Congenital anomalies of the cervical spine

Prevalence of upper cervical vertebral anomalies in children with non-syndromic cleft lip and/or palate in comparison with children without cleft in Iranian population

BACKGROUND

To evaluate the prevalence of upper cervical vertebral anomalies (CVA) in Iranian children with cleft lip and/or palate (CL/P) and compare it with children without a cleft.

METHODS

A case-control study on lateral cephalograms from Orthodontics Research Center, Shiraz University of Medical Sciences, Shiraz, Iran of 92 subjects (41 females and 51 males) with non-syndromic CL/P with a mean age of 13.54 ± 4.63 years, and 184 age- and sex-matched individuals (82 females and 102 males) with no craniofacial anomalies or skeletal malocclusion as the control group. Upper cervical vertebrae (C1-C3) were examined regarding the following CVA: (1) posterior arch deficiencies: spina bifida and dehiscence; (2) Fusion Anomalies (FAs): fusion and occipitalization; (3) accessory ossicles. Vertebral artery canal morphology was also evaluated.

RESULTS

The prevalence of CVA was significantly higher in the cleft group (62%) than in the control group (25%) (P < 0.001). FAs, fusion, accessory ossicle, and deviation of artery canal type 2 were the anomalies with significantly higher prevalence in the cleft group compared to the noncleft group (all P < 0.05). 11 individuals (11.9%) of the cleft group and five (2.7%) of the control group had more than one CVA. When considering the subgroups of the CL/P, the prevalence of CVA was significantly higher in almost all the CL/P subgroups compared to the control group (all P < 0.05).

CONCLUSIONS

Upper CVA, especially fusion anomalies, were significantly more prevalent in children with non-syndromic CL/P compared to the children without cleft in an Iranian population. A female predilection for CVA was also noted in both the general population and the cleft group.

A new technique: endoscopic transmass odontoidotomy

BACKGROUND & OBJECTIVES

Basilar invagination (BI) represents a complex anomaly of the craniovertebral junction, characterized by the displacement of the odontoid process towards the foramen magnum. Current surgical interventions include anterior decompression and combined anterior-posterior decompression with posterior fusion. Traditional methods for odontoid resection encompass transoral, transnasal, and endonasal approaches. However, these techniques are fraught with significant risks. Furthermore, the restricted exposure provided by the endonasal corridor's anatomical limitations hampers surgical manipulation, prompting spine surgeons to seek alternative techniques. This report details a case of BI managed through an endoscopic posterolateral odontoidotomy, showcasing an innovative surgical approach. We aim to describe our experience in partially removing the odontoid via posterolateral approach with a novel endoscopic technique, preventing the need for additional approach and related complications.

METHODS

A 16-year-old male patient presented with complaints of imbalance and difficulty swallowing. Clinical examination revealed upper extremity muscle weakness, ataxic gait, and dysphagia. Upon the diagnosis of BI, a posterior occipito-cervical fusion was performed. However, six months postoperatively, the patient returned with exacerbated symptoms. During the subsequent surgical intervention, the odontoid body was resected using a posterolateral transmass endoscopic approach. Due to the patient's neck and shoulder anatomy, cranial angulation of the endoscope was restricted, necessitating the retention of the odontoid tip.

RESULTS

Post-operative CT revealed that the tip was closer to the base and a subarachnoid space was formed. Follow-up CT after a year showed a complete migration of the tip to the base of C2 with a clear decompression of the brainstem.

CONCLUSION

Our findings demonstrate that partial or total resection of the odontoid process via a posterolateral approach is feasible using endoscopic techniques. The endoscopic posterolateral transmass odontoidotomy should be considered a viable alternative method and route for patients necessitating partial or total odontoidectomy.

Complications in Occipitocervical Surgery

The occipitocervical junction is formed by the foramen magnum (FM) and the adjacent anatomical structures of the C1 and C2 vertebrae. The FM is formed anteriorly by the basilar part of occipital bone. Anterolaterally, it borders the occipital condyles and hypoglossal canal as well as the jugular foramen. Posteriorly, the FM is formed by the squamous part of the occipital bone with the internal occipital crest. In the midline, named landmarks at the anterior margin are the basion and, at the posterior margin, the opisthion. Vital anatomic structures are located in the FM or pass through. Among these are the medulla oblongata, meninges, anterior and posterior spinal arteries, vertebral arteries, and spinal roots of the accessory nerve. The FM is firmly anchored to the cervical canal via strong ligamentous support.Pathologies in this area can be of congenital, acquired, traumatic, neoplastic, or infectious origin, with the respective surgical indications and approaches depending on the nature and location of the pathology. If the pathology is occipitoatlantal, the occiput is usually involved in surgery. On the other hand, if the pathology is only at the level of C1-C2, surgery may be limited to these two vertebrae.In this section, we present the surgical management of exemplary congenital cases, and we discuss the complications and what needs to be done to deal with them.

The ligamentous cervical instability etiology of human disease from the forward head-facedown lifestyle: emphasis on obstruction of fluid flow into and out of the brain

Ligamentous cervical instability, especially ligamentous upper cervical instability, can be the missing structural cause and/or co-morbidity for many chronic disabling brain and systemic body symptoms and diagnoses. Due to the forward head-facedown lifestyle from excessive computer and cell phone usage, the posterior ligament complex of the cervical spine undergoes a slow stretch termed "creep" which can, over time, lead to cervical instability and a breakdown of the cervical curve. As this degenerative process continues, the cervical curve straightens and ultimately becomes kyphotic, a process called cervical dysstructure; simultaneously, the atlas (C1) moves forward, both of which can lead to encroachment of the structures in the carotid sheath, especially the internal jugular veins and vagus nerves. This obstruction of fluid flow can account for many brain diseases, and compression and stretch of the vagus nerve for body diseases, including dysautonomia. This article describes the consequences of impaired fluid flow into and out of the brain, especially venous flow through the internal jugular veins, leading to intracranial hypertension (formerly called pseudotumor cerebri). Cervical structural, internal jugular vein, and optic nerve sheath measurements are presented from a retrospective chart review of 227 consecutive patients with no obvious cause for 1 of 8 specific brain or mental health symptoms-anxiety, brain fog, concentration difficulty, depression/hopelessness, headaches, obsessive thoughts, panic attacks, and rumination on traumatic events. A case example is given to demonstrate how cervical structural treatments can open up internal jugular veins and improve a patient's chronic symptoms.

Challenges in Contemporary Spine Surgery: A Comprehensive Review of Surgical, Technological, and Patient-Specific Issues

Spine surgery has significantly progressed due to innovations in surgical techniques, technology, and a deeper understanding of spinal pathology. However, numerous challenges persist, complicating successful outcomes. Anatomical intricacies at transitional junctions demand precise surgical expertise to avoid complications. Technical challenges, such as underestimation of the density of fixed vertebrae, individual vertebral characteristics, and the angle of pedicle inclination, pose additional risks during surgery. Patient anatomical variability and prior surgeries add layers of difficulty, often necessitating thorough pre- and intraoperative planning. Technological challenges involve the integration of artificial intelligence (AI) and advanced visualization systems. AI offers predictive capabilities but is limited by the need for large, high-quality datasets and the "black box" nature of machine learning models, which complicates clinical decision making. Visualization technologies like augmented reality and robotic surgery enhance precision but come with operational and cost-related hurdles. Patient-specific challenges include managing postoperative complications such as adjacent segment disease, hardware failure, and neurological deficits. Effective patient outcome measurement is critical, yet existing metrics often fail to capture the full scope of patient experiences. Proper patient selection for procedures is essential to minimize risks and improve outcomes, but criteria can be inconsistent and complex. There is the need for continued technological innovation, improved patient-specific outcome measures, and enhanced surgical education through simulation-based training. Integrating AI in preoperative planning and developing comprehensive databases for spinal pathologies can aid in creating more accurate, generalizable models. A holistic approach that combines technological advancements with personalized patient care and ongoing education is essential for addressing these challenges and improving spine surgery outcomes.

Short-term effects of low-level laser versus ultrasound therapy on children's neck posture after long-term use of electronic devices

The purpose of the study was to compare the effect of low-level laser therapy (LLLT), ultrasound therapy (US), and strengthening and stretching exercise in children diagnosed with cervical straightening caused by long-term use of electronic devices. A total of 60 patients from 12 to 18 years of both gender diagnosed with straight neck syndrome which is losing the normal C shape of cervical vertebrae. Patients were randomized into three groups. In group A, patients received LLLT plus exercise, while in group B, they received US plus exercise, and group C received exercise. In group A and B, Cobb angle and VAS showed a significant improvement (more significant in group A) with P < 0.001, while in group C P = 0.006. LLLT, US, and exercise improved the cervical straight curve, and reduced pain with maximum effect was done by LLLT.

Pediatric Spinal Cord Injury: A Review

A spinal cord injury (SCI) can be a devastating condition in children, with profound implications for their overall health and quality of life. In this review, we aim to provide a concise overview of the key aspects associated with SCIs in the pediatric population. Firstly, we discuss the etiology and epidemiology of SCIs in children, highlighting the diverse range of causes. We explore the unique anatomical and physiological characteristics of the developing spinal cord that contribute to the specific challenges faced by pediatric patients. Next, we delve into the clinical presentation and diagnostic methods, emphasizing the importance of prompt and accurate diagnosis to facilitate appropriate interventions. Furthermore, we approach the multidisciplinary management of pediatric SCIs, encompassing acute medical care, surgical interventions, and ongoing supportive therapies. Finally, we explore emerging research as well as innovative therapies in the field, and we emphasize the need for continued advancements in understanding and treating SCIs in children to improve their functional independence and overall quality of life.

Giant Anomalous Cervical Spinous Process Causing Dynamic Cord Compression: An Unusual Cause for Myelopathy: A Case Report

CASE

A 47-year-old male patient presented with progressively worsening gait instability caused by a giant anomalous, free-floating C5 spinous process resulting in dynamic cord compression and myelopathy. The patient was successfully managed with a C5 laminectomy and total excision of the anomalous spinous process with a good functional outcome at the final follow-up.

CONCLUSION

Anomalies of the posterior arch of the subaxial cervical spine are relatively uncommon and asymptomatic. This case is being reported for its rarity and to highlight the role of dynamic imaging in patients presenting with congenital anomalies of the cervical spine presenting with compressive myelopathy.

Clinical application of spinal robot in cervical spine surgery: safety and accuracy of posterior pedicle screw placement in comparison with conventional freehand methods

The novel robot-assisted (RA) technique has been utilized increasingly to improve the accuracy of cervical pedicle screw placement. Although the clinical application of the RA technique has been investigated in several case series and comparative studies, the superiority and safety of RA over conventional freehand (FH) methods remain controversial. Meanwhile, the intra-pedicular accuracy of the two methods has not been compared for patients with cervical traumatic conditions. This study aimed to compare the rate and risk factors of intra-pedicular accuracy of RA versus the conventional FH approach for posterior pedicle screw placement in cervical traumatic diseases. A total of 52 patients with cervical traumatic diseases who received cervical screw placement using RA (26 patients) and FH (26 patients) techniques were retrospectively included. The primary outcome was the intra-pedicular accuracy of cervical pedicle screw placement according to the Gertzbin-Robbins scale. Secondary outcome parameters included surgical time, intraoperative blood loss, postoperative drainage, postoperative hospital stay, and complications. Moreover, the risk factors that possibly affected intra-pedicular accuracy were assessed using univariate analyses. Out of 52 screws inserted using the RA method, 43 screws (82.7%) were classified as grade A, with the remaining 7 (13.5%) and 2 (3.8%) screws classified as grades B and C. In the FH cohort, 60.8% of the 79 screws were graded A, with the remaining screws graded B (21, 26.6%), C (8, 10.1%), and D (2, 2.5%). The RA technique showed a significantly higher rate of optimal intra-pedicular accuracy than the FH method (P = 0.008), but there was no significant difference between the two groups in terms of clinically acceptable accuracy (P = 0.161). Besides, the RA technique showed remarkably longer surgery time, less postoperative drainage, shorter postoperative hospital stay, and equivalent intraoperative blood loss and complications than the FH technique. Furthermore, the univariate analyses showed that severe obliquity of the lateral atlantoaxial joint in the coronal plane (P = 0.003) and shorter width of the lateral mass at the inferior margin of the posterior arch (P = 0.014) were risk factors related to the inaccuracy of C1 screw placement. The diagnosis of HRVA (P < 0.001), severe obliquity of the lateral atlantoaxial joint in the coronal plane (P < 0.001), short pedicle width (P < 0.001), and short pedicle height (P < 0.001) were risk factors related to the inaccuracy of C2 screw placement. RA cervical pedicle screw placement was associated with a higher rate of optimal intra-pedicular accuracy to the FH technique for patients with cervical traumatic conditions. The severe obliquity of the lateral atlantoaxial joint in the coronal plane independently contributed to high rates of the inaccuracy of C1 and C2 screw placements. RA pedicle screw placement is safe and useful for cervical traumatic surgery.

CT and MRI characterization of presumed persistent ossiculum terminale in dogs

Anecdotally, during the review of CT and MRI studies of canine patients including the cranial cervical spine, authors have identified a small osseous structure between the atlas (C1) and axis (C2) with no relevant clinical signs. This structure appeared comparable to a "persistent ossiculum terminale" in humans. The aim of this retrospective, multi-center, case series study was to describe the CT and MRI features of presumed persistent ossiculum terminale in a group of dogs presented with unrelated medical conditions.  Two databases (the imaging database of the teleradiology service VetCT Specialists and the clinical database of the University of Vienna) were scrutinized by different approaches. Medical records of dogs that underwent imaging investigation (CT and/or MRI) that included the atlanto-axial junction were reviewed. Data collected included signalment, sex, breed, age, presenting symptoms, and final diagnosis. Eighteen dogs met the inclusion criteria. Mean age was 85 months (6-166) and breed variation was present. A total of 20 imaging studies were evaluated: CT was performed in 17 dogs; MRI in three dogs; two dogs had both MRI and CT performed. In all cases the presence of at least one small osseous body on the cranial aspect of the odontoid process compatible with a persistent ossiculum terminale was identified as a possible incidental finding without any overt clinical implications. Findings indicated that a small osseous body on the cranial aspect of the odontoid process (presumed persistent ossiculum terminale) in CT and MRI studies may be present in dogs with no clinical signs of neurologic disease.

New insights in craniovertebral junction MR changes leading to stenosis in children with achondroplasia

PURPOSE

To characterize natural history and early changes of craniovertebral junction stenosis in achondroplasia correlating with clinical and radiological outcome.

METHODS

Retrospective measures on craniovertebral junction were performed blindly, on sagittal T2-weighted images, in 21 patients with achondroplasia referred from 2008 to 2020. Clinical and polysomnography data were retrospectively collected. Each patient was paired for age and gender with four controls. Wilcoxon means comparison or Student's t-tests were applied.

RESULTS

Twenty-one patients (11 females, from 0.1 to 39 years of age) were analyzed and paired with 84 controls. A craniovertebral junction stenosis was found in 11/21 patients (52.4%), all before the age of 2 years. Despite a significant reduction of the foramen magnum diameter (mean ± SD: patients 13.6 ± 6.2 mm, controls 28.5 ± 4.7 mm, p < .001), craniovertebral junction stenosis resulted from the narrowing of C2 dens-opisthion antero-posterior diameter (8.7 ± 3.9 mm vs 24.6 ± 5.1 mm, p < .001). Other significant changes were opisthion anterior placement (-0.4 ± 2.8 mm vs 9.4 ± 2.3 mm, p < .001), posterior tilt of C2 (46.2 ± 13.7° vs 31.6 ± 7.9°, p < .001) and of C1 (15.1 ± 4.3° vs 11.9 ± 5.0°, p = 0.01), and dens thickening (9.4 ± 2.2 mm vs 8.5 ± 2.1 mm, p = 0.03), allowing to define three distinguishable early craniovertebral junction patterns in achondroplasia. All children with C2-opisthion antero-posterior diameter of more than 6 mm had a better clinical and radiological outcome.

CONCLUSION

Craniovertebral junction in achondroplasia results from narrowing between C2 dens and opisthion related to anterior placement of opisthion, thickening of C2 dens, and posterior tilt of C1-C2. A threshold of 6 mm for dens-opisthion sagittal diameter seems to correlate with clinical and radiological outcome.

Cervical fusion for adult patients with atlantoaxial rotatory subluxation

BACKGROUND

Atlantoaxial rotatory subluxation (AARS) is a rare injury of the C1/C2 junction. It is often associated with trauma in adults. Treatment may depend on the duration of symptoms and clinical presentation, but there is no consensus regarding the ideal management of these injuries. Our objective is to ascertain the prevalence of neurological deficit, complications, and outcomes of patients diagnosed with AARS undergoing cervical fusion (CF) versus those treated without CF.

METHODS

The 2016-2019 National Inpatient Sample (NIS) was queried using International Classification of Diseases, 10th revision (ICD-10) for adult patients with C1/C2 subluxation. Patients undergoing CF were defined through ICD-10 procedure codes. Baseline health and acute illness severity was calculated using the 11-point modified frailty index (mFI-11). Presenting characteristics, treatment complications, and outcomes were evaluated of CF vs. non-CF patients.

RESULTS

Of 990 adult patients with AARS, 720 were treated without CF and 270 were treated with CF. CF patients were more often myelopathic. Patients that had undergone CF treatment were negatively associated with having had extensive trauma. Patients undergoing CF experienced significantly longer length of stay (LOS), increased healthcare resource utilization, and decreased inpatient mortality. Sepsis had a negative association with patients that underwent CF treatment while pneumonia had a positive association.

CONCLUSIONS

Adult patients undergoing CF for AARS demonstrated an increase in healthcare resource utilization but also a significant decrease in mortality. Extent of acute injury appears to have a strong influence on decision making for CF. Further study of decision making for treatment of this rare injury in adults is warranted.

Spinal Cord Medial Safe Zone for C2 Pedicle Instrumentation: An MRI Measurement Analysis

STUDY DESIGN

Retrospective observational study.

OBJECTIVE

The aim of this study was to investigate the spinal cord safety margins for C2 instrumentation.

SUMMARY OF BACKGROUND DATA

Intraoperative spinal cord injury during C2 spine surgery is a rare, but potentially life-threatening complication. Preoperative planning for C2 instrumentation mainly focuses on C2 pedicle bony dimensions on CT and the vertebral artery location and few studies have evaluated C2 spinal cord safety margins.

METHODS

We measured two distances in C2 bilaterally: C2 pedicle to dura distance (P-D), defined as a transverse line that measured the shortest distance between the medial wall of the C2 pedicle and the dural sac, and C2 pedicle to spinal cord (P-SC), defined as a transverse line that measured the shortest distance between the medial wall of the C2 pedicle and spinal cord. We defined the distances >4 mm as safe for instrumentation.

RESULT

A total of 146 patients (mean age 71.2, 50.7% female) were included. The average distances were 5.5 mm for C2 left PD, 5.9 mm for C2 right P-D, 10.1 mm for C2 left P-SC, and 10.6 mm for C2 right P-SC. Twenty-eight (21.4%) patients had C2 P-D distances <4 mm and of those two (7%) patients had distances <2 mm. There were more female patients with C2 P-D distances under 4 mm compared to males. No patient had C2 P-SC distances <4 mm.

CONCLUSION

We demonstrated that around 20% of patients had C2 P-D distance <4 mm, but no patient had C2 P-SC distance <4 mm. Since a lateral misplacement can lead to a potentially fatal vertebral artery injury, medial screw trajectory is recommended for C2 pedicle instrumentation with consideration of these safety margins.Level of Evidence: 3.

Bilateral Thoracic Outlet Syndrome from Anomalous 8th Cervical Vertebrae Ribs

Thoracic outlet syndrome (TOS) is a group of diverse disorders resulting from compression of neurovascular structures as they pass from the lower neck to upper limb. Neurological symptoms, such as pain, weakness, or paraesthesia, are much more common than vascular symptoms such as pallor or venous congestion. Anatomical abnormalities can contribute to this condition. Thirty percent of patients with TOS can have a cervical rib, arising from the transverse process of the 7th cervical vertebra, compared with 1% of the general population. We report the first case in the literature of neurogenic TOS from a cervical rib arising from a supernumerary 8th cervical vertebra. This patient had immediate improvement in TOS symptoms following scalene muscle surgery and resection of cervical and first thoracic ribs.

Posterior midline approach to odontoidectomy: A novel method to treat basilar invagination

Background:

Basilar invagination (BI) is a common malformation of the craniocervical region where the odontoid process protrudes into the foramen magnum. Surgery in this region is difficult because of the complex anatomy of the craniocervical junction. Serious life-threatening complications have been observed with previously described approaches. Therefore, we conceived a novel surgical approach that can be implemented by neurosurgeons with different skill levels to facilitate better outcomes.

Methods:

We describe a new surgical technique for the treatment of BI that we used in two patients in whom cervical myelopathy and direct ventral compression of the cervicomedullary junction were confirmed through clinical and radiological findings. We present the technique of posterior odontoidectomy in a step-by-step, didactic, and practical manner with surgical tips and tricks.

Results:

The resection was completed without intraoperative or postoperative complications in both cases. The patients experienced substantial neurological improvements, and full recovery was observed during the 9-month and 12-month follow-up visits after discharge. Compared with the transoral approach, our technique provides a larger decompression area.

Conclusions:

We describe a novel method for the treatment of BI that was applied in two patients and suggest that the posterior approach might be a safe and effective method for ventral decompression of the craniocervical junction. Posterior odontoidectomy followed by craniocervical fixation helped achieve complete cervicomedullary decompression.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group

BACKGROUND

The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.

METHODS

In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.

RESULTS

Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.

CONCLUSIONS

Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Consensus practice guidelines on interventions for cervical spine (facet) joint pain from a multispecialty international working group

BACKGROUND

The past two decades have witnessed a surge in the use of cervical spine joint procedures including joint injections, nerve blocks and radiofrequency ablation to treat chronic neck pain, yet many aspects of the procedures remain controversial.

METHODS

In August 2020, the American Society of Regional Anesthesia and Pain Medicine and the American Academy of Pain Medicine approved and charged the Cervical Joint Working Group to develop neck pain guidelines. Eighteen stakeholder societies were identified, and formal request-for-participation and member nomination letters were sent to those organizations. Participating entities selected panel members and an ad hoc steering committee selected preliminary questions, which were then revised by the full committee. Each question was assigned to a module composed of 4-5 members, who worked with the Subcommittee Lead and the Committee Chairs on preliminary versions, which were sent to the full committee after revisions. We used a modified Delphi method whereby the questions were sent to the committee en bloc and comments were returned in a non-blinded fashion to the Chairs, who incorporated the comments and sent out revised versions until consensus was reached. Before commencing, it was agreed that a recommendation would be noted with >50% agreement among committee members, but a consensus recommendation would require ≥75% agreement.

RESULTS

Twenty questions were selected, with 100% consensus achieved in committee on 17 topics. Among participating organizations, 14 of 15 that voted approved or supported the guidelines en bloc, with 14 questions being approved with no dissensions or abstentions. Specific questions addressed included the value of clinical presentation and imaging in selecting patients for procedures, whether conservative treatment should be used before injections, whether imaging is necessary for blocks, diagnostic and prognostic value of medial branch blocks and intra-articular joint injections, the effects of sedation and injectate volume on validity, whether facet blocks have therapeutic value, what the ideal cut-off value is for designating a block as positive, how many blocks should be performed before radiofrequency ablation, the orientation of electrodes, whether larger lesions translate into higher success rates, whether stimulation should be used before radiofrequency ablation, how best to mitigate complication risks, if different standards should be applied to clinical practice and trials, and the indications for repeating radiofrequency ablation.

CONCLUSIONS

Cervical medial branch radiofrequency ablation may provide benefit to well-selected individuals, with medial branch blocks being more predictive than intra-articular injections. More stringent selection criteria are likely to improve denervation outcomes, but at the expense of false-negatives (ie, lower overall success rate). Clinical trials should be tailored based on objectives, and selection criteria for some may be more stringent than what is ideal in clinical practice.

Congenital Cervical Hemivertebrae and Block Vertebrae in a 43-Year-Old Male

Congenital deformities of the spine are a consequence of anomalous vertebral development in the embryo and may be identified at birth or remain unnoticed until adulthood. Minor bony malformations of all types occur in up to 12% of the general population and are usually not apparent. In contrast, congenital spinal malformations that result in progressive spinal deformity are relatively rare. Klippel-Feil syndrome is a complex heterogeneous entity that results in cervical vertebral fusion and sometimes can occur associated to hemivertebra. We present a case of a 43-year-old male who presented to the emergency department after a fall. The patient had severe cervicalgia and generalized loss of active movement and sensation on his limbs. On physical examination, the patient presented reduced cervical range of motion and tetraplegia. Cervical magnetic resonance imaging revealed complete atlanto-occipital assimilation, left C3 hemivertebra with partial fusion in the right lateral portion of C2 and C4. Finally, there was a C5-C6 fusion. Surgical cervical stabilization was attempted but the procedure was aborted due to lack of space for placing the anterior plate safely. During hospitalization, the patient wore a cervical collar and started a rehabilitation program including muscle strengthening, balance, and gait training. The rehabilitation treatment led to a favorable clinical evolution. At discharge, the patient maintained a slight deficit of strength in his left upper and lower extremities, but he was functionally autonomous and was able to walk with a walker.

An unusual injury mechanism of atlantoaxial dislocation: illustrative case

BACKGROUND

Atlantoaxial dislocation (AAD) is a rare and potentially life-threatening condition. Various underlying mechanisms of injury are described in the literature. Here, the authors report an unusual nontraumatic injury mechanism of AAD in a 12-year-old patient.

OBSERVATIONS

A 12-year-old boy presented with intolerable neck pain and numbness in both upper limbs. The patient’s symptoms had started 2 months after the initiation of online classes during the coronavirus disease 2019 pandemic without a history of trauma. He used a computer for personal study and online classes for prolonged hours with no respite. On physical and radiological evaluation, he was diagnosed with AAD. Before surgery, skull traction was applied to reduce the dislocation and posterior C1 lateral mass screw and C2 pedicle screw fixation was performed. An optimal clinical outcome was achieved with no postoperative complications. A preoperative visual analog scale score of 8.0 was reduced to 0 postoperatively.

LESSONS

A prolonged fixed neck posture is an unusual underlying cause of AAD. Posterior C1 lateral mass and C2 pedicle screw fixation results in an optimal clinical outcome.

Axis spinous process malformations are commonly identified in a sample of English Bull Terriers without associated clinical signs

Congenital cervical vertebral malformations (CCVM) have been infrequently reported in veterinary medicine, with limited examples of axis spinous process malformations. The objective of this retrospective cross-sectional study was to describe the radiological characteristics, prevalence, and clinical relevance of a characteristic axis vertebral malformation in a sample of English Bull Terriers (EBTs). Medical records and diagnostic imaging studies of the cervical vertebral column of EBTs presenting for any reason were reviewed and described. Based on evaluation of the images, EBTs were divided in two groups; axis spinous process malformation and normal cases. Referring veterinary surgeons were contacted for long-term follow-up information. A total of 27 cervical radiographs, 23 CT, and nine MRI studies from 53 EBTs were reviewed. An axis spinous process malformation, characterized by a linear defect of varying length along the base of the spinous process, was identified in 22 of 53 EBTs (41.5%). There was no significant difference in age, body weight, or sex (P < .05) between EBTs with and without the malformation. No traumatic causes or clinical signs were identified in EBTs with the malformation that could be directly attributed to it. To the authors' knowledge, this is the first report of a malformation of the axis spinous process in a sample of EBTs. The malformation was not associated with clinical signs and should not be misinterpreted as a traumatic vertebral fracture or other pathology.

Vertebral Artery Variation in Patients With Congenital Cervical Scoliosis: An Anatomical Study Based on Radiological Findings

STUDY DESIGN

Observational, anatomical, radiological study.

OBJECTIVE

The aim of this study was to explore the incidence and type of vertebral artery (VA) variation in patients with congenital cervical scoliosis and approach their clinical importance during surgery.

SUMMARY OF BACKGROUND DATA

Congenital scoliosis of the cervical spine is usually sporadic and caused by a variety of bone structural anomalies. Most of the cases remain asymptomatic. Surgical intervention is the main management for patients with neurological compromise or with cosmetic demands. The operation involved more screw insertion and osteotomy than the regular degenerative cases. The incidence and pattern of VA variants in these patients have not been reported.

METHODS

Patients with congenital cervical scoliosis treated in our department were reviewed. We measured Cobb angle of cervical spine. We observed bilateral VAs and recorded variants. We measured their diameter in each segment through CT angiography. The bilateral diameter in each patient was then compared respectively.

RESULT

There is a total of 44 patients enrolled. The incidence of VA variation was 41% (18/44). Fifty percent (22/44) of patients had the dominant VA with no difference between concave side and convex side. Patients with a dominant VA had a larger Cobb angle than those who had not (30.25° vs. 23.24°, P < 0.05). The courses of VA were abnormal in 18 patients. Two patients had unilateral variant in V1 segment. Twelve patients had variants in V2 segment. Eight patients had variants in V3 segment. Three patients had VA variants in multiple sites.

CONCLUSION

In patients with congenital cervical scoliosis, the dominance of VA is not related to the convex side or concave side, but patients with a dominance of VA have a larger Cobb angle. The incidence of variant in V2 and V3 segment is higher. A thorough evaluation of bilateral VAs is required before surgery. Extra cautions must be taken during surgery.Level of Evidence: 5.

Comparative proteomics analysis for identifying the lipid metabolism related pathways in patients with Klippel-Feil syndrome

Background

Klippel-Feil syndrome (KFS) represents the rare and complex deformity characterized by congenital defects in the formation or segmentation of the cervical vertebrae. There is a wide gap in understanding the detailed mechanisms of KFS because of its rarity, heterogeneity, small pedigrees, and the broad spectrum of anomalies.

Methods

We recruited eight patients of Chinese Han ethnicity with KFS, five patients with congenital scoliosis (CS) who presented with congenital fusion of the thoracic or lumbar spine and without known syndrome or cervical deformity, and seven healthy controls. Proteomic analysis by data-independent acquisition (DIA) was performed to identify the differential proteome among the three matched groups and the data were analyzed by bioinformatics tools including Gene Ontology (GO) categories and Ingenuity Pathway Analysis (IPA) database, to explore differentially abundant proteins (DAPs) and canonical pathways involved in the pathogenesis of KFS.

Results

A total of 49 DAPs were detected between KFS patients and the controls, and moreover, 192 DAPs were identified between patients with KFS and patients with CS. Fifteen DAPs that were common in both comparisons were considered as candidate biomarkers for KFS, including membrane primary amine oxidase, noelin, galectin-3-binding protein, cadherin-5, glyceraldehyde-3-phosphate dehydrogenase, peroxiredoxin-1, CD109 antigen, and eight immunoglobulins. Furthermore, the same significant canonical pathways of LXR/RXR activation and FXR/RXR activation were observed in both comparisons. Seven of DAPs were apolipoproteins related to these pathways that are involved in lipid metabolism.

Conclusions

This study provides the first proteomic profile for understanding the pathogenesis and identifying predictive biomarkers of KFS. We detected 15 DAPs that were common in both comparisons as candidate predictive biomarkers of KFS. The lipid metabolism-related canonical pathways of LXR/RXR and FXR/RXR activation together with seven differentially abundant apolipoproteins may play significant roles in the etiology of KFS and provide possible pathogenesis correlation between KFS and CS.

Later Surgical Start Time Is Associated With Longer Length of Stay and Higher Cost in Cervical Spine Surgery

STUDY DESIGN

Retrospective study of a surgical cohort from a single, large academic institution.

OBJECTIVE

The aim of this study was to investigate associations between surgical start time, length of stay, cost, perioperative outcomes, and readmission.

SUMMARY OF BACKGROUND DATA

One retrospective study with a smaller cohort investigated associations between surgical start time and outcomes in spine surgery and found that early start times were correlated with shorter length of stay. No examinations of perioperative outcomes or cost have been performed.

METHODS

All patients undergoing anterior cervical discectomy and fusion (ACDF) and posterior cervical decompression and fusion (PCDF) were queried from a single institution from January 1, 2008 to November 30, 2016. Patients undergoing surgery that started between 12:00 AM and 6:00 AM were excluded due to their likely emergent nature. Cases starting before and after 2:00 PM were compared on the basis of length of stay and cost as the primary outcomes using multivariable logistic regression.

RESULT

The patients undergoing ACDF and PCDF were both similar on the basis of comorbidity burden, preoperative diagnosis, and number of segments fused. The patients undergoing ACDF starting after 2 PM had longer LOS values (adjusted difference of 0.65 days; 95% confidence interval [CI]: 0.28-1.03; P = 0.0006) and higher costs of hospitalization (adjusted difference of $1177; 95% CI: $549-$1806; P = 0.0002). Patients undergoing PCDF starting after 2 PM also had longer LOS values (adjusted difference of 1.19 days; 95% CI: 0.46-1.91; P = 0.001) and higher costs of hospitalization (adjusted difference of $2305; 95% CI: $826-$3785; P = 0.002).

CONCLUSION

Later surgical start time is associated with longer LOS and higher cost. These findings should be further confirmed in the spine surgical literature to investigate surgical start time as a potential cost-saving measure.

LEVEL OF EVIDENCE

3.

Chiari malformation type I and basilar invagination originating from atlantoaxial instability: a literature review and critical analysis

Introduction

Recently, a novel hypothesis has been proposed concerning the origin of craniovertebral junction (CVJ) abnormalities. Commonly found in patients with these entities, atlantoaxial instability has been suspected to cause both Chiari malformation type I and basilar invagination, which renders the tried and tested surgical decompression strategy ineffective. In turn, C1-2 fusion is proposed as a single solution for all CVJ abnormalities, and a revised definition of atlantoaxial instability sees patients both with and without radiographic evidence of instability undergo fusion, instead relying on the intraoperative assessment of the atlantoaxial joints to confirm instability.

Methods

The authors conducted a comprehensive narrative review of literature and evidence covering this recently emerged hypothesis. The proposed pathomechanisms are discussed and contextualized with published literature.

Conclusion

The existing evidence is evaluated for supporting or opposing sole posterior C1-2 fusion in patients with CVJ abnormalities and compared with reported outcomes for conventional surgical strategies such as posterior fossa decompression, occipitocervical fusion, and anterior decompression. At present, there is insufficient evidence supporting the hypothesis of atlantoaxial instability being the common progenitor for CVJ abnormalities. Abolishing tried and tested surgical procedures in favor of a single universal approach would thus be unwarranted.

Complete Atlantoaxial Dislocation After Odontoid Synchondrosis Fracture: A 2-Year Follow-up Study: A Case Report

CASE

Spine injuries are rare in children, but when they do occur, the synchondrosis of C2 may be involved. A 5-year-old boy presented to our clinic complaining of neck pain for 6 weeks, which started after wrestling with peers. He had slight upper extremity weakness, clonus, and diminished reflexes. Imaging, including computed tomography and magnetic resonance imaging scans, showed a fracture dislocation through the synchondrosis of the odontoid. The patient was initially treated with admission to the hospital, awake halo placement, and gradual traction over a few days. Subsequently, he was taken for transoral reduction and posterior instrumented fusion of C1-C3 using a combination of sublaminar suture, screws, and rods. Most recently, he was doing well over 2 years later, with no residual neurologic symptoms.

CONCLUSIONS

The case presented demonstrates one option for an otherwise nonreducible odontoid synchondrosis fracture with complete atlantoaxial dislocation: transoral reduction and open posterior instrumentation. This proved to be a practical technique and provided a good clinical result in this case. These injuries are rare, but when they do occur, the examination can be surprisingly subtle given the severity of the injury. Plain films should be scrutinized carefully and advanced imaging obtained when necessary to confirm the diagnosis.

Developmental anomalies and South American paleopathology: A comparison of block vertebrae and co-occurring axial anomalies among three skeletal samples from the El Brujo archaeological complex of northern coastal Peru

Though developmental anomalies have been noted for over a century in South American paleopathology, they have received less attention than other pathological conditions. When anomalies are reported, they tend to be unusual case studies or incidental findings. Paleopathological research should also consider anomalies from a population perspective, to broaden our understanding about the frequency of specific anomalies, and potentially offer insight into genetic relationships, cultural behavior, or environmental factors. This investigation compared block vertebrae and co-occurring postcranial axial anomalies among three skeletal samples reflecting an occupational sequence at the El Brujo Archaeological Complex of Peru. Block vertebrae demonstrate both considerable antiquity and persistence through time, though frequencies, vertebral level, and co-occurring anomalies varied by sex and cultural period. Among the Late Preceramic sample, the frequency of C2-C3 block vertebrae was highest and only seen among females, which may suggest familial influence, genetic isolation, and potentially matrilocality. The Moche sample demonstrated a moderate frequency of blocks, which in combination with the frequencies of other developmental anomalies, may suggest population continuity paired with an influx of new genes, demographic expansion, and possible cultural change with regard to postmarital residence. The Lambayeque sample demonstrated the lowest frequency of blocks and the highest frequency and greatest diversity of anomalies, which may suggest genetic continuity from the Moche, an expanded gene pool, broader opportunities for mate choice, and cultural change. It is hoped that this investigation will provide data for future comparisons and call attention to the need for the broader study of developmental anomalies in South America.

Anatomical analysis of the occipital bone in patients with basilar invagination: a computed tomography-based study

BACKGROUND CONTEXT

The occipital bone is often involved in the surgical treatment of basilar invagination (BI). However, the anatomy of the occipital bone associated with BI patients has yet to be investigated.

PURPOSE

To present a morphological map of the occipital bone in BI patients and help guide screw placement for occipitocervical fusion.

STUDY DESIGN

A retrospective case-control study.

METHODS

Radiological measurements of the occipital bone were performed on computed tomography images based on a matrix of 99 points centered around the external occipital protuberance (EOP) in a cohort of 50 BI patients and 50 cases with no head and cervical disease. The comparison between the BI group and the control group was assessed using Student t analysis and p<.05 was considered statistically significant.

RESULTS

All thicknesses measured from points of the matrix in the BI group were thinner than those in the control group (p<.05). The maximum thicknesses in both groups were located at the center of the EOP, which were 15.11±2.84 mm in the BI group and 17.56±3.03 mm in the control group, respectively. Additionally, thickness decreased with the distance away from the center of EOP.

CONCLUSIONS

The occipital bone in BI patients is thinner than that in the general population. A limited safe zone in BI patients is available for surgeons to place screws, which may need to be fully evaluated before operation.

Unilateral atlantoaxial pseudoarticulation: A case report, literature review, and proposed mechanism

Background

Atlantoaxial pseudoarticulation rarely involves the cervical spine, and its etiology is unclear. In theory, pseudoarticulation is comparable to Bertolotti's syndrome in the lumbar spine or may be attributed to an aberrant focal fusion between C0-C1-C2 that occurs during the gastrulation of embryologic development.

Case Description

A 39-year-old female presented with neck pain and upper extremity weakness. Magnetic resonance/computed tomography studies documented a left-sided unilateral pseudoarticulation between the lamina of C1 and C2 causing compression of the dorsal spinal cord. Following resection of the accessory C1/C2 joint utilizing a C1 hemilaminectomy and partial C2 laminectomy, the patient's neck pain and weakness resolved. Histologically, the tissue showed benign osteocartilaginous tissue with no synovial capsule.

Conclusion

Here, the authors present a case of occiput-C1-C2 pseudojoint formation, leading to clinical and radiographic findings of cord compression due to boney outgrowth.

Traumatic posterior Atlanto-axial dislocation: case report of an atypical C1-C2 dislocation with an anterior arch fracture of C1

Background

An atypical case of a traumatic posterior C1-C2 dislocation with an anterior arch fracture of C1 is reported. A novel conservative treatment for this rare lesion is described.

Case presentation

An eighty-nine-year-old male fell off a ladder at home and presented with an acute traumatic cervical spine trauma, which we believe involved a distraction mechanism. The patient was neurologically intact; he denied any weakness, numbness or paresthesia. A preoperative CT-scan demonstrated a posterior dislocation with an anterior arch of C1 fracture. Conservative management was elected. Reduction was achieved by closed manual reduction under general anesthesia. A postoperative CT demonstrated a complete reduction of the atlanto-axial dislocation.

Conclusion

Based on this case report and relevant literature, we present an unusual lesion of the upper cervical spine treated nonoperatively with closed manual reduction under general anesthesia. To date, there is no available consensus for the management of these lesions.

Cervical vertebrae anomalies and cleft lip and palate: a systematic review and meta-analysis

OBJECTIVES

This study investigated the association of congenital cervical vertebrae anomalies (CVA) with the prevalence of cleft lip and palate (CLP) specifying the most frequent associations.

METHODS

A meta-analysis was based on the Preferred Reporting Items of Systematic reviews and Meta-Analyses guideline. A search of the PubMed, Embase, Web of Science, Science Direct, Scopus and Lilacs database was performed until March 2018. Clinical studies that evaluated CVA in individuals with CLP (experimental group) and without CLP (control group) was included. For the statistical analysis, the software Comprehensive Meta-Analysis (Biostat; Englewood, NJ) was used, with a p-value < 0.05 considered significant.

RESULTS

A total of 10 articles were included, for a total of 2566 individuals with CLP and 2301 individuals without CLP. The meta-analysis indicated statistically significant differences and the group of individuals with CLP had an increased number of CVA when compared to the group of individuals without CLP (p < 0.05; 95% confidence interval, 2.41-6.11; heterogeneity: Q-value 32.8, I2 72.6%).

CONCLUSIONS

This study indicated that CVA are associated with the presence of CLP. Among the patients with CVA the most frequent anomalies were the deficiency of the posterior arch, followed by the fusion of cervical vertebrae. Individuals with cleft palate and those with unilateral cleft lip and palateCLP had an increased prevalence of CVA.

Otolaryngologic Manifestations of Klippel-Feil Syndrome in Children

Importance

Children with Klippel-Feil syndrome (KFS), characterized principally by abnormal fusion of 2 or more cervical vertebrae, may have many additional congenital anomalies. The overall prevalence of otolaryngologic manifestations among patients with KFS has not been previously characterized.

Objective

To define the otolaryngologic diagnoses made and procedures performed in 95 patients with KFS, which, to our knowledge, is the largest series of this challenging patient population published to date.

Design, Setting, and Participants

For this retrospective review, all patients with KFS who underwent otolaryngology consultation at our institution over a 26-year period (January 1989 to December 2015) were included. Patients were identified using International Classification of Diseases, Ninth Revision (ICD-9) codes and were confirmed through individual medical record review. Relevant otolaryngologic diagnoses and procedures were extracted using ICD-9 and Current Procedural Terminology codes, respectively. Selected demographics included age, sex, number of clinic visits, and number of procedures.

Main Outcomes and Measures

The primary outcomes were the otolaryngologic diagnoses and procedures associated with the KFS patient population; the secondary outcome was Cormack-Lehane classification documented during airway procedures.

Results

Overall, 95 patients with KFS were included in this study (55 males [58%] and 40 females [42%]); mean (range) age at time of presentation to the otorhinolaryngology clinic was 5.8 (birth-23.0) years. Each patient with KFS averaged 8 visits to the otorhinolaryngology office and 5 otolaryngologic diagnoses. The most common diagnosis was conductive hearing loss (n = 49 [52%]), followed by sensorineural hearing loss (n = 38 [40%]), and dysphagia (n = 37 [39%]). Sixty-two (65%) patients underwent otolaryngologic procedures, with 44 (46%) undergoing multiple procedures. The most common procedure was tympanostomy tube placement (n = 36 [38%]), followed by office flexible endoscopy (n = 23 [24%]). Twelve of the 20 patients who underwent direct laryngoscopy had documented Cormack-Lehane classification; 5 of 12 patients (42%) had a compromised view (grade 2, 3, or 4) of the larynx. Three patients required tracheotomies at this institution for airway stabilization purposes; each had severe upper airway obstruction leading to respiratory failure.

Conclusions and Relevance

Patients with KFS require consultation for a variety of otolaryngologic conditions. Among these, hearing loss is the most common, but airway issues related to cervical spine fusion are the most challenging. Formulating an appropriate care plan in advance is paramount, even for routine otolaryngology procedures.

Demographics, presentation and symptoms of patients with Klippel-Feil syndrome: analysis of a global patient-reported registry

INTRODUCTION

Klippel-Feil syndrome (KFS) occurs due to failure of vertebral segmentation during development. Minimal research has been done to understand the prevalence of associated symptoms. Here, we report one of the largest collections of KFS patient data.

METHODS

Data were obtained from the CoRDS registry. Participants with cervical fusions were categorized into Type I, II, or III based on the Samartzis criteria. Symptoms and comorbidities were assessed against type and location of fusion.

RESULTS

Seventy-five patients (60F/14M/1 unknown) were identified and classified as: Type I, n = 21(28%); Type II, n = 15(20%); Type III, n = 39(52%). Cervical fusion by level were: OC-C1, n = 17(22.7%), C1-C2, n = 24(32%); C2-C3, n = 42(56%); C3-C4, n = 30(40%); C4-C5, n = 42(56%); C5-C6, n = 32(42.7%); C6-C7, n = 25(33.3%); C7-T1, n = 13(17.3%). 94.6% of patients reported current symptoms and the average age when symptoms began and worsened were 17.5 (± 13.4) and 27.6 (± 15.3), respectively. Patients reported to have a high number of comorbidities including spinal, neurological and others, a high frequency of general symptoms (e.g., fatigue, dizziness) and chronic symptoms (limited range of neck motion [LROM], neck/spine muscles soreness). Sprengel deformity was reported in 26.7%. Most patients reported having received medication and invasive/non-invasive procedures. Multilevel fusions (Samartzis II/III) were significantly associated with dizziness (p = 0.040), the presence of LROM (p = 0.022), and Sprengel deformity (p = 0.036).

CONCLUSION

KFS is associated with a number of musculoskeletal and neurological symptoms. Fusions are more prevalent toward the center of the cervical region, and less common at the occipital/thoracic junction. Associated comorbidities including Sprengel deformity may be more common in KFS patients with multilevel cervical fusions. These slides can be retrieved under Electronic Supplementary Material.

Morphological classification of the tubercle of insertion of the transverse atlantal ligament: A computer tomography-based anatomical study of 200 subjects

BACKGROUND AND PURPOSE

The atlantal tubercle is the attachment point of the transverse atlantal ligament, the main stabilizer of the atlantoaxial complex. No system of classification of the tubercle exists in the literature. We aimed to develop a morphologically based classification system of the atlantal tubercle to aid clinicians who deal with craniocervical pathology.

MATERIALS AND METHODS

A retrospective review of computed tomography (CT) scans of the cervical spine was performed. The morphology of the atlantal tubercle was classified into four variants: rounded (classical), pointed, flattened, and hypoplastic. Age, presence, and morphological type were recorded.

RESULTS

A total of 200 CT scans were identified and reviewed. The tubercle was present bilaterally in all patients. Patients were equally distributed over various age ranges. The following morphological types were recorded: rounded (227/400; 56.8%), pointed (13/400; 3.3%), flattened (126; 31.5%), and hypoplastic (34/400; 8.5%). The same type was seen bilaterally in 68% (135/200) of patients. Morphological types appear equally on the right and left side of the atlas.

CONCLUSIONS

The first morphologically based classification system of the atlantal tubercle utilizing CT is presented. Morphology type, especially hypoplastic type, may confer an increased risk for subsequent need for posterior fusion.

Cervical vertebral malformations in 9 dogs: radiological findings, treatment options and outcomes

BACKGROUND

Disregarding atlantoaxial instability in toy breed dogs associated with dens malformation and cervical spondylomyelopathy; cervical vertebral malformations are rare and poorly characterised in veterinary medicine and consequently treatment strategies and clinical outcome are sparsely documented.

RESULTS

Electronic clinical records at our veterinary referral hospital between April 2009 and November 2018 were searched for patients presented with cervical myelopathy secondary to an underlying suspected vertebral malformation/instability. Nine dogs met the inclusion criteria. Two dogs were diagnosed with atlantoaxial pseudoarthrosis, two dogs with a syndrome similar to Klippel-Feil in humans, two dogs with congenital cervical fusion, two dogs with congenital C2-C3 canal stenosis and deficiencies of the dorsal arch of the atlas and laminae of the axis and one with axial rotatory displacement. Tetraparesis, proprioceptive deficits, cervical hyperesthesia and cervical scoliosis were the most common clinical signs. The axis was the most commonly affected vertebrae (8/9 patients). Patients diagnosed with Klippel-Feil-like Syndrome were the younger (average of 262.5 days) and patients diagnosed with fused vertebrae the oldest (average of 2896 days) in our studied population (average of 1580.8 days).

CONCLUSION

Cervical vertebral malformations are rare, or alternatively, being underdiagnosed in veterinary medicine. Patients diagnosed with Klippel-Feil-like Syndrome had a successful medium and long-term outcome with conservative management. Surgical treatment was often indicated for the other conditions presented in this study due to spinal instability and/or myelopathy. Stabilisations via ventral approaches were revealed to be safe. Multicentre and prospective studies are necessary in veterinary medicine to better characterise clinical outcomes in cervical vertebral malformations.

Incidentalomas in Spine and Spinal Cord Imaging

Incidentalomas are common in magnetic resonance imaging (MRI) of the spine. These incidental findings (IFs) can be seen involving the spinal cord, nerve root, vertebral body, posterior arch and the extraspinal region. This review article describes the imaging findings, stratifies the IFs similar to the computed tomography (CT) colonography reporting and data system and briefly mentions the current recommendations for further evaluation and management of IFs. Radiologists are the first to detect these lesions, suggest further evaluation and management of IFs. It is therefore mandatory for them to be aware of recommendations in clinical practice in order to avoid increased patient anxiety, excessive healthcare expenditure and inadvertent therapeutic procedures.

Congenital Osseous Anomalies of the Cervical Spine: Occurrence, Morphological Characteristics, Embryological Basis and Clinical Significance: A Computed Tomography Based Study

Study Design

Observational retrospective computed tomography (CT) based study.

Purpose

To analyze the congenital anomalies of the cervical spine, their morphological variations and their clinical significance.

Overview of Literature

Studies published to date have focused mainly on upper cervical anomalies; no study has comprehensively reported on anomalies of both the occipitocervical and subaxial cervical spine.

Methods

Nine hundred and thirty cervical spine CT scans performed in Ganga Hospital, Coimbatore, India between January 2014 and November 2017 were screened by two independent observers to document anomalies of both the upper and lower cervical spine. CT scans conducted for infection, tumor, and/or deformity were excluded. Different morphological variations, embryological basis, and clinical significance of the anomalies were discussed.

Results

Of the 930 CT scans screened, 308 (33.1%) had congenital anomaly. Of these, 184 (59.7%) were males and 124 (40.2.7%) were females, with a mean age of 44.2 years (range, 14-78 years). A total of 377 anomalies were identified, with 69 cases (7.4%) having more than one anomaly. Two hundred and fifty (26.8%) anomalies of the upper cervical region (occiput to C2-C3 disk space) were identified, with the most common upper cervical anomalies being high-riding vertebral artery (108 cases, 11.6%) and ponticulus posticus (PP) (75 cases, 8%). One hundred and twenty seven (13.6%) anomalies of the lower cervical spine (C3-C7) were noted, of which double foramen transversarium was the most common anomaly observed in 46 cases (4.8%).

Conclusions

We found that 33.1% of CT scans had at least one congenital anomaly. Some anomalies, such as abnormal facet complex and arch anomalies, have to be differentiated from fractures in a trauma patient. Other anomalies, like PP, have to be looked for during preoperative planning to avoid complications during surgery. Therefore, knowledge of these anomalies is important as different anomalies have different clinical courses and management.

Prevalence of cervical vertebrae anomalies in patients with cleft lip and palate

Objective

To investigate the prevalence of cervical vertebral anomalies (CVA) in a group of patients presenting with cleft lip and palate (CLP) and to compare with a non-cleft population.

Material and methods

The sample comprised of 150 lateral cephalograms of non-syndromic patients with CLP and 150 non-cleft age-matched controls. The age range of both groups covered 6 to 20 years. An expert radiologist blinded to the cleft status evaluated the cephalograms for CVA and categorised them into normal, fusion, dehiscence and multiple cervical anomalies. The cleft group was subdivided according to the types of cleft (UCLP/ BCLP/ CPO) and gender (male/female). The CVA prevalence was compared between the cleft and non-cleft patients.

Results

The prevalence of CVA was 37.7% and 20.7% in cleft and non-cleft patients, respectively. The difference was statistically significant with a p-value <0.01. Of the types of clefts, a left UCLP had the highest prevalence of CVA (47.2%), with fusion (35.8%) most commonly seen. On comparing CLP with CPO, no significant variation was observed between the types of anomalies.

Conclusions

A high prevalence of CVA was observed in cleft patients compared with non-cleft subjects. The prevalence of CVA was similar between males and females. The practitioner should carefully evaluate the lateral cephalogram of CLP patients for CVA, which otherwise may remain undetected and lead to neurological symptoms later in life.

Radiological Evaluation of Craniocervical Region in Patients with Basilar Invagination

STUDY DESIGN

A retrospective analysis of collected data.

OBJECTIVE

Our study aims to present the morphology of cranial-cervical spinal canal in basilar invagination (BI) patients.

SUMMARY OF BACKGROUND DATA

BI is characterized by protrusion of the odontoid process into the foramen magnum (C0), leading to compression of the cervicomedullary junction. However, no study has ever clarified the anatomical diameters of spinal canal in patients with BI.

METHODS

The study retrospectively examined computed tomography (CT)-based anatomical characteristics in a cohort of 84 patients with and without BI. We measured the anteroposterior diameter (APD) and transversal diameter (TVD) of spinal canal from C0 to C4, together with the area of vertebral canal (Area). Independent samples t test was used for statistical analysis.

RESULTS

The APD in the BI group was shorter than the control group from C0 to C2 (C0: 27.98 vs. 35.11 mm, P < 0.001; C1: 11.87 vs. 16.91 mm, P < 0.001; C2: 12.91 vs. 14.84 mm, P < 0.001), but it became longer from C3 to C4. The TVD of the BI group was significantly wider from C0 to C3 (C0: 30.59 vs. 28.54 mm, P < 0.001; C1: 31.31 vs. 25.98 mm, P < 0.001; C2: 21.56 vs. 20.40 mm, P = 0.01; C3: 22.45 vs. 21.23 mm, P = 0.013), and it had no significance at C4. The Area showed no difference between the two groups from C1 to C2, but it turned larger at C3 and C4 in BI patients.

CONCLUSION

BI patients may have shorter APD from C0 to C2, which could be the leading cause of neurological compression, necessitating decompression on sagittal plane. Below the pathological levels, BI patients have larger spinal canal than general population.

LEVEL OF EVIDENCE

3.

Another Case of Multilevel Cervical Disconnection Syndrome Presenting as Neonatal Encephalopathy

Multilevel cervical disconnection syndrome (MCDS) is a rare malformation of the cervical spine previously documented in two toddlers. We present a case of a newborn first thought to have hypoxic-ischemic encephalopathy who was subsequently diagnosed with MCDS. The possibility of in utero presentation of the syndrome in this patient and the categorization of this syndrome in the spectrum of basilar skull/upper cervical malformation syndromes is discussed.

Conventional MRI

Conventional magnetic resonance imaging (MRI) allows for a detailed noninvasive visualization/examination of posterior fossa structures and represents a fundamental step in the diagnostic workup of many cerebellar disorders. In the first part of this chapter methodologic issues, like the correct choice of hardware (magnets, coils), pro and cons of the different MRI sequences, and patient management during the examination are discussed. In the second part, the MRI anatomy of the cerebellum, as noted on the various conventional MRI sequences, as well as a detailed description of cerebellar maturational processes from birth to childhood and into adulthood, are reported. Volumetric studies on the cerebellar growth based on three-dimensional MRI sequences are also presented. Moreover, we briefly discuss two main topics regarding conventional MRI of the cerebellum that have generated some debate in recent years: the differentiation between cerebellar atrophy, hypoplasia, and pontocerebellar hypoplasia, and signal changes of dentate nuclei after repetitive gadolinium-based contrast injections. The advantages and benefits of advanced neuroimaging techniques, including ¹H magnetic resonance spectroscopy, diffusion-weighted imaging, diffusion tensor imaging, and perfusion-weighted imaging are discussed in the last section of the chapter.

Malformed vertebrae: a clinical and imaging review

A variety of structural developmental anomalies affect the vertebral column. Malformed vertebrae can arise secondary to errors of vertebral formation, fusion and/or segmentation and developmental variation. Malformations can be simple with little or no clinical consequence, or complex with serious structural and neurologic implications. These anomalies can occasionally mimic acute trauma (bipartite atlas versus Jefferson fracture, butterfly vertebra versus burst fracture), or predispose the affected individual to myelopathy. Accurate imaging interpretation of vertebral malformations requires knowledge of ageappropriate normal, variant and abnormal vertebral morphology and the clinical implications of each entity. This knowledge will improve diagnostic confidence in acute situations and confounding clinical scenarios.

This review article seeks to familiarize the reader with the embryology, normal and variant anatomy of the vertebral column and the imaging appearance and clinical impact of the spectrum of vertebral malformations arising as a consequence of disordered embryological development.

Teaching points

• Some vertebral malformations predispose the affected individual to trauma or myelopathy.

• On imaging, malformed vertebrae can be indistinguishable from acute trauma.

• Abnormalities in spinal cord development may be associated and must be searched for.

• Accurate interpretation requires knowledge of normal, variant and abnormal vertebral morphology.

Cervical myelopathy caused by invaginated laminae of the axis associated with occipitalizaion of the atlas: Case report and literature review

RATIONALE

In previous studies, few cases of cervical myelopathy caused by invaginated anomalous laminae of the axis have been reported, and none of them was combined with occipitalization of the atlas.

PATIENT CONCERNS

A 28-year-old male was brought to our hospital with motor and sensory impairments of the extremities after a car accident.

DIAGNOSES

MRI showed the spinal cord was markedly compressed at the C2/3 level. Reconstructed CT scans revealed an invaginated laminae of axis into the spinal canal as well as atlas assimilation.

INTERVENTIONS

The patient was successfully managed with surgical treatment by removal of the anomalous osseous structure as well as fixation and fusion.

OUTCOMES

The patient had a rapid recovery after the operation. He regained the normal strength of his 4 extremities and the numbness of his extremities disappeared. He returned to his normal work 3 months after the surgery without any symptoms.

LESSONS

Invaginated laminae of axis combined with occipitalization of the atlas is a rare deformity. MRI and reconstructed CT scans are useful for both diagnosing and surgical planning of this case. Surgical removal of the laminae results in a satisfactory outcome. The pathogenesis of this anomaly could be the fusion sequence error of the 4 chondrification centers in the embryological term.

Cervical digit in a child: A case report

BACKGROUND

A "digit-like" bone is a rare developmental anomaly that is usually seen in the pelvic or thoracic regions. Such an anomaly in the cervical spine is extremely rare and few cases have been reported. We present a patient with an anomalous bone posterior to a cervical vertebra. The patient was admitted to our hospital with a gradually growing hard neck mass and esthetic complaints. Physical examination, radiographs, reconstructed computed tomography, and magnetic resonance imaging revealed a digit-like bone posterior to the cervical spine. The patient was diagnosed with a "cervical digit." Through a posterior midline approach, the anomalous bone was excised because of its gradually increasing size and esthetic complaints.

RESULTS

Intraoperatively, the bony mass was found to have a pseudoarticulation with the spinous process of C5 (the fifth cervical vertebra). The specimen consisted of normal bone and cartilage. The child returned to a normal life postoperatively with no symptoms. There was no recurrence at the 2-year follow-up.

CONCLUSION

A congenital cervical digit is a rare deformity. A detailed clinical workup and advanced imaging examinations are useful for diagnosing such conditions. Esthetic complaints contribute to surgical indications. This is the first cervical digit managed with surgical excision of the anomalous bone and had a favorable outcome.

Absent congenital cervical pedicle nearly misdiagnosed as a facet dislocation: A case report

Background

Cervical spinal injury encompasses up to 1.5% of all pediatric injuries. Children, and more specifically infants, are a difficult subset of patients to obtain neurological exam in the setting of trauma, thus necessitating the use of cervical X-rays, CT scans, and MRI imaging.

Case description

A healthy, 15-month-old boy had an unwitnessed fall down a flight of stairs and received a CT scan of the head and cervical spine in the emergency department due to cephalohematoma and mechanism of injury. The patient was initially diagnosed with a unilateral facet dislocation but after additional imaging and rigorous interdisciplinary discussions, the patient was correctly diagnosed with a congenitally absent left C5 pedicle. Surgical intervention was not pursued and the patient was discharged home with close follow up.

Conclusion

In the acute trauma setting, congenital absent cervical pedicle can be difficult to differentiate from unilateral facet dislocation and may require the use of advanced imaging and close communication between the neurosurgery and radiology departments. Given the high morbidity and mortality involved in the repair of facet dislocation in a child, it is crucial to maintain high degree of clinical suspicion for absent spinal pedicle. In this case, the patient nearly underwent surgical intervention, but was ultimately able to be discharged home with no symptoms or deficits after correct diagnosis.

Anatomic Variations of the Anterior Atlantodental Joint and Relations to the Apical and Alar Ligaments in a Geriatric Population

BACKGROUND

Degenerative changes in the upper cervical spine may be age related degeneration or a pathological process such as rheumatoid arthritis. However, to our knowledge, the relationship between the apical and alar ligaments and these anomalies has not been discussed. We present anatomical variations of the anterior atlantodental joint observed during cadaveric dissection of adult craniovertebral junctions, the relationship with the alar and apical ligaments and discuss possible origins and clinical implications.

METHODS

The upper cervical spine including part of the occiput was dissected from cadavers whose mean age at death was 78.9 years-old. The anterior atlantodental joint and apical and alar ligaments were observed and any atypical findings were noted.

RESULTS

In eleven specimens, seven had a dens corona, three had an os odontoideum and one had a dens aureola, which arose from the upper part of the anterior arch of the atlas. Only four specimens had an apical ligament.

CONCLUSIONS

The possible etiologies and the clinical applications of these craniovertebral anomalies in a geriatric population should be appreciated by the clinician treating patients with disease in this area or interpreting imaging in the region.

Cone beam computed tomography incidental findings of the cervical spine and clivus: retrospective analysis and review of the literature

OBJECTIVE

The aim of this study was to analyze and describe incidental findings in the cervical spine (C-spine) and the clivus encountered in cone beam computed tomography (CBCT) imaging. The wide range of possible anatomic variants and pathoses is discussed in the context of the medical and dental literature to clarify their radiographic appearance and clinical implications as a guide for the oral and maxillofacial radiologist.

STUDY DESIGN

A retrospective analysis of radiographic reports was conducted based on CBCT images from 2 oral and maxillofacial imaging centers. Reports documenting incidental findings in the C-spine or the clivus were selected. Data on patient age and sex were collected, and each incidental finding was categorized as degenerative, congenital, or developmental/pathologic. Each finding is discussed with clinical importance and is pictorially presented.

RESULTS

From a total of 7689 CBCT reports, there were 732 incidental findings (9.5%) in the C-spine or the clivus. Most findings were in the C-spine (92.3%), were degenerative in nature (78.7%), and occurred in females in their sixth decade. Logistic regression analysis showed that the odds of presenting with a degenerative incidental finding in the C-spine or the clivus did not differ based on sex but were 5.5 times (95% confidence interval, 3.77-8.04) higher if the patient was aged 50 years or older.

CONCLUSIONS

This review is the largest and the first to characterize incidental findings in the C-spine and the clivus. Such findings were reported in 9.5% of radiographic reports. Several presented as uncommon congenital variants that are not usually spotlighted during oral and maxillofacial radiology training.

Treatment of Basilar Invagination With Klippel-Feil Syndrome: Atlantoaxial Joint Distraction and Fixation With Transoral Atlantoaxial Reduction Plate

BACKGROUND

Klippel-Feil syndrome (KFS) is characterized by congenital vertebral fusion of the cervical spine and a wide spectrum of associated anomalies. In patients with KFS with basilar invagination (BI), compression of the brainstem and upper cervical cord results in neurological deficits, and decompression and occipitocervical reconstruction are required. The highly varied anatomy of KFS makes a posterior occipitocervical fixation strategy challenging. For these patients, the transoral atlantoaxial reduction plate (TARP) operation is an optimal option to perform a direct anterior fixation to achieve stabilization.

OBJECTIVE

To evaluate the effectiveness of TARP internal fixation for the treatment of BI with KFS.

METHODS

Ten consecutive patients with BI and KFS who underwent TARP reduction and fixation from 2010 to 2012 were reviewed. Clinical assessment and image measurements were performed preoperatively and at the most recent follow-up. Nine patients (9/10) were followed for an average of 31.44 months.

RESULTS

Symptoms were alleviated in 9 of 9 patients (100.00%). The odontoid process was ideally corrected with the TARP system. The mean clivus canal angle improved from 124° preoperatively to 152° postoperatively. The average preoperative and postoperative Japanese Orthopedic Association scores were 10.56 (n = 9) and 14.67 (n = 9), respectively, indicating 63.82% improvement. There was bony bridge catenation on the computed tomography scans and no evidence of hardware failure at 6 months.

CONCLUSION

The TARP operation is effective and safe for treating patients with BI with KFS. The midterm clinical results were satisfactory.