Cervical vertebral body fusions in patients with skeletal deep bite. (41/126)

Cervical column morphology was examined in 41 adult patients with a skeletal deep bite, 23 females aged 22-42 years (mean 27.9) and 18 males aged 21-44 years (mean 30.8) and compared with the cervical column morphology in an adult control group consisting of 21 subjects, 15 females, aged 23-40 years (mean 29.2 years) and six males aged 25-44 years (mean 32.8 years) with neutral occlusion and normal craniofacial morphology. None of the patients or control subjects had received orthodontic treatment. For each individual, a visual assessment of the cervical column and measurements of the cranial base angle, vertical craniofacial dimensions, and morphology of the mandible were performed on a profile radiograph. In the deep bite group, 41.5 per cent had fusion of the cervical vertebrae and 9.8 per cent posterior arch deficiency. The fusion always occurred between C2 and C3. No statistically significant gender differences were found in the occurrence of morphological characteristics of the cervical column (females 43.5 per cent, males 38.9 per cent). Morphological deviations of the cervical column occurred significantly more often in the deep bite group compared with the control group (P < 0.05). Logistic regression analysis showed that the vertical jaw relationship (P < 0.05), overbite (P < 0.001), and upper incisor inclination (P < 0.01) were significantly correlated with fusion of the cervical vertebrae (R(2) = 0.40).  (+info)

Duraplasty in the posterior fossa using a boat-shaped sheet of expanded polytetrafluoroethylene. (42/126)

Application of sutures between expanded polytetrafluoroethylene (ePTFE) dural substitutes and the dura mater is often frustrating in posterior fossa surgery because of the difficulty in holding the elastic graft in a deep and narrow field. To resolve this problem, we have developed a boat-shaped graft made from a triangular ePTFE sheet by pinching each angle using a suture. Formation of standing edges of the sheet facilitates holding of the flaps for secure and more rapid suturing than the conventional approach using a flat sheet.  (+info)

Screw fixation via diploic bone paralleling to occiput table: anatomical analysis of a new technique and report of 11 cases. (43/126)

Several types of posterior approaches have been adopted for occipitocervical fusion. Prior to this study, Foerater et al. in 1927 used a fibular strut graft in the site between the occiput and the lower cervical spine to achieve fusion. Since then, various techniques including wrings, Hartshill loop, AO reconstructive plate, and AXIS occipital plate were described and used widely. As far as we know, all these techniques involve the screw placement vertical to the diploic bone; however none has ever addressed the feasibility of screw placement in occiput parallelling to the diploic bone. In our study, 30 dry specimens of human occiputs were measured manually using vernier calipers and protractors. The intradiploic screw was first supposed to be inserted inferiorly to the superior nuchal line (SNL) prominence. The entry point located at the superior edge of the SNL prominence. Afterward, the measurements of extracranial occiput in SNL area on midline and bilateral 15 mm to the midline saggital-cutting planes of the occiput were conducted. The thickness of the occipital bone at the location of SNL prominence, the entry point, the exit point and the screw orientation were measured, respectively. Afterward, 11 patients with craniocervical malformation were treated surgically using this alternative and their X-ray radiographs and CT scans were evaluated postoperatively. The data showed that the occipital at the site of SNL prominence was the thickest. The thickest point was external occipital protuberance (EOP), which was up to 14 mm. The thickness decreased gradually from the site of SNL to the superior border of surgical decompressed area. The actual length of screw channel was about 26 mm. The mean thickness for safe screw insertion ranged from 5.73 to 14.14 mm. A total of 22 intraocciput screws parallel to diploic bone were placed precisely, without injury to the cerebral and inner occipital venous sinus. The results confirm that occiput is available for holding intraocciput screw paralleling to diploic bone.  (+info)

Arcuate foramen of atlas: incidence, phylogenetic and clinical significance. (44/126)

Arcuate foramen is less known trait of the human atlas vertebra formed by a delicate bony spiculum, which arches backward from the posterior end of the superior articular process. Examination of 1044 human atlas vertebra revealed that the trait was present in 13.8% of the samples. The mean length of the arcuate foramen form was 7.16 mm on the left side and 9.99 mm on the right side in bilateral positive samples while it was 8.14 mm and 9.26 mm respectively in unilateral positive samples. The mean vertical height of this foramen was 6.57 mm on the left side and 6.52 mm on the right side in bilateral positive samples while it was 4.91 mm and 5.38 mm respectively in unilateral positive samples. The sides did not show any statistical significant differences. The importance of the arcuate foramen lies in the external pressure it may cause on the vertebral artery as it passes from the foramen transversarium of the first cervical vertebra to the foramen magnum of the skull.  (+info)

Cervical myelopathy caused by soft-tissue mass in diffuse idiopathic skeletal hyperostosis. (45/126)

A rare case of cervical spinal cord compression in diffuse idiopathic skeletal hyperostosis (DISH or Forestier's Disease) caused by a craniocervical mass of soft-tissue is reported. The objective is to describe an uncommon mechanism of spinal cord compression in DISH. Three weeks after a cardiac infarction a 69-year-old man slowly developed spastic tetraparesis. Magnetic resonance tomography showed a craniocervical tumor compressing the spinal cord and a massive DISH of the cervical spine. An extended mass of yellowish amorphous material was removed from between the dura, the posterior odontoid process and the posterior aspect of vertebral body C2 reaching to the upper part of C3.The histologic appearance indicated connective tissue and cell-degenerated cartilaginous tissue. There was no inflammatory component and no evidence of neoplasia. No ossification of the posterior longitudinal ligament (OPLL) was found. After removal and craniocervical stabilization the patient's neurologic function improved remarkably. The increase of mechanical stress on the atlantoaxial segment and enhanced proliferation reaction of the connective tissue in DISH are suggested as the underlying pathomechanisms in the formation of this soft-tissue mass.  (+info)

Retropharyngeal pseudomeningocele formation as a traumatic atlanto-occipital dislocation complication: case report and review. (46/126)

Retropharyngeal pseudomeningocele after atlanto-occipital dislocation is a rare complication, with only five cases described in the literature. It develops when a traumatic dural tear occurs allowing cerebrospinal fluid outflow, and it often appears associated with hydrocephalus. We present a case of a 29-year-old female who suffered a motor vehicle accident causing severe brain trauma and spinal cord injury. At hospital arrival the patient scored three points in the Glasgow Coma Scale. Admission computed tomography of the head and neck demonstrated subarachnoid hemorrhage and atlanto-occipital dislocation. Three weeks later, when impossibility to disconnect her from mechanical ventilation was noticed, a magnetic resonance imaging of the neck showed a large retropharyngeal pseudomeningocele. No radiological evidence of hydrocephalus was documented. Given the poor neurological status of the patient, with spastic quadriplegia and disability to breathe spontaneously due to bulbar-medullar injury, no invasive measure was performed to treat the pseudomeningocele. Retropharyngeal pseudomeningocele after atlanto-occipital dislocation should be managed by means of radiological brain study in order to assess for the presence of hydrocephalus, since these two pathologies often appear associated. If allowed by neurological condition of the patient, shunting procedures such as ventriculo-peritoneal or lumbo-peritoneal shunt placement may be helpful for the treatment of the pseudomeningocele, regardless of craniocervical junction management.  (+info)

Solitary juvenile xanthogranuloma in the upper cervical spine: case report and review of the literatures. (47/126)

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Spontaneous rotatory atlantoaxial dislocation without neurological compromise in a child with Down syndrome: a case report. (48/126)

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