Natural history of craniovertebral abnormalities in a single-center study in 54 patients with Hurler syndrome.

OBJECTIVE: Craniovertebral junction (CVJ) abnormalities are common and well documented in mucopolysaccharidosis type I-Hurler syndrome (MPS IH), often causing severe spinal canal narrowing. However, the requirement for surgical decompression and/or fusion is uncommon. Although hematopoietic cell transplant (HCT) has been shown to prolong the lives of patients with MPS IH, its effect in halting or reversing musculoskeletal abnormalities is less clear. Unfortunately, there are currently no universal guidelines for imaging or indication for surgical interventions in these patients. The goal of this study was to track the progression of the CVJ anatomy in patients with MPS IH following HCT, and to examine radiographic features in patients who needed surgical intervention. METHODS: Patients with MPS IH treated at the University of Minnesota with allogeneic HCT between 2008 and 2020 were retrospectively reviewed. Patients who underwent CVJ surgery were identified with chart review. All MPS IH cervical scans were examined, and the odontoid retroflexion angle, clivoaxial angle (CXA), canal width, and Grabb-Oakes distance (pB-C2) were measured yearly for up to 7 years after HCT. Longitudinal models based on the measurements were made. An intraclass correlation coefficient was used to measure interrater reliability. Nine children without MPS IH were examined for control CVJ measurements. RESULTS: A total of 253 cervical spine MRI scans were reviewed in 54 patients with MPS IH. Only 4 (7.4%) patients in the study cohort required surgery. Three of them had posterior fossa and C1 decompression, and 1 had a C1-2 fusion. There was no statistically significant difference in the spinal parameters that were examined between surgery and nonsurgery groups. Among the measurements, canal width and CXA varied drastically in patients with different neck positions. Odontoid retroflexion angle and CXA tended to decrease with age. Canal width and pB-C2 tended to increase with age. CONCLUSIONS: Based on the data, the authors observed an increase in canal width and pB-C2, whereas the CXA and odontoid retroflexion angle became more acute as the patients aged after HCT. The longitudinal models derived from these data mirrored the development in children without MPS IH. Spinal measurements obtained on MR images alone are not sufficient in identifying patients who require surgical intervention. Symptom monitoring and clinical examination, as well as pathological spinal cord changes on MRI, are more crucial in assessing the need for surgery than is obtaining serial imaging.

Anatomical variations of the atlas arches: prevalence assessment, systematic review and proposition for an updated classification system.

Objective and background: This study focuses on the atlas, a pivotal component of the craniovertebral junction, bridging the cranium and spinal column. Notably, variations in its arches are documented globally, necessitating a thorough assessment and categorization due to their significant implications in clinical, diagnostic, functional, and therapeutic contexts. The primary objective is to ascertain the frequency of these anatomical deviations in the atlas arches among a Colombian cohort using cone-beam computed tomography (CBCT). Methodology: Employing a descriptive, cross-sectional approach, this research scrutinizes the structural intricacies of the atlas arches in CBCT scans. Analytical parameters included sex distribution and the nature of anatomical deviations as per Currarino's classification. Statistical analyses were conducted to identify significant differences, including descriptive statistics and Chi-square tests. A systematic review of the literature was conducted in order to enhance the current Currarino's classification. Results: The study examined 839 CBCT images, with a nearly equal sex distribution (49.7% female, 50.3% male). Anatomical variations were identified in 26 instances (3%), displaying a higher incidence in females (X2 [(1, N = 839) = 4.0933, p = 0.0430]). The most prevalent variation was Type A (2.5%), followed by Type B (0.4%), and Type G (0.2%) without documenting any other variation. The systematic review yielded 7 studies. A novel classification system for these variations is proposed, considering global prevalence data in the cervical region. Conclusion: The study highlights a statistically significant predominance of Type A variations in the female subset. Given the critical nature of the craniovertebral junction and supporting evidence, it recommends an amendment to Currarino's classification to better reflect these clinical observations. A thorough study of anatomical variations of the upper cervical spine is relevant as they can impact important functional aspects such as mobility as well as stability. Considering the intricate anatomy of this area and the pivotal function of the atlas, accurately categorizing the variations of its arches is crucial for clinical practice. This classification aids in diagnosis, surgical planning, preventing iatrogenic incidents, and designing rehabilitation strategies.

[Analysis of clinical efficacy and risk factors of relapse in young patients with cervical instability treated by manipulation].

OBJECTIVE: To determine the clinical efficacy of different manipulation in the treatment of cervical instability in young people, and to analyze the risk factors of relapse of cervical instability in young people. METHODS: From March 2021 to June 2022, the clinical data of 120 young patients with cervical instability were retrospectively analyzed. According to the different treatment methods, they were divided into rotation group (60 cases, 3 cases of loss) and tendon group (60 cases, 5 cases of loss). There were 25 males and 32 females in rotation-traction manipulation group;age ranged from 22 to 44 years old with a median of 28 years old;course of disease ranged from 0.17 to 120 months with amedian of 22 months. There were 22 males and 33 females in tendon-regulating manipulation group;age ranged from 21 to 42 years old with a median of 27 years old;course of disease ranged from 0.23 to 180 months with a median of 24 months. Both groups were treated for 2 weeks, once every other day for 7 times, and were followed up for 1 year. The clinical efficacy of the two groups was evaluated, and the visual analogue scale (VAS), neck disability index (NDI) were observed before and after treatment. One year after the course of treatment, patients with effective treatment were followed up to make statistics on recurrence. Patients with recurrence were included in the recurrence group, while those without recurrence were included in the non-recurrence group. Factors that may affect symptom recurrence were analyzed, and univariate and multivariate Logistic regression analysis were performed. RESULTS: The 13 patients who failed the treatment (4 cases in the rotation-traction manipulation group and 9 cases in the tendon-regulating manipulation group) were not followed up. All the 99 patients who were effective in treatment were followed up ranged from 303 to 406 days with a median of 359 days. No complications occurred in all patients. There were significant differences in VAS and NDI between the two groups after treatment and before treatment (P<0.05), and there were significant differences in VAS and NDI between the two groups after treatment (P<0.05). Ninety-nine patients achieved follow-up, 56 (56.57%) relapsed and 43 (43.43%) did not. Univariate correlation analysis showed that NDI index, the time spent at the desk every day, the time spent using electronic products every day and angular displacement of anterior flexion before treatment in the relapse group were significantly higher than those in the non-relapse group (P<0.05). Logistic regression analysis showed that the time spent at the desk every day [OR=2.447, 95%CI(1.255, 4.771)], the time spent using electronic products every day [OR=1.892, 95%CI(1.066, 3.358)] and the angular displacement of anterior flexion of the cervical before treatment [OR=1.246, 95%CI(1.045, 1.485) ]were the risk factors for relapse. CONCLUSION: Both rotation-traction manipulation and tendon-regulating manipulation can effectively treat cervical instability in young people, and rotation-traction manipulation has more advantages than tendon-regulating manipulation in improving cervical pain and cervical dysfunction in patients. The time spent at the desk every day, the time spent using electronic products every day, and the increase of cervical flexion angle displacement will increase the risk of relapse in patients.

Atlantoaxial instability associated with ALDH18A1 mutation.

We report a 10-year-old boy with a de novo pathogenic variant in ALDH18A1, a rare form of metabolic cutis laxa, which was complicated by atlantoaxial instability and spinal cord compression following a fall from standing height. The patient required emergent cervical spine fusion and decompression followed by a 2-month hospitalization and rehabilitation. In addition to the core clinical features of joint and skin laxity, hypotonia, and developmental delays, we expand the connective tissue phenotype by adding a new potential feature of cervical spine instability. Patients with pathogenic variants in ALDH18A1 may warrant cervical spine screening to minimize possible morbidity. Neurosurgeons, geneticists, primary care providers, and families should be aware of the increased risk of severe cervical injury from minor trauma.

Cervical Instability and Quadriparesis Requiring Stabilization in Pediatric Patient Caused by a Mutation in COL2A1.

A 3-year-old male with no past medical history presented with flaccid plegia of his upper extremities and significant weakness in his lower extremities after wrestling with his brother. Cervical spine magnetic resonance imaging was consistent with cord edema and intraparenchymal hemorrhage at C1-C2. A nonossified tissue mass at the expected location of the upper dens created narrowing of the canal at the C1-2 level and mass effect on the cord. Head computed tomography showed periventricular leukomalacia. Initial findings favored dysplasia of the odontoid with associated soft tissue mass/pannus caused by a possible underlying genetic or metabolic bone dyscrasia. The patient underwent suboccipital craniotomy/C1 laminectomy and occiput to C4 fusion, for decompression and stabilization. Genetic testing showed a COL2A1 collagen disorder, with the child harboring a de novo mutation for c.3455 G>T (p.G1152V). The patient was discharged to inpatient acute rehabilitation, with gradual improvement in strength in all 4 extremities.

Clinical Outcomes of Open-Door Laminoplasty Combined with Bilateral Lateral Mass Screw Fixation for Multi-Level Cervical Spinal Stenosis with Traumatic Cervical Instability and Spinal Cord Injury: A Retrospective Study.

OBJECTIVES: The prevalence of multi-level cervical spinal stenosis complicated with traumatic cervical instability and spinal cord injury (MCSS-TCISCI) is low, and the optimal surgical approach remains unclear. Open-door laminoplasty combined with bilateral lateral mass screw fixation (ODL-BLMSF) is a relatively new surgical technique; however, its clinical effectiveness in managing MCSS-TCISCI has not been well-established. This study aims to assess the clinical value of ODL-BLMSF against MCSS-TCISCI. METHODS: We retrospectively analyzed 20 cases of MCSS-TCISCI treated with ODL-BLMSF from July 2016 to June 2020. Radiographic alterations of all included patients were measured using plain radiographs, CT scans, and MRI scans. Cervical lordosis was evaluated using C2-C7 Cobb angle and cervical curvature index (CCI) on lateral radiographs, and Pavlov ratio at the C5 level. Neurological functional recovery was assessed using Japanese Orthopaedic Association (JOA) scores and Nurick grade, while neck and axial symptoms were assessed using the neck disability index (NDI) and the visual analog scale (VAS). The paired t-test was utilized for statistical analysis. RESULTS: All included patients were followed up for an average period of 26.5 months (range: 24-30 months) after ODL-BLMSF. The average Pavlov ratio at the C5 level significantly improved from 0.57 ± 0.1 preoperatively to 1.13 ± 0.1 and 1.12 ± 0.04 at 6 months postoperatively and at the last follow-up (t = 16.347, 16.536, p < 0.001). Importantly, this approach significantly increased the JOA score from 5.0 ± 2.6 before surgery to 11.65 ± 4.3 and 12.1 ± 4.3 at 6 months postoperatively and at the last follow-up (t = 9.6, -9.600, p < 0.001), with an average JOA recovery rate of 59.1%; and the average Nurick disability score decreased from 3.0 ± 1.3 (preoperative) to 1.65 ± 1.22 and 1.5 ± 1.2 (6 months postoperatively and at last follow-up) (t = 5.111, 1.831, p < 0.001). Meanwhile, the NDI score decreased from 30.3 ± 4.3 preoperatively to 13.2 ± 9.2 at 6 months (t = 12.305, p < 0.001), and to 12.45 ± 8.6 at the final follow-up (t = 13.968, p < 0.001), while the VAS score decreased from 4.0 ± 1.5 preoperatively to 1.5 ± 0.7 at 6 months (t = 9.575, p < 0.001), and to 1.15 ± 0.7 at the final follow-up (t = 10.356, p < 0.001). CONCLUSION: ODL-BLMSF can effectively dilate the stenotic spinal canal to decompress the spinal cord, maintain good cervical alignment and stability, and improve the recovery of neurological function and neck function. This technique is suitable for treating selected cases of MCSS-TCISCI.

Corrigendum: Genetically predicted C-reactive protein mediates the association between rheumatoid arthritis and atlantoaxial subluxation.

[This corrects the article DOI: 10.3389/fendo.2022.1054206.].

Non-Surgical Management of Upper Cervical Instability via Improved Cervical Lordosis: A Case Series of Adult Patients.

Injury to the head and neck resulting from whiplash trauma can result in upper cervical instability (UCIS), in which excessive movement at C1 on C2 is observed radiologically. In some cases of UCIS there is also a loss of normal cervical lordosis. We postulate that improvement or restoration of the normal mid to lower cervical lordosis in patients with UCIS can improve the biomechanical function of the upper cervical spine, and thus potentially improve symptoms and radiographic findings associated with UCIS. Nine patients with both radiographically confirmed UCIS and loss of cervical lordosis underwent a chiropractic treatment regimen directed primarily at the restoration of the normal cervical lordotic curve. In all nine cases, significant improvements in radiographic indicators of both cervical lordosis and UCIS were observed, along with symptomatic and functional improvement. Statistical analysis of the radiographic data revealed a significant correlation (R2 = 0.46, p = 0.04) between improved cervical lordosis and reduction in measurable instability, determined by C1 lateral mass overhang on C2 with lateral flexion. These observations suggest that enhancing cervical lordosis can contribute to improvement in signs and symptoms of upper cervical instability secondary to traumatic injury.

Post-Traumatic Atlanto-Axial Instability: A Combined Clinical and Radiological Approach for the Diagnosis of Pathological Rotational Movement in the Upper Cervical Spine.

Post-traumatic rotational instability at the atlanto-axial (C1-2) joint is difficult to assess, much less quantify, due to the orientation and motion plane of the joint. Prior investigations have demonstrated that a dynamic axial CT scan, during which the patient maximally rotates the head right and left, can be used to evaluate and quantify the amount of residual overlap between the inferior articulating facet of C1 and the superior facet of C2, as an index of ligamentous laxity at the joint. We have previously demonstrated that a novel orthopedic test of rotational instability, the atlas-axis rotational test (A-ART), may have utility in identifying patients with imaging evidence of upper cervical ligament injury. In the present investigation, we assessed the correlation between a positive A-ART and a CT scan assessment of the relative quantity of residual C1-2 overlap, as a percent of the superior articulating facet surface area of C2. A retrospective review was conducted of the records of consecutive patients presenting to a physical therapy and rehabilitation clinic, over a 5-year period (2015-20) for chronic head and neck pain after whiplash trauma. The primary inclusion criteria were that the patient had undergone both a clinical evaluation with A-ART and a dynamic axial CT to evaluate for C1-2 residual facet overlap at maximum rotation. The records for a total of 57 patients (44 female/13 male) were identified who fit the selection criteria, and among these, there were 43 with a positive A-ART (i.e., "cases") and 14 with a negative A-ART (i.e., "controls). The analysis demonstrated that a positive A-ART was highly predictive of decreased residual C1-2 facet overlap: the average overlap area among the cases was approximately one-third that of the control group (on the left, 10.7% versus 29.1%, and 13.6% versus 31.0% on the right). These results suggest that a positive A-ART is a reliable indicator of underlying rotational instability at C1-2 in patients with chronic head and neck symptoms following whiplash trauma.

Short-Term and Long-Term Complications Associated with Posterior Fossa Decompression for Chiari Malformation.

Surgery is the treatment of choice for symptomatic patients with Chiari anomalies Although the surgical treatment of Chiari anomalies in adults is a straightforward procedure, complications and less than satisfactory outcomes do occur. Understanding these complications is important for correcting the problem as well as preventing the recurrence of similar problems. In this article, the author review the short-term and long-term complications associated with posterior fossa decompression for Chiari malformation.

Evaluation and management of orthostatic headache in hypermobility disorders.

Headache is a frequent symptom among patients with hypermobility spectrum disorders. This mini review focuses specifically on a challenging aspect of headache evaluation in all patients, but especially those with hypermobility - the orthostatic headache. While the differential for an orthostatic headache is overall limited, patients with hypermobility disorders have risk factors for all of the most commonly encountered orthostatic headache disorders. The most common conditions to produce orthostatic headaches are discussed - spontaneous intracranial hypotension, cervicogenic headache, and postural orthostatic tachycardia syndrome. Less common etiologies of orthostatic headache pertinent to any patient are presented in table format.

A case of atlantoaxial instability following skull base osteomyelitis: Tips for diagnosis and management.

Skull base osteomyelitis is a rare but dangerous consequence of untreated malignant otitis externa. Pseudomonas aeruginosa is responsible for most cases with typical presentation. Here, we discuss a diabetic 54-year-old female presented with malignant otitis externa and bilateral facial paresis followed by cervical spondylitis and C1-C2 instability. Skull base osteomyelitis confirmed by clinical presentation, imaging, and laboratory data. Fortunately, she responded well to antibacterial and antifungal therapy. Due to limited data, there is no confirmed standard of treatment for cervical instability secondary to SBO. It seems antibiotic therapy is the mainstay of treatment. In case of poor response to antibiotic therapy, surgical intervention is inevitable. This article introduces the first case of SBO-related AAI successfully managed with conservative treatment.

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.

Genetically predicted C-reactive protein mediates the association between rheumatoid arthritis and atlantoaxial subluxation.

Objective: Investigating the causal relationship between rheumatoid arthritis (RA) and atlantoaxial subluxation (AAS) and identifying and quantifying the role of C-reactive protein (CRP) as a potential mediator. Methods: Using summary-level data from a genome-wide association study (GWAS), a two-sample Mendelian randomization (MR) analysis of genetically predicted rheumatoid arthritis (14,361 cases, and 43,923 controls) and AAS (141 cases, 227,388 controls) was performed. Furthermore, we used two-step MR to quantitate the proportion of the effect of c-reactive protein-mediated RA on AAS. Results: MR analysis identified higher genetically predicted rheumatoid arthritis (primary MR analysis odds ratio (OR) 0.61/SD increase, 95% confidence interval (CI) 1.36-1.90) increased risk of AAS. There was no strong evidence that genetically predicted AAS had an effect on rheumatoid arthritis risk (OR 1.001, 95% CI 0.97-1.03). The proportion of genetically predicted rheumatoid arthritis mediated by C-reactive protein was 3.7% (95%CI 0.1%-7.3%). Conclusion: In conclusion, our study identified a causal relationship between RA and AAS, with a small proportion of the effect mediated by CRP, but a majority of the effect of RA on AAS remains unclear. Further research is needed on additional risk factors as potential mediators. In clinical practice, lesions of the upper cervical spine in RA patients need to be given more attention.

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.

Use of halo fixation therapy for traumatic cranio-cervical instability in children: a systematic review.

PURPOSE: Traumatic cranio-cervical instability in childhood is rare and constitutes a challenge for the treating surgeon. The aim of therapy is to restore cervical stability without limiting the range of motion. The goal of this systematic review was to find out whether, over the last 10 years, halo fixation (HF) could still be considered a successful treatment option without major risks or complications. METHODS: We analyzed studies describing the use of HF in traumatic injuries of the cranio-cervical junction in children under the age of 17. Searches were performed in PubMed, MEDLINE and Embase databases for the years from 2010 to 2020. The general success rate, the success rate related to underlying pathologies, and complication rates were evaluated. RESULTS: The main indications for HF range from pre-surgical correction to postoperative fusion support. C2 is the most frequently injured vertebra in children. The overall success rate of HF was very high. Evaluation according to the underlying pathology showed that, except for atlanto-occipital dislocation, HF generates high fusion rates among different patient cohorts, mainly in C2 vertebra injuries and atlantoaxial rotatory subluxation. Only minor complications were reported, such as pin infections. CONCLUSION: The current data show that, when used according to the appropriate indication, HF is an effective conservative treatment option for cranio-cervical instability, associated with only minor complications.

The pediatric "Spine at Risk" program: 9-year review of a novel safety screening tool.

PURPOSE: We implemented an EMR-based "Spine at Risk" (SAR) alert program in 2011 to identify pediatric patients at risk for intraoperative spinal cord injury (SCI) and prompt an evaluation for peri-operative recommendations prior to anesthetic. SAR alerts were activated upon documentation of a qualifying ICD-9/10 diagnosis or manually entered by providers. We aimed to determine the frequency of recommended precautions for those auto-flagged by diagnosis versus by provider, the frequency of precautions, and whether the program prevented SCIs during non-spinal surgery. METHODS: We performed a retrospective chart review of patients from 2011 to 19 with an SAR alert. We recorded how the chart was flagged, recommended precautions, and reviewed data for SCIs at our institution during non-spinal operations. RESULTS: Of the 3453 patients with an SAR alert over the 9-year study period, 1963 were auto-flagged by diagnosis and 1490 by manual entry. Only 38.7% and 24.3% of the patients in these respective groups were assigned precaution recommendations, making the auto-flag 62.8% better than providers at identifying patients needing precautions. Cervical spine positioning precautions were needed most frequently (86.7% of diagnosis-flagged; 30.0% of provider-flagged), followed by intraoperative neuromonitoring (IONM) (25.2%; 6.1%), thoracolumbar positioning restrictions (16.1%; 7.9%), and fiberoptic intubation (13.9%; 5.7%). There were no SCIs in non-spinal procedures during the study. CONCLUSION: EMR-based alerts requiring evaluation by a Neurosurgeon or Orthopaedic surgeon prior to anesthesia can prevent SCIs during non-spinal procedures. The majority of identified patients are not found to be at risk, and will not require special precautions. LEVEL OF EVIDENCE: III.

Surgical treatment outcome on a national cohort of 176 patients with cervical manifestation of rheumatoid arthritis.

PURPOSE: Rheumatoid arthritis (RA) affecting the cervical spine results in instability and deformity that can be divided into the subtypes C1-C2 horizontal (atlantoaxial instability), C0-C2 vertical (basilar invagination), subaxial, and combined instabilities. The aim of this study was to compare the surgical treatments and outcomes of RA-related deformity and instability in a population-based setting. PATIENTS AND METHODS: All patients with RA in the national Swespine register from January 1, 2006, to March 20, 2019, were assessed. Baseline characteristics, surgical treatments, European Myelopathy Scale (EMS), Neck Disability Index, the Visual Analog Scale for neck and arm pain as well as pre- and postoperative imaging were analyzed. The follow-up time points were at 1-, 2-, and 5 years after surgery. RESULTS: A total of 176 patients were included. There were 62 (35%) patients with C1-C2 horizontal instability, 48 (27%) with C0-C2 vertical instability, 19 (11%) patients with subaxial instability, 43 (24%) patients with combined instability, and 4 patients without instability served as controls. The EMS improved in the C1-C2 horizontal instability group after fusion surgery (Δ =2.6 p) but remained within baseline confidence intervals in the other groups. All patients regardless of instability improved in pain. The subaxial instability had the highest risk of death within 5 years after surgery (11/19, 58%). The most dangerous complications due to implant failure were seen in patients instrumented with laminar hooks. CONCLUSION: The neurological outcome after fusion surgery is poor and the death rate is high in patients with cervical RA-related instability and deformity.

Prevalence of Cervical Spondylolisthesis in the Sagittal Plane Using Radiographic Imaging in a Pediatric Population: A Cross Sectional Analysis of Vertebral Subluxation.

INTRODUCTION: Cervical Spondylolisthesis (CS) in children is under-studied. This cross-sectional study reports the CS prevalence in children. MATERIALS & METHODS: Subjects were selected from a private practice. Inclusion criteria: 0-17 years of age; documented demographics and health complaints; neutral lateral cervical (NLC) radiographs; and CS. Exclusion criteria: pseudosubluxation. RESULTS: 342 NLC radiographs were analyzed. 73 (21.3%) had CS greater than 2.0 mm. 42 (57.5%) had no musculoskeletal complaints. 8 (2.3%) had the presence of a CS greater than 3.5 mm. 5 (62.5%) had no musculoskeletal complaints. DISCUSSION: Pediatric populations endure various traumas. Pediatric cervical spine biomechanics has an increased risk of upper cervical spine injury. Regular spinal radiographic exams may help identify serious spinal conditions in their pre-symptomatic state. CONCLUSION: CS in pediatric populations is under-studied. CS is present in children and adolescents with and without symptoms.