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At least 217 records · Page 12Linked to original sources
PubMed1983

Congenital atlanto-axial dislocation.

Report about 105 personally operated cases of congenital atlanto-axial dislocation. This fairly common malformation in India occurs three times more in males than in females, 50% show symptoms before the age of 20 years, the other half during the third decade of life. Transient attacks of cervical cord compression occur with progressive motor and posterior column defect, and sometimes unconsciousness and cerebellar involvement are characteristic. The diagnosis is proved by X-rays including tomograms and dynamic studies. Three types of malformation can be differentiated: Group I with assimilation of the atlas, group II with anomalies of the odontoid process and group III with a normal atlas and axis. The different types and subtypes are described in detail as well as the pathological and pathogenic factors. The treatment and personal experiences show that the early treatment with posterior decompression, sometimes combined with posterior fusion was unsuccessful and resulted in a high mortality and morbidity. The antero-lateral approach, described by the author proved to be the method choice. The prognosis is dependent on the extent of the damage to the cord before treatment. Early diagnosis and treatment lead to excellent results.

Adolescent↗
PubMed2003

[Traumatic atlanto-axial rotatory fixation with lateral mass fracture of the axis].

Traumatic atlanto-axial rotatory fixation (AARF) is a relatively uncommon injury, especially in association with fractures of the axis. The rotatory dislocation and fixation is normally caused by intercalated facet joints of axis and atlas. A traumatic AARF in a 21 year old female is presented with special emphasis on the diagnostic and therapeutic approaches. This high velocity injury was caused by a traffic accident. The trauma service which was initially involved made the correct diagnosis and tried to reduce the dislocation by skull traction during analgesia and sedation, but without success. For further treatment, the patient was referred to a level one trauma center. After completing the diagnostic imaging with MRI and CT for exact delineation of the fracture site and determination of ligament damage, a halo fixation for skull traction was installed. This second attempt was also unsuccessful. Only a closed reduction under general anesthesia with muscle relaxation led to a neutral alignment and congruent joint contact between C1 and C2. Due to the stable fracture site and the intact ligaments, a conservative treatment with a stable collar splint was performed.

Accidents, Traffic↗
PubMed1995

Differential expression of the chicken Pax-1 and Pax-9 gene: in situ hybridization and immunohistochemical analysis.

We report the cloning, partial sequence analysis, and spatiotemporal expression of the chicken Pax-1 (chPax-1) and Pax-9 (chPax-9) gene, two closely related members of the paired box-containing (PAX) gene family. The chPax-1 gene encodes RNAs of 2.0 and 4.3 kb and a 42 kD protein while the gene products of chPax-9 are represented by 1.9 and 3.1 kb transcripts and a 39 kD protein. In situ hybridization and immunohistochemical analyses reveal chPax-1 expression in the developing pectoral girdle, in cells of the ventral part of sclerotomes, in sclerotome cells of the perichordal tube, and, later in development, in sclerotome-derived cells of the intervertebral disks. Other chPax-1 expression domains detected in the mesenchyme surrounding the atlas and axis and in chondrocytes of immature vertebral bodies, so far unreported for mouse Pax-1, correlate with as yet unexplained malformations in the mouse Pax-1 mutant undulated and Undulated-short tail. Overlapping expression of chPax-1 and chPax-9 is detected in epithelial cells of the embryonic and adult thymus and in cells of the developing intervertebral disks. Unlike chPax-1, however, chPax-9 is not expressed in those perichordal sclerotome cells which are thought to give rise to vertebral bodies. Furthermore, chPax-9 gene products are detected in circumscribed areas of mesenchyme in the metatarsus and in entodermal derivatives, i.e., in the lining epithelium of the developing pharynx and of the embryonic and adult esophagus.

Amino Acid Sequence↗
PubMed1977

Craniometaphysial dysplasia with leukoencephalopathy. A case report.

A case of craniometaphysial dysplasia with extensive degeneration of the cerebral white matter is presented. The cortex of the swollen part of the long bones was quite thin and there was striking trabecular atrophy. Both the vault and base of the skull showed marked thickening and sclerosis, leaving no interlaminal zone. It is probable that the diffuse degenerative change of the cerebral white matter with gliosis bears some resemblance to that produced by a circulatory disturbance of the great vein of Galen. Due to the narrowed foramen magnum, deformed atlase and axis, and the surrounding postoperative scar, the upper cervical cord was compressed, markedly atrophic and degenerated. Other segments of the cervical and thoracic cord displayed secondary wallerian degeneration and focal neurolytic lesions in the white matter. At the level of Th11 there was a pencil-like malacic lesion, suggesting an apparent interference of circulatory disturbance due possibly to the deformed vertebral column.

Adult↗
PubMed1984

Delayed diagnosis of a spontaneous atlanto-axial rotatory dislocation.

Without any known specific cause a 3-year-old boy developed a torticollis. Although the symptoms were treated immediately there was no improvement. Four months later X-rays showed that the dens-atlas distance was enlarged. In spite of this, he was treated by tenotomy and intensive physiotherapy, but the torticollis remained. Two years later a tomogram and a CT showed a complete rotatory dislocation between atlas and axis. At this stage it was impossible to treat the original cause. Physiotherapy was continued to improve the position of the head.

Atlanto-Axial Joint↗
PubMed1997

Pathogenesis of non-traumatic atlanto-axial subluxation (Grisel's syndrome).

Non-traumatic atlanto-axial subluxation (AAS) is an uncommon complication of upper neck inflammatory processes and head and neck surgery. It is also known under the eponym of Grisel's syndrome (GS). We present a case report of a 6-year-old boy with GS that resulted from a retropharyngeal abscess. A diagnosis was not made until 2 months after the occurrence of infection. Re-evaluation of repeated CT scans of the neck showed the sequential development of AAS. These findings implied that the pathogenesis of GS is a distention of the ligaments between the atlas and axis rather than loosening of the ligaments caused by the spread of an inflammatory edema from the soft tissues of the neck as has been proposed by others.

Atlanto-Axial Joint↗
PubMed1996

Magnetic resonance angiographic analysis of atlanto-axial rotation: anatomic bases of compression of the vertebral arteries.

The aim of this study was to identify the functional anatomic factors involved in the maintenance or disturbance of flow in the vertebral aa. during atlanto-axial rotation. Fourteen healthy volunteers were studied by magnetic resonance angiography (MRA) by a three-dimensional sequence in phase contrast centered on the vertebral aa. at the level of the cranio-cervical junction before and after left rotation of the head. A decrease in the signal intensity of the arterial flow was sought for. The results were compared to the posterolateral development of the loop of the vertebral a. in its atlanto-axial segment in neutral position, and to the measurement of the angular opening between the atlas and axis in dynamic position. Seven subjects also had a three-dimensional CT study (3D CT) of the bony relations of C1 and C2 after rotation. In 4 subjects a disturbance of flow in the right vertebral a. was observed in the transverse foramen of C2. This occurred when two factors were combined: an under-developed atlanto-axial arterial loop and a C1-C2 angle exceeding 35 degrees in maximal rotation. In the other subjects a well-developed arterial loop and/or a C1-C2 angle of less than 35 degrees in maximal rotation were factors preserving the arterial flow. The risk factor associated with the C1-C2 angle seemed correlated in 3D CT with loss of the usual asymmetric character of rotation. A clinical application is reported with a case combining chronic rotational dysfunction of the cranio-cervical junction as shown by 3D CT and complete compression of the vertebral a. in MRA, confirmed by conventional angiography. A knowledge of this physiopathologic mechanism allows clinical detection and evaluation of the risk of any effect of pathology of the cranio-cervical junction on the vertebral a.

Adolescent↗
PubMed2004

[Surgical aspects of the cervical spine in rheumatoid arthritis].

Approximately 20% percent of the patients with rheumatoid arthritis show pathology in the cervical spine. The translational instability between axis and atlas might be painful and leads in the long term to myelopathic changes due to chronic traumatization of the myelon. Ongoing osseous resorption of the lateral masses of the atlas cause upward migration of the dens into the foramen magnum. In the subaxial cervical spine, the inflammatory process causes instability and deformity. Neck pain is the most common indication for surgery, but neurological symptoms with myelopathy or radicular deficits might be the primary cause for surgery. Neurophysiological investigation is suitable to obtain objective results. Stabilization of the atlantoaxial segment is the most common procedure for treatment of atlantoaxial instability. It is performed by screw fixation technique from a posterior approach. In case of severe occipitocervical dislocation, the fixation has to be extended to the occiput. Persistent dislocation or compression by the dislocated dens has to be treated by transoral decompression. In the subaxial spine, instabilities may be treated by posterior plate fixation with lateral mass screws or pedicle screws. Concomitant nar-rowing of the spinal canal should be approached by anterior decompression with corpectomy and/or posterior laminectomy. The timing of surgery in rheumatoid patients is crucial to obtain satisfactory clinical results.

Arthritis, Rheumatoid↗
PubMed1978

Cervico-occipital pain and its surgical treatment: the myth of the bony millstones.

The proposal was made in 1949 that occipital neuritis/neuralgia was frequently of traumatic origin. The hypothesis was advanced that the C2 sensory root lay unprotected between the lateral masses of the atlas and axis and was vulnerable to squeezing on extreme extension or rotation of the head. This conjecture converted a hitherto banal neurologic affliction into the sequela of a banal trauma. Hence, it has been exploited in the diagnosis and treatment of whiplash injuries as well as for headaches of unknown origin. Evidence is presented that the original anatomic proposition was erroneous and that the C2 root is not exposed and is not vulnerable. Indeed, a survey of the "worst" traumatic and pathologic disruptions of the craniospinal junction shows that although they would be expected to injure the C2 root, in fact, they do not. The theory as well as the operations based upon it, particularly intradural section of the C2 root, should be abandoned.

Cervical Vertebrae↗
PubMed1986

Unit activity in nucleus paragigantocellularis lateralis during cerebral ischemia in the rat.

In urethane-anesthetized, paralyzed and respirated rats with both vertebral arteries ligated between atlas and axis, bilateral occlusion of the common carotids produces a 19-85 mm Hg rise in mean arterial pressure. This pressor response is entirely mediated by the activation of the sympathetic system, is unaffected by brainstem transection at midpontine levels and is completely eliminated by bilateral lesions of the anterior ventrolateral medulla (including nucleus paragigantocellularis lateralis or PGCL). The magnitude of the response is unaltered following the bilateral section of the 9th-12th cranial nerves. The pressor response is preceded by a rise (25-250%) in the rate of discharge of a specific group of 'vasomotor' neurons present in the pressor area of the PGCL which exhibit the following characteristics: axonal projection to the thoracic spinal cord, spontaneous discharges at low blood pressure, pulse-synchronous activity, discharge rate inversely related to mean arterial pressure and total inactivity above 140-160 mm Hg. It is suggested that the same population of vasomotor neurons relays the sympathoexcitation produced by cerebral ischemia to the cord and also mediates baroreceptor reflexes and generates the basal sympathetic tone.

Animals↗
PubMed1988

Moment-rotation relationships of the ligamentous occipito-atlanto-axial complex.

The relationships between applied pure moments at the occiput (C0) and the resulting rotations at the atlanto-occipital (C0-C1) and atlanto-axial (C1-C2) joints are quantified. In axial twist, with a moment of 0.3 Nm, a mean rotation of about 2.5 degrees and 23.3 degrees was observed at C0-C1 and C1-C2 units respectively. Both the atlas and axis contributed to produce lateral bending motion. The ratio between extension and flexion rotations at C0-C1 was 2.5:1. Lateral bending and axial rotations were strongly coupled to each other. The occipito-atlanto-axial complex exhibited a large 'neutral zone' compared to lower cervical spine segments. The likely clinical significance of these findings are discussed.

Aged↗
PubMed1989

Special Doppler ultrasound transducers for recording vertebral artery blood flow in rabbits.

Two kinds of transducers and a surgical procedure by means of which the vertebral artery of rabbits can be insonated through the acoustic window between atlas and axis are presented. A range-gated pulsed Doppler ultrasonic device of 10 MHz is used. Rabbit vertebral Doppler waveforms are characterized by high end-diastolic flow and a modified Pourcelot Index of 0.3. They are identical to those recorded from human vertebral arteries.

Animals↗
PubMed2005

Ossified ligamentum flavum of the atlantoaxial region.

A 30-year-old male presented complaining of a six-month history of progressive weakness and paraesthesia in all four limbs. Symptoms occurred following moderately severe neck trauma. Investigations revealed ossification of the ligamentum flavum (OLF) between the atlas and axis, with marked cord compression. The patient showed remarkable neurological recovery following excision of the OLF. OLF causing cord compression is rare and has never been reported in the atlantoaxial region.

Adult↗
PubMed1993

Transoral-transpharyngeal approach to the upper cervical vertebrae.

The classical operative approaches to the cervical spine include the posterior one and the anterior exposure along the sternomastoid muscle. However, neither of these are helpful in exposing the upper cervical vertebrae, especially the odontoid process, atlas, and axis. We have used the transoral-transpharyngeal exposure for lesions of the odontoid process and upper (first to third) cervical vertebrae in six patients. The pathologic processes included rheumatoid disease and fracture of the cervical vertebrae, suspected tumor with compression of the spinal cord, basilar invagination, and compression of the medulla. In all six patients, the exposure was excellent, and postoperative morbidity was minimal. Tracheostomy was performed routinely in all these patients. In five patients, vertebral stabilization was performed as a secondary procedure a few days after the initial anterior decompressive surgery. The transoral-transpharyngeal approach appears to be relatively easy. It is associated with minimal complications and provides excellent exposure of the odontoid and upper cervical vertebrae for a microneurosurgical approach. Modifications of this approach include incision of the soft palate, excision of a portion of the hard palate, and, occasionally, transmandibular median labio-mandibulo-glossotomy (Trotter's) approach. Although the technique was described initially approximately 35 years ago, this neglected anatomic approach will facilitate cooperative efforts between head and neck surgeons and neurosurgeons.

Adult↗
PubMed2000

Decapitation in suicidal hanging--a case report with a review of the literature.

We report a case of self-decapitation by suicidal hanging from a river bridge and discuss the decapitation mechanism, reviewing the literature. The torso and the head of the victim, respectively, were found apart in a river approximately 100 m and 600 m, respectively, downstream from the bridge in two days. Morphological, serological and DNA analyses confirmed their identity. Torn ligaments between the atlas and axis accompanied by fractures in the axis at the partes interarticulares were indicative of a traction force combined with anteroflexion of the head by falling from a height, and the radial pressure due to a strong, single twisted nylon rope with a slip knot was considered to have contributed considerably to the subsequent skin laceration with wavy marginal abrasions. In the reviewed literature, cervical spine fractures were described only in two of six cases, suggesting head movement at the time of decapitation.

Journal Article↗
PubMed1996

A new hypothesis for sudden infant death syndrome: the occlusion of vertebral arteries as a major cause.

Many factors, such as prematurity, low weight and minor infection, may predispose to Sudden Infant Death Syndrome (SIDS) but not cause it. It is suggested that the ultimate act of dying is due to the occlusion of one or both vertebral arteries triggered by the position of the head and cervical spine. When the head is turned to one side, the ipsilateral vertebral artery may be occluded at mid-cervical level along its length, or the contra lateral artery at atlanto-axial level or on both sides with the head in the initial position. Extension of cervical spine, with or without rotation, may produce obstruction of one or both vertebral arteries. If the degree, the levels and duration of occlusion are exceeded, particularly if there is a degree of failure of the collateral circulation (including one from carotid arteries via posterior communicating arteries), this can lead to prolonged apnoea, a 'near-miss' or cot death. The factors which may predispose to SIDS among others are hypoplasia or 'unexercised' vertebral arteries (in utero) and/or hypermobility of the immature cervical spine with lax joint capsules and ligaments. These factors allow the undue stretch or kinking of the vertebral arteries resulting in occlusion when the head or cervical spine are turned. The hypothesis explains the reduction of mortality of SIDS in infants in sleeping supine position to those in the prone position. In prone position, the infant's head is rotated 90 degrees which may put stress on atlas and axis thus occlude vertebral arteries by stretching and kinking. Infants under 6 months are unable to change position unaided so duration of obstruction is an aggravating element. These factors are about 50% less in the supine position.

Journal Article↗
PubMedDate not supplied

A new system of classification for spinal injuries.

BACKGROUND CONTEXT: A comprehensive classification for spinal trauma has proved difficult to achieve as attested to by the number of systems in use today. In addition, few systems can be applied to all levels of the spine, and the first two cervical vertebrae are usually treated as altogether separate from the remainder of the spine. Consequently, outcome data and comparison of published data are difficult, at best. PURPOSE: The purpose of this presentation is to introduce a new system for classification of spine trauma applicable to all levels of the spine. STUDY DESIGN/SETTING: A different way of viewing the vertebrae is proposed. It allows the inclusion of all levels of the spinal column in a unified classification system based on the morphology of the injury. Each vertebra is viewed as a bony ring, and the rings are linked, above and below, by three osseoligamentous structures. These are the end plate-disc-end plate anteriorly and the facet joints posteriorly. Equivalent structures for the links are defined for the atlas and axis. PATIENT SAMPLE: The x-rays and computed tomographic or magnetic resonance imaging of patients with spine trauma were used to apply this classification to acute injuries. The sample used was all patients with spine trauma admitted, during a 1-year period, to a level 1 trauma center. Not all the patients were treated by the author, and no attempt was made to determine indications for treatment or treatment outcomes on the basis of this new classification system. METHODS: A new classification retrospectively applied to a defined patient population, which appeared to be representative of known trauma patterns. RESULTS: All patients with spinal trauma in this patient population were classifiable by this new system. All fracture types proposed in this system were represented in the patient sample. CONCLUSION: This new classification system appears to warrant further study.

Cervical Vertebrae↗
PubMed1989

Are "cervicogenic" headaches due to myofascial pain and cervical spine dysfunction?

The purpose of this investigation was to evaluate whether the pain of cervicogenic headache could be due to referred symptoms from myofascial trigger points. The presence or absence of cervical spine dysfunction was also of interest. Eleven patients with cervicogenic headaches were systematically examined for myofascial trigger points and cervical spine dysfunction. All patients had at least three myofascial trigger points on the symptomatic side. In eight of these patients, trigger point palpation clearly reproduced their headache. There were 70 myofascial trigger points (35 "very tender", 35 "tender") and 17 non-myofascial tender points on the symptomatic side, compared to 22 myofascial trigger points (one "very tender", 21 "tender") and 19 non-myofascial tender points on the asymptomatic side. These differences were statistically significant [chi-square (2df) = 22.04, p less than 0.0001]. All patients had some evidence of cervical dysfunction. Ten patients (91%) had specific segmental dysfunction of occiput on atlas and/or atlas on axis. Five patients were entered into a non-invasive, interdisciplinary pain management program designed to treat cervical spine dysfunction and myofascial pain. Treated patients reported a significant decrease in the frequency and intensity of their headaches during a median two-year follow-up. It is concluded that myofascial trigger points may be an important pain producing mechanism in cervicogenic headache and that segmental cervical dysfunction is a common feature in such patients. Conservative, non-surgical treatment appears to be effective in reducing the frequency and intensity of cervicogenic headache. These data suggest that surgical approaches should be reserved only for those patients who fail conservative therapy.

Adult↗