Cervical medullary syndrome secondary to craniocervical instability and ventral brainstem compression in hereditary hypermobility connective tissue disorders: 5-year follow-up after craniocervical reduction, fusion, and stabilization

Surgical Treatment of Basilar Invagination without Evident Atlantoaxial Instability (Type B) - A Systematic Review

Chiari 1 malformation (CM1) and Basilar Invagination (BI) are the most common congenital bone and neural disorders of the craniovertebral junction. There is still discussion in the literature regarding best treatment practices for Type B BI. This systematic review aims to evaluate the treatment options for symptomatic type B BI especially concerning the need for craniocervical fusion. We performed a systematic literature review, focusing on surgical studies of patients with type B BI that reported the surgical technique used and the clinical outcomes. The MINORS instrument was utilized for methodological quality assessment as well as the level of evidence (LOL) of the included studies. Six studies were included, two of which used similar patients' samples. Posterior fossa decompression (PFD) with or without duroplasty was employed in three studies, C1-2 fusion in one, and C1-2 distraction and fusion in two studies. All reported patients' improvement post-surgery regardless of the technique used. Failure of PFD was associated with bone segmental anomalies in one study, and early deaths were associated with C1-2 fusion. The quality of the included studies was acceptable, with four studies at LOL 4 and two studies at LOL 3. There are varying surgical treatments for type B BI. PFD (most often with duroplasty) is safe and effective for patients without ventral compression. Some authors recommended C1-2 stabilization in all cases, and reported clinical improvement. Until prospective comparative studies, the ideal treatment option for type B BI remains unclear.

Halo traction evaluation of craniocervical instability in hereditary connective tissue disorder patients: Case series

INTRODUCTION

Craniocervical instability (CCI) is a condition commonly found in patients with connective tissue disorders such as Ehlers-Danlos Syndrome (EDS), leading to various symptoms. Assessing patients for surgical fusion as a treatment for CCI is challenging due to the complex nature of EDS-related symptoms. This study aimed to evaluate the role of pre-fusion halo-vest traction in alleviating symptoms and determining suitable candidates for fusion surgeries.

METHODS

EDS patients (n = 21) with neurological symptoms underwent insertion of halo-vest traction between 2019 and 2024. Patients completed a CCI Questionnaire before and after the halo-vest traction, reporting symptoms related to headache, vision, hearing, equilibrium, and function. Symptom groups were assigned scores based on patient responses, with one point for each affirmative answer. Before and after scores were analyzed using paired Student's t-test. Patients experiencing over 50 % improvement in the majority of symptoms were considered for definitive fusion surgery. 16 out of 21 patients subsequently underwent fusion for CCI.

RESULTS

The average age of the patients was 35 years, with a female-to-male ratio of 20:1, consistent with existing literature. Significant improvements were observed in various symptom groups after halo-vest traction, including headache (57 % improvement, p < 0.001), brainstem functions (71 % improvement, p < 0.001), cerebellar functions (55 % improvement, p < 0.001), hearing (63 % improvement, p < 0.001), motor functions (51 % improvement,p < 0.001), vision (60 % improvement, p < 0.001), cardiovascular functions (46 % improvement, p < 0.05), sensory and pain (53 % improvement, p < 0.001), high cortical functions (54 % improvement, p < 0.001), GI functions (52 % improvement, p < 0.05), bladder functions (52 % improvement, p < 0.05), and Modified Karnofsky score (30 % improvement, p < 0.05).

CONCLUSION

Halo-vest traction proved to be a simple and effective method for evaluating patients for surgery while providing symptomatic relief in EDS-related CCI cases. It allows surgeons to monitor patients with a now post halo stable craniocervical junctions (CCJ) before committing to surgery.

Comorbidities and neurosurgical interventions in a cohort with connective tissue disorders

Background

Connective tissue disorders (CTDs) are a heterogeneous group of disorders often presenting with a variety of comorbidities including musculoskeletal, autonomic, and immune dysfunction. Some CTDs such as hypermobile Ehlers-Danlos syndrome (hEDS), which is one of the most common, have been associated with neurological disorders requiring surgical intervention. The frequency of these comorbidities in these populations and their subsequent requirement for neurosurgical intervention remains unclear.

Methods

Based on our initial experience with this population, we investigated the presentation rates of specific comorbidities and neurosurgical interventions in a cohort of individuals referred to our institution for evaluation and neurosurgical management of issues secondary to diagnosed or suspected CTDs from 2014 to 2023. Primary diagnoses were made by referring physicians or institutions based on clinical presentation and standard-of-care criteria. We evaluated relationships between diagnoses and surgical interventions by multivariate correlation and intersection plots using the UpSetR package.

Results

Of 759 individuals, we excluded 42 based on incomplete data. From the remaining (total cohort, N = 717), 460 (64%) individuals were diagnosed with hEDS, 7 were diagnosed with a CTD other than hEDS, and 250 lacked a formal CTD diagnosis. We found that individuals with hEDS had a higher frequency of certain comorbidities, such as Mast Cell Activation Disorder and Postural Orthostatic Tachycardia Syndrome, and neurosurgical intervention compared to individuals without a CTD diagnosis (unaffected). Of the total cohort, 426 (59%) were diagnosed with Chiari I Malformation, which shared a significant overlap with hEDS. Of those who elected to undergo surgery (n = 612), 61% required craniocervical fusion (CCF). Notably, of the 460 individuals diagnosed with hEDS, 404 chose surgical intervention, of which, 73% required CCF for craniocervical instability.

Conclusion

In this retrospective study of individuals referred to our institution for evaluation of CTDs potentially requiring neurosurgical intervention, we defined the frequency of presentation of specific comorbidities that we commonly encountered and revealed the rate at which they required neurosurgical intervention.

Headache disorders in patients with Ehlers-Danlos syndromes and hypermobility spectrum disorders

Extra-articular symptoms, including headaches, are frequently encountered in patients with Ehlers-Danlos syndrome (EDS) and hypermobility spectrum disorders (HSD), and may be the presenting complaint. Migraine is reported in up to three quarters of patients with symptomatic joint hypermobility, have a higher headache frequency, and an earlier age of onset compared to the general population. Orthostatic headache is an important presentation, and should raise suspicion of an underlying spinal cerebrospinal fluid leak, dysautonomia, and craniocervical pathology, which are all associated with heritable connective tissue disorders (HCTD) including EDS. Any proposed invasive procedure should be scrupulously balanced against its potential risks, taking into account the type of EDS (e.g., vascular EDS) and its systemic manifestations. This is particularly pertinent when suspecting craniocervical instability since it remains a controversial diagnosis with a limited treatment evidence-base. This article reviews the commonly encountered headache disorders in patients with joint hypermobility-related conditions with a focus on EDS and HSD, describes their diverse presentations, and an overview of the recommended management strategies. It also emphasises the need for increased awareness of comorbid conditions in EDS and HSD among clinicians treating headaches to ensure a patient-tailored approach and facilitate a multidisciplinary approach in managing often complex cases.

Radiographic Indicators of Craniocervical Instability: Analyzing Variance of Normative Supine and Upright Imaging in a Healthy Population

STUDY DESIGN

Single-institution retrospective review.

OBJECTIVE

To establish baseline ranges and variability of 7 radiographic measurements of the cervical spine in a healthy patient population as potential diagnostic tools for craniocervical instability.

SUMMARY OF BACKGROUND DATA

Craniocervical instability, common in patients with connective tissue disease such as Ehlers-Danlos Syndrome, often presents with a wide range of symptoms, including neck pain. Current diagnostic methods employ a range of clinical and radiographic features, but diagnostic challenges remain due to missed indications on static imaging and a lack of standardized measurement values and normalized variance.

METHODS

Seventy-two healthy patients with cervical imaging were analyzed. Surgimap software was used to annotate supine computed tomography images, flexion, extension, and neutral x-ray images for measurement. These measurements included the atlanto-dental interval, clival-axial angle, basion-dens interval, basion-axis interval, perpendicular basion to the inferior aspect of C2, also known as Grabb Oakes measurement, and the hard palate to C1 and hard palate to C2. Statistical analysis assessed differences among imaging modalities, and coefficients of variation were calculated for each measurement.

RESULTS

Our cohort consisted of a total of 72 patients with a mean age of 64 (SD: 13.54). All measurements except for the basion-axial interval and atlanto-dental interval demonstrated a significant difference between extension and flexion x-ray measurements. clivo-axial angle, hard palate to C1, and hard palate to C2 demonstrated the lowest coefficients of variance across imaging modalities.

CONCLUSION

Understanding normal variance in cervical measurements is invaluable for accurate CCI diagnosis. Using a cohort of healthy patients, this study delineates the distribution and spread of 7 cervical measurements, delineating reference values and variability in these key measurements and highlighting their potential for use as imaging markers for CCI.

LEVEL OF EVIDENCE

Level III.

Differentiating the Structural and Functional Instability of the Craniocervical Junction

This paper presents the anatomical and biomechanical aspects of chronic instability of the craniocervical junction (CCJ) with a discussion on clinical diagnostics based on mobility tests and provocative tests related to ligamentous system injuries, as well as radiological criteria for CCJ instability. In addition to the structural instability of the CCJ, the hypothesis of its functional form resulting from cervical proprioceptive system (CPS) damage is discussed. Clinical and neurophysiological studies have shown that functional disorders or organic changes in the CPS cause symptoms similar to those of vestibular system diseases: dizziness, nystagmus, and balance disorders. The underlying cause of the functional form of CCJ instability may be the increased activity of mechanoreceptors, leading to "informational noise" which causes vestibular system disorientation. Due to the disharmony of mutual stimulation and the inhibition of impulses between the centers controlling eye movements, the cerebellum, spinal motoneurons, and the vestibular system, inadequate vestibulospinal and vestibulo-ocular reactions occur, manifesting as postural instability, dizziness, and nystagmus. The hyperactivity of craniocervical mechanoreceptors also leads to disturbances in the reflex regulation of postural muscle tone, manifesting as "general instability". Understanding this form of CCJ instability as a distinct clinical entity is important both diagnostically and therapeutically as it requires different management strategies compared to true instability. Chronic CCJ instability significantly impacts the quality of life (QOL) of affected patients, contributing to chronic pain, psychological distress, and functional impairments. Addressing both structural and functional instability is essential for improving patient outcomes and enhancing their overall QOL.

Co-occurrence of tethered cord syndrome and cervical spine instability in hypermobile Ehlers-Danlos syndrome

The Ehlers-Danlos Syndromes (EDS) represent a group of hereditary connective tissue disorders, with the hypermobile subtype (hEDS) being the most prevalent. hEDS manifests with a diverse array of clinical symptoms and associated comorbidities spanning the musculoskeletal, neurological, gastrointestinal, cardiovascular, and immunological systems. hEDS patients may experience spinal neurological complications, including cervico-medullary symptoms arising from cranio-cervical and/or cervical instability/hypermobility, as well as tethered cord syndrome (TCS). TCS is often radiographically occult in nature, not always detectable on standard imaging and presents with lower back pain, balance issues, weakness in the lower extremities, sensory loss, and bowel or bladder dysfunction. Cervical instability due to ligament laxity can lead to headaches, vertigo, tinnitus, vision changes, syncope, radiculopathy, pain, and dysphagia. TCS and cervical instability not only share clinical features but can also co-occur in hEDS patients, posing challenges in diagnostics and clinical management. We present a review of the literature and a case study of a 20-year-old female with hEDS, who underwent surgical interventions for these conditions, highlighting the challenges in diagnosing and managing these complexities and underscoring the importance of tailored treatment strategies to improve patient outcomes.

Comprehensive Physiotherapeutic Management of Atlas Occipitalization: A Case Report

The atlas (C1) and occipital bone at the base of the skull fuse together in atlas occipitalization, an uncommon congenital abnormality. Because it can result in cervical spine instability, nerve impingement, and related symptoms including stiffness, pain, and neurological impairments, it poses a challenging therapeutic problem. We describe the case of a female patient, 27 years old, who had gradually deteriorating neck discomfort, stiffness, and limited cervical mobility for six years prior to presentation. Her symptoms worsened over time despite conservative treatment, so more testing was necessary. Atlas occipitalization, congenital fusion at the C7 and D1 vertebrae, and other related cervical spine pathologies were identified by imaging examinations. The intricacies of atlas occipitalization and related cervical spine pathologies are highlighted in this case study, along with the diagnostic difficulties and interdisciplinary therapeutic strategy needed to address them. To improve cervical range of motion (ROM), lessen discomfort, and improve functional results, the patient underwent a thorough musculoskeletal examination and was given a customized physiotherapeutic intervention.

Craniocervical instability in patients with Ehlers-Danlos syndromes: outcomes analysis following occipito-cervical fusion

Craniocervical instability (CCI) is increasingly recognized in hereditary disorders of connective tissue and in some patients following suboccipital decompression for Chiari malformation (CMI) or low-lying cerebellar tonsils (LLCT). CCI is characterized by severe headache and neck pain, cervical medullary syndrome, lower cranial nerve deficits, myelopathy, and radiological metrics, for which occipital cervical fusion (OCF) has been advocated. We conducted a retrospective analysis of patients with CCI and Ehlers-Danlos syndrome (EDS) to determine whether the surgical outcomes supported the criteria by which patients were selected for OCF. Fifty-three consecutive subjects diagnosed with EDS, who presented with severe head and neck pain, lower cranial nerve deficits, cervical medullary syndrome, myelopathy, and radiologic findings of CCI, underwent open reduction, stabilization, and OCF. Thirty-two of these patients underwent suboccipital decompression for obstruction of cerebral spinal fluid flow. Questionnaire data and clinical findings were abstracted by a research nurse. Follow-up questionnaires were administered at 5-28 months (mean 15.1). The study group demonstrated significant improvement in headache and neck pain (p < 0.001), decreased use of pain medication (p < 0.0001), and improved Karnofsky Performance Status score (p < 0.001). Statistically significant improvement was also demonstrated for nausea, syncope (p < 0.001), speech difficulties, concentration, vertigo, dizziness, numbness, arm weakness, and fatigue (p = 0.001). The mental fatigue score and orthostatic grading score were improved (p < 0.01). There was no difference in pain improvement between patients with CMI/LLCT and those without. This outcomes analysis of patients with disabling CCI in the setting of EDS demonstrated significant benefits of OCF. The results support the reasonableness of the selection criteria for OCF. We advocate for a multi-center, prospective clinical trial of OCF in this population.

Complication Avoidance in Chiari Malformation Surgery

Posterior fossa decompression for symptomatic Chiari malformation is an effective and frequently performed procedure, but it does carry risks of significant complications including cerebrospinal fluid leak and craniocervical instability. Patients sometimes do not improve or worsen after decompression, which may discourage neurosurgeons from performing Chiari decompression surgery. In this chapter, management strategies and surgical approaches are discussed that minimize the risks of complications and maximize favorable outcomes in Chiari malformation surgery.

Intraoperative occipital to C2 angle and external acoustic meatus-to-axis angular measurements for optimizing alignment during posterior fossa decompression and occipitocervical fusion for complex Chiari malformation

Background

Excess flexion or extension during occipitocervical fusion (OCF) can lead to postoperative complications, such as dysphagia, respiratory problems, line of sight issues, and neck pain, but posterior fossa decompression (PFD) and OCF require different positions that require intraoperative manipulation.

Objective

The objective of this study was to describe quantitative fluoroscopic morphometrics in Chiari malformation (CM) patients with symptoms of craniocervical instability (CCI) and demonstrate the intraoperative application of these measurements to achieve neutral craniocervical alignment while leveraging a single axis of motion with the Mayfield head clamp locking mechanism.

Methods

A retrospective cohort study of patients with CM 1 and 1.5 and features of CCI who underwent PFD and OCF at a single-center institution from March 2015 to October 2020 was performed. Patient demographics, preoperative presentation, radiographic morphometrics, operative details, complications, and clinical outcomes were analyzed.

Results

A total of 39 patients met the inclusion criteria, of which 37 patients (94.9%) did not require additional revision surgery after PFD and OCF. In this nonrevision cohort, preoperative to postoperative occipital to C2 angle (O-C2a) (13.5° ± 10.4° vs. 17.5° ± 10.1°, P = 0.047) and narrowest oropharyngeal airway space (nPAS) (10.9 ± 3.4 mm vs. 13.1 ± 4.8 mm, P = 0.007) increased significantly. These measurements were decreased in the two patients who required revision surgery due to postoperative dysphagia (mean difference - 16.6°° in O C2a and 12.8°° in occipital and external acoustic meatus to axis angle). Based on these results, these fluoroscopic morphometrics are intraoperatively assessed, utilizing a locking Mayfield head clamp repositioning maneuver to optimize craniocervical alignment prior to rod placement from the occipital plate to cervical screws.

Conclusion

Establishing a preoperative baseline of reliable fluoroscopic morphometrics can guide surgeons intraoperatively in appropriate patient realignment during combined PFD and OCF, and may prevent postoperative complications.

Cervical Spine Instability Screening Tool Thai Version: Assessment of Convergent Validity and Rater Reliability

Neck pain, dizziness, difficulty supporting the head for an extended period, and impaired movement are all symptoms of cervical spine instability, which may produce cervical spondylolisthesis in patients who have more severe symptoms. To avoid problems and consequences, early detection of cervical spine instability is required. A previous study created a Thai-language version of a cervical spine instability screening tool, named the CSI-TH, and evaluated its content validity. However, other characteristics of the CSI-TH still needed to be evaluated. The objective of the current study was to assess the rater reliability and convergent validity of the CSI-TH. A total of 160 participants with nonspecific chronic neck pain were included in the study. The Neck Disability Index Thai version (NDI-TH), the Visual Analog Scale Thai version (VAS-TH), and the Modified STarT Back Screening Tool Thai version (mSBST-TH) were used to evaluate the convergent validity of the CSI-TH. To determine inter- and intra-rater reliabilities, novice and experienced physical therapists were involved. The results showed that rater reliabilities were excellent: the intra-rater reliability was 0.992 (95% CI = 0.989 ± 0.994), and the inter-rater reliability was 0.987 (95% CI = 0.983 ± 0.991). The convergent validities of the VAS-TH, NDI-TH, and mSBST-TH when compared with the CSI-TH were 0.5446, 0.5545, and 0.5136, respectively (p < 0.01). The CSI-TH was developed for use by physical therapists and is reliable. It can be used by physical therapists, whether they are experienced or novices, and has an acceptable correlation to other neck-related questionnaires. The CSI-TH is concise, suitable for clinical use, and lower-priced when compared to the gold standard in diagnosis for patients with cervical spine instability.

Perioperative opioid-minimization approach as a useful protocol in the management of patients with Ehlers-Danlos syndrome-hypermobility type, craniocervical instability and severe chronic pain who are to undergo occipito-cervical fixation

Patients suffering from connective tissue disorders like Ehlers-Danlos syndrome hypermobility type/joint hypermobility syndrome (EDS-HT/JHS) may be affected by craniocervical instability (CCI). These patients experience myalgic encephalomyelitis, chronic fatigue, depression, extreme occipital-cervical pain, and severe widespread pain that is difficult to relieve with opioids. This complex and painful condition can be explained by the development of chronic neuroinflammation, opioid-induced hyperalgesia, and central sensitization. Given the challenges in treating such severe physical pain, we evaluated all the analgesic methods previously used in the perioperative setting, and updated information was presented. It covers important physiopathological aspects for the perioperative care of patients with EDS-HT/JHS and CCI undergoing occipital-cervical/thoracic fixation/fusion. Moreover, a change of paradigm from the current opioid-based management of anesthesia/analgesia in these patients to the perioperative opioid minimization strategies used by the authors was analyzed and proposed as follow-up considerations from our previous case series. These strategies are based on total-intravenous opioid-free anesthesia, multimodal analgesia, and a postoperative combination of anti-hyperalgesic coadjuvants (lidocaine, ketamine, and dexmedetomidine) with an opioid-sparing effect.

Craniovertebral Junction Instability after Oncological Resection: A Narrative Review

The craniovertebral junction (CVJ) is a complex transition area between the skull and cervical spine. Pathologies such as chordoma, chondrosarcoma and aneurysmal bone cysts may be encountered in this anatomical area and may predispose individuals to joint instability. An adequate clinical and radiological assessment is mandatory to predict any postoperative instability and the need for fixation. There is no common consensus on the need for, timing and setting of craniovertebral fixation techniques after a craniovertebral oncological surgery. The aim of the present review is to summarize the anatomy, biomechanics and pathology of the craniovertebral junction and to describe the available surgical approaches to and considerations of joint instability after craniovertebral tumor resections. Although a one-size-fits-all approach cannot encompass the extremely challenging pathologies encountered in the CVJ area, including the possible mechanical instability that is a consequence of oncological resections, the optimal surgical strategy (anterior vs posterior vs posterolateral) tailored to the patient's needs can be assessed preoperatively in many instances. Preserving the intrinsic and extrinsic ligaments, principally the transverse ligament, and the bony structures, namely the C1 anterior arch and occipital condyle, ensures spinal stability in most of the cases. Conversely, in situations that require the removal of those structures, or in cases where they are disrupted by the tumor, a thorough clinical and radiological assessment is needed to timely detect any instability and to plan a surgical stabilization procedure. We hope that this review will help shed light on the current evidence and pave the way for future studies on this topic.

Chiari I malformation management in patients with heritable connective tissue disorders

Background

Chiari malformation type I (CMI) is relatively common neurosurgical condition typically treated with posterior fossa decompression. However, the management of CMI in patients with heritable connective tissue disorders (CTDs), such as Ehlers-Danlos Syndrome, Marfan Syndrome, or Osteogenesis Imperfecta, involves a unique set of perioperative challenges.

Objective

This study aims to define the demographic information, comorbidities, and perioperative course of patients with concomitant CMI and CTD.

Methods

Patients with CMI admitted for surgical decompression from 2008 to 2015 were captured using the National Inpatient Sample (NIS). Information was collected based on ICD-9 codes. Descriptive and regression analyses were performed in SPSS (version 26).

Results

38,169 CMI patients, 353 of whom had CTD (0.92%), were identified. CMI patients with CTD were more likely to be female (p < 0.001) and present during teenage (p = 0.033) or young adult years (p < 0.001). They had more chronic issues (p < 0.001): systemic comorbidities include postural orthostatic tachycardia syndrome, cardiac dysrhythmias, and gastroparesis (all p < 0.001). CNS comorbidities include migraine, tethered spinal cord, and epilepsy (all p < 0.001). They have increased joint instability (both p < 0.001), as well as craniocervical instability (CCI). More posterior cervical fusion surgeries and application of cervical halo devices were seen during the same inpatient stay (both p < 0.001).

Conclusions

Patients with concurrent CTD and CMI were more likely to present with complex Chiari and associated CCI. They were also younger, more often female, and had more systemic, CNS, and joint abnormalities. As such, preoperative recognition of an underlying CTD is imperative to achieve optimal outcomes in this patient population.

Reference values of four measures of craniocervical stability using upright dynamic magnetic resonance imaging

PURPOSE

To establish reference ranges for four most commonly used diagnostic measures of craniocervical instability (CCI) in three cervical sagittal positions. This necessitated development of a reliable measurement protocol using upright, dynamic MRI (udMRI), to determine differences in the extent of motion between positions, and whether age and sex correlate with these measures.

MATERIALS AND METHODS

Deidentified udMRIs of 50 adults, referred for reasons other than CCI, were captured at three positions (maximal flexion, maximal extension and neutral). Images were analyzed, providing measures of basion-axial interval, basion-axial angle, basion-dens interval (BDI) and the Grabb-Oakes line (GOL) for all three positions (12 measures per participant). All measures were independently recorded by a radiologist and neurosurgeon to determine their reliability. Descriptive statistics, correlations, paired and independent t-tests were used. Mean (± 2 SD) identified the reference range for all four measures at each craniocervical position.

RESULTS

The revised measurement protocol produced inter-rater reliability indices of 0.69-0.97 (moderate-excellent). Fifty adults' (50% male; mean age 41.2 years (± 9.7)) reference ranges for all twelve measures were reported. Except for the BDI and GOL when moving between neutral and full flexion, significant extents of movement were identified between the three craniocervical positions for all four measures (p ≤ 0.005). Only a minor effect of age was found.

CONCLUSIONS

This is the first study to provide a rigorous standardized protocol for four diagnostic measures of CCI. Reference ranges are established at mid and ends of sagittal cervical range corresponding to where exacerbations of signs and symptoms are commonly reported.

Presentation and physical therapy management of upper cervical instability in patients with symptomatic generalized joint hypermobility: International expert consensus recommendations

Experts in symptomatic generalized joint hypermobility (S-GJH) agree that upper cervical instability (UCI) needs to be better recognized in S-GJH, which commonly presents in the clinic as generalized hypermobility spectrum disorder and hypermobile Ehlers-Danlos syndrome. While mild UCI may be common, it can still be impactful; though considerably less common, severe UCI can potentially be debilitating. UCI includes both atlanto-occipital and atlantoaxial instability. In the absence of research or published literature describing validated tests or prediction rules, it is not clear what signs and symptoms are most important for diagnosis of UCI. Similarly, healthcare providers lack agreed-upon ways to screen and classify different types or severity of UCI and how to manage UCI in this population. Consequently, recognition and management of UCI in this population has likely been inconsistent and not based on the knowledge and skills of the most experienced clinicians. The current work represents efforts of an international team of physical/physiotherapy clinicians and a S-GJH expert rheumatologist to develop expert consensus recommendations for screening, assessing, and managing patients with UCI associated with S-GJH. Hopefully these recommendations can improve overall recognition and care for this population by combining expertise from physical/physiotherapy clinicians and researchers spanning three continents. These recommendations may also stimulate more research into recognition and conservative care for this complex condition.

Spinal manifestations of Ehlers-Danlos syndrome: a scoping review

OBJECTIVE

Since its initial description, the definition of Ehlers-Danlos syndrome (EDS) has notably changed. At present, it broadly refers to disorders of the connective tissue that are heritable and have similar features including joint hypermobility, dermal dysplasia, and vascular as well as internal organ fragility. There has been no comprehensive review of spinal manifestations of EDS in the recent literature. That has led to controversies in management protocols of this so-called orphan disease.

METHODS

The authors used the latest version of the EDS classification from 2017, in which 13 subtypes were recognized. EDS has 19 different causal genes, mainly associated with collagen synthesis. Of these, 5 subtypes have associated spinal manifestations.

RESULTS

Some of the spinal pathologies associated with EDS include Chiari malformation, craniocervical instability, kyphoscoliosis, segmental instability and kyphosis, spontaneous CSF leaks, Tarlov cyst syndrome, tethered cord, and problems associated with wound healing. Here, the authors briefly discuss the demographics, etiology, pathophysiology, clinical features, management strategies, and directions for further research for each of these manifestations.

CONCLUSIONS

EDS belongs to the group of orphan diseases, with the total patient population being below 200,000. Further research on spinal manifestations of EDS is the need of the hour to establish clinical practice guidelines and close the significant knowledge gaps that currently exist.

Craniocervical instability in patients with Ehlers-Danlos syndrome: controversies in diagnosis and management

Ehlers-Danlos syndrome (EDS) is a rare hereditary condition that can result in ligamentous laxity and hypermobility of the cervical spine. A subset of patients can develop clinical instability of the craniocervical junction associated with pain and neurological dysfunction, potentially warranting treatment with occipitocervical fixation (OCF). Surgical decision-making in patients with EDS can be complicated by difficulty distinguishing from hypermobility inherent in the disease and true pathological instability necessitating intervention. Here we comprehensively review the available medical literature to critically appraise the evidence behind various proposed definitions of instability in the EDS population, and summarize the available outcomes data after OCF. Several radiographic parameters have been used, including the clivo-axial angle, basion-axial interval, and pB-C2 measurement. Despite increasing recognition of EDS by spine surgeons, there remains a paucity of data supporting proposed radiographic parameters for spinal instability among EDS patients. Furthermore, there is a lack of high-quality evidence concerning the efficacy of surgical treatments for chronic debilitating pain prevalent in this population. More standardized clinical measures and rigorous study methodologies are needed to elucidate the role of surgical intervention in this complex patient population.

Craniocervical Instability in Ehlers-Danlos Syndrome-A Systematic Review of Diagnostic and Surgical Treatment Criteria

STUDY DESIGN

Systematic review.

OBJECTIVE

Ehlers-Danlos Syndrome (EDS) comprises a spectrum of connective tissue disorders, which may be associated with cranio-cervical instability (CCI). There is a lack of consensus on diagnostic imaging parameters, indications, and outcomes of surgical treatment.

METHODS

This systematic review analyses the literature on diagnostic methods and/or criteria for CCI, screening the databases Ovid Medline, Embase, Cochrane Library, and PubMed. Articles were included based on the PRISMA guidelines and assessed using the Newcastle-Ottawa Quality Assessment Scale (NOS) and according to their evidence level.

RESULTS

Sixteen articles, including 78 surgical patients, met the inclusion criteria. The main diagnostic measures for CCI were dynamic x-rays and CT imaging. Ten different radiographic parameters were reported, of which 4 were the most frequently applied for surgical decision-making: the clivo-axial angle (CXA), the Harris measurement, the Grabb-Mapstone-Oakes measurement, and the angular displacement of C1 to C2. The evidence level ranged between III and V and the article quality between 4 and 8 out of 9 stars on the NOS Scale.

CONCLUSIONS

There is a lack of high quality, prospective evidence regarding the evaluation of suspected CCI in patients with EDS. Based on our systematic review, we recommend that the CXA, Harris measurement, Grabb-Mapstone-Oakes measurement, and the angular displacement of C1 to C2 be used to evaluate suspected CCI in EDS patients. Surgical fixation of suspected CCI should only be performed in cases with clear radiographic presence of instability and concordant symptoms/signs. Consensus-based guidelines and care pathways are required.

The Significance of Pain Drawing as a Screening Tool for Cervicogenic Headache and Associated Symptoms in Chronic Fatigue

Purpose

Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) present with a broad spectrum of symptoms, including headache. A simple, yet powerful tool – the pain drawing identifies essential aspects such as pain distribution. The aim with this study was to 1) evaluate the significance of pain drawing as a screening tool for cervicogenic headache using a predefined C2 pain pattern, 2) assess whether there was an association between dizziness/imbalance and a C2 pain pattern, and 3) compare subgroups according to the pain drawing with respect to pain characteristics and quality of life.

Patients and Methods

Pain drawings and clinical data from 275 patients investigated for ME/CFS were stratified into: 1) cervicogenic headache as determined by a C2 pain pattern, 2) headache with no C2 pain pattern, and 3) no headache. For inference logistic regression presented with odds ratios (OR) and 95% confidence intervals (95% CI) and Kruskal–Wallis test were applied.

Results

One hundred sixteen participants (42%) were stratified to the group for which the pain drawing corresponded to the C2 pain pattern, thus indicating putative cervicogenic origin of the headache. Dizziness/imbalance was strongly associated with a C2 pain pattern; OR 6.50 ([95% CI 2.42–17.40] p ˂ 0.00), whereas this association was non-significant for patients with headache and no C2 pain pattern. Those demonstrating a C2 pain pattern reported significantly higher pain intensity (p = 0.00) and greater pain extent (p = 0.00) than the other groups, and lower health-related quality of life (p = 0.00) than the group with no headache.

Conclusion

For patients with chronic fatigue who present with a C2 pain pattern (interpreted as cervicogenic headache) the pain drawing seems applicable as a screening tool for signs associated with neuropathic and more severe pain, dizziness and reduced quality of life as detection of these symptoms is essential for targeted treatment.

Craniocervical Stabilization After Failed Chiari Decompression: A Case Series of a Population with High Prevalence of Ehlers-Danlos Syndrome

BACKGROUND

In the treatment of Chiari malformation type I (CM-I), posterior fossa decompression is achieved via suboccipital craniectomy (SOC); however, some patients continue to experience symptoms after treatment, which may be due to craniocervical instability (CCI). The purposes of this study were to analyze data from patients who required an occipitocervical fusion (OCF) for the management of CCI after having previously undergone SOC for CM-I to determine if OCF is a safe and effective option and to determine any identifiable risk factors for CCI in these patients.

METHODS

A retrospective review was done on all patients who underwent an OCF performed by the senior author between November 2013 and June 2020 after having previously undergone SOC for CM-I. Demographic, radiographic, perioperative, and outcome data were collected and clivoaxial angles (CXAs) were measured pre- and postoperatively.

RESULTS

Fifteen patients were identified who developed symptomatic CCI after previously undergoing a suboccipital craniectomy for the treatment of CM-I. All 15 patients were treated by OCF with good outcome. Of these, 12 patients had a known diagnosis of Ehlers-Danlos syndrome (EDS). Overall, the CXAs of these patients were found to be corrected to a more anatomical alignment.

CONCLUSIONS

Symptomatic CCI should be recognized as a delayed postoperative complication in the surgical treatment of CM-I, with an underlying connective tissue hypermobility disorder such as EDS serving as a potential risk factor its development. CCI can be managed with OCF as a safe and effective treatment option for this patient population.

Relevance of C1/2 facet configurations and clivus-canal-angles for adult patients with Chiari I malformation with and without basilar invagination

OBJECTIVE

C1/2 facet configurations and clivus-canal angles (CXA) have been proposed as criteria for posterior fusion in Chiari I malformation (CMI).

METHODS

340 adults with CMI without basilar invagination (BI), 111 with CMI with BI and 100 age and sex matched controls were studied using sagittal T2-weighted MRI scans analyzing pre- and postoperative values with their impact on progression-free survival rates.

RESULTS

For CMI without BI, C1/2 facet configurations and CXA were similar to controls (142+11° and 144+10°, respectively) with low rates for posterior C1 displacements (7.1% and 10%, respectively). In CMI with BI, C1 facet displacements were common (54.9%) with lower CXA (120+15°). After foramen magnum decompression (FMD) in CMI without BI (n = 169), 1.8% developed posterior C1 facet displacements without CXA changes and a 97% progression-free survival rate for 10 years. In CMI with BI, patients without ventral compression or instability underwent FMD without fusion (n = 19). 5.3% developed a posterior C1 facet displacement without CXA changes and a 94% progression-free survival rate for 10 years. The remainder of CMI with BI underwent FMD with C1/2 fusion (n = 48). Among these, CXA values increased with 10 year progression-free survival rates of 74% and 93% with and without ventral compression, respectively.

CONCLUSION

For adult CMI without BI, C1/2 facet configurations and CXA are irrelevant. FMD alone provides excellent long-term outcomes. In CMI with BI, anterior C1 facet displacements indicate C1/2 instability. Posterior fusions can be reserved for patients with ventral compression or C1/2 instability.

Diagnosis and treatment of Chiari malformation and syringomyelia in adults: international consensus document

BACKGROUND

Syringomyelia and Chiari malformation are classified as rare diseases on Orphanet, but international guidelines on diagnostic criteria and case definition are missing.

AIM OF THE STUDY

to reach a consensus among international experts on controversial issues in diagnosis and treatment of Chiari 1 malformation and syringomyelia in adults.

METHODS

A multidisciplinary panel of the Chiari and Syringomyelia Consortium (4 neurosurgeons, 2 neurologists, 1 neuroradiologist, 1 pediatric neurologist) appointed an international Jury of experts to elaborate a consensus document. After an evidence-based review and further discussions, 63 draft statements grouped in 4 domains (definition and classification/planning/surgery/isolated syringomyelia) were formulated. A Jury of 32 experts in the field of diagnosis and treatment of Chiari and syringomyelia and patient representatives were invited to take part in a three-round Delphi process. The Jury received a structured questionnaire containing the 63 statements, each to be voted on a 4-point Likert-type scale and commented. Statements with agreement <75% were revised and entered round 2. Round 3 was face-to-face, during the Chiari Consensus Conference (Milan, November 2019).

RESULTS

Thirty-one out of 32 Jury members (6 neurologists, 4 neuroradiologists, 19 neurosurgeons, and 2 patient association representatives) participated in the consensus. After round 2, a consensus was reached on 57/63 statements (90.5%). The six difficult statements were revised and voted in round 3, and the whole set of statements was further discussed and approved.

CONCLUSIONS

The consensus document consists of 63 statements which benefited from expert discussion and fine-tuning, serving clinicians and researchers following adults with Chiari and syringomyelia.

Transoral digital reduction of complete anterior odontoid dislocation followed by fiducial-based navigated transcondylar screw fixation: illustrative case

BACKGROUND

Posterior atlantoaxial dislocations (i.e., complete anterior odontoid dislocation) without C1 arch fractures are a rare hyperextension injury most often found in high-velocity trauma patients. Treatment options include either closed or open reduction and optional spinal fusion to address atlantoaxial instability due to ligamentous injury.

OBSERVATIONS

A 60-year-old male was struck while on his bicycle by a truck and sustained an odontoid dislocation without C1 arch fracture. Imaging findings additionally delineated a high suspicion for craniocervical instability. The patient had neurological issues due to both a head injury and ischemia secondary to an injured vertebral artery. He was stabilized and transferred to our facility for definitive neurosurgical care.

LESSONS

The patient underwent a successful transoral digital closed reduction and posterior occipital spinal fusion via a fiducial-based transcondylar, C1 lateral mass, C2 pedicle, and C3 lateral mass construct. This unique reduction technique has not been recorded in the literature before and avoided potential complications of overdistraction and the need for odontoidectomy. Furthermore, the use of bone fiducials for navigated screw fixation at the craniocervical junction is a novel technique and recommended particularly for placement of technically demanding transcondylar screws and C2 pedicle screws where pars anatomy is potentially unfavorable.

Increase in clivo-axial angle is associated with clinical improvement in children undergoing occipitocervical fusion for complex Chiari malformation: patient series

BACKGROUND

The authors analyzed the pre- and postoperative morphometric properties of pediatric patients with complex Chiari malformation undergoing occipitocervical fusion (OCF) to assess clinical outcomes and morphometric properties that might influence postoperative outcomes.

OBSERVATIONS

The authors retrospectively reviewed 35 patients younger than 22 years with Chiari malformation who underwent posterior fossa decompression and OCF with or without endoscopic endonasal odontoidectomy at their institution (13 with and 22 without odontoidectomy). Clivo-axial angle (CXA), pB-C2, atlantodental interval, basion-dens interval, basion-axial interval, and canal diameter at the level of C1 were measured on preoperative and approximately 3-month postoperative computed tomography or magnetic resonance imaging. The authors further stratified the patient cohort into three age groups and compared the three cohorts. The most common presenting symptoms were headache, neck/shoulder pain, and dysphagia; 80% of the cohort had improved clinical outcomes. CXA increased significantly after surgery. When stratified into those who showed postoperative improvement and those who did not, only the former showed a significant increase in CXA. After age stratification, the significant changes in CXA were observed in the 7- to 13-year-old and 14- to 21-year-old cohorts.

LESSONS

CXA may be the most important morphometric predictor of clinical outcomes after OCF in pediatric patients with complex Chiari malformation.

Assessment of patients with a Chiari malformation type I

Introduction

The prevalence of Chiari malformation type I (CM-I) has been estimated as up to 1% of the general population. The majority of patients are asymptomatic and usually do not need treatment. Symptomatic patients, and some asymptomatic patients with associated conditions, may benefit from further assessment and treatment.

Research question

The aim of this review was to describe the clinical and radiological assessment of patients presenting with a CM-I.

Material and methods

A literature search was performed using the PubMed and Embase databases focused on clinical assessment and imaging techniques used to diagnose CM-I.

Results

Following a complete clinical evaluation in patients with symptomatic CM-I and/or radiologically significant CM-I (tonsillar impaction, resulting tonsillar asymmetry and loss of CSF spaces), MRI of the brain and whole spine enables an assessment of the CM-I and potential associated or causative conditions. These include hydrocephalus, syringomyelia, spinal dysraphism, and tethered cord. Flow and Cine MRI can provide information on CSF dynamics at the craniocervical junction, and help in surgical decision-making. Hypermobility or instability at the upper cervical and craniocervical junction is less common and can be measured with CT imaging and flexion/extension or upright MRI.

Discussion and conclusion

The majority of CM-I detected are incidental findings on MRI imaging of brain or spine, and do not require intervention. Once a radiological diagnosis and concern has been raised, clinical assessment by an appropriate specialist is required. A MRI brain and cervical spine is indicated in all radiologically labelled CM-I. In symptomatic patients or cases of radiologically significant CM-I, MRI of the brain and entire spine is indicated. Further investigations should be tailored to individuals' needs.

Predicting clinical outcomes using morphometric changes in adults with complex Chiari malformation undergoing occipitocervical fusion with or without ventral decompression: patient series

BACKGROUND

The authors assessed the connection between clinical outcomes and morphometrics in patients with complex Chiari malformation (CM) who have undergone posterior fossa decompression (PFD) and subsequent occipitocervical fusion (OCF) with or without ventral decompression (VD).

OBSERVATIONS

The authors retrospectively reviewed 33 patients with CM aged over 21 years who underwent PFD and OCF with or without endoscopic endonasal odontoidectomy at the authors’ institution (21 OCF only and 12 OCF + VD). Clivoaxial angle (CXA), pB-C2 (perpendicular line to the line between the basion and C2), atlantodental interval (ADI), basion-dens interval (BDI), basion-axial interval (BAI), and C1 canal diameter were measured on preoperative and approximately 3-month postoperative computed tomography or magnetic resonance imaging scans. Common symptoms included headache, paresthesia, and bulbar symptoms. Clinical improvement after surgery was observed in 78.8% of patients. CXA, ADI, and BDI all significantly increased after surgery, whereas pB-C2 and BAI significantly decreased. OCF + VD had a significantly more acute CXA and longer pB-C2 preoperatively than OCF only. Patients who clinically improved postoperatively showed the same significant morphometric changes, but those who did not improve showed no significant morphometric changes.

LESSONS

Patients showing improvement had greater corrections in skull base morphometrics than those who did not. Although there are various mutually nonexclusive reasons why certain patients do not improve after surgery, smaller degrees of morphometric correction could play a role.

Cervicogenic Dizziness Associated With Craniocervical Instability: A Case Report

Cervicogenic dizziness (CGD) is a clinical syndrome characterized by an illusory sensation of motion and disequilibrium secondary to neck pathologies. Reported here is the case of a 40-year-old male presented with neck pain, dizziness, and aural symptoms in the past 12 months. The patient was previously diagnosed with Meniere’s disease and treated with a low-sodium diet, betahistine and vestibular rehabilitation for 4 months, but the symptoms had not been relieved. Subsequently he sought out chiropractic evaluation. Radiographic clues illustrated a subtle anterolisthesis of the occiput on the cervical spine, manifested by a dissociation of the clivo-axial angle (CXA). After exclusion of other neurological, vascular and vestibular causes, craniocervical instability was considered as the cause of the CGD. He was treated with multi-component intervention consisting of spinal manipulation, intermittent motorized traction and ultrasound therapy to release cervical complaints. The patient reported salutary consequences to the 3-month treatment course with no neurologic sequelae. The current study serves as a vivid example of identifying CGD based on a subtle radiographic clue and by utilizing CXA as an assessment tool for craniocervical instability.

Ventral Tonsillar Herniation Predicts Headaches in Adults With Chiari Malformation

BACKGROUND

Radiographic characterization of Chiari malformation (CM) has historically focused on caudal tonsillar herniation (CH) below the foramen magnum. Previously, we published evidence linking ventral tonsillar herniation (VH) and medullary symptoms in very young children. We sought to extend that investigation by studying the radiographic and clinical significance of VH in adults diagnosed with CM.

METHODS

We retrospectively reviewed adults with cerebellar ectopia who underwent posterior fossa decompression with or without duraplasty (PFD/D) at our institution. VH was defined as tonsils crossing a line bisecting the caudal medulla at the level of the foramen magnum on axial MRI. Degree of VH was measured as distance between this bisecting line and the ventral tip of the herniated tonsil. Dorsal brainstem compression was qualitatively determined by assessing for obliteration of CSF space between the dorsal brainstem and the tonsils.

RESULTS

Out of 89 cases reviewed, 54 had some degree of VH. Compared with those without VH, the VH group was significantly older in age and more likely to also present with dorsal brainstem compression and headaches. No correlation was observed between degrees of CH and VH in the VH group. The degree of VH significantly decreased 3 months after PFD/D.

CONCLUSIONS

VH is relatively common in CM patients and might be an important independent radiographic metric to evaluate and consider as part of the decision-making process, especially in those presenting with Chiari-like symptomatology referable to the medulla but who do not meet the traditional criteria of cerebellar ectopia greater than 5 mm.

Opioid-free anesthesia for patients with joint hypermobility syndrome undergoing craneo-cervical fixation: a case-series study focused on anti-hyperalgesic approach

Background

Patients with Ehlers-Danlos Syndrome/Hypermobility Type (EDS-HT/JHS) and Craneo-Cervical Instability frequently suffer from severe widespread pain which is difficult to control. Chronic neuroinflammation, opioid-induced hyperalgesia, and central sensitization may explain this painful condition. The aim of this study was to determine if opioid-free anesthesia plus the postoperative administration of lidocaine, ketamine and dexmedetomidine can reduce postoperative pain and the need of methadone rescues in comparison with opioid-based management in these patients undergoing Craneo-Cervical Fixation (CCF). The secondary aim was to assess the needs of opioids at hospital-discharge, incidence of gastrointestinal complications and the requirement of anxiolytic.

Methods

A retrospective, consecutive case series study was designed. 42 patients with EDS-HT/JHS undergoing CCF were enrolled in two groups: an OFA-plus Group that received opioid-free anesthesia with propofol, lidocaine, ketamine and dexmedetomidine, and OP Group, opioid-based anesthesia-analgesia. The main variables: Preoperative Visual Analogue Score (VAS), postoperative VAS on the 1st, 2nd, 4th and 6th days, sufentanil or morphine requirements, need for methadone rescue, and VAS at hospital-discharge. Data was presented by mean ± SD, percentage, median or interquartile range. Chi-squared or Fisher’s test. 95% C.I and P values < 0.05.

Results

Nineteen patients in OFA-plus, and 23 patients in OP group. VAS was lower in OFA-plus on the postoperative days evaluated (p < 0.001).VAS at hospital-discharge was lower in OFA-plus: 4.96 (4.54–5.37) vs. OP 6.39 (6.07–6.71) (p < 0.001). Methadone requirement was lower in the OFA-plus (p < 0.001). 78% of patients in OFA-plus didn’t need methadone rescue. 95% in OP group needed methadone rescues at high doses(> 15 mg/day). No differences regarding equivalent doses of sufentanil or morphine consumption on the 2nd, 4th, and 6th postoperative days were found. OFA-plus decreased ileus, nausea and vomiting (p < 0.001). 60.9% in OFA-plus group decreased opioid requirements at hospital-discharge compared with preoperative values. A 77% reduction of anxiolytics requirements was shown.

Conclusion

OFA-plus management for patients undergoing CCF with EDS-HT/JHS shows significant reduction in postoperative pain and at hospital-discharge compared with opioid-based anesthesia. OFA-plus management decreases the total doses of methadone rescues, reduces anxiolytic requirements and gastrointestinal side-effects, except for constipation. OFA-plus management is a feasible option to improve postoperative pain control, reducing the opioids’ use and their postoperative side-effects in patients undergoing CCF with EDS-HT/JHS.

Ehlers-Danlos syndrome-associated craniocervical instability with cervicomedullary syndrome: Comparing outcome of craniocervical fusion with occipital bone versus occipital condyle fixation

Introduction:

Ehlers–Danlos syndrome (EDS) predisposes to craniocervical instability (CCI) with resulting cranial settling and cervicomedullary syndrome due to ligamentous laxity. This study investigates possible differences in radiographic outcomes and operative complication rate between two surgical techniques in patients with EDS and CCI undergoing craniocervical fusion (CCF): occipital bone (OB) versus occipital condyle (OC) fixation.

Methods:

A retrospective search of the institutional operative database between January 07, 2017, and December 31, 2019, was conducted to identify EDS patients who underwent CCF with either OB (Group OB) or OC (Group OC) fixation. For each patient, pre- and post-operative radiographic measurements and operative complications were extracted and compared between groups (OB vs. OC): pB-C2, clivoaxial angle (CXA), tonsillar descent, C2C7 sagittal Cobb angle, C2 long axis, and operative complications.

Results:

Of a total of 26 patients, 13 underwent OV and 13 underwent OC fixation. Eighty-five percent of the patients underwent OC underwent fusion from occiput to C2, while the remaining 15% fusion from occiput to C3. Radiographic outcome in the OC versus OB group was preoperative measurements were similar between OC and OB group: pB-C2 8.8 mm (1.5, 6–11) versus 8.3 mm (1.7, 4–9.6), P = 0.43; CXA 128.2° (5.4, 122–136) versus 131.9° (6.8,122–141), P = 0.41; tonsillar descent 6.2 mm (4.8, 0–15) versus 2.9 mm (3.4, 0–8), P = 0.05; C2 long axis 75.2° (6.7, 58–85) versus 67.2° (21.4, 1–80), P = 0.21; postoperative change of CXA + 14.4° (8.8, 0–30) versus 16.2° (12.4, −4–38), P = 0.43; change of pB-C2 − 2.6 mm (1.8, −-5.3 to 0) versus − 1.2 mm (4, −4.6–8), P = 0.26; and postoperative C2C7 sagittal Cobb angle − 2.6° (19.5, −43–39) versus − 2.6° (11.4, −21–12). Operative complications were seen in 1 out of 13 patients (8%) versus 2 out of 13 patients (16%), P = 1.

Conclusions:

In EDS, patients with CCI undergoing CCF radiographic and clinical outcome were similar between those with OC versus OB fixation. Both techniques resulted in sufficient correction of pB-C2 and CXA measurements with a low complication rate.

The Neurosurgical Intraoperative Checklist for Surgery of the Craniocervical Junction and Spine

Many sectors within healthcare have adapted checklists to improve quality control. Notwithstanding the reported successful implementation of surgical checklists in the operating theater, a dearth of literature addresses the specific challenges posed by complex surgery in the craniocervical junction and spine. The authors devised an intraoperative checklist to address the common errors and verify the completion of objectives unique to these surgeries. The data over six years is presented retrospectively; no historical control for comparison is available, as those omissions and surgical errors addressed by the checklist are not generally registered in any morbidity and mortality reports. Through six years and approximately 1200 surgeries, the checklist was implemented with 98% compliance. The checklist eliminated the occurrences of mundane surgical errors, minimized iatrogenic complications, and ensured completion of specific objectives. We discuss that preoperative checklists, now in general use in all hospitals, have not addressed the most common, intraoperative omissions. These technical omissions result in part from the complexity of spine surgery and directly impact the surgical outcome. The Neurosurgical Intraoperative Checklist is a practical, rapid, and comprehensive means to prevent common, avoidable errors and iatrogenic complications inherent to spine surgery.

Myofascial Flap Closure in Treatment for Patients With Craniocervical Instability and Ehlers-Danlos Syndrome

INTRODUCTION

The benefits of decompression and fusion for patients with craniocervical instability are well described. However, complications such as wound breakdown and need for unplanned reoperation frequently occur. Recent studies have shown advantages of myofascial flap closure for various spinal procedures. This study investigated whether closure with myofascial flaps after surgery for craniocervical instability decreases complications with further subgroup analysis of patients with Ehlers-Danlos syndrome (EDS).

METHODS

A retrospective review of patients presenting to Weill Cornell Medical Center from 2010 to 2017 for craniocervical surgery was performed. All patients who underwent craniocervical surgery, regardless of plastic surgical involvement, were included in the study. Data including patient demographics, comorbidities, EDS diagnosis, surgical history, complications, and follow-up information were collected and analyzed.

RESULTS

Data from 57 patients were analyzed. Eighteen patients (31.6%) had craniocervical surgery without myofascial flap closure, whereas 39 (68.4%) had surgery with flap closure. In the nonflap group, 9 patients required unplanned reoperation (50%). In the flap group, there were 5 patients requiring unplanned reoperation (15%). For reoperation, the Fisher exact test 2-tailed P value is 0.0096. Of those 57 patients, 24 had EDS: 5 (20.8%) had no flap closure, whereas 19 (79.2%) had flap closure. In the no-flap group, 3 patients required unplanned reoperation (60%). In the flap group, 5 patients required unplanned reoperation (21%). For reoperation, the Fisher exact test 2-tailed P value is 0.1265.

CONCLUSIONS

Patients undergoing surgery for craniocervical instability may benefit from myofascial flap closure even if they have EDS. Mobilizing well-vascularized tissue can decrease rates of reoperation.

Optimizing Alignment Parameters During Craniocervical Stabilization and Fusion: A Technical Note

Proper craniocervical alignment during craniocervical reduction, stabilization, and fusion optimizes cerebrospinal fluid (CSF) flow through the foramen magnum, establishes the appropriate “gaze angle”, avoids dysphagia and dyspnea, and, most importantly, normalizes the clival-axial angle (CXA) to reduce ventral brainstem compression. To illustrate the metrics of reduction that include CXA, posterior occipital cervical angle, orbital-axial or “gaze angle”, and mandible-axial angle, we present a video illustration of a patient presenting with signs and symptoms of the cervical medullary syndrome along with concordant radiographic findings of craniocervical instability as identified on dynamic imaging and through assessment of the CXA, Harris, and Grabb-Oakes measurements.

Impact of imaging modality, age, and gender on craniocervical junction angles in adults without structural pathology

Context:

Multiple angles of the craniocervical junction (CCJ) are associated with pathological conditions and surgical outcomes, including the clivo-axial angle (CXA), clival slope (CS), and sagittal axis (XS). However, there are varying normative ranges reported and a paucity of data analyzing the effects of imaging modality, age, and gender on these angles.

Setting and Design:

A retrospective review of computed tomographic (CT) and magnetic resonance imaging (MRI) scans in fifty adults without CCJ pathology from 2014 to 2019.

Methods:

Age, gender, indication, and hours between scans were recorded. Two-blinded observers measured all angles. Analysis between angles from the same patient was performed using the Wilcoxon signed-rank test. Multivariable linear regression was used to test for associations between average angles and age or gender.

Results:

Average age and time between scans were 41.3 and 14.3 h, respectively, with 94% performed due to trauma. On CT, average CXA, CS, and XS were 162.1°, 118.4°, and 81.3°, respectively. On MRI, they were 159.8°, 117.2°, 85.3°, respectively. There were statistically significant differences between CXA and XS (P < 0.01) based on imaging modality. On CT, there was a significant increase in XS by 1.93°° and decrease in CS by 1.88°° and on MRI, there was a significant increase in CXA by 1.93°° and decrease in CS by 2.75°° corresponding with a 10-year advancement of age. Gender did not have an effect.

Conclusion:

There are significant differences in angular measurements of the CCJ between CT and MRI from the same patient, as well as changes in normative values based on age.