[A quantitative study of mechanics in the treatment of atlantoaxial joint disorder by tendon relaxation manipulation].

OBJECTIVE: To explore dose-effect relationship of biomechanical parameters in treating atlantoaxial joint disorder by slimming manipulation. METHODS: From October 2022 to May 2023, 18 patients with atlantoaxial joint disorders were treated, including 10 males and 8 females;aged from 24 to 27 years old with an average of (25.50±1.10) years old;CT of cervical vertebra showed 16 patients with right side distortion and 2 patients with left side distortion. The mechanical parameters of treatment of atlantoaxial joint disorder by tendon relaxation manipulation were measured by wearing massage manipulation gloves. The magnitude, frequency and mechanical curve of force during tendon relaxation and starting force, pulling force, pulling time and mechanical curve during rehabilitation were quantified, the differences between the affected and contralateral manipulations were compared. RESULTS: The maximum force and frequency of Fengchi(GB20) on the affected side were (19.82±2.02) N and (116.83±14.49) times/min, and opposite side were (13.87±2.19) N and (188.89±16.03) times/min, respectively. There were statistically difference in the maximum force and frequency of both sides (P<0.05). The maximum force and frequency of Quepen (ST12) on the affected side were (14.44±3.27) N and (139.06±28.47) times/min, and those on the opposite side were (9.41±1.38) N and (142.50±28.47) times/min. There was difference in maximum force on both sides (P<0.05). The starting force, turning force and turning time of the affected side were (14.16±5.98) N, (11.56±6.63) N, (0.14±0.03) S, and the contralateral side were (8.94±3.39) N, (8.30±4.64) N, (0.18±0.04) S, respectively. The difference of starting force, turning force and turning time on both sides were statistically significant (P<0.05). CONCLUSION: By applying a light relaxation force on the affected side, the mechanical balance between cervical vertebrae could be restored, and recovery trend of atlantoaxial joint disorder could be strengthened. On this basis, the atlantoaxial odontoid process could be reversed by applying a light rotation force, which reflects the characteristics of high safety of the manipulation.

Physiotherapeutic Approach Towards Sensory and Motor Recovery in a Patient With Lateral Mass Fixation: A Report of a Rare Case.

Atlantoaxial dislocations (AAD) are a diverse set of C1-C2 rotatory subluxations that include the inferior and superior axial facet articulations. C1-C2 segments are both covered by cranial-cervical ligaments, indicating that AAD would damage both joints. Whenever the posterior elements are missing or impaired, lateral mass screw fixation has replaced alternative posterior cervical fixation procedures as the preferred treatment for securing the sub-axial cervical spine. An increase in muscle tone, hyperreflexia, pathological reflexes, digit/hand clumsiness, and gait deviations caused by spinal cord compression at the cervical level are the most common clinical features. A 23-year-old female patient came with the chief complaint of weakness, tingling sensation, and numbness in both upper and lower limbs along with imbalance while walking. She had a history of falls which was managed conservatively. As the symptoms progressed, an MRI, a CT scan, and an X-ray of the neck were done to rule out the level of injury which revealed AAD, and the patient was operated on for C1-C2 lateral mass fixation. Post-operatively, the patient was referred to the physiotherapy department for further management. The patient's quality of life and daily functioning were positively affected after undergoing early intervention as measured by the Functional Independence Measure, Neck Disability Index, Berg Balance Scale, and Dynamic Gait Index.

Vertical Subluxation Caused by Infection Around the Odontoid Process: A Case Report.

Introduction: There are few reports of cases with vertical subluxation. We report our experience of a vertical subluxation of the atlantoaxial joint caused by infection. Case Report: A 63-year-old man had a 5-month history of neck pain. He was treated for rheumatoid arthritis by a local doctor. At admission to our hospital, he had neck pain and complained of dysphagia and hoarseness. His white blood cell count and C-reactive protein were 7200/mm3 and 4.86 mg/dL. Cervical X-ray showed atlantoaxial subluxation. Computed tomography showed osteolysis around the odontoid process, including the atlantooccipital and atlantoaxial joints, causing vertical subluxation. Magnetic resonance imaging showed spinal cord and brainstem compression and the presence of fluid. Gadolinium-enhanced magnetic resonance imaging showed enhancement around the odontoid process. We performed occipital-cervical spine fixation and C1 laminectomy. Following surgery, his symptoms completely resolved. Bone fusion was confirmed 6 months after surgery. Conclusion: If subluxation of the upper cervical spine occurs rapidly, infection should be considered.

Reliability and head-loading effects in imaging diagnosis of vertical subluxation in patients with rheumatoid arthritis.

OBJECTIVES: The purpose of this study was to examine the reproducibility of vertical subluxation (VS) parameters using X-ray, computed tomography (CT), and tomosynthesis (TS) while comparing the head-loading effects. METHODS: The VS parameters of 26 patients (retrospective review) were evaluated. Using the intra-class correlation coefficient, we statistically examined the intra-rater and inter-rater reliabilities of the parameters. Head-loaded and -unloaded imagings were compared using a Wilcoxon signed-rank test. RESULTS: The intra-rater reliability of TS and CT showed intra-class correlation coefficients of ≥0.8 (X-ray range: 0.6-0.8), with similar results for the inter-rater reliabilities. Furthermore, in head-loading imaging, the TS had significantly higher VS scores than that of CT (P < .05). CONCLUSIONS: In comparison with the X-ray, TS and CT were more accurate and reproducible. In terms of head loading, the VS values for TS were worse than those for CT, indicating that TS was more effective than CT in diagnosing VS.

C2 Superior Facetal Osteotomy: A Novel Technique in Complex Craniovertebral Junction Surgery for C1 Lateral Mass Screw Placement.

Complex craniovertebral junction (CVJ) defects account for a considerable proportion of CVJ diseases. Given the heavily assimilated C1, an unfavorable C1-C2 joint orientation, an overriding C2 superior facet, a low-hanging occiput, and an abnormal vertebral artery course with a high-riding vertebral artery, placement of C1 lateral mass screws might be difficult. To address this, a novel technique for placing C1 lateral mass screws that avoid vertebral artery injury, low-hanging occiput, and overriding C2 superior facet was developed in this study. This approach enables firm fixation of C1-C2 even in difficult situations where the placement of the C1 lateral mass is challenging.

Anterior Transarticular Crossing Screw Fixation for Atlantoaxial Joint Instability: A Biomechanical Study.

OBJECTIVE: To evaluate the biomechanical stability of anterior transarticular crossing screw (ATCS) and compare it with anterior transarticular screw (ATS) which may provide basic evidence for clinical application. METHODS: Eight human fresh cadaveric specimens (occiput-C4) were tested with 5 conditions including the intact status, the injury status (type II odontoid fracture), the injury+ATS fixation status (traditional bilateral ATS fixation); the injury+unilateral ATCS fixation status; and the injury+bilateral ATCS fixation status. Specimens were applied to a pure moment of 1.5 Nm in flexion-extension, lateral bending, and axial rotation, respectively. The range of motions (ROMs) and the neutral zones (NZs) of C1 to C2 segment were calculated and compared between 5 status. RESULTS: ATS and ATCS fixations significantly reduced the motions in all directions when compared with the intact and injury statues (p < 0.05). In flexion-extension, the ROMs of ATS, unilateral ATCS, and bilateral ATCS were 4.7° ± 2.5°, 4.1° ± 1.9°, and 3.2° ± 1.2°, respectively. Bilateral ATCS resulted in a significant decrease in ROM in flexion-extension when compared with ATS and unilateral ATCS (p = 0.035 and p = 0.023). In lateral bending and axial rotation, there was no significant difference in ROM between the 3 fixations (p > 0.05). Three fixations resulted in similar NZs in all directions (p > 0.05). CONCLUSION: ATCS is a biomechanically effective alternative or supplemental method for atlantoaxial instability.

Posterior pedicle screw fixation combined with local steroid injections for treating axial eosinophilic granulomas and atlantoaxial dislocation: A case report.

BACKGROUND: Eosinophilic granuloma (EG) is a proliferative condition that affects the cells of bone tissue. There are no specific clinical signs or imaging manifestations in the early stages of the disease, making it simple to overlook and misdiagnose. Because of the disease's rarity, there is presently no standardized treatment principle. There are few accounts of such occurrences affecting the axis among children. We discovered a case of a child whose EG resulted in atlantoaxial joint dislocation and destruction of the axial bone. CASE SUMMARY: After having pharyngeal discomfort for more than six months without a clear explanation, a 6-year-old boy was brought to our hospital. Following a careful evaluation, the pathology indicated a strong likelihood of an axial EG. Ultimately, we decided to treat the boy with posterior pedicle screw fixation and local steroid injections. CONCLUSION: EGs of the upper cervical spine are quite uncommon in children, and they are exceedingly easy to overlook or misdiagnose. Posterior pedicle screw fixation and local steroid injections are effective treatments for patients with axial EGs affecting the atlantoaxial junction.

Iatrogenic atlantoaxial rotatory subluxation after thyroidectomy in a pediatric patient: A case report.

BACKGROUND: Atlantoaxial rotatory subluxation (AARS) is an uncommon disease with a greater prevalence among children than adults, and it is mostly associated with trauma. Iatrogenic spinal injury accounts for a low percentage of injuries. However, in AARS, 20%-40% of cases are associated with surgery, and 48% are caused by infection. Here, we describe our experience with a case of iatrogenic AARS after general anesthesia. CASE SUMMARY: A 12-year-old girl presented with right-sided torticollis and cervical motion limit. The patient had undergone thyroidectomy 2 mo ago. Computed tomography revealed AARS with bilateral locked facets. Following the failure of repeated external reduction under general anesthesia, the patient underwent an open surgical reduction. The patient gained atlantoaxial alignment without any complications. Follow-up radiographs showed a normal appearance without instability. The cervical spine of children is more predisposed to injury due to anatomical and biomechanical differences. AARS secondary to infection and surgery is known as Grisel's syndrome, which involves non-traumatic AARS. Several cases of AARS after surgery and other procedures with no evidence of inflammation have been reported. Our experience shows that surgery requiring hyperextension of the neck after general anesthesia should also be included as a risk factor. CONCLUSION: Surgeons and anesthesiologists should be careful not to excessively extend the neck during pediatric surgery. Moreover, clinicians caring for pediatric patients with recent head and neck procedures must be aware of common AARS presentations.

Grisel's syndrome and Down syndrome: a case report.

Grisel's syndrome is a non-traumatic subluxation of the atlantoaxial joint following an inflammatory process in the upper respiratory tract. Patients with Down syndrome have higher risks of developing atlantoaxial instability. This issue is mainly due to low muscle tone, loose ligaments, and alterations to the bone in patients with Down syndrome. Accompaniment of Grisel's syndrome and Down syndrome was not perused in recent investigations. To our knowledge, only one case of Grisel's syndrome in an adult patient with Down syndrome has been reported. In this study, we present a case of Grisel syndrome in a 7-year-old boy with Down syndrome following lymphadenitis. A 7-year-old boy with Down syndrome was admitted to the orthopedic ward of Shariati hospital with a possible diagnosis of Grisel's syndrome and treated with mento-occipital traction for ten days. In this case report, we represent a child with Down syndrome with Grisel's syndrome for the first time. We also imitated a simple and applicable non-surgical treatment for Grisel's syndrome.

The association between unilateral high-riding vertebral artery and atlantoaxial joint morphology: a multi-slice spiral computed tomography study of 396 patients and a finite element analysis.

BACKGROUND CONTEXT: A high-riding vertebral artery (HRVA) can deviate too medially, too posteriorly, or too superiorly to allow the safe insertion of screws. However, it is unknown whether the presence of a HRVA is associated with morphological changes of the atlantoaxial joint. PURPOSE: To investigate the association between HRVA and atlantoaxial joint morphology in patients with and without HRVA. STUDY DESIGN: A retrospective case-control study and finite element (FE) analysis. PATIENT SAMPLE: A total of 396 patients with cervical spondylosis underwent multi-slice spiral computed tomography (MSCT) of cervical spine at our institutions from 2020 to 2022. OUTCOME MEASURES: A series of atlantoaxial joint morphological parameters, including C2 lateral mass settlement (C2 LMS), C1-2 sagittal joint inclination (C1-2 SI), C1-2 coronal joint inclination (C1-2 CI), atlanto-dental interval (ADI), lateral atlanto-dental interval (LADI), and C1-2 relative rotation angle (C1-2 RRA) were measured, and lateral atlantoaxial joints osteoarthritis (LAJs-OA) was recorded. The stress distribution on the C2 facet surface under different torques of flexion-extension, lateral bending, and axial rotation was analyzed by FE models. A 2-Nm moment was applied to all models to determine the range of motion (ROM). METHODS: A total of 132 consecutive cervical spondylosis patients with unilateral HRVA were enrolled in the HRVA group, and 264 patients without HRVA matched for age and sex were enrolled in the normal (NL) group. Atlantoaxial joint morphological parameters were compared between two sides of C2 lateral mass within HRVA or NL group, and between HRVA and NL groups. A 48-year-old woman with cervical spondylosis without HRVA was selected for cervical MSCT. A three-dimensional (3D) FE intact model of the normal upper cervical spine (C0-C2) was created. We established the HRVA model by simulating atlantoaxial morphological changes of unilateral HRVA with FE method. RESULTS: The C2 LMS was significantly smaller on the HRVA side than that on the non-HRVA side in the HRVA group, but C1-2 SI, C1-2 CI, and LADI on HRVA side were significantly larger than those on non-HRVA side. There was no significant difference between left and right sides in the NL group. The difference in C2 LMS (d-C2 LMS) between HRVA side and non-HRVA side in the HRVA group was larger than that in the NL group (P < 0.05). Meanwhile, the differences in C1-2 SI (d-C1/2 SI), C1-2 CI (d-C1/2 CI), and LADI (d-LADI) in the HRVA group were significantly larger than those in the NL group. The C1-2 RRA in the HRVA group was significantly larger than that in the NL group. Pearson correlations showed that d-C1/2 SI, d-C1/2 CI, and d-LADI were positively associated with d-C2 LMS (r=0.428, 0.649, 0.498, respectively, p<.05 for all). The incidence of LAJs-OA in the HRVA group (27.3%) was significantly larger than that in the NL group (11.7%). Compared with the normal model, the ROM of C1-2 segment declined in all postures of the HRVA FE model. We found a larger distribution of stress on the C2 lateral mass surface of the HRVA side under different moment conditions. CONCLUSIONS: We suggest that HRVA affects the integrity of the C2 lateral mass. This change in patients with unilateral HRVA is associated with the nonuniform settlement of the lateral mass and an increase in the lateral mass inclination, which may further affect the degeneration of the atlantoaxial joint because of the stress concentration on the C2 lateral mass surface.

Clinical features of atlantoaxial involvement in patients with rheumatoid arthritis using 18F-fluorodeoxyglucose-positron emission tomography with computed tomography.

INTRODUCTION/OBJECTIVES: Cervical spine involvement is one of the most serious complications in rheumatoid arthritis (RA). The study aim was to assess the clinical significance of atlantoaxial (AA) joint involvement detected by 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) with computed tomography (CT) in patients with RA. METHOD: A prospective cross-sectional study was conducted to evaluate AA joint involvement detected by FDG-PET/CT in consecutive RA patients from December 2017 to February 2022. We investigated the relationship between AA joint involvement and clinical data, including disease activity and patients' cervical symptoms. RESULTS: Among 48 patients enrolled, abnormal FDG uptake at AA joint was detected in 13 (27%). Rheumatoid factor titre, initial disease activity score 28-erythrocyte sedimentation rate and total standardized uptake value were significantly higher in the 13 patients than in the others (P = 0.004, P < 0.001 and P = 0.001, respectively). All patients with abnormal FDG uptake at AA joint had some cervical symptoms regardless of cervical spine X-ray abnormalities. Neck pain on movement and at rest were more frequent in the 13 patients than in the others (P = 0.001 and P = 0.004, respectively). The most sensitive symptom associated with AA joint involvement was neck pain on movement (sensitivity, 69%), and the most specific symptom was neck pain at rest (specificity, 100%). CONCLUSIONS: AA joint involvement was commonly observed by FDG-PET/CT in patients with active RA, independent of radiographic findings. Specific cervical symptoms can be important surrogate markers for detection of potential AA synovitis associated with active RA. Key Points • AA joint involvement was frequently seen in RA with high disease activity independent of radiographic findings. • Neck pain was a hallmark of AA joint involvement reflecting disease activity, and resting pain was highly specific.

Posterior Atlantoaxial Screw Placement in a Portuguese Population: A Morphometric Analysis Based on Computed Tomography Scan Measurements.

Objective The present study aims to evaluate the screw length and trajectory angles for posterior atlantoaxial fixation in a Portuguese population, through the study of cervical computed tomography (CT) scans. Methods Cervical CT scans of 50 adults were measured according to predefined screw trajectories of C1-C2 transarticular (C1C2TA), C1 lateral mass (C1LM), C2 pedicle (C2P), C2 pars and C2 laminar (C2L) screws. For each of these trajectories, screw length and angles were measured and compared between males and females. Results For the C1C2TA screw trajectory, the mean length, medial, and cranial angles were 34.12 ± 3.19 mm, 6.24° ± 3.06, and 59.25° ± 5.68, respectively, and for the C1LM screw trajectory, they were 27.12 ± 2.15 mm, 15.82° ± 5.07, and 13.53° ± 4.80, respectively. The mean length, medial, and cranial angles for the C2P screw trajectory were 23.44 ± 2.49 mm, 27.40° ± 4.88, and 30.41° ± 7.27, respectively; and for the C2 pars screw trajectory, they were 16.84 ± 2.08 mm, 20.09° ± 6.83, and 47.53° ± 6,97. The mean length, lateral, and cranial angles for the C2L screw trajectory were 29.10 ± 2.48 mm, 49.80° ± 4.71, and 21.56° ± 7.76, respectively. There were no gender differences except for the lengths of the C1C2TA ( p = 0,020) and C2L ( p = 0,001) screws, which were greater in males than in females. Conclusion The present study provides anatomical references for the posterior atlantoaxial fixation in a Portuguese population. These detailed data are essential to aid spine surgeons to achieve safe and effective screw placement.

Posterior Atlantoaxial Screw Placement in a Portuguese Population: A Morphometric Analysis Based on Computed Tomography Scan Measurements / Colocação de parafusos atlantoaxiais posteriores em uma população portuguesa: Uma análise morfométrica baseada em medidas de tomografia computadorizada

Abstract Objective The present study aims to evaluate the screw length and trajectory angles for posterior atlantoaxial fixation in a Portuguese population, through the study of cervical computed tomography (CT) scans. Methods Cervical CT scans of 50 adults were measured according to predefined screw trajectories of C1-C2 transarticular (C1C2TA), C1 lateral mass (C1LM), C2 pedicle (C2P), C2 pars and C2 laminar (C2L) screws. For each of these trajectories, screw length and angles were measured and compared between males and females. Results For the C1C2TA screw trajectory, the mean length, medial, and cranial angles were 34.12 ± 3.19 mm, 6.24° ± 3.06, and 59.25° ± 5.68, respectively, and for the C1LM screw trajectory, they were 27.12 ± 2.15 mm, 15.82° ± 5.07, and 13.53° ± 4.80, respectively. The mean length, medial, and cranial angles for the C2P screw trajectory were 23.44 ± 2.49 mm, 27.40° ± 4.88, and 30.41° ± 7.27, respectively; and for the C2 pars screw trajectory, they were 16.84 ± 2.08 mm, 20.09° ± 6.83, and 47.53° ± 6,97. The mean length, lateral, and cranial angles for the C2L screw trajectory were 29.10 ± 2.48 mm, 49.80° ± 4.71, and 21.56° ± 7.76, respectively. There were no gender differences except for the lengths of the C1C2TA (p= 0,020) and C2L (p= 0,001) screws, which were greater in males than in females. Conclusion The present study provides anatomical references for the posterior atlantoaxial fixation in a Portuguese population. These detailed data are essential to aid spine surgeons to achieve safe and effective screw placement.

Resumo Objetivo O presente estudo tem como objetivo avaliar o comprimento e os ângulos de trajetória do parafuso para fixação atlantoaxial posterior em uma população portuguesa por meio do estudo de tomografia computadorizada (TC) cervical. Métodos Tomografias computadorizadas cervicais de 50 adultos foram analisadas quanto às trajetórias pré-definidas dos parafusos transarticulares C1-C2 (C1C2TA), na massa lateral de C1 (C1LM), no pedículo de C2 (C2P) e na pars de C2 e C2 laminar (C2L). O comprimento e os ângulos dos parafusos em cada uma destas trajetórias foram medidos e comparados entre homens e mulheres. Resultados O comprimento médio e ângulos medial e cranial da trajetória do parafuso C1C2TA foram de 34,12 ± 3,19 mm, 6,24° ± 3,06 e 59,25° ± 5,68, respectivamente; as medidas da trajetória do parafuso C1LM foram 27,12 ± 2,15 mm, 15,82° ± 5,07 e 13,53° ± 4,80. O comprimento médio e os ângulos medial e cranial da trajetória do parafuso C2P foram de 23,44 ± 2,49 mm, 27,40° ± 4,88 e 30,41° ± 7,27, respectivamente; as medidas da trajetória do parafuso da pars de C2 foram 16,84 ± 2,08 mm, 20,09° ± 6,83 e 47,53° ± 6,97. O comprimento médio e ângulos lateral e cranial da trajetória do parafuso C2L foram de 29,10 ± 2,48 mm, 49,80° ± 4,71 e 21,56° ± 7,76, respectivamente. Não houve diferenças entre os gêneros, à exceção do comprimento dos parafusos C1C2TA (p= 0,020) e C2L (p= 0,001), que foi maior no sexo masculino do que no feminino. Conclusão O presente estudo fornece referências anatômicas para a fixação atlantoaxial posterior em uma população portuguesa. Estes dados detalhados são essenciais para ajudar os cirurgiões de coluna a colocar os parafusos de maneira segura e eficaz.

Posterior C1-C2 fusion for atlantoaxial rotatory fixation after posterior fossa craniotomy in a 4-year old: a case report.

INTRODUCTION: This study aimed to highlight that atlantoaxial rotatory fixation (AARF) can be related to neurosurgery procedures in children, with an afterward demonstration of good results after halo-gravity traction and C1-C2 stabilization using the Harms technique. CASE DESCRIPTION: To the best of our knowledge, this is the first case to report a 4-year-old boy who presented with AARF after a posterior fossa craniotomy to treat a cerebellar astrocytoma. At our medical facility, AARF was diagnosed using plain radiography and computed tomography imaging. The patient was treated with continuous cranial traction for 14 days. Initially, we detected that the patient had no C1 posterior arch or C2 spinous process; therefore, the best option was to perform the Harms technique. Postoperatively, the patient was placed in a cervical collar for 4 weeks. At the 4-year postoperative follow-up, the patient was doing well and had not developed any complications. CONCLUSION: Herein, we report a case in which AARF can be developed after neurosurgical procedure. Surgical techniques used for atlantoaxial subluxation should be carefully selected. In our case, the Harms technique after cranial traction was an excellent option for correcting and stabilizing the abnormal neck position. However, further studies are required to determine the best technique to use in the pediatric population.

Risk factors for atlantoaxial dislocation in rheumatoid arthritis: A comparative study.

BACKGROUND: The objective of the study was to assess clinical and imaging features of rheumatoid arthritis associated with atlantoaxial dislocation (RA-AAD) in comparison to RA without AAD (RA-C) and to identify the associated factors to AAD. METHODS: This was a retrospective comparative study including RA patients over 18 years old. The control group of RA-C was matched according to age (±2 years), gender, and RA duration (±2 years). General data, RA characteristics, AAD features, and treatment modalities were recorded. Statistical analysis was performed to determine the predictive factors of AAD. RESULTS: A total of 120 patients were included (78 RA-AAD and 42 RA-C); sex-ratio was 0.15. Mean age was 58.55 ± 9.14 years (RA-AAD) versus 60.43 ± 10.78 years (RA-C), (p = 0.31). Regarding RA features, RA-AAD patients have significantly a higher rheumatoid factor (RF) rate (p = 0.002), extra-articular manifestations (p = 0.009) especially osteoporosis (p < 10-3 ), eye involvement (p = 0.02), coxitis (p < 0.0001), Disease Activity Score (DAS28) (p < 10-3 ), and global health status scale (HAQ) (p = 0.003). X-ray analysis showed pathologic PADI (<14 mm) in 51.6% of cases. The AADI was pathological (>3 mm) in 100% of patients with the following distribution: 67.9% between (3-6 mm) and 23.3% between (6-9 mm). Atlantoaxial dislocation (AAD) was presumed anterior (85.4%), lateral (7.3%) and rotatory (7.3%). The abnormalities observed on magnetic resonance imaging (MRI) were: C1-C2 synovitis (61%), confirmed AAD (34.1%) and basilar impression (4.9%). AAD diagnosed by cervical MRI was anterior in 89.8% of cases, lateral (5.3%) and with a double ascending and anterior component in 4.9% of cases. An immobilisation with a type C4 cervical collar was indicated for all the patients and five of them had boluses of corticosteroid (methylprednisolone 1 g/day) for three consecutive days. C1-C2 arthrodesis by trans-articular screwing was performed in four patients with neurological signs or pathological measurements on cervical MRI. The outcome was favourable in 100% of cases after surgical treatment with improvement in neck pain and neurological condition within a mean decline of 4 ± 3 years [1-7]. Multivariate analysis identified coxitis, osteoporosis, high baseline DAS28, and a high rate of RF positivity as predictive factors of AAD. CONCLUSION: Our results confirmed that predictive factors of AAD were related to higher disease activity and structural damage. These modifiable factors may be prevented by tight control, early treatment, and educating RA patients to improve treatment adherence.

Characterization of Alar Ligament in Young Adult on 3.0T MRI: A Cross-sectional Study in IIUM Medical Centre, Kuantan

@#Introduction: Alar ligament is a paired craniocervical junction ligaments which stabilizes the atlantooccipital and atlantoaxial joints. The main purpose of the study was to compare the normal anatomy of alar ligament on MRI between male and female. The prevalence of alar ligament visualized on MRI and its characteristics were also studied apart from determining the association between the heights of respondents with alar ligament signal intensity and dimensions. Methods: Fifty healthy volunteers were studied using 3.0T MR scanner (Siemens Magnetom Spectra) by 2-mm proton density, T2 and fat-suppression sequences. Alar ligament visualization, dimensions and variability of the ligament courses, shapes and signal intensity characteristics were determined. Results: The orientation of the ligament was laterally ascending in most of the subjects (60%), predominantly oval in shaped (54%) and 67% showed inhomogenous signal. Females are 70% less likely to exhibit alar ligament signal inhomogeneity than males. There were positive correlation between height and the craniocaudal diameter of the alar ligament as well as the anteroposterior diameter, which were statistically significant (r = 0.25, n = 100, p = 0.01 and r = 0.201, n = 100, p = 0.045 respectively). Conclusion: Tremendous variability of alar ligament shows that clinical and multimodality correlation needs to be exercised, especially in evaluating alar ligament MR signal in male. Taller individuals otherwise tend to have longer and thicker ligaments. Future studies with larger samples of alar ligaments including trauma cases are also recommended to supplant a new classification system of alar ligament injury.

The Short-term Effectiveness of Three Manipulations for Atlantoaxial Joint Disorders and the Effects on Surface Electromyography of Sternocleidomastoid Muscle / 中医杂志

ObjectiveTo compare the short-term effectiveness of the three different manipulations for atlantoaxial joint disorders and their effects on surface electromyography of sternocleidomastoid muscle. MethodsNinty patients with atlantoaxial joint disorders were randomly divided into the tendon relaxing manipulation group， the tendon relaxing plus rehabilitation manipulation group， and the conventional manipulation group， with 30 cases in each group， and each group of patients received the corresponding manipulation treatment for 2 weeks. The changes of visual analogue score （VAS） of occipital neck pain， evaluation scale for cervical vertigo （ESCV）， and averaged electromyography （AEMG） of surface electromyography of bilateral sternocleidomastoid muscles before and after the treatment were observed， and the clinical effectiveness and safety of the patients were compared among groups. ResultsThe VAS scores of patients in each group decreased， and the ESCV scores increased after treatment （P＜0.01）， and the tendon relaxing manipulation group and the tendon relaxing plus rehabilitation manipulation group were significantly better than the conventional manipulation group （P＜0.01）. The AEMG of the bilateral sternocleidomastoid muscles of the three groups increased after treatment （P＜0.01）； when compared among the three groups， the AEMG of the bilateral sternocleidomastoid muscles of the tendon relaxing plus rehabilitation manipulation group was higher than that of the tendon relaxing manipulation group， and the tendon relaxing manipulation group was higher than that of the conventional manipulation group （P＜0.05 or P＜0.01）. The cure and markedly effective rates of the tendon relaxing manipulation group， the tendon relaxing plus rehabilitation manipulation group， and the conventional manipulation group were 56.67%， 86.67%， and 36.67% respectively， showing statistically difference （K=10.21， P＜0.01）. ConclusionThe tendon relaxing manipulation and tendon relaxing plus rehabilitation manipulation can effectively improve the symptoms of vertigo， headache， and neck pain for patients with atlantoaxial joint disorders， and can improve the contraction function of sternocleidomastoid muscle， whose effectiveness are better than that of conventional manipulation.

Factors Associated with Retro-Odontoid Pseudotumor in Long-Term Hemodialysis Patients.

OBJECTIVE: Hemodialysis has been reported to be associated with retro-odontoid pseudotumor (ROP), but its clinical characteristics have not been well described. The purpose of the present study was to investigate the factors associated with ROP in hemodialysis patients. METHODS: A retrospective clinical study of hemodialysis patients was conducted with the evaluation of computed tomography and magnetic resonance imaging of cervical spinal lesions at a single institution from 2012 to 2020. The patients' characteristics and radiographic findings were assessed. A case-control analysis was performed between patients with ROP (ROP group) and patients without ROP (control group). RESULTS: We analyzed 46 patients. The mean duration of hemodialysis (± standard deviation) was 21.5 ± 11.8 years. The mean retro-odontoid soft tissue thickness was 4.3 ± 0.3 mm and was correlated with the duration of hemodialysis (r = 0.46, P < 0.01). Thirty patients (65.2%) were included in the ROP group. The ROP group showed a significantly longer duration of hemodialysis (24.9 ± 11.2 years vs. 15.2 ± 10.3 years, P < 0.01) and a higher incidence of osteolytic lesions in the atlantoaxial joint compared with the control group (60.0% vs. 18.8%, P < 0.01). Logistic regression analysis revealed the atlantoaxial osteolytic lesions are associated with retro-odontoid pseudotumor in hemodialysis patients (odds ratio, 5.1; 95% confidence interval, 1.1-24.2; P = 0.04). CONCLUSIONS: The existence of ROP in hemodialysis patients was associated with osteolytic lesions in the atlantoaxial joint. The finding of atlantoaxial erosive lesions in long-term hemodialysis patients requires spine surgeons to carefully evaluate the presence of ROP.

Imaging Characterization of Non-Rheumatoid Retro-Odontoid Pseudotumors: Comparison with Atlantoaxial Manifestation of Rheumatoid Arthritis.

Backgroundand Objectives: To date, imaging characterization of non-rheumatic retro-odontoid pseudotumors (NRROPs) has been lacking; therefore, NRROPs have been confused with atlantoaxial joint involvement of rheumatoid arthritis (RA). It is important to differentiate these two disease because the treatment strategies may differ. The purpose of this study is to characterize imaging findings of NRROPs and compare them with those of RA. Material and Methods: From January 2015 to December 2019, 27 patients (14 women and 13 men) with NRROPs and 19 patients (15 women and 4 men) with RA were enrolled in this study. We evaluated various imaging findings, including atlantoaxial instability (AAI), and measured the maximum diameter of preodontoid and retro-odontoid spaces with magnetic resonance imaging (MRI) and computed tomography (CT). Results: Statistical significance was considered for p < 0.05. AAI was detected in eight patients with NRROPs and in all patients with RA (p < 0.0001). Seventeen patients with NRROPs and six patients with RA showed spinal cord compression (p = 0.047). Compressive myelopathy was observed in 14 patients with NRROPs and in 4 patients with RA (p = 0.048). Subaxial degeneration was observed in 25 patients with NRROPs and in 9 patients with RA (p = 0.001). Moreover, C2-3 disc abnormalities were observed in 11 patients with NRROPs and in 2 patients with RA (p = 0.02). Axial and longitudinal diameter of retro-odontoid soft tissue and preodontoid and retro-odontoid spaces showed significant differences between NRROP and RA patients (p < 0.0001). Furthermore, CT AAI measurements were differed significantly between NRROP and RA patients (p < 0.05). Conclusions: NRROPs showed prominent retro-odontoid soft tissue thickening, causing compressive myelopathy and a high frequency of subaxial and C2-3 degeneration without AAI.

The Effectiveness of Intraarticular Cervical Facet Steroid Injections in the Treatment of Cervicogenic Headache: Systematic Review and Meta-analysis.

BACKGROUND: Cervicogenic headache (CGH) can often be difficult to treat, given the overlapping clinical features of other headaches and the varying sources of pain that patients report. While imaging is not useful in diagnosing CGH, anesthetic blockade of the atlanto-occipital joint, lateral atlantoaxial joint, or specific cervical zygapophyseal joints can be used to confirm the diagnosis. When conservative treatment measures, such as physical therapy, fail, interventional techniques, such as intraarticular steroid injections, have been shown in observational studies to provide relief in some patients. OBJECTIVES: To determine the efficacy of intraarticular cervical facet steroid injections in the treatment of CGH. STUDY DESIGN: Systematic review and meta-analysis. METHODS: We conducted a comprehensive search of Ovid Medline, Embase, Cochrane Central Register of Controlled Trials , Cumulative Index to Nursing and Allied Health Literature Plus with Full Text, Scopus, and the Web of Science platform, from inception to April 2021, for studies using intraarticular cervical facet injections to treat CGH in adults aged 18 or older. Primary outcomes included mean postinjection pain scores. Outcomes were pooled using a random effects model and reported as mean differences (MD) with 95% confidence intervals (CI). RESULTS: Three studies with a total of 64 patients met the inclusion criteria. According to data from each of the included studies, intraarticular cervical facet injections were shown to demonstrate improvement in the mean pain score from baseline to postintervention. The overall effect size-pooled MD in the Visual Analog Scale score-was 3.299 (95% CI: 2.045 to 4.552, P < 0.001). Heterogeneity (I2) was 36.11%. LIMITATIONS: Small sample size, lack of control group, and varying pain generators and interventional technique between studies contribute to the limitations of the analysis. CONCLUSIONS: Our findings suggest that therapeutic intraarticular cervical facet injections may be effective in the treatment of CGH. Because of the heterogeneity among the studies, these results should be interpreted with caution.