Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ATLAS”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 253 records · Page 14Linked to original sources
PubMed1979

Unsuspected atlas fracture and instability associated with oropharyngeal injury: case report.

A case of oropharyngeal injury associated with an unsuspected direct atlas anterior arch fracture is presented. Instability at the occipito-atlanto-axial joints developed because of the coexistence of a rather common congenital defect of the posterior atlas arch. Awareness of the frequency of congenital atlas anomalies and the possibility of direct cervical spine injury with pharyngeal trauma will aid early recognition of this problem and allow early effective treatment.

Adolescent↗
PubMed1999

Occipital pain in osteoid osteoma of the atlas. A report of two cases.

STUDY DESIGN: Two cases of occipital pain caused by an osteoid osteoma of the atlas are presented. OBJECTIVES: To describe the management of occipital pain in two young patients. SUMMARY OF BACKGROUND DATA: Osteoid osteoma is a benign lesion mostly affecting the long bones. A spinal location is uncommon. To the authors' knowledge, there are only five other reports of an osteoid osteoma located in the atlas. METHODS: Occipital headache, which was relieved by salicylates, was the major symptom reported by the two adolescents. In the first patient, a lesion of C1 was seen on plain radiographs. In the second patient, the diagnosis of osteoid osteoma was suggested by scintigraphic imaging and subsequently by computed tomography. RESULTS: Pain disappeared in both cases after surgical excision of the lesion. Histologic examination disclosed characteristic features of osteoid osteoma. CONCLUSIONS: Occipital pain in adolescents, which is relieved by aspirin, should raise suspicion about the possibility of an osteoid osteoma of the atlas. If standard cervical spine radiographs are negative, isotope scanning and computed tomography can help to establish the diagnosis. Complete excision eliminates the lesion and produces immediate relief for the patient.

Adult↗
PubMed2000

Synovial cyst of the transverse ligament of the atlas in a patient with os odontoideum and atlantoaxial instability.

STUDY DESIGN: A case report and review of the literature. OBJECTIVE: To describe the diagnosis and successful treatment of a synovial cyst arising from the transverse ligament in a patient with os odontoideum and atlantoaxial instability. SUMMARY OF BACKGROUND DATA: Synovial cysts arising from the transverse ligament of the atlas are extremely rare. Development of a synovial cyst is thought to be attributable to degenerative changes of the C1-C2 facet joints or to microtrauma. Direct excision of the cyst is the only treatment cited in previous reports. METHODS: A synovial cyst arising from the transverse ligament of the atlas in a 45-year-old man with os odontoideum and atlantoaxial instability was treated surgically with posterior atlantoaxial fusion alone. The magnetic resonance images, surgical treatment, and related literature are reviewed. RESULTS: Preoperative magnetic resonance images of the cervical spine showed a large cystic mass located ventral to the cord arising at the level of the transverse ligament of the atlas: the mass was of low signal intensity on T1-weighted images, was of high signal intensity on T2-weighted images, and was enhanced marginally with gadolinium-DTPA on T1-weighted images. Spontaneous regression of the cyst was identified on the follow-up magnetic resonance images taken 3 months after C1-C2 posterior wiring and fusion. CONCLUSIONS: A patient with a synovial cyst arising at the C1-C2 junction ventrally at the level of the transverse ligament showed spontaneous regression of the lesion after C1-C2 posterior wiring and fusion.

Atlanto-Axial Joint↗
PubMed2003

Congenital partial aplasia of the posterior arch of the atlas causing myelopathy: case report and review of the literature.

STUDY DESIGN: A case report of a patient with a congenital anomaly of the posterior arch of the atlas and review of the literature are reported. OBJECTIVE: To describe a unique presentation of cervical myelopathy caused by a mobile isolated bone fragment in an otherwise healthy young male. The description is supplemented by a video showing the repeated trauma the bone fragment caused to the dorsal spinal cord with neck extension. SUMMARY OF BACKGROUND DATA: Congenital anomalies of the posterior arch of C1 are well described and are almost always asymptomatic and found incidentally. Neurologic symptoms, either of a chronic nature or developing acutely following head or neck trauma, have been described in patients with isolated posterior arch tubercles (Types C or D). METHODS: A 17-year-old male developed sensory deficit in his distal lower extremities acutely that progressed over several weeks proximally and into his left upper extremity. He also described a Lhermitte sign, only with extension of his neck and an episode of temporary quadriparesis with a minor fall. Plain radiographs and a computed tomography scan of his neck revealed a congenital deformity of the posterior arch of the atlas. Magnetic resonance imaging showed T1 and T2 signal abnormality within the posterior spinal cord at the level of C1 to C2. RESULTS: The patient underwent flexion and extension movements under fluoroscopy, which showed the posterior tubercle moving anteriorly and compressing the spinal cord every time he extended his neck. The fragment was resected, and, intraoperatively, dense fibrous tissue was found to be bridging the bony defect. After surgery, his sensory deficits almost completely resolved, and he no longer had a Lhermitte phenomenon. CONCLUSION: This case illustrates a symptomatic congenital deformity of the posterior arch of the atlas due to a mobile, isolated fragment. These anomalies are exceedingly rare. To date, only 17 patients, including ours, have been described in the literature as having myelopathy related to an isolated posterior tubercle. Of these, only two patients had documented movement of this tubercle before our report. Recognizing the anomaly is crucial because treatment is relatively simple, produces resolution of symptoms, and prevents major neurologic deficits from occurring after trauma.

Adolescent↗
PubMed2026

MAdLandExpression: integrating sexual reproduction into the Physcomitrium patens expression atlas.

Physcomitrium patens is a bryophyte model system particularly valuable for evolutionary developmental and comparative genomics studies. Sexual reproduction in bryophytes offers unique insights into the evolution of land plant reproduction. Unlike seed plants, bryophytes have a dominant gametophyte phase and provide significant advantages for studying sexual reproduction, such as the possibility to maintain embryo-lethal mutants through vegetative propagation or the presence of motile male gametes. More than 25 years after the first publications of transcriptomic data for P. patens, expression data of most developmental stages of P. patens as well as its responses to various biotic and abiotic perturbations have been represented by microarrays or RNA-seq datasets. To facilitate the use of such data, we introduce the MAdLandExpression atlas as a successor of PEATmoss (Physcomitrium Expression Atlas Tool), integrating its 109 P. patens expression experiments and expanding it with 20 recently published RNA-seq samples of sexual reproduction stages, thus completing the coverage of the P. patens life cycle. The MAdLandExpression atlas also introduces new features for data visualization and analysis, such as the comparison of samples from multiple datasets and gene set normalization. Using this tool, the sexual reproduction dataset was analyzed, identifying genes potentially important for egg and sperm cell development, and confirming the behavior of known key genes in sexual development observed in previous studies.

Bryopsida↗
PubMed1977

Pain arising in the posterior arch of the atlas.

Headache of cervical origin is by no means an adequate diagnosis. The exact mechanism has to be established for the case in question. A type of cervical headache which arises from the posteriorr arch of the atlas is described. The basic finding is tenderness of this structure on palpation; the technique of palpation is described. In a majority of cases movement restriction (blockage) between the occiput and the atlase is found. The headache as described by the patient is not characteristic, migrainous attacks being present in about one-third of the cases. A frequent feature is pain on retroflexion of the head. Treatment consists of manipulation of the blockage, and infiltration or needling of the posterior arch of the atlas if there is no blockage or if pain continues after the restoration of mobility. In the more complicated cases remedial exercise is indicated. Experience with 64 cases is described.

Atlanto-Occipital Joint↗
PubMedDate not supplied

Unilateral demonstration of the atlas in ipsilateral maxillary alveolar bone destruction.

In conventional sinus films in occipito-frontal projection, the atlas is superimposed on the maxillary alveolar processes. If destruction of the alveolar process is present, the atlas-half on the affected side may be unusually clearly demonstrated. The value of this 'unilateral demonstration of the atlas' was confirmed by comparing a group of 20 patients with alveolar process destruction with two groups of 50 patients, one reported as normal and another with mucosal thickening, fluid levels or entirely dense sinuses.

Aged↗
PubMed1994

Reconstruction of the hypoplastic posterior arch of the atlas with calvarial bone grafts for posterior atlantoaxial fusion: technical report.

Posterior atlantoaxial fusion is a common procedure performed for instability at C1-C2. This operation requires intact posterior elements of both the atlas and the axis. When this is not the case, the incorporation of the occiput and the lower spinal segments is usually required for adequate posterior fusion, but such a procedure limits the mobility of the upper cervical spine. A technique for the reconstruction of the posterior arch of the atlas with calvarial bone is described in this report. This technique allowed the successful fusion of the C1 and C2 vertebrae in a patient with traumatic atlantoaxial subluxation who also had a congenital absence of the posterior arch of the atlas.

Atlanto-Axial Joint↗
PubMed1998

Ossification of transverse ligament of the atlas associated with atlanto-axial dislocation--case report.

A 68-year-old male presented with progressive quadriparesis. Twelve years previously he had undergone anterior decompression with bone grafting for cervical ossification of the posterior longitudinal ligament associated with spinal trauma. Radiological examination showed ossification of the transverse ligament of the atlas (TLA) and severe stenosis of the upper cervical canal. Anterior dislocation of the atlas was also present, but the occiput/atlas/axis unit was perfectly stable due to the prior anterior fusion. Suboccipital decompression and laminectomy of the atlas were performed, and his symptoms improved. Based on the atlanto-axial dislocation, the TLA might have been damaged at the time of the primary trauma and became the trigger for the ossification of the TLA, showing that marked ossification of a vertebral ligament can occur after injury.

Aged↗
PubMed2006

Atlas hypoplasia associated with non-traumatic retro-odontoid mass.

A 38-year-old man presented with progressive cervical myelopathy due to atlas hypoplasia associated with non-traumatic retro-odontoid mass. The neuroimaging findings suggested hypertrophy of the transverse ligament of the atlas. No histological confirmation of the retro-odontoid mass was obtained. Clinical manifestations improved after posterior decompression. Decompressive laminectomy of the atlas with or without fusion can achieve a good outcome in such cases.

Adult↗
PubMed1979

Two features of the atlas vertebra simulating fractures by tomography.

The bipartite superior joint surface and the pseudonotch of the atlas, although well described in anatomic and radiologic literature, may be mistaken for fractures by tomography. The first may appear as a trough on the superior articular surface of the lateral mass of the atlas. The second, the normal tubercle for insertion of the transverse ligament of the atlas, may look like a separate ossicle or a chip fracture.

Cervical Atlas↗
PubMed1993

Occipital-axis posterior wiring and fusion for atlantoaxial dislocation associated with occipitalization of the atlas. Technical note.

The authors present their technique of occipital-axis posterior wiring and fusion for atlantoaxial dislocation associated with an occipitalized atlas. The technique consists of drilling a 3 x 1-cm horizontal groove in the occipital bone 1 cm posterior to the foramen magnum and building up a bony bridge along the posterior margin of the foramen magnum. This bony bridge is referred to as an "artificial atlas." Conventional wiring and fusion is performed between the artificial atlas and the C-2 lamina, interposing a strut bone graft. Since the compression force on tightening the wire is vertical, a very high degree of stability for the occipital-C-2 complex is achieved, facilitating early mobilization without postoperative redislocation.

Atlanto-Axial Joint↗
PubMed2001

Posterior bridging of the atlas vertebra in south Indians.

The vertebral artery is vulnerable to compression in its course between foramen transversarium and the foramen magnum during extreme rotation of the head and neck. This situation may be aggravated by the presence of posterior or lateral bridge of the atlas and result in compromised blood flow. The incidence of the bony ring formed by posterior bridging has been demonstrated in atlases of various races across the world: it varies between 1.875% to 29.2%. In an examination of sixty south Indian atlases it was found in 11.7% of the cases. The presence of this bony bridging should be taken in to account during a surgical manipulation of the cervical spine.

Adult↗
PubMed2005

[A case of giant cell tumor in atlas].

We report a rare case of giant cell tumor in the atlas. A 50-year-old female presented with severe pain in her right neck and shoulder. The preoperative magnetic resonance images showed a tumor mixed with solid and cystic components in the right side of the atlas. CT scan showed that the anterior and posterior arches of the atlas were destroyed. Preoperative biopsy led to the pathological diagnosis of giant cell tumor with multinuclear giant cells and mononuclear stromal cells. A preoperative vertebral angiogram demonstrated tumor stain supplied from the muscular branches. To reduce intraoperative bleeding, the embolization of the right vertebral artery by GDC was performed before surgical removal. The tumor was subtotally removed following ligation of the right external carotid artery to reduce bleeding of tumor. We used the Olerud cervical system to prevent cervical instability after resection of the tumor. Although the symptoms disappeared completely after surgery, regrowth of tumor was observed in follow-up MRI 4 months after the operation. For this reason, local radiation therapy was performed (50 Gy). Then, the size of the tumor has not changed in the 1.5 years since the operation.

Cervical Atlas↗
PubMed1991

Pseudonotch of the atlas vertebra simulating fracture with computed tomographic diagnosis. A case report.

Pseudonotch of the atlas represents a normal variation of the atlas related to a notched protuberance of the medial surface of its lateral masses. A case is presented in which cervical spine roentgenography revealed a prominent pseudonotch that mimicked a fracture of the lateral masses of the atlas. Minimal rotation of C-1 on C-2 was present without apophyseal joint subluxation. Computed tomography imaging provided an accurate diagnosis.

Adult↗
PubMed1990

Postnatal ossification centers of the atlas and axis in miniature schnauzers.

Postnatal ossification of the atlas and axis was studied in Miniature Schnauzers by examining alizarin-stained bone clearings, cleaned dry bones, radiographs, histologic sections, and arterially perfused bone clearings. Sixty-two pups (1 day to 16 weeks old) and 4 adults were examined. In 1-day-old pups, the atlas consisted of 3 separate ossification centers: a left and right neural arch center and midventrally, the intercentrum 1, which formed the body of the atlas. The axis contained 4 separate ossification centers: a left and right neural arch center; centrum 2 in the main part of the axis body; and centrum 1, which formed the caudal part of the dens and the cranial part of the axis body. By 6 weeks of age, the epiphysis on the caudal end of the axis body had begun to ossify. At this time, the intercentrum 2, which developed as a cuboidal ossification center intercalated between centrum 1 and centrum 2 in the middle of the cranial half of the axis body, also began to ossify. The centrum of the proatlas, which formed the apex of the dens, was first seen ossified in a 9-week-old pup. These 10 ossification centers were seen as constant and separate elements. In all dogs, the dens developed from 2 separate ossification centers: the centrum of the proatlas formed the cranial one-quarter, and centrum 1 formed the caudal three-quarters. Dens dysplasia is unlikely to be a result of failure of development of one of the ossification centers for the dens.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1990

[Gene geography of human population: computer-generated regional genogeographic atlas].

Gene geography is considered in this work as the instrument for analysis of population's gene pool. To be effective in this analysis, gene geography should move from mapping of gene frequencies for each gene (and phenes) to construction of genogeographical atlas, as a collection of maps generated by computer, following some strongly defined principles and methods, and joined together, according to general task and the programme of investigation. Brief version of regional genogeographical atlas of Mongolians and the other peoples of Central Asia is presented in the article. This atlas includes computer-generated maps of AB0, Hp, Gc, G'3, Tf, GLO, EstD and PGM1 gene frequencies as well as computer-generalized maps of Mongolian gene pool.

Atlases as Topic↗
PubMed1989

Atlantoaxial subluxation and absence of transverse ligament of the atlas in a dog.

Absence of the transverse ligament of the atlas was diagnosed at necropsy in an 8-month-old Shih Tzu with radiographic signs of atlantoaxial subluxation. Symmetric ataxia, tetraparesis, and signs of pain in the vertebral canal suggested a lesion in the cervical portion of the spinal cord. Necropsy revealed absence of the transverse ligament of the atlas and malformation of dens and atlas. In addition, the alar ligaments were distinct and thick, and the atlanto-occipital and atlantoaxial joint capsules were markedly thicker than normal. Histologic examination revealed focal compressive myelopathy of the spinal cord at the level of the atlantoaxial joint.

Animals↗