Artificial Intelligence Detection of Cervical Spine Fractures Using Convolutional Neural Network Models.

OBJECTIVE: To develop and evaluate a technique using convolutional neural networks (CNNs) for the computer-assisted diagnosis of cervical spine fractures from radiographic x-ray images. By leveraging deep learning techniques, the study might potentially lead to improved patient outcomes and clinical decision-making. METHODS: This study obtained 500 lateral radiographic cervical spine x-ray images from standard open-source dataset repositories to develop a classification model using CNNs. All the images contained diagnostic information, including normal cervical radiographic images (n=250) and fracture images of the cervical spine fracture (n=250). The model would classify whether the patient had a cervical spine fracture or not. Seventy percent of the images were training data sets used for model training, and 30% were for testing. Konstanz Information Miner (KNIME)'s graphic user interface-based programming enabled class label annotation, data preprocessing, CNNs model training, and performance evaluation. RESULTS: The performance evaluation of a model for detecting cervical spine fractures presents compelling results across various metrics. This model exhibits high sensitivity (recall) values of 0.886 for fractures and 0.957 for normal cases, indicating its proficiency in identifying true positives. Precision values of 0.954 for fractures and 0.893 for normal cases highlight the model's ability to minimize false positives. With specificity values of 0.957 for fractures and 0.886 for normal cases, the model effectively identifies true negatives. The overall accuracy of 92.14% highlights its reliability in correctly classifying cases by the area under the receiver operating characteristic curve. CONCLUSION: We successfully used deep learning models for computer-assisted diagnosis of cervical spine fractures from radiographic x-ray images. This approach can assist the radiologist in screening, detecting, and diagnosing cervical spine fractures.

The Clinical Outcomes of Cervical Spine Chordoma: A Nationwide Multicenter Retrospective Study.

OBJECTIVE: Chordoma, a rare malignant tumor originating from embryonal notochord remnants, exhibits high resistance to conventional treatments, making surgical resection imperative. However, the factors influencing prognosis specifically for cervical spine chordoma have not been clearly identified. We investigate the prognosis of cervical spine chordoma with factors influential in a nationwide multicenter retrospective study. METHODS: This study included all patients diagnosed with cervical spine chordoma at 7 tertiary referral centers from January 1998 to March 2023, excluding those with clivus and thoracic spine chordomas extending into the cervical spine. Local recurrence (LR) was identified through follow-up magnetic resonance imaging, either as reappearance in completely resected tumors or regrowth in residual tumors. The study assessed LR and overall survival, analyzing factors influencing LR and death. RESULTS: Forty-five patients with cervical spine chordoma had a mean age of 46.4 years. Over a median follow-up of 52 months, LR and distant metastasis were observed in 21 (46.7%) and 4 patients (8.9%), respectively, and 16 patients (36%) were confirmed dead. The 5-year and 10-year cumulative LR rates were 51.3% and 60%, respectively, while the 5-year and 10-year survival rates were 82% and 53%. Age was the only significant factor affecting mortality (hazard ratio, 1.04; 95% confidence interval, 1.04-1.07; p=0.015). Notably, the degree of resection and adjuvant therapy did not statistically significantly impact local tumor control and mortality. CONCLUSION: This study, the largest multicenter retrospective analysis of cervical spine chordoma in Korea, identified age as the only factor significantly affecting patient survival.

Post-operative Unilateral Visual Loss and Ophthalmoplegia following Cervical Spine Surgery in Prone Position: A Case Report.

ABSTRACT: Visual loss following a spine surgery in a prone position is a disastrous and irreversible complication. Moreover, the recommended treatment for such visual loss is lacking and the outcome is not so satisfactory. A 38-year-old gentleman developed profound right sided visual loss after an uneventful cervical spine surgery in a prone position that lasted approximately two and half hours. Immediate ophthalmic consultation was done and the case was diagnosed as right-sided central retinal artery occlusion. Despite the initiation of vasodilatation, anticoagulation, and adequate fluid infusion, satisfactory improvement was not achieved. Extensive review of pertinent literature highlighted limited efficacy of treatments for postoperative visual loss after prone spinal surgery, further emphasizing the importance of preventive measures as the cornerstone in such procedures.

Evaluation of Upper Airway Growth Patterns With Cephalometric Analysis Based on Cervical Vertebral Maturation in the Japanese: A Cross-Sectional Study.

Objective This study aims to establish standard values for the upper airway cross-sectional area and evaluate growth patterns using the cervical vertebral maturation stage (CVMS) in a Japanese population. Methods A cross-sectional sample of 400 patients, aged 6-20 years, was selected randomly from the Orthodontic Clinic at Tokyo Medical and Dental University (TMDU) dental hospital. Cervical vertebral maturation stages (CVMS I-V) guided the classification of participants into five equal groups. Lateral cephalometric radiographs taken prior to orthodontic treatment were used to measure the upper airway's cross-sectional area. The growth spurt and sex differences in growth patterns were assessed through these measurements. Results Standard values for the upper airway dimensions at each CVMS stage were established. Significant growth spurts were noted between CVMS II-III and CVMS III-IV in males and at CVMS II-III in females. The weighted kappa coefficient (κ) demonstrated almost perfect intra- and inter-evaluator agreement, confirming the reliability of CVMS in growth assessment. Conclusion CVMS provides a reliable framework for assessing growth patterns of the upper airway, with distinct variations between sexes noted. These findings support the utility of CVMS in clinical growth evaluation and orthodontic treatment planning.

Giant cell tumor of the cervical spine: A very uncommon cause for cervical spine compression.

Giant cell tumors (GCTs) are rare neoplasms, primarily found in long bones, typically affecting the epiphysis of the distal femur, proximal tibia, and distal radius. However, their occurrence in the cervical spine is exceedingly rare. Here, we present a case report of a 21-year-old female patient who presented with progressive neck pain, radiating numbness, and right hemiparesis. Radiographic imaging revealed a lytic lesion in the C3 vertebral body, further characterized by magnetic resonance imaging (MRI) and computed tomography (CT) scans. The patient underwent surgery for stabilization of the cervico-occipital hinge, decompression, and biopsy. Histopathological examination confirmed the diagnosis of a giant cell tumor. Postoperatively, the patient showed improvement in motor impairment, cervical pain, and numbness. She was proposed for adjuvant treatment based on Denosumab. However, she returned 1 month after surgery with worsened motor deficit, developing tetraparesis. Control MRI revealed a tumor flare-up. The decision was made not to reoperate on the patient and to accelerate the administration of Denosumab. Meanwhile, she experienced a pulmonary embolism leading to her demise. This case underscores the importance of considering giant cell tumors in the differential diagnosis of cervical spine lesions and emphasizes the successful and prompt management through a multidisciplinary approach involving surgical intervention and adjuvant therapy.

Correlation Between Radiological Changes of the Temporomandibular Joint and Upper Cervical Vertebrae in Degenerative Joint Disease: A Cone-Beam Computed Tomography-Based Analytical Study.

Objectives This study was conducted to assess the radiological changes of the temporomandibular joint (TMJ) and cervical vertebrae individually and their correlation in degenerative joint disease (DJD) using a cone-beam computed tomography (CBCT)-based approach. Methodology The study employed a cross-sectional, analytical retrospective design, analyzing one-year data. CBCT scans of 60 patients (120 TMJs) were assessed for degenerative changes using standardized imaging parameters. Eligibility criteria included full field-of-view CBCT scans, excluding those with craniofacial anomalies or prior orthodontic treatment. Radiological assessments of TMJs and cervical vertebrae were conducted by experienced radiologists using the Anjos Pontual method and novel grading system (TMJ Spine Degenerative Severity Index). Results The study included 60 CBCT scans (120 joints), with 31.7% males and 68.3% females. Participants were predominantly aged 31-60 years (58.3%). DJD findings for the right TMJ showed grade 1 changes in 55.0% and grade 2 in 31.7%, while the left TMJ had 46.7% grade 1 and 35.0% grade 2 changes. A strong positive correlation (0.704) was found between bilateral TMJ and cervical vertebrae changes. Age correlated significantly with TMJ alterations but not with cervical vertebrae changes. Conclusion This study demonstrated that there exists a positive association between the radiological changes of TMJ and cervical vertebrae in DJD with age, which can be detected in mild stage of severity on CBCT and can be of use in clinical correlation and application of optimal interventions ensuring better prognosis.

Successful Non-operative Management of Unstable Jefferson Fracture With Transverse Atlantal Ligament Injury (Dickman Type I and IIb) in a Pediatric Patient: A Case Report.

This report presents the case of a Jefferson fracture (posterior arch fracture) associated with an unstable avulsion fracture and substance injury of the transverse atlantal ligament (Dickman type I and IIb) in an eight-year-old male child. The patient was managed conservatively with external immobilization using a halo vest and a sternal occipital mandibular immobilizer (SOMI) brace and subsequently made a full recovery. Computed tomography (CT) and dynamic cervical spine radiographs at the final follow-up demonstrated solid reattachment of the avulsed bony fragment of the transverse atlantal ligament and no instability at the C1/2 level. This case report adds to the literature on the optimal non-operative management of the rare pediatric unstable C1-C2 trauma.

Craniovertebral Junction Deformity Diagnosed by Computed Tomography: A Case Report.

Craniovertebral junction (CVJ) deformities, including basilar invagination and atlanto-occipital assimilation, present significant challenges in diagnosis and management due to their complex nature and impact on neurological function. We report a case of a 28-year-old female who experienced neck pain, weakness, tingling in the upper limbs, restricted neck movements, occipital headaches, and intermittent dizziness. These symptoms progressively worsened over six months, markedly affecting her quality of life. Neurological examination revealed reduced motor power in the upper limbs and a diminished bicipital tendon reflex, while other assessments remained normal. Cervical spine CT imaging was done which revealed basilar invagination and atlanto-occipital assimilation. This case underscores the importance of recognizing and managing CVJ deformities, highlighting the need for a multidisciplinary approach to address anatomical and associated neurological symptoms. Early and accurate diagnosis and a tailored treatment strategy are crucial for improving patient outcomes.

Early Occipitocervical Fusion Surgery in a Rare Clinical Encounter of Non-traumatic Atlantooccipital Subluxation (AOS) in Down Syndrome (Trisomy 21).

Subluxation of the atlantooccipital joint in patients with underlying Down syndrome is an extremely rare orthopedic condition. The condition can pose life-threatening risks if not promptly diagnosed and treated in the early stage. Yet, there have been documented cases of survival following atlantooccipital subluxation or dislocation. Atlantooccipital subluxation (AOS) is usually identified during screening in children with Down syndrome for atlantoaxial subluxation (AAS). Therefore, careful evaluation of the atlantooccipital joint from radiographs is also essential. It is crucial to emphasize the clinical significance of AOS. Here the authors present the case of a fifteen-year-old girl with underlying Down syndrome (trisomy 21) who survived a sudden onset of non-traumatic atlantooccipital subluxation with spinal cord compression. There are only a few cases were reported in patients with Down syndrome (trisomy 21) and only two cases with surgically treated atlantooccipital (C0C1) subluxation have been reported. This case is of particular interest as it represents the first reported case of atlantooccipital (C0C1) subluxation with spinal cord compression in Down syndrome that underwent occipitocervical fusion surgery during the acute presentation, resulting in significant neurological recovery. Her neurology symptoms and physical functions showed remarkable improvement post-surgery, and she is doing well at the one-year follow-up in the clinic. Early surgery during acute presentation in this case resulted in good surgical outcomes and improved patient quality of life.

Pediatric C-spine Clearance by CT: A Retrospective Cohort Study.

BACKGROUND: Pediatric cervical spinal injury (CSI) remains a significant concern following blunt trauma, with mortality rates as high as 48%. Current protocols involve cervical immobilization and clearance through multidetector computed tomography (MDCT) scans, followed by magnetic resonance imaging (MRI) or clinical examination. However, prolonged collar use poses risks, necessitating timely clearance. This study assessed the efficacy of MDCT in pediatric CSI clearance. METHODS: A retrospective cohort study, spanning January 2019 to January 2023, included pediatric patients under 18 undergoing cervical CT scans. RESULTS: MDCT sensitivity was evaluated, with 13.8% positive scans, detecting clinically significant injuries. MRI identified no additional injuries, affirming MDCT reliability. The average clearance time was 24.9 hours, impacting hospitalization durations. Mortality unrelated to CSI was excluded. CONCLUSION: These results align with recent studies advocating cervical collar removal based on negative MDCT, emphasizing its potential to decrease the time that patients remain in C-collars and expedite hospital courses, including therapy and discharge. The study encourages consideration of MDCT-based protocols for timely pediatric CSI clearance, promoting patient care efficiency and informed medical decision-making.

Evaluating laminar and lateral mass screw techniques in cervical injury management: A case series.

INTRODUCTION AND IMPORTANCE: The cervical spine is a dynamic structure that protects adjacent nervous innervation and maintains the range of motion (ROM) of the head and neck. Fractures in this area can lead to high mortality and morbidity, with bone fractures accounting for 56 % of cervical spinal cord injuries. This case series presents a series of cervical pathologies treated with posterior decompression and stabilization using laminar and lateral mass screw fixation. METHODS: This research is a case series of four patients treated with laminar and lateral mass screw technique. All patients received a surgical procedure, including posterior compression and stabilization, which included the use of a laminar and lateral mass screw. We followed the patient for 12 months. During follow up, outcome measures consisting of VAS, range of motion, neurological status, ODI Score, SF-12 Score and any complications related to the surgical procedure was recorded and calculated every 3 months. OUTCOMES: This series examines four distinct cases. The initial case pertained to a female patient, aged 72, who exhibited tetraparesis resulting from a burst fracture occurring in the C3-C5 vertebrae. The underlying etiology of this pathology is considered to be mineral bone disease associated with thyroid hormone imbalance due to thyroid cancer. The second instance was a 14-year-old child experiencing neck pain due to spondylitis tuberculosis in the C1-C2 region, accompanied by a retropharyngeal abscess and occipitocervical dissociation (OCD) with basilar invagination. The third example pertained to a patient who is 9 years old and presented with weakness in all extremities due to C1 fracture-dislocation. The fourth case was a 14-year-old patient who experienced a fall from a bunk bed. This patient was diagnosed with Traumatic Atlantoaxial dislocation with odontoid fracture Type II. All patients showed improved cervical curvature and range of motion with the advantages of reduction of intraoperative haemorrhage, as well as a decrease in postoperative rehabilitation duration. Overall, the data shows a general trend of improvement in VAS and ODI scores over time, with SF-12 scores stabilizing or slightly decreasing by 12 months post-operation. CONCLUSION: The use of a lateral mass screw for subaxial cervical injuries can be employed to manage cervical spine pathologies like fractures and infections, including spondylitis TB. However, more research is required to evaluate the long-term complications and success rates of this technique.

Novel MRI signs of the atlantodental space in patients with atlantoaxial dislocation.

OBJECTIVES: The type of atlantodental space tissue in patients with atlantoaxial dislocation (AAD) can help doctors understand the possibility of reduction before surgery. However, relevant research on this topic is lacking. In this study, we aimed to summarise the atlantodental space classification of patients with AAD using magnetic resonance imaging (MRI) and explore their clinical characteristics. MATERIALS AND METHODS: Preoperative 3T cervical MR images of patients who underwent posterior reduction and fixation surgery for non-traumatic AAD between 1 September 2012 and 31 July 2023 were collected. Two radiologists read and recorded the MRI results based on the standard protocol. The kappa value was used to evaluate intra- and inter-observer agreements. The patient's age, sex, body mass index, clinical symptoms, Japanese Orthopaedic Association (JOA) score, and visual analogue scale information were obtained from medical records. RESULTS: A total of 135 patients with AAD (mean age, 51.3 ± 14.0 years, 52 men) were included in the analysis. The inter-observer agreement between the two readers was 0.818 (P < 0.0001). The intra-observer consistencies were 0.882 (P < 0.0001) and 0.896 (P < 0.0001). Patients with inflexible tissue signs exhibit more irreducible in hyperextension position, and their range of motion of ADI is smaller. These patients were older and had a higher incidence of abnormal spinal cord signals and JOA scores. CONCLUSIONS: Novel MRI signs exhibited high inter- and intra-observer consistency and were associated with patient age, abnormal spinal cord signals, reducibility, range of motion of ADI, and symptoms.

Reliability of a Musculoskeletal Assessment for the Examination of Cervical Spine Pain and Injuries in Special Forces Combat Soldiers.

An assessment of protocol reliability is an essential step prior to human subject testing for injury prevention. The purpose of this study was to examine the inter-rater and intra-rater reliability of a portable cervical range of motion and isometric strength protocol designed for special forces combat soldiers who are at risk for cervical spine pain and injury due to exposure to head-supported mass. Eight individuals were tested three times to assess reliability, the standard error of the measurement (SEM), and the minimal detectable change across six range of motion measures and six strength measures of the cervical spine. One tester tested all participants twice for intra-rater reliability, and a second tester assessed the participants to examine inter-tester reliability. All reliability measures demonstrated good to excellent reliability (ICC = 0.70-0.96 (isometric strength); ICC = 0.85-0.94 (range of motion)). All SEM scores were 12% or lower for all reliability measures. The findings of this study demonstrate that the protocol developed for a longitudinal multi-site study is reliable and appropriate to implement for injury prevention in military personnel.

Cervical spine spondylodiscitis due to neglected esophageal perforation after a dilation procedure 30 years after a laringectomy and radiotherapy. Report of a case and review of literature.

Current treatment of cervical spine spondylodiscitis generally involves a radical surgical debridement and stable reconstruction together with antibiotic therapy until complete healing. But this classical approach could be difficult for patients who have been treated previously for an esophageal carcinoma and received radiotherapy. We present a case of a 75-year-old male who underwent an esophageal dilation procedure and developed afterward a spondylodiscitis with epidural abscess due to a neglected esophageal perforation. Blood cultures were positive for Peptostreptococcus. Cervical spondylodiscitis and epidural abscess are extremely rare complications of esophageal dilations. Successful treatment without debridement was achieved by performing a posterior fixation without decompression associated with antibiotic therapy for 8 weeks. The present case highlights that spondylodiscitis and epidural abscess may be treated in selected cases where the anterior neck is unapproachable and with a recognized pathogen by a posterior approach fixation without debridement, in association to specific antibiotic therapy.

Transcranial Corticospinal Motor-Evoked Potentials in Cases of Ventral and Ventrolateral Intradural Extramedullary Cervical Spinal Cord Tumors.

Background and Objectives: We studied the clinical significance of an amplitude decrement and disappearance alarm criteria in transcranial motor-evoked potential (MEP) monitoring during surgeries on extramedullary tumors at the cervical spine with reference to postoperative morbidity. Material and Methods: We diagnosed and surgically treated fourteen patients with intradural extramedullary ventral or ventrolateral lesions to the cervical spinal cord in the Clinic of Neurosurgery at the University Hospital St Ivan Rilski from January 2018 to July 2022. Eight cases were diagnosed with schwannoma, and the remaining six had meningiomas. The follow-up period for neurological assessment was six months. Results: A decrease in the intraoperative transcranial MEPs of 50% or more compared to baseline in two cases (14.3%) resulted in an immediate postoperative motor deficit. One patient demonstrated full neurological recovery within six months, while the other exhibited only partial improvement. In six cases (42.9%) with preoperative motor deficits, tumor resection and decompression of the cervical spinal cord led directly to an increment of the transcranial MEPs by more than 20%. Postoperatively and at the 6-month follow-up, these patients showed recovery from the preoperative deficits. In the remaining cases, MEPs were stable during surgery with no clinical deterioration of the motor function. Conclusions: The decremented MEP criteria corresponded to postoperative motor deficit, whereas the improvement of the same parameters after decompression implied future recovery of preoperative motor deficits. The combination of different MEP criteria is likely to be helpful when tailored to a specific case of ventral or ventrolateral extramedullary lesions in the cervical spine.

Rehabilitation to Improve Outcomes after Cervical Spine Surgery: Narrative Review.

PURPOSE: The increasing elderly patient population is contributing to the rising worldwide load of cervical spinal disorders, which is expected to result in a global increase in the number of surgical procedures in the foreseeable future. Cervical rehabilitation plays a crucial role in optimal recovery after cervical spine surgeries. Nevertheless, there is no agreement in the existing research regarding the most suitable postsurgical rehabilitation program. Consequently, this review assesses the ideal rehabilitation approach for adult patients following cervical spine operations. MATERIALS AND METHODS: This review covers activities of daily living and encompasses diverse treatment methods, including physiotherapy, specialized tools, and guidance for everyday activities. The review is organized under three headings: (1) historical perspectives, (2) patient-reported functional outcomes, and (3) general and disease-specific rehabilitation. RESULTS: Rehabilitation programs are determined on the basis of patient-reported outcomes, performance tests, and disease prognosis. CSM requires strengthening of the neck and shoulder muscles that have been surgically invaded. In contrast, the CCI requires mobility according to the severity of the spinal cord injury and functional prognosis. The goal of rehabilitation for CCTs, as for CCIs, is to achieve ambulation, but the prognosis and impact of cancer treatment must be considered. CONCLUSIONS: Rehabilitation of the cervical spine after surgery is essential for improving physical function and the ability to perform daily activities and enhancing overall quality of life. The rehabilitation process should encompass general as well as disease-specific exercises. While current rehabilitation protocols heavily focus on strengthening muscles, they often neglect the crucial aspect of spinal balance. Therefore, giving equal attention to muscle reinforcement and the enhancement of spinal balance following surgery on the cervical spine is vital.

Influence of Sagittal Cervical and Thoracic Range of Motion on Neck Pain Severity in Young White-Collar Workers: A Cross-Sectional Study.

Background: Neck pain (NP) is a prevalent musculoskeletal disorder, especially among individuals with sedentary occupations. The interplay between cervical and thoracic spine mobility is hypothesized to contribute significantly to NP severity, yet this relationship requires further exploration. Methods: This cross-sectional study involved 179 young white-collar workers with NP lasting for at least six weeks. Participants were stratified into mild (n = 78) and moderate (n = 101) pain groups based on their scores on the Northwick Park Neck Pain Questionnaire (NPQ). Cervical and thoracic range of motion (ROM) in the sagittal plane was measured using inclinometers. NP severity was further assessed using the NPQ and the Neck Disability Index (NDI). Correlation, regression, and mediation analyses were conducted to investigate the relationship between cervical and thoracic ROM and NP severity. Results: Thoracic ROM was higher in the mild pain group (median: 47.35, IQR: 10.13) than in the moderate pain group (median: 42.10, IQR: 13.60; p < 0.001). The NDI had a negative correlation with thoracic ROM (r = -0.65; p < 0.05) and a positive correlation with cervical ROM (r = 0.84; p < 0.01). Additionally, thoracic ROM mediated the effect of cervical ROM on NP, particularly influencing NDI scores (p < 0.01). Conclusions: This study found a significant association between reduced thoracic ROM and increased NP severity, highlighting the role of thoracic spine mobility in NP among young white-collar workers. Targeted interventions for thoracic dysfunction may reduce compensatory cervical strain and improve NP management, suggesting that thoracic spine assessments should be integrated into routine clinical evaluations.

Dosimetric Comparison between the HyperArc and Conventional VMAT in Cervical Spine Stereotactic Radiosurgery.

Background: This research aims to evaluate the usability of the HyperArc (HA) technique in stereotactic radiosurgery for cervical spine metastasis by comparing the dosimetry of the target and organs at risk, specifically the spinal cord, between HA and VMAT and conventional volumetric modulated arc therapy (VMAT). Methods: A RANDO® phantom and QFix EncompassTM and support system were used to simulate three target types (A, B, and C) based on RTOG0631 guidelines. Treatment plans included one VMAT and two HyperArc techniques with different SRS NTO values (100 and 250). Dosimetric parameters such as conformity index (CI), homogeneity index (HI), R50, and spinal cord sparing were analyzed. Gamma analysis was performed using portal dosimetry to validate the dose delivery accuracy. Results: HyperArc plans demonstrated higher conformity, sharper dose fall-off, and improved quality assurance (QA) results compared to VMAT plans. HA with SRS NTO 250 showed even better results in terms of conformity, dose fall-off, and spinal cord dose reduction (V10 and Dmax) compared to HA with SRS NTO 100. Although the mean gamma passing rates were slightly lower, all plans achieved rates above 95%. Conclusion: The findings suggest that HA provides superior dosimetric benefits over VMAT and could be effectively utilized for cervical spine radiation therapy.

[Transport of severely injured trauma patients in an ambulance with and without a rigid neck orthosis: comparative biomechanical measurements]. / Transport von schwer verletzten Traumapatienten im Rettungswagen mit und ohne starre Halsorthese: vergleichende biomechanische Messungen.

BACKGROUND: The actual significance of prehospital immobilization of the cervical spine in severely injured trauma patients remains unclear. In view of possible negative implications, such as an increase in intracranial pressure due to the application of a rigid cervical spine orthosis, the long-term use must be critically questioned. Further studies are required to justify the long-term use of a rigid cervical spine orthosis in the prehospital setting. OBJECTIVE: Comparative measurements of the mobility of the cervical spine during immobilization using a vacuum mattress with or without the additional application of a rigid cervical spine orthosis after positioning on the stretcher were carried out. MATERIAL AND METHODS: Biomechanical measurements of the movement of the cervical spine were carried out by attaching inertial measurement units to a test person during the loading and unloading process in a modern ambulance and during the journey along a predefined parkour. The test person on whom the measurements were carried out was immobilized on a vacuum mattress with the option of lateral fixation of the head and chin and forehead strap on an electrohydraulic stretcher. The complete standard monitoring was set up to simulate as realistic a transport of a severely injured patient as possible. A total of 30 test runs were realized. In one half of the tests, the cervical spine was additionally immobilized using a rigid orthosis and in the other half a cervical spine orthosis was not used. For each of the 30 tests, the angles, axial rotation, lateral bending and flexion/extension as well as the first and second derivatives were considered for loading, transport and unloading and the parameters mean deviation from the zero position, size of the swept angle range and maximum were calculated for each test run. RESULTS: Statistically significant differences were only found for some biomechanical parameters in the sagittal plane (flexion and extension). No significant differences were found for the measured parameters in the other directions of movement (axial rotation, lateral flexion). In general, only very small angular deflections were measured both in the tests with the cervical spine orthosis and without the cervical spine orthosis (on average in the range of 1-2° for axial rotation and flexion/extension and up to 3° for lateral flexion). CONCLUSION: If immobilization is carried out correctly using a vacuum mattress with the option of lateral stabilization of the head and chin and a forehead strap on an electrohydraulic stretcher with a loading system, there are no relevant advantages with respect to the restriction of movement of the cervical spine by the additional use of a rigid cervical spine orthosis for the loading and unloading process or during the transport in a modern ambulance. It could therefore be advantageous to remove the rigid cervical spine orthosis initially applied for the rescue of the patient at the scene after the patient has been positioned on the vacuum mattress and stretcher to avoid potential negative effects of the rigid cervical spine orthosis for the period of transportation to the hospital.

Anatomical Relationships of Internal Carotid Artery with Posterior Pharyngeal Wall and Upper Cervical Spine: Analysis of 238 Computed Tomography Angiograms.

OBJECTIVE: To evaluate internal carotid artery's (ICA) anatomical relationships with atlantoaxial joints and posterior pharyngeal wall and to illustrate ICA injury risk during transoral procedures to upper cervical spine. METHODS: Cervical spine computed tomography angiography (CTA) of 238 patients were retrospectively evaluated. Each ICA was classified into one of three zones: areas medial (Zone 1), anterior (Zone 2), or lateral (Zone 3) to the atlantoaxial joint. For an ICA in Zone 1, the shortest distances to the posterior pharyngeal wall and midsagittal plane were measured. For an ICA in Zone 2, the closest distances to the midsagittal plane and anterior cortex of the C1-2 complex were measured. RESULTS: Fifteen ICAs in Zone 1 were found in 12 (5%) patients, with three female patients having bilateral ICAs medial to the atlantoaxial joint. The incidence of ICA in Zone 1 was higher in females than in males. In cases of ICAs in Zone 2, the ICAs were close to the anterior cortex of C1-2 complex, with the shortest distance being 2.6±1.5 mm. A total of 39.9% of patients had bilateral ICAs in Zone 3. CONCLUSION: Transoral surgeries in the upper cervical spine carry potential ICA injury risk. They should be carefully deliberated in patients whose ICAs are in Zone 1. In cases of ICAs in Zone 2, meticulous subperiosteal stripping and gentle traction should be performed on the posterior pharyngeal wall. Preoperative identification of the course of ICAs is mandatory in patients undergoing transoral surgeries in the upper cervical spine.