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Radiographics : a Review Publication of... 2013
Topics: Adult; Axis, Cervical Vertebra; Forecasting; Humans; Magnetic Resonance Imaging; Male; Practice Guidelines as Topic; Sacroiliitis; Spondylarthropathies
PubMed: 24006535
DOI: 10.1148/Radiographics.33.4.135015 -
Radiographics : a Review Publication of... 2013
Topics: Adult; Axis, Cervical Vertebra; Forecasting; Humans; Magnetic Resonance Imaging; Male; Practice Guidelines as Topic; Sacroiliitis; Spondylarthropathies
PubMed: 24006534
DOI: 10.1148/Radiographics.33.4.125100 -
Neurology India 2022
Topics: Humans; Neck Pain; Odontoid Process; Syndrome
PubMed: 35864713
DOI: 10.4103/0028-3886.349617 -
Cell Jan 1999
Review
Topics: Animals; Axis, Cervical Vertebra; Body Patterning; Embryonic and Fetal Development; Functional Laterality; Humans
PubMed: 9988215
DOI: 10.1016/s0092-8674(00)80560-7 -
British Medical Journal Jul 1976
Topics: Arthritis, Rheumatoid; Axis, Cervical Vertebra; Brain Diseases; Cervical Atlas; Humans; Joint Dislocations
PubMed: 974490
DOI: No ID Found -
Neurology India 2015
Topics: Humans; Odontoid Process; Spinal Fractures
PubMed: 25751462
DOI: 10.4103/0028-3886.152657 -
Neurospine Jun 2019To describe the biomechanically relevant anatomy of the Axis vertebra and the load transfer patterns within the bone, and on that basis, to postulate its mechanism of...
To describe the biomechanically relevant anatomy of the Axis vertebra and the load transfer patterns within the bone, and on that basis, to postulate its mechanism of injury, a literature review was conducted of the anatomy and biomechanics of Axis fractures. Two hypotheses have been presented: the internal gear hypothesis and the leaf spring hypothesis. Both are based on the trabecular anatomy of the vertebra and its load transmission patterns. The relationship of the Axis with Hangman's injury is also discussed. According to the leaf spring hypothesis, the C2 pedicle corresponds to the shackle in the assembly and constitutes the weak link. The trabecular architecture of the Axis is such that the primary compression of the trabeculae is directed from the superior facet to the C2-3 endplate, with few trabeculae directed to the inferior facet. Along with the trabecular void in this area, this renders the isthmus vulnerable to trauma. The isthmus of the Axis is biomechanically susceptible to injury due to its unique anatomy in relation to the whole cervical spine and the internal load transmission patterns of the bone. The author suggests that in the flexion type of Hangman's injury, the C1-2 posterior ligaments are disrupted and need to be addressed.
PubMed: 31261461
DOI: 10.14245/ns.1938140.070 -
American Journal of Veterinary Research Dec 2017OBJECTIVE To evaluate and compare morphological characteristics of the dens in atlantoaxial instability (AAI)-predisposed toy-breed dogs (TBDs) with and without AAI and...
OBJECTIVE To evaluate and compare morphological characteristics of the dens in atlantoaxial instability (AAI)-predisposed toy-breed dogs (TBDs) with and without AAI and non-AAI-predisposed healthy Beagles. ANIMALS 80 AAI-affected and 40 nonaffected TBDs and 40 Beagles. PROCEDURES Each dog underwent CT examination of the cervical vertebral column. On median 3-D multiplanar reconstruction images, the dens angle (DA) was measured as were the lengths of the dens and the body of the axis; the dens-to-axis length ratio (ratio of the dens length to the axis body length [DALR]) was calculated. Data were compared among dog groups. RESULTS The DALR in nonaffected TBDs and Beagles did not differ significantly. The mean DALR for AAI-affected TBDs was significantly lower than that for nonaffected TBDs. The mean DA of AAI-affected TBDs was significantly greater than that of Beagles and nonaffected TBDs. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated that a low DALR might be associated with a high probability of dens abnormalities in TBDs. Additionally, dens length in AAI-affected TBDs appeared to be smaller than that in non-AAI-affected TBDs, given the low DALR in AAI-affected TBDs. Further investigations to determine reference ranges of the DA and DALR and the potential usefulness of those variables as diagnostic markers for AAI in TBDs are warranted.
Topics: Animals; Atlanto-Axial Joint; Cervical Atlas; Cervical Vertebrae; Dog Diseases; Dogs; Female; Joint Instability; Male; Odontoid Process; Reference Values; Retrospective Studies; Species Specificity; Tomography, X-Ray Computed
PubMed: 29182395
DOI: 10.2460/ajvr.78.12.1400 -
Orthopaedic Surgery May 2022First, to propose a novel minimally invasive technique of full-endoscopic anterior odontoid fixation (FEAOF) that aims to reduce the risk of retropharyngeal approach...
OBJECTIVE
First, to propose a novel minimally invasive technique of full-endoscopic anterior odontoid fixation (FEAOF) that aims to reduce the risk of retropharyngeal approach (both open and percutaneous techniques) to anterior odontoid screw fixation. Second, to describe steps of the procedure and, lastly, to report the initial outcomes in patients treated with this novel technique.
METHODS
Four non-consecutive patients who were diagnosed with a displaced odontoid fracture (Anderson-D'Alonzo classification type II and Grauer subclassification type A or B) from 2019 to 2020 underwent surgical fixation by our novel technique for anterior odontoid screw fixation. A detailed technical approach of FEAOF for the surgical treatment of type II odontoid fractures was described, and the patients' outcomes based on postoperative radiographic results including computed tomography (CT), clinical outcome parameters including visual analogue scale (VAS) for neck pain both preoperatively and at postoperative follow-up, and range of neck motion at the final follow-up were reported.
RESULTS
The mean age was 33.5 years (24-41), three patients were male. The mean operative time was 93.75 min, and the mean blood loss was 7.5 ml. An immediate post-operative thin-sliced CT showed that all patients achieved satisfactory reduction and proper screw position. No screw malposition or penetration was found. At a 6-month follow-up, a thin-sliced CT demonstrated solid bony union in every case. The mean VAS for neck pain was reduced from 6.5 to 0.6 at the 6-months follow-up. At the final follow-up, all patients showed improvement in ranges of motion without any complications; however, one patient was lost to follow-up.
CONCLUSIONS
FEAOF is a feasible and effective option for treating type II odontoid fractures. The procedure is less invasive than other techniques and provides clear direct visualization of the involved structures.
Topics: Adult; Bone Screws; Female; Follow-Up Studies; Fracture Fixation, Internal; Fractures, Bone; Humans; Male; Neck Pain; Odontoid Process; Spinal Fractures; Treatment Outcome
PubMed: 35445547
DOI: 10.1111/os.13271 -
Arquivos de Neuro-psiquiatria Nov 2012Evaluate the surgical results of axis screw instrumentation.
OBJECTIVE
Evaluate the surgical results of axis screw instrumentation.
METHODS
Retrospective evaluation of the clinical and radiological data of patients submitted to axis fixation using screws.
RESULTS
Seventeen patients were surgically treated. The mean age was 41.8 years (range: 12-73). Spinal cord trauma was the most common cause of instability (8 patients - 47%). Bilateral axis fixation was performed in all cases, except one, with laminar screw (total of 33 axis screws). Seven patients (41.1%) underwent bilateral pars screws; laminar screws were used in six cases and pedicular screws were used in two. In two cases, we performed a hybrid construction (laminar + pars and pedicle + pars). There was no neurological worsening or death, nor complications directly related to use axis screws.
CONCLUSION
Axis instrumentation was effective and safe, regardless of the technique used for stabilization. Based on our learnt experience, we proposed an algorithm to choose the best technique for axis screw fixation.
Topics: Adolescent; Adult; Aged; Algorithms; Axis, Cervical Vertebra; Bone Screws; Child; Follow-Up Studies; Humans; Joint Instability; Male; Middle Aged; Retrospective Studies; Spinal Cord Injuries; Spinal Fusion; Young Adult
PubMed: 23175198
DOI: 10.1590/s0004-282x2012001100007