artery injury (0.75% of all screws). No vertebral artery injuries were observed with the other transpedicular screws. Preoperative anatomical measurements for patients undergoing transpedicular instrumentation on the C2 vertebra should include planning CT images on three planes: axial, sagittal, and coronal.

Epidemiological Study of Traumatic Brain and Spinal Injuries in a Pediatric Population: A One-Year Analysis of Prevalence, Causes and Trends.

Background Traumatic brain injury (TBI) and spinal cord injury (SCI) are leading causes of morbidity and mortality in pediatric patients. However, the epidemiology of pediatric brain and spine injuries in Bulgaria is poorly documented. This study aims to analyze and identify the prevalence, causes, and trends of traumatic brain and spinal cord injuries in pediatric patients during the period of 1st June 2022 to 30th June 2023. Methods A retrospective study was conducted on the medical records of patients under 18 years of age who visited the emergency department of University Multiprofile Hospital for Active Treatment (UMHAT) Burgas, Bulgaria between 1st June 2022 and 30th June 2023. The incidence and etiology were stratified by age, gender, and anamnesis.Data processing and analysis were performed with the statistical package IBM SPSS v. 26.0 (IBM Corp., Armonk, NY, USA), and graphical analysis with MS Office Excel 2016 (Microsoft, Redmond, WA, USA). Means ± standard deviation and 95% confidence interval were calculated. All p-values less than 0.05 were considered indicative of statistical significance. Results Data for patients aged <18 years, admitted to the emergency department (ED) of UMHAT Burgas, Bulgaria from 1st June 2022 to 30th June 2023 were analyzed (n=38504). Of these patients, 32% were children (n=13857). One hundred thirty-four (0.3%) of the pediatric patients were hospitalized in the neurosurgical ward, and 4653 (10.7%) were hospitalized in other wards. Of the analyzed patients, 89 are boys (66.4%), 45 are girls (33.6%) (male-female ratio 2:1) and the mean age of the patients with a head trauma was 8.07 years old. The average number of patients by diagnosis is 13.4±35.37. The largest percent are patients with brain concussion (85.07%, n=114), followed by contusion of the nerve roots in the lumbar region or late contusion wound of the head (with 2.99% each, n=4); hydrocephalus or skull fracture (with 2.24% each, n=3); contusion of the nerve roots in the thoracic region (1.49%, n=2); and fracture at Th9 vertebrae, fracture at C2 vertebrae, brain trauma or brain tumor (with 0.75% each, n=1). The average number of patients by anamnesis is 13.2±17.99.The largest percent are patients who fall from their own height (44.78%, n=60); followed by falls from height (20.90%, n=28); car accident (7.46%, n=10); injured by fight, fall from a bicycle or incident during a football game (with 5.97% each, n=8); fall from electric scooter (4.48%, n=6); hit in the closet (2.99%, n=4); and finally from bike accident or hit by a rock (with 0.75% each, n=1). From 134 hospitalized patients in neurosurgery, 114 (85.07%) did not require surgical treatment and were treated with conservative treatment and 20 (14.93%) were treated surgically. Conclusion In conclusion, this study highlights a significant burden of pediatric traumatic brain and spinal injuries in Bulgaria. The majority of cases were managed conservatively, emphasizing the need for preventive measures.

Long-term results of treatment of a patient with basilar invagination complicated by distal kyphosis and compressive ischemic cervical myelopathy: a clinical case and a brief literature review

Objective. To present a clinical case of surgical correction of a craniovertebral anomaly complicated after 8 years by distal junctional kyphosis, stenosis, antelisthesis of the C5 vertebra and compressive ischemic cervical myelopathy in the C5–C6 segment.Material and Methods. When treating a 56-year-old patient with multiple anomalies of the craniovertebral region, differentiated surgical technologies were consistently used due to the development of late complications. The sequence and rationale for surgical decision making is described.Results. Initially, the patient underwent transoral decompression and posterior occipitocervical fixation, and after 8 years - reinstallation of the system with distal extension of the instrumentation zone to the C7 vertebra with indirect posterior decompression of the spinal cord, anterior discectomy with direct decompression and cage fixation at the C5–C6 level. Regression of myelopathic syndrome, correction of orthopedic status and significant improvement in functional status were achieved.Conclusion. A rare clinical observation demonstrates a combination of basilar invagination with assimilation of the atlas, which has provided rationale for two-stage surgical treatment in one surgical session (1st stage – transoral resection of the dens and 2/3 of the C2 vertebral body with anterior decompression of the spinal cord, and 2nd stage – occipitocervical fixation). The use of extended systems in this case caused the development of a clinically significant syndrome of the distal adjacent level, which required repeated surgical treatment after 8 years.

Assessment of mandibular trabecular structure and cervical vertebral maturation using fractal analysis.

Changes in bone trabeculae occur during skeletal maturation. Fractal analysis is a technique for assessing changes in the internal structure of the bone. The aim of this study was to investigate correlation of bone trabeculation measured on panoramic and lateral cephalometric radiographs with cervical vertebral maturation stages (CVMS). CVMS was evaluated on lateral cephalometric radiographs of 120 individuals aged 6 to 18 years. The subjects were divided into 6 groups (n= 20 each) according to CVMS. On panoramic and lateral cephalometric radiographs, fractal dimension (FD) analyses were performed in mandibular corpus, gonial and condylar regions and cervical vertebral bodies (C2, C3, C4). FD measurements from the mandibular corpus region bilaterally and C2-C4 vertebral bodies showed significant positive correlations with CVMS (r= 0.418, r= 0.412, r= 0.324, r= 0.304, r= 0.263, respectively). Significant differences were found in the FD values of the right/left mandibular corpus and C2 and C3 vertebrae compared to CVMS (P< 0.001, P< 0.001, P= 0.005, P= 0.019, respectively). Significant positive moderate correlations between the FD values of the right and left mandibular corpus and CVMS suggest that fractal analysis may be useful in determining skeletal maturity stage. The significant FD values obtained from the right/left mandibular corpus, and C2 and C3 vertebra indicate that the complexity of the internal trabecular structure increases with maturation.

Proposals for the delineation of neck clinical target volume for definitive Radiation therapy in patients with oral/ oropharyngeal squamous cell cancer based on lymph node distribution

Purpose/Objective(s)To establish the distribution pattern of cervical lymph node metastasis (LNM) and propose optimized clinical target volume (CTV) boundaries specific to oral/ oropharyngeal squamous cell cancer (OSCC/OPSCC). Materials/Methods531 patients with pathologically confirmed OSCC/OPSCC were enrolled from January 2013 to June 2022. Patients were stratified into two groups based on the minimal distance from the lesion's edge to the body's midline: ≤1 cm or > 1 cm. The geometric center of cervical metastatic LN was marked on a template CT. LN distribution probability maps were established. The relationships between the LN distribution and consensus guidelines were analyzed to propose modifications for CTV boundaries specific to OSCC/OPSCC. ResultsA total of 1962 positive LNs were enrolled. Compared with the > 1 cm group, the ≤ 1 cm group has following feature tendencies: male smokers, younger, median organs, large gross lesion, infiltrative growth pattern, contralateral LNM. The most frequently involved level of LNM was ipsilateral II, but ipsilateral Ib had the highest involvement rate in the > 1 cm OSCC group. In addition, tongue cancer had a higher incidence of LN extranodal extension (ENE), which mainly distributes in ipsilateral level II. The skip metastasis was prone to from level III to Vb (3.5 %) in LN(+)/ENE (-), and level Ib to VIa (3.7 %) in LN(+)/ENE (+). Accordingly, we proposed the following modifications: 1. only including lateral and posterior margin of submandibular gland within 5 mm; 2. retracting posterior boundary of level II to front edge of levator scapula muscle, and descending the upper boundary to transverse process of C2 vertebra only for OSCC; 3. including posterior third of thyroglossal muscle or anterior edge of sternocleidomastoid muscle; 4. sparing level Va in case of only level II involvement; 5. including upper area of the thyroid cartilage plate in case of level Ib LN(+)/ENE (+); 6. sparing level VIIa is considered. ConclusionThis is the first description of LN topographic spread patterns for OSCC/OPSCC. Modified CTV for prophylactic irradiation was proposed to spare the organs at risk and minimize adverse effects.