scholarly journals Concept of 'Central' or 'Axial' Atlantoaxial Instability

2021 ◽  
Vol 18 (4) ◽  
pp. 4-11
Author(s):  
Atul Goel
Keyword(s):  
Odontoid Process ◽  
Dynamic Imaging ◽  
Atlantoaxial Instability ◽  
Clinical Implications ◽  
Atlantoaxial Joint ◽  
Process Understanding ◽  
Abnormal Increase ◽  
Manual Manipulation ◽  
Atlantodental Interval ◽  
Lateral Profile

The atlantoaxial joint is the most mobile joint of the spine and is most liable to develop instability. Atlantoaxial instability can be identified on observation of facetal alignment on lateral profile imaging, telltale clinical and radiological evidence and by direct observation of instability by manual manipulation of bones during surgery. Central or axial atlantoaxial instability is when there is no abnormal increase in atlantodental interval on dynamic imaging and there is no dural or neural compression by the odontoid process. Understanding and appropriately treating central or axial atlantoaxial instability can have clinical implications.

scholarly journals Transoral intraarticular cage distraction and C-JAWS fixation for revision of basilar invagination with irreducible atlantoaxial dislocation

2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Xiaobao Zou ◽  
Binbin Wang ◽  
Haozhi Yang ◽  
Su Ge ◽  
Bieping Ouyang ◽  
...  
Keyword(s):  
Revision Surgery ◽  
Odontoid Process ◽  
Basilar Invagination ◽  
Atlantoaxial Dislocation ◽  
Atlantoaxial Instability ◽  
Cervical Cord ◽  
Atlantoaxial Joint ◽  
Japanese Orthopedic Association ◽  
Satisfactory Outcome ◽  
Irreducible Atlantoaxial Dislocation

Abstract Background The revision surgery of basilar invagination (BI) with irreducible atlantoaxial dislocation (IAAD) after a previous occipitocervical fusion (OCF) is challenging. Transoral revision surgery has more advantages than a combined anterior and posterior approach in addressing this pathology. The C-JAWS is a cervical compressive staple that has been used in the lower cervical spine with many advantages. Up to now, there is no report on the application of C-JAWS in the atlantoaxial joint. We therefore present this report to investigate the clinical outcomes of transoral intraarticular cage distraction and C-JAWS fixation for revision of BI with IAAD. Methods From June 2011 to June 2015, 9 patients with BI and IAAD were revised by this technique after previous posterior OCF in our department. Plain cervical radiographs, computed tomographic scans and magnetic resonance imaging were obtained pre- and postoperatively to assess the degree of atlantoaxial dislocation and compression of the cervical cord. The Japanese Orthopedic Association (JOA) score was used to evaluate the neurological function. Results The revision surgeries were successfully performed in all patients. The average follow-up duration was 18.9 ± 7.3 months (range 9–30 months). The postoperative atlas-dens interval (ADI), cervicomedullary angle (CMA), distance between the top of the odontoid process and the Chamberlain line (CL) and JOA score were significantly improved in all patients (P < 0.05). Bony fusion was achieved after 3–9 months in all cases. No patients developed recurrent atlantoaxial instability. Conclusions Transoral revision surgery by intraarticular cage distraction and C-JAWS fixation could provide a satisfactory outcome for BI with IAAD after a previous unsuccessful posterior operation.

scholarly journals Atlantoaxial Instability in Down Syndrome

PEDIATRICS ◽  
1984 ◽  
Vol 74 (1) ◽  
pp. 152-154
Author(s):  
Keyword(s):  
Down Syndrome ◽  
Head And Neck ◽  
Cervical Vertebrae ◽  
Clinical Manifestations ◽  
Odontoid Process ◽  
Cervical Vertebra ◽  
Cervical Region ◽  
Atlantoaxial Instability ◽  
Atlantoaxial Joint ◽  
Special Olympics

Some issues related to participation in certain sports by persons with Down syndrome require clarification. Since 1965 there have been occasional reports about a condition described at various times as instability, subluxation, or dislocation of the articulation of the first and second cervical vertebrae (atlantoaxial joint) among persons with Down syndrome.1-15 This condition has also been found in patients with rheumatoid arthritis,16,17 abnormalities of the odontoid process of the second cervical vertebra,4,5,12,13,15 and various forms of dwarfism.18 Atlantoaxial (C-1, C-2) instability has not attracted general attention because clinical manifestations are rare and the condition is limited to a small portion of the population. The incidence of atlantoaxial instability among persons with Down syndrome has been reported by various observers to be 10% to 20%.2,9,15 When atlantoaxial instability results in subluxation or dislocation of C-1 and C-2, the spinal cord also may be injured. This is a rare but serious complication. In March 1983, the Special Olympics, Inc, sponsors of a nationwide competitive athletic program for developmentally disabled persons, without prior announcement, mandated for participants with Down syndrome special precautions to prevent serious neurologic consequences from stress on the head and neck in sports competition.19 Although thousands of persons with Down syndrome have taken part in sports events during the 15-year history of the Special Olympics without a known occurrence of neurologic complications due to participation, the new directive requires all persons with Down syndrome who wish to participate in certain sports that might involve stress on the head and neck (gymnastics, diving, pentathlon, butterfly stroke in swimming, diving start in swimming, high jump, soccer, and warm-up exercises that place undue stress on the head and neck muscles) to have a medical examination, lateral-view roentgenograms of the upper cervical region in full flexion and extension, and certification by a physician that the examination did not reveal atlantoaxial instability or neurologic disorder.

Atlantoaxial Instability in Down Syndrome: Subject Review

PEDIATRICS ◽  
1995 ◽  
Vol 96 (1) ◽  
pp. 151-154
Author(s):  
Keyword(s):  
Down Syndrome ◽  
Cervical Spine ◽  
Sports Medicine ◽  
Cervical Vertebrae ◽  
Odontoid Process ◽  
Disabled Persons ◽  
Atlantoaxial Instability ◽  
Atlantoaxial Joint ◽  
Special Olympics ◽  
Increased Risk

DEFINITION OF THE PROBLEM In 1984, the American Academy of Pediatrics (AAP) published a position statement on screening for atlantoaxial instability (AAI) in youth with Down syndrome.1 In that statement, the AAP supported the requirement introduced by the Special Olympics in 1983 that lateral neck radiographs be obtained for individuals with Down syndrome before they participate in the Special Olympics' nationwide competitive program for developmentally disabled persons. Those participants with radiologic evidence of instability are banned from certain activities that may be associated with increased risk of injury to the cervical spine. This policy seemed to be prudent in light of the information available at that time. However, the AAP Committee on Sports Medicine and Fitness recently has reviewed the data on which this recommendation was based and has decided that uncertainty exists concerning the value of cervical spine radiographs in screening for possible catastrophic neck injury in athletes with Down syndrome. The 1984 statement therefore has been retired. This review discusses the available research data on this subject. BACKGROUND AAI, also called atlantoaxial subluxation, denotes increased mobility at the articulation of the first and second cervical vertebrae (atlantoaxial joint). This condition is found not only in patients who have Down syndrome but also in some patients who have rheumatoid arthritis, abnormalities of the odontoid process of the axis, and various forms of dwarfism.1 The causes of AAI are not well understood but may include abnormalities of the ligaments that maintain the integrity of the C-1 and C-2 articulation, bony abnormalities of C-1 or C-2, or both.1-11

Odontoid cervical gout causing atlantoaxial instability: case report

2019 ◽  
Vol 30 (4) ◽  
pp. 541-544
Author(s):  
Justin Slavin ◽  
Marcello DiStasio ◽  
Paul F. Dellaripa ◽  
Michael Groff
Keyword(s):  
Rheumatoid Arthritis ◽  
Spinal Cord ◽  
Case Report ◽  
Physical Examination ◽  
Odontoid Process ◽  
Signs And Symptoms ◽  
Cord Compression ◽  
Atlantoaxial Instability ◽  
Posterior Stabilization ◽  
Rotatory Subluxation

The authors present a case report of a patient discovered to have a rotatory subluxation of the C1–2 joint and a large retroodontoid pannus with an enhancing lesion in the odontoid process eventually proving to be caused by gout. This patient represented a diagnostic conundrum as she had known prior diagnoses of not only gout but also sarcoidosis and possible rheumatoid arthritis, and was in the demographic range where concern for an oncological process cannot fully be ruled out. Because she presented with signs and symptoms of atlantoaxial instability, she required posterior stabilization to reduce the rotatory subluxation and to stabilize the C1–2 instability. However, despite the presence of a large retroodontoid pannus, she had no evidence of spinal cord compression on physical examination or imaging and did not require an anterior procedure to decompress the pannus. To confirm the diagnosis but avoid additional procedures and morbidity, the authors proceeded with the fusion as well as a posterior biopsy to the retroodontoid pannus and confirmed a diagnosis of gout.

scholarly journals Unstable odontoid fractures: technical appraisal of anterior extrapharyangeal open reduction internal fixation for irreducible unstable odontoid fractures. Patient series

2021 ◽  
Vol 2 (20) ◽  
Author(s):  
Sushil Patkar
Keyword(s):  
Open Reduction ◽  
Facet Joint ◽  
Open Reduction Internal Fixation ◽  
Atlantoaxial Instability ◽  
Rigid Fixation ◽  
Atlantoaxial Joint ◽  
Fracture Fragment ◽  
Odontoid Fractures ◽  
Atlantoaxial Fixation ◽  
Displaced Fracture

BACKGROUND Displaced odontoid fractures that are irreducible with traction and have cervicomedullary compression by the displaced distal fracture fragment or deformity caused by facetal malalignment require early realignment and stabilization. Realignment with ultimate solid fracture fusion and atlantoaxial joint fusion, in some situations, are the aims of surgery. Fifteen such patients were treated with direct anterior extrapharyngeal open reduction and realignment of displaced fracture fragments with realignment of the atlantoaxial facets, followed by a variable screw placement (VSP) plate in compression mode across the fracture or anterior atlantoaxial fixation (transarticular screws or atlantoaxial plate screw construct) or both. OBSERVATIONS Anatomical realignment with rigid fixation was achieved in all patients. Fracture fusion without implant failure was observed in 100% of the patients at 6 months, with 1 unrelated mortality. Minimum follow-up has been 6 months in 14 patients and a maximum of 3 years in 4 patients, with 1 unrelated mortality. LESSONS Most irreducible unstable odontoid fractures can be anatomically realigned by anterior extrapharyngeal approach by facet joint manipulation. Plate (VSP) and screws permit rigid fixation in compression mode with 100% fusion. Any associated atlantoaxial instability can be treated from the same exposure.

Atlantoaxial Instability

2018 ◽  
pp. 41-48
Author(s):  
Jonathan M. Parish ◽  
Domagoj Coric
Keyword(s):  
Cervical Spine ◽  
Ct Scan ◽  
Plain Film ◽  
Cord Compression ◽  
Atlantoaxial Instability ◽  
Cervical Cord ◽  
Screw Length ◽  
Cord Injury ◽  
Bony Anatomy ◽  
Atlantodental Interval

There are a number of different imaging modalities that can be used to confirm atlantoaxial instability. Plain film radiographs of the cervical spine can be used to assess the atlantodental interval (ADI). Cervical CT is necessary to assess the atlantoaxial bony anatomy as well as to assess the foramen transversarium at C1 and C2. In particular, CT scan should be used to estimate screw length, medial/lateral and cranial/caudal screw trajectory. MRI can also evaluate the extent of cervical cord compression or cord injury that has occurred due to atlantoaxial instability.

scholarly journals Relationship between the atlantodental interval and T1 slope after atlantoaxial fusion in patients with rheumatoid arthritis

BMC Surgery ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Byeong Jin Ha ◽  
Yu Deok Won ◽  
Je Il Ryu ◽  
Myung-Hoon Han ◽  
Jin Hwan Cheong ◽  
...  
Keyword(s):  
Rheumatoid Arthritis ◽  
Sagittal Alignment ◽  
Multivariate Logistic Regression Analysis ◽  
Atlantoaxial Instability ◽  
Atlantoaxial Fusion ◽  
T1 Slope ◽  
Significant Difference ◽  
Cervical Sagittal Alignment ◽  
Before And After ◽  
Atlantodental Interval

Abstract Background Atlantoaxial fusion has been widely used for the treatment of atlantoaxial instability (AAI). However, atlantoaxial fusion sacrifices the motion of atlantoaxial articulation, and postoperative loss of cervical lordosis and aggravation of cervical kyphosis are observed. We investigated various factors under the hypothesis that the atlantodental interval (ADI) and T1 slope may be associated with sagittal alignment after atlantoaxial fusion in patients with rheumatoid arthritis (RA). Methods We retrospectively investigated 64 patients with RA who underwent atlantoaxial fusion due to AAI. Radiological factors, including the ADI, T1 slope, Oc-C2 angle, cervical sagittal vertical axis, and C2–C7 angle, were measured before and after surgery. Results The various factors associated with atlantoaxial fusion before and after surgery were compared according to the upper and lower preoperative ADIs. There was a significant difference in the T1 slope 1 year after surgery (p = 0.044) among the patients with lower preoperative ADI values. The multivariate logistic regression analysis showed that the preoperative ADI (> 7.92 mm) defined in the receiver-operating characteristic curve analysis was an independent predictive factor for the increase in the T1 slope 1 year after atlantoaxial fusion (odds ratio, 4.59; 95% confidence interval, 1.34–15.73; p = 0.015). Conclusion We found an association between the preoperative ADI and difference in the T1 slope after atlantoaxial fusion in the patients with RA. A preoperative ADI (> 7.92 mm) was an independent predictor for the increase in the T1 slope after atlantoaxial fusion. Therefore, performing surgical treatment when the ADI is low would lead to better cervical sagittal alignment.

Biomechanical properties of the atlantoaxial joint with naturally-occurring instability in a toy breed dog

2015 ◽  
Vol 28 (05) ◽  
pp. 355-358 ◽  
Author(s):  
C. Precht ◽  
B. Riedinger ◽  
A. Bürki ◽  
F. Forterre
Keyword(s):  
Biomechanical Properties ◽  
Cord Compression ◽  
Protective Role ◽  
Atlantoaxial Instability ◽  
Tectorial Membrane ◽  
Atlantoaxial Joint ◽  
Lateral Bending ◽  
Atlanto Axial Joint ◽  
Gross Examination ◽  
Yorkshire Terrier

SummaryThe biomechanical properties of the atlanto-axial joint in a young Yorkshire Terrier dog with spontaneous atlantoaxial instability were compared to those of another young toy breed dog with a healthy atlantoaxial joint. The range-of-motion was increased in flexion and lateral bending in the unstable joint. In addition, lateral bending led to torsion and dorsal dislocation of the axis within the atlas. On gross examination, the dens ligaments were absent and a longitudinal tear of the tectorial membrane was observed. These findings suggest that both ventral and lateral flexion may lead to severe spinal cord compression, and that the tectorial membrane may play a protective role in some cases of atlantoaxial instability.

scholarly journals Occipital Condyle Fracture: A Case Report of a Typically Stable Fracture That Required Surgical Treatment

2018 ◽  
Vol 2018 ◽  
pp. 1-3 ◽  
Author(s):  
Takeshi Suzuki ◽  
Satoshi Maki ◽  
Masaaki Aramomi ◽  
Tomonori Yamauchi ◽  
Manato Horii ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Surgical Treatment ◽  
Facet Joint ◽  
Atlantoaxial Instability ◽  
Occipital Condyle ◽  
Asian Woman ◽  
Atlantoaxial Joint ◽  
Occipitocervical Fusion ◽  
Occipital Condyle Fracture ◽  
Condyle Fracture

An occipital condyle fracture (OCF) is a relatively rare trauma that is now increasingly diagnosed because of the wide availability of computed tomography. For nondisplaced OCFs, conservative treatment is generally recommended, and there is no previous report of a nondisplaced OCF requiring surgery. We report a patient who had a nondisplaced OCF with craniocervical misalignment (a condyle-C1 interval > 2.0 mm) and C1-C2 translation treated with a halo vest and occipitocervical fusion surgery. An 87-year-old Asian woman fell from a 4-meter height and hit her head. She was transferred to our emergency room. Computed tomography revealed a nondisplaced impaction OCF with a 2.5 mm occipital condyle-C1 interval and a 5 mm C1-C2 translation. The fracture pattern was considered stable. However, since craniocervical misalignment and C1-C2 translation were present, the patient was placed in a halo device, and we reduced the occipitoatlantoaxial joint, adjusting the halo ring position preoperatively. Confirming reduction of the atlantooccipital facet joint and the atlantoaxial joint by computed tomography, we performed an occipitocervical fusion. This is the first report of a nondisplaced OCF with craniocervical misalignment and C1-C2 translation that required surgical treatment. Clinicians should be aware of craniocervical misalignment and atlantoaxial instability even in Tuli type 1 OCFs.

Treatment of basilar invagination by atlantoaxial joint distraction and direct lateral mass fixation

2004 ◽  
Vol 1 (3) ◽  
pp. 281-286 ◽  
Author(s):  
Atul Goel
Keyword(s):  
Odontoid Process ◽  
Craniovertebral Junction ◽  
Basilar Invagination ◽  
Foramen Magnum ◽  
Atlantoaxial Joint ◽  
Lateral Mass ◽  
Content Type ◽  
Joint Distraction ◽  
History Of ◽  
Fine Print

Object. The author discusses the successful preliminary experience of treating selected cases of basilar invagination by performing atlantoaxial joint distraction, reduction of the basilar invagination, and direct lateral mass atlantoaxial plate/screw fixation. Methods. Twenty-two patients with basilar invagination—in which the odontoid process invaginated into the foramen magnum and the tip of the odontoid process was above the Chamberlain, McRae foramen magnum, and Wackenheim clival lines—were selected to undergo surgery. In all patients fixed atlantoaxial dislocations were documented. The 16 male and six female patients ranged in age from 8 to 50 years. A history of trauma prior to the onset of symptoms was documented in 17 patients. Following surgery, the author observed minimal-to-significant reduction of basilar invagination and alteration in other craniospinal parameters resulting in restoration of alignment of the tip of the odontoid process and the clivus and the entire craniovertebral junction in all patients. In addition to neurological and radiological improvement, preoperative symptoms of torticollis resolved significantly in all patients. The minimum follow-up period was 12 months and the mean was 28 months. Conclusions. Joint distraction and firm lateral mass fixation in selected cases of basilar invagination is a reasonable surgical treatment for reducing the basilar invagination, restoring craniospinal alignment, and establishing fixation of the atlantoaxial joint.

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