3D-printed neck phantoms with detailed anatomy for ultrasound-guided procedure and device testing.

Objectives: With rapid advances in ultrasound-guided procedures, there is an unmet need for echogenic phantoms with sufficient anatomical details for artificial intelligence and ultrasound-guided device testing. We developed a method for creating neck phantoms for novel otolaryngology-related device testing. To achieve accurate representation of the anatomy, we utilized CT scans and 3D printing technology to create customized agar molds, thus providing high-fidelity yet cost-effective tools. Methods: Based on previous studies, the key components in our neck phantom include the cervical vertebrae, trachea, common carotid arteries, internal jugular veins, thyroid gland, and surrounding soft tissue. Open-source image analysis software were employed to process CT data to generate high fidelity 3D models of the target structures. Resin molds were 3D printed and filled with various agar mixtures to mimic anatomical echogenicity. Results: Following the method proposed, we successfully assembled the neck phantom which provided a detailed representation of the target structures. To evaluate the results, ultrasound data was collected on the phantom and living tissue and analyzed with ImageJ. We were able to demonstrate echogenicity comparable to that of living tissue. Conclusion: The proposed method for building neck phantoms with detailed anatomical features offers a valuable, detailed, low-cost tool for medical training and device testing in otolaryngology, particularly for novel devices that involve artificial intelligence (AI) guidance and robotic-based needle insertion. Additional anatomical refinements and validation studies could further enhance the consistency and accuracy, thus paving the way for future advancements in ultrasound training and research, and ultimately benefiting patient care and safety.

Exploring the atlantic part of the vertebral artery in the South Indian Population and its implications in spine surgery.

Study Design: A descriptive, quantitative cross-sectional study of the atlantic part (V3) of the vertebral artery (VA). Purpose: This study aimed to bridge the research gap in the morphometry of the V3 segment of the VA in the South Indian population. Overview of Literature: The microsurgical anatomy of this segment of the VA has been explored in various populations, and a thorough understanding of the anatomy and course of the VA, particularly the V3 segment, is essential to prevent iatrogenic complications. Several computed tomography studies but a few cadaveric studies have explored the V3 segment of the VA in the South Indian population. Methods: This study examined 40 VAs from 20 embalmed cadavers that were obtained from the voluntary donation program, and Institutional Ethical Clearance was obtained before the study. The length, diameter, and angle of the vertical, horizontal, and exit parts of the V3 segment of the VA were documented after its exposure. Results: The mean lengths of the right and left VAs on each part were nearly similar, except for the mean length of the horizontal part (right: 38.937 mm, left: 40.237 mm) and total length of the V3 segment (right: 66.870 mm, left: 70.350 mm). Conclusions: These morphometric parameters are essential to spine surgeons who intend to operate on a small part (vertical, horizontal, or exit part) of the V3 segment of the VA. The mean values of the parameters obtained in this study give average measurements or safe limits to surgeons for safe surgical procedures such as the occipital condyle screw technique and C1 laminectomy.

A machine learning-based approach for individualized prediction of short-term outcomes after anterior cervical corpectomy.

Study Design: A retrospective machine learning (ML) classification study for prognostic modeling after anterior cervical corpectomy (ACC). Purpose: To evaluate the effectiveness of ML in predicting ACC outcomes and develop an accessible, user-friendly tool for this purpose. Overview of Literature: Based on our literature review, no study has examined the capability of ML algorithms to predict major shortterm ACC outcomes, such as prolonged length of hospital stay (LOS), non-home discharge, and major complications. Methods: The American College of Surgeons' National Surgical Quality Improvement Program database was used to identify patients who underwent ACC. Prolonged LOS, non-home discharges, and major complications were assessed as the outcomes of interest. ML models were developed with the TabPFN algorithm and integrated into an open-access website to predict these outcomes. Results: The models for predicting prolonged LOS, non-home discharges, and major complications demonstrated mean areas under the receiver operating characteristic curve (AUROC) of 0.802, 0.816, and 0.702, respectively. These findings highlight the discriminatory capacities of the models: fair (AUROC >0.7) for differentiating patients with major complications from those without, and good (AUROC >0.8) for distinguishing between those with and without prolonged LOS and non-home discharges. According to the SHapley Additive Explanations analysis, single- versus multiple-level surgery, age, body mass index, preoperative hematocrit, and American Society of Anesthesiologists physical status repetitively emerged as the most important variables for each outcome. Conclusions: This study has considerably enhanced the prediction of postoperative results after ACC surgery by implementing advanced ML techniques. A major contribution is the creation of an accessible web application, highlighting the practical value of the developed models. Our findings imply that ML can serve as an invaluable supplementary tool to stratify patient risk for this procedure and can predict diverse postoperative adverse outcomes.

Does hydrogen peroxide help mitigate the incidence of Cutibacterium acnes in cervical spine surgeries?

Background: Surgical site infection (SSI) is a common yet serious complication of cervical spine surgery. While initially thought to be clinically insignificant, Cutibacterium acnes (C. acnes) is an important cause of infection. The purpose of this study was to investigate the ability of a hydrogen peroxide (H2O2) application during standard presurgical skin preparation to reduce the burden of C. acnes in patients undergoing cervical spine surgery. Methods: This was a retrospective review of prospectively collected data. Subjects were randomly assigned to either standard surgical preparation plus H2O2 (experimental) or without H2O2 (control). Prescrub, postscrub, and dermal cultures were obtained to assess the C. acnes burden after cultures on an aerobic and anaerobic growth medium were held for 21 days. Multivariate analysis was conducted to determine factors associated with presence of C. acnes. Outcome measures included the results of intraoperative cultures and the development of a SSI within 90 days postoperatively. Results: Patients (n=86) undergoing elective 2- or 3-level fusion via anterior approach were included. Prior to application of the antiseptic solution, 65% (28/43) of the experimental cohort and 77% (33/43) of the control cohort had positive C. acnes cultures (p=.34). Following application of antiseptic solution, there were no differences in positive C. acnes culture rates between the experimental and control cohorts in the epidermal (30% vs. 28%, p=1.00) or dermal (40% vs. 42%, p=1.00) cultures. No differences in the rates of C. acnes eradication from preantiseptic to postantiseptic application occurred for epidermal (p=1.00) or dermal (p=1.00) skin layers. None of the factors were associated with positive C. acnes epidermal cultures on multivariable logistic regression analysis (p>.05). Conclusions: While there is potential for H2O2 to reduce the positive culture rate of C. acnes in cervical spine patients, no difference was seen when compared to standard surgical skin preparation.

Correlations of spheno-occipital synchondrosis, cervical vertebrae, midpalatal suture, and third molar maturation stages.

OBJECTIVES: To estimate the joint correlations among cervical vertebrae maturation (CVM), spheno-occipital synchondrosis (SOS), midpalatal suture maturation (MPS), and third molar mineralization (TMM) and to assess the predictive potential of SOS on CVM and MPS. MATERIALS AND METHODS: 570 pretreatment cone-beam computed tomogram (CBCT) scans from three private practices were analyzed, and MPS, CVM, SOS, and TMM stages were categorized and recorded by two independent investigators. Intra- and inter-rater reliability tests were evaluated with weighted Cohen's kappa tests. Spearman correlation coefficients for ordinal data were used to estimate the pairwise correlations among SOS, CVM, MPS, and TMM. To evaluate if SOS could predict CVM and MPS, ordinal regression models were estimated and cross-validated. RESULTS: The analysis demonstrated a robust positive correlation between SOS and CVM (r = 0.845) and between SOS and MPS (r = 0.742). A significant correlation was also observed between CVM and MPS (r = 0.659). Further correlations were identified between TMM and SOS (r = 0.444), TMM and MPS (r = 0.392), and TMM and CVM (r = 0.358). Ordinal regression models indicated the potential of using SOS as a predictive marker for CVM and MPS stages. CONCLUSIONS: With a comprehensive analysis, SOS is strongly correlated with CVM and MPS, and SOS stage can be used to predict CVM and MPS using ordinal regression. Since MPS stages are challenging to categorize due to their anatomy, this finding suggests a diagnostic tool using SOS stages or when more information on skeletal maturity of the patient is desired.

Comparative analysis of contrast distribution in cervical epidural steroid injections utilizing a modified paramedian interlaminar approach with varied needle tip positions: A randomized controlled trial.

BACKGROUND: Recent advancements in cervical interlaminar epidural steroid injections have given rise to the modified paramedian interlaminar (mPIL) approach. The objective of this study was to perform an analysis of the contrast spread pattern within the cervical epidural space, taking into account different needle tip positions in the mPIL approach. METHODS: A total of 48 patients were included in the study and randomly assigned to either the medial or lateral group based on the needle tip's position in the anterior-posterior view. The primary outcome measured was the contrast flow under fluoroscopic visualization. As a secondary outcome, we analyzed the location of the needle tip position in both lateral and contralateral oblique views. Clinical effectiveness was assessed by measuring pain intensity and functional disability post-procedure. RESULTS: Significant disparities were noted in the ventral distribution of contrast between the medial and lateral groups. In the lateral images, needle tips in the lateral group were positioned more ventrally compared to those in the medial group. Both groups exhibited statistically significant improvements in neck and radicular pain, as well as functional status, 4 weeks after treatment, with no significant differences between them. CONCLUSIONS: Our results suggest that the ventral dispersion of contrast material during cervical interlaminar epidural steroid injections using the mPIL approach may vary depending on the needle tip location.

Clinical and Radiological Outcomes in C2 Recapping Laminoplasty for the Pathologies in the Upper Cervical Spine.

OBJECTIVE: To evaluate C2 muscle preservation effect and the radiological and clinical outcomes after C2 recapping laminoplasty. METHODS: Fourteen consecutive patients who underwent C2 recapping laminoplasty around C1-2 level were enrolled. To evaluate muscle preservation effect, the authors conducted a morphological measurement of extensor muscles between the operated and nonoperated side. Two surgeons measured the cross-sectional area (CSA) of obliquus capitis inferior (OCI) and semispinalis cervicis (SSC) muscle before and after surgery to determine atrophy rates (ARs). Additionally, we examined range of motion (ROM), sagittal vertical axis (SVA), neck visual analogue scale (VAS), Neck Disability Index (NDI), and Japanese Orthopaedic Association (JOA) score to assess potential changes in alignment and consequent clinical outcomes following posterior cervical surgery. RESULTS: We measured the CSA of OCI and SSC before surgery, and at 6 and 12 months postoperatively. Based on these measurements, the AR of the nonoperated SSC was 0.1% ± 8.5%, the AR of the operated OCI was 2.0% ± 7.2%, and the AR of the nonoperated OCI was -0.7% ± 5.1% at the 12 months after surgery. However, the AR of the operated side's SSC was 11.2% ± 12.5%, which is a relatively higher value than other measurements. Despite the atrophic change of SSC on the operated side, there were no prominent changes observed in SVA, C0-2 ROM, and C2-7 ROM between preoperative and 12 months postoperative measurements, which were 11.8 ± 10.9 mm, 16.3° ± 5.9°, and 48.7° ± 7.7° preoperatively, and 14.1 ± 11.6 mm, 16.1° ± 7.2°, and 44.0° ± 10.3° at 12 months postoperative, respectively. Improvement was also noted in VAS, NDI, and JOA scores after surgery with JOA recovery rate of 77.3% ± 29.6%. CONCLUSION: C2 recapping laminoplasty could be a useful tool for addressing pathologies around the upper cervical spine, potentially mitigating muscle atrophy and reducing postoperative neck pain, while maintaining sagittal alignment and ROM.

Current practices of cervical epidural block for cervical radicular pain: a multicenter survey conducted by the Korean Pain Society.

Background: Cervical epidural block (CEB) is an effective intervention for managing cervical radicular pain. This study aimed to investigate the current status of performing CEB in South Korea. Methods: Pain physicians affiliated with the Korean Pain Society were asked to complete anonymous questionnaires regarding CEB between September and October 2022. The questionnaire consisted of 24 questions assessing the current status and methods of CEB in detail. Results: Of the 198 surveys collected, 171 physicians (86.4%) reported performing CEB. Among those, the majority (94.7%) used fluoroscopy during the procedure. The paramedian interlaminar (IL) approach was the most preferred method (50.3%). Respondents performing fluoroscopic-guided IL CEB were categorized into two groups based on clinical experience: those with ≤10 years of experience (≤10-year group, n = 91) and those with >10 years of experience (>10-year group, n = 71). The proportion of physicians obtaining informed consent in the ≤10-year group and >10-year group was 50.5% and 56.3%, respectively. When entering the epidural space during IL CEB, the contralateral oblique view was the second most frequently used in both groups (≤10-year group, 42.9%; >10-year group, 29.6%). In targeting the upper cervical lesions (C3-4), the proportion of respondents who used an IL space higher than C6-7 was 17.6% in the ≤10-year group and 29.5% in the >10-year experience group. Conclusions: This study demonstrated variability in the CEB technique used by pain physicians in South Korea. The findings highlight the need for education on informed consent and techniques to enhance safety.

Changes in lateral standing posture following orthognathic surgery: a cohort study.

Altering neuromuscular and musculoskeletal relationships also affects standing body posture, particularly in the head and neck areas. This prospective cohort study assessed the effects of orthognathic surgery on head posture in the lateral standing view. Thirty-one patients who underwent single-jaw orthognathic mandibular surgery were included. The patients underwent cephalometric and photographic evaluations of their habitual posture before and 6 months after surgery. The craniovertebral angle and Frankfort angle were determined and measured using MB-Ruler software. Mandibular positional changes were also measured by superimposing lateral cephalograms and recording changes in the menton point. All data were analysed by paired t-test. The craniovertebral angle increased significantly in patients with Class II malocclusion (P = 0.001) and decreased significantly in Class III patients (P = 0.004). Furthermore, the Frankfort angle was significantly increased in both Class II (P = 0.005) and Class III (P = 0.012) patients. The tendency towards forward head posture decreased in Class II patients, and the neck posture improved. Conversely, a slight but significant tendency towards a forward head posture was observed in Class III patients after surgery. Furthermore, the natural head position changed in both study groups, leading to a more upright head posture.

Accuracy of Artificial Intelligence for Cervical Vertebral Maturation Assessment-A Systematic Review.

Background/Objectives: To systematically review and summarize the existing scientific evidence on the diagnostic performance of artificial intelligence (AI) in assessing cervical vertebral maturation (CVM). This review aimed to evaluate the accuracy and reliability of AI algorithms in comparison to those of experienced clinicians. Methods: Comprehensive searches were conducted across multiple databases, including PubMed, Scopus, Web of Science, and Embase, using a combination of Boolean operators and MeSH terms. The inclusion criteria were cross-sectional studies with neural network research, reporting diagnostic accuracy, and involving human subjects. Data extraction and quality assessment were performed independently by two reviewers, with a third reviewer resolving any disagreements. The Quality Assessment of Diagnostic Accuracy Studies (QUADAS)-2 tool was used for bias assessment. Results: Eighteen studies met the inclusion criteria, predominantly employing supervised learning techniques, especially convolutional neural networks (CNNs). The diagnostic accuracy of AI models for CVM assessment varied widely, ranging from 57% to 95%. The factors influencing accuracy included the type of AI model, training data, and study methods. Geographic concentration and variability in the experience of radiograph readers also impacted the results. Conclusions: AI has considerable potential for enhancing the accuracy and reliability of CVM assessments in orthodontics. However, the variability in AI performance and the limited number of high-quality studies suggest the need for further research.

Finite element analysis of a three-dimensional cervical spine model with muscles based on CT scan data.

BACKGROUND: The incidence of cervical spondylosis is increasing, gradually affecting people's normal lives. Establishing a finite element model of the cervical spine is one of the methods for studying cervical spondylosis. MRI (Magnetic Resonance Imaging) still has certain difficulties in transitioning from human imaging to establishing muscle models suitable for finite element analysis. Medical software provides specific morphologies and can generate muscle finite element models. Additionally, there is little research on the static analysis of cervical spine finite element models with solid muscle. PURPOSE: A new method is proposed for establishing a finite element model of the cervical spine based on CT (Computed Tomography) data and medical software, and the model's effectiveness is validated. Human movement characteristics based on the force distribution in various parts are analyzed and predicted. METHODS: The muscle model is reconstructed in medical software and a three-dimensional finite element model of the entire cervical spine (C0-C7) is established by combining muscle models with CT vertebral data models. 1.5 Nm of load is applied to the finite element model to simulate the cervical spine movement. RESULTS: The finite element model was successfully established, and effectiveness was verified. Stress variations in various parts under six movements were obtained. The effectiveness of the model was basically verified. CONCLUSION: The finite element model of the cervical spine for mechanical analysis can be successfully established by using medical software and CT data. In daily life, the C2-3, C3-4, C4-C5 intervertebral discs, rectus capitis posterior major, longus colli, and obliquus capitis inferior are more prone to injury.

The hidden value of MRI: modifying treatment decisions in C-spine injuries.

BACKGROUND DATA: Computed Tomography (CT) is the gold standard for cervical spine (c-spine) evaluation. Magnetic resonance imaging (MRI) emerges due to its increasing availability and the lack of radiation exposure. However, MRI is costly and time-consuming, questioning its role in the emergency department (ED). This study investigates the added the value of an additional MRI for patients presenting with a c-spine injury in the ED. METHODS: We conducted a retrospective monocenter cohort study that included all patients with neck trauma presenting in the ED, who received imaging based on the NEXUS criteria. Spine surgeons performed a full-case review to classify each case into "c-spine injured" and "c-spine uninjured". Injuries were classified according to the AO Spine classification. We assessed patients with a c-spine injury detected by CT, who received a subsequent MRI. In this subset, injuries were classified separately in both imaging modalities. We monitored the treatment changes after the additional MRI to evaluate characteristics of this cohort and the impact of the AO Spine Neurology/Modifier modifiers. RESULTS: We identified 4496 subjects, 2321 were eligible for inclusion and 186 were diagnosed with c-spine injuries in the retrospective case review. Fifty-six patients with a c-spine injury initially identified through CT received an additional MRI. The additional MRI significantly extended (geometric mean ratio 1.32, p < 0.001) the duration of the patients' stay in the ED. Of this cohort, 25% had a change in treatment strategy and among the patients with neurological symptoms (AON ≥ 1), 45.8% experienced a change in treatment. Patients that were N-positive, had a 12.4 (95% CI 2.7-90.7, p < 0.01) times higher odds of a treatment change after an additional MRI than neurologically intact patients. CONCLUSION AND RELEVANCE: Our study suggests that patients with a c-spine injury and neurological symptoms benefit from an additional MRI. In neurologically intact patients, an additional MRI retains value only when carefully evaluated on a case-by-case basis.

Exploration of the correlation between facet joints cross-sectional area asymmetry and cervical disc herniation.

PURPOSE: To evaluate the association between facet joints cross-sectional area asymmetry (FCAA) and cervical intervertebral disc herniation (CDH). METHODS: Overall, we retrospectively recruited 390 consecutive patients with CDH who underwent surgical treatment at our institution and 50 normal participants. Clinical variables and radiological findings related to CDH were collected. RESULTS: Patients with CDH were more likely to have a higher absolute value of the facet asymmetry factor (FAF) (p < .001), in which the FAF value of the left group was significantly higher than the other groups (p < .001) and the right group was lower than the central group (p < .001). 9.62% (C3/4), 12.19% (C4/5), 8.70% (C5/6), and 8.14% (C6/7) were determined as cutoff values for each variable that maximized sensitivity and specificity. Furthermore, multivariate analysis showed that cross-sectional area asymmetry of the facet joint (FCAA) was an independent risk factor for the occurrence of CDH. Also, the Chi-square test showed a significant difference in the distribution of the degeneration classification of the disc between the facet-degenerated group and the nondegenerated group at C5/6 (p = 0.026) and C6/7 (p = 0.005) in the facet asymmetry (FA) group. CONCLUSIONS: FCAA is evaluated as an independent risk factor for CDH and associated with the orientation of disc herniation. And facet joint orientation may also play a role in cervical spine degeneration rather than facet joint tropism.

Combined replantation of the posterior arch of the atlas and bilateral axial lamina in the treatment of intradural schwannoma: a case report.

Background: Laminotomy and laminar replantation have emerged as novel treatment modalities for intraspinal tumors, aiming to minimize postoperative complications and retain spinal mobility. However, existing research predominantly emphasizes their application in the thoracolumbar spine. The unique anatomy of the atlantoaxial segments necessitates surgical techniques that differ from those used in other spinal regions, and the clinical effect of such procedure remains unknown. Case presentation: A 61-year-old male patient with intradural schwannoma at the atlantoaxial level was operated on. The patient underwent posterior laminectomy, as well as a combined replantation of the posterior arch of the atlas and bilateral axial laminae. Postoperatively, the patient experienced significant neurological improvement, with no deformities or instability on the radiological assessments during the follow-up. Conclusion: Laminotomy with combined replantation of the posterior arch of the atlas and bilateral axial lamina emerges as an effective approach for managing intraspinal tumors at the atlantoaxial level. This technique not only offers ample operating space but also restores the stability of the spinal canal. Moreover, it preserves the mobility of the atlantoaxial segment, minimizes impact on adjacent segments, and mitigates the formation of postoperative fibrosis.

Estimating mandibular growth stage based on cervical vertebral maturation in lateral cephalometric radiographs using artificial intelligence.

INTRODUCTION: Determining the right time for orthodontic treatment is one of the most important factors affecting the treatment plan and its outcome. The aim of this study is to estimate the mandibular growth stage based on cervical vertebral maturation (CVM) in lateral cephalometric radiographs using artificial intelligence. Unlike previous studies, which use conventional CVM stage naming, our proposed method directly correlates cervical vertebrae with mandibular growth slope. METHODS AND MATERIALS: To conduct this study, first, information of people achieved in American Association of Orthodontics Foundation (AAOF) growth centers was assessed and after considering the entry and exit criteria, a total of 200 people, 108 women and 92 men, were included in the study. Then, the length of the mandible in the lateral cephalometric radiographs that were taken serially from the patients was calculated. The corresponding graphs were labeled based on the growth rate of the mandible in 3 stages; before the growth peak of puberty (pre-pubertal), during the growth peak of puberty (pubertal) and after the growth peak of puberty (post-pubertal). A total of 663 images were selected for evaluation using artificial intelligence. These images were evaluated with different deep learning-based artificial intelligence models considering the diagnostic measures of sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV). We also employed weighted kappa statistics. RESULTS: In the diagnosis of pre-pubertal stage, the convolutional neural network (CNN) designed for this study has the higher sensitivity and NPV (0.84, 0.91 respectively) compared to ResNet-18 model. The ResNet-18 model had better performance in other diagnostic measures of the pre-pubertal stage and all measures in the pubertal and post-pubertal stages. The highest overall diagnostic accuracy was also obtained using ResNet-18 model with the amount of 87.5% compared to 81% in designed CNN. CONCLUSION: The artificial intelligence model trained in this study can receive images of cervical vertebrae and predict mandibular growth status by classifying it into one of three groups; before the growth spurt (pre-pubertal), during the growth spurt (pubertal), and after the growth spurt (post-pubertal). The highest accuracy is in post-pubertal stage with the designed networks.

Orthognathic surgery improves compromised natural head position and pharyngeal airway in patients with Skeletal Class II or III malocclusion.

BACKGROUND: Natural head position (NHP), pharyngeal airway and maxillofacial growth pattern are correlated. The author's previous studies proved that following surgical correction of Skeletal Class II malocclusion, the over-extended NHP returned upright, and the pharyngeal airway space (PAS) dimension expanded. OBJECTIVE: The present study compares the post-operative change in NHP and PAS after orthognathic surgery in Skeletal Class II and III malocclusion patients. METHODS: Patients receiving orthognathic procedures to correct Skeletal Class II or III malocclusions were reviewed in this retrospective study. Pre-operative and 6-week post-operative cone-beam computed tomography datasets were collected. Variables representing the craniofacial pattern, the NHP and the PAS were measured three-dimensionally. Post-operative variables were compared with their pre-operative counterparts using either repeat-measure 2-way analysis of variance or Wilcoxon matched-pairs signed rank test. RESULTS: Thirty cases of Skeletal Class II malocclusion and 13 cases of Skeletal Class III malocclusion were collected. Preoperatively, the inter-group differences were significant in craniofacial pattern (68.14 ± 3.552 degree vs. 79.63 ± 2.497 degree, p < .0001) and the NHP (68.77 ± 11.02 degree vs. 82.83 ± 7.738 degree, p = .0002) while not significant in PAS; after surgery, the intergroup differences in craniofacial pattern and the NHP between groups decreased, and the PAS increased in both groups. CONCLUSION: Orthognathic surgery may improve compromised NHP and increase PAS in Skeletal Class II and III malocclusion patients.

In vivo cervical vertebrae kinematic studies based on dual fluoroscopic imaging system measurement: A narrative review.

Understanding the motion characteristics of cervical spine through biomechanical analysis aids in the identification of abnormal joint movements. This knowledge is essential for the prevention, diagnosis, and treatment of related disorders. However, the anatomical structure of the cervical spine is complex, and traditional medical imaging techniques have certain limitations. Capturing the movement characteristics of various parts of the cervical spine in vivo during motion is challenging. The dual fluoroscopic imaging system (DFIS) is able to quantify the motion and motion patterns of individual segments. In recent years, DFIS has achieved accurate non-invasive measurements of dynamic joint movements in humans. This review assesses the research findings of DFIS about the cervical spine in healthy and pathological individuals. Relevant study search was conducted up to October 2023 in Web of Science, PubMed, and EBSCO databases. After the search, a total of 30 studies were ultimately included. Among them, 13 studies focused on healthy cervical spines, while 17 studies focused on pathological cervical spines. These studies mainly centered on exploring the vertebral bodies and associated structures of the cervical spine, including intervertebral discs, intervertebral foramina, and zygapophyseal joints. Further research could utilize DFIS to investigate cervical spine motion in different populations and under pathological conditions.

Atlantooccipital assimilation associated with combined atlas arch defect: a radiological case report.

In this report, atlantooccipital assimilation (AS), anterior arch defect (AAD), and posterior arch defect (PAD) of the atlas, and several variations around the craniocervical junction were identified on computed tomography (CT) of a patient of unknown sex and age. Coronal and sagittal CT scans showed AS and bilateral fusion of the atlas and the base of occipital bone. Axial CT scan at the atlas revealed PAD type B on the left side and midline AAD. Morphometric measurements indicated a potential ventral spinal cord compression. In addition, mid-sagittal CT revealed the presence of fossa navicularis magna and incomplete formation of the transverse foramen on the right side. This study reports an extremely rare AS associated with AAD, PAD, and other variations of the clivus and the atlas. To our knowledge, no similar case has been reported in the literature.

Mapping an intelligent algorithm for predicting female adolescents' cervical vertebrae maturation stage with high recall and accuracy.

BACKGROUNDS AND OBJECTIVES: The present study was designed to define a novel algorithm capable of predicting female adolescents' cervical vertebrae maturation stage with high recall and accuracy. METHODS: A total of 560 female cephalograms were collected, and cephalograms with unclear vertebral shapes and deformed scales were removed. 480 films from female adolescents (mean age: 11.5 years; age range: 6-19 years) were used for the model development phase, and 80 subjects were randomly and stratified allocated to the validation cohort to further assess the model's performance. Derived significant predictive parameters from 15 anatomic points and 25 quantitative parameters of the second to fourth cervical vertebrae (C2-C4) to establish the ordinary logistic regression model. Evaluation metrics including precision, recall, and F1 score are employed to assess the efficacy of the models in each identified cervical vertebrae maturation stage (iCS). In cases of confusion and mispredictions, the model underwent modification to improve consistency. RESULTS: Four significant parameters, including chronological age, the ratio of D3 to AH3 (D3:AH3), anterosuperior angle of C4 (@4), and distance between C3lp and C4up (C3lp-C4up) were administered into the ordinary regression model. The primary predicting model that implements the novel algorithm was built and the performance evaluation with all stages of 93.96% for accuracy, 93.98% for precision, 93.98% for recall, and 93.95% for F1-score were obtained. Despite the hybrid logistic-based model achieving high accuracy, the unsatisfactory performance of stage estimation was noticed for iCS3 in the primary cohort (89.17%) and validation cohort (85.00%). Through bivariate logistic regression analysis, the posterior height of C4 (PH4) was further selected in the iCS3 to establish a corrected model, thus the evaluation metrics were upgraded to 95.83% and 90.00%, respectively. CONCLUSIONS: An unbiased and objective assessment of the cervical vertebrae maturation (CVM) method can function as a decision-support tool, assisting in the evaluation of the optimal timing for treatment in growing adults. Our novel proposed logistic model yielded individual formulas for each specific CVM stage and attained exceptional performance, indicating the capability to function as a benchmark for maturity evaluation in clinical craniofacial orthopedics for Chinese female adolescents.

Klippel-Feil Syndrome With Isolated Facial Dysmorphism: A Clinical Conundrum With Resemblance to Adenoid Facies.

Klippel-Feil syndrome (KFS) is a triad comprising cervical spine fusion, a low posterior hairline, and constrained neck movement. This triad is not universally present. The most frequent accompaniment is Sprengel's scapula deformity. According to the Feil classification, Class 1 (C1) is an immense fusion of many cervical vertebrae, Class 2 (C2) is a fusion of one or two vertebrae only, and Class 3 (C3) is coupled with thoracic and lumbar spinal vertebral fusion in addition to the fusion of the cervical vertebrae. Clarke's categorization of KFS includes other associated anomalies. The different classification systems for KFS have been made by the different specialists to whom patients may present, which include orthopedic surgeons, neurosurgeons, orthodontists, faciomaxillary surgeons, cardiologists, and pediatricians. This anomaly being rare and the lack of universally accepted classification may lead to confusion regarding the identification of the syndrome, especially the Clarke Type 3 with isolated facial dysmorphism may go undiagnosed. We report a case with KFS-Clarke Type 3 with isolated facial dysmorphism and Feil Type 2 with the fusion of C2-C3 cervical vertebrae, detected as an incidental radiologic finding, and initial impression of adenoid facies. Hence, this case also highlights the contrasting features between the facial dysmorphism of Clarke Type 3 KFS and adenoid facies.