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S Ebara

Publications and source records attributed to S Ebara.

69 records · Page 4Linked to original sources
PubMed1991

Cineradiographic motion analysis of atlantoaxial instability in os odontoideum.

Cineradiography was used to study six patients with os odontoideum. Atlantoaxial kinematics was analyzed with the relative motion of the atlas on the axis. In all cases, the tracing of the anterior arch was straight in the sagittal plane, whereas the posterior arch moved in two different configurations: straight and S-shaped. In cases of S-shaped configurations, the anterior translation occurred in the neutral position. Such translation could threaten the stability of the atlantoaxial complex fixed with posterior wiring because circumferential wires allow the laminas to rotate in the sagittal direction. In patients with os odontoideum, pathomechanics of the atlantoaxial joint should be examined with cineradiography in order biomechanically to determine the soundest fixation.

Adolescent↗
PubMed1990

Increased microvascular permeability and lesion formation during gastric hypermotility caused by indomethacin and 2-deoxy-D-glucose in the rat.

The relationship between lesion formation, gastric motility, and vascular permeability was examined in rats using indomethacin and 2-deoxy-D-glucose (2DG). Both indomethacin (25 mg/kg s.c.) and 2DG (100 mg/kg/h i.v.) produced gastric hypermotility and induced lesions, mostly confined to the rugal crests of the mucosal folds; the onset of hypermotility preceded appearance of the lesions in both cases. The mucosal microvascular permeability as determined by the amount of extravasated dye (Evans blue) was increased in response to these two agents, and the permeability responses also preceded appearance of the lesions. Both the increased vascular permeability and the severity of lesions were significantly reduced when the hypermotility was inhibited by pretreatment with atropine (3 mg/kg s.c.). The severity of the lesions were also markedly reduced or worsened, respectively, by hydrocortisone (10 mg/kg s.c.) or N-ethylmaleimide (10 mg/kg s.c.) at the doses that significantly decreased or enhanced the vascular permeability responses caused by indomethacin and 2DG. These results suggest that the enhanced gastric motility as induced by indomethacin and 2DG may cause microcirculatory disturbances in the specific sites of the mucosa (mucosal folds), probably by abnormal compression of the gastric wall, leading to the increased microvascular permeability and cellular damage.

Animals↗
PubMed1990

Motion analysis of the cervical spine in athetoid cerebral palsy. Extension-flexion motion.

Frequently instability and premature onset of spondylosis of the cervical spine are found in athetoid cerebral palsy (CP) patients. These structural abnormalities appear to be related to athetoid motion of the neck in CP. Through motion analysis, the authors aimed to clarify the abnormalities of cervical motion that could precipitate structural abnormalities. The gross characteristic feature of cervical motion in athetoid CP is "whip movement." Both velocity and acceleration during extension-flexion motion were greater than in normal subjects, especially at the upper cervical levels. Also, a sudden increase in velocity and acceleration occurred during rapid motions at certain levels, followed by a larger range of motion of the cervical spine. Such kinematic abnormalities were thought to generate a greater shearing force and bending moment exerted on the corresponding cervical articulations-discs and facets. Olisthetic instability often accompanied disc degeneration at the upper cervical levels. A large range of extension--flexion motion of the cervical spine, analogous to a cantilever, caused a repeated bending moment of extraordinary magnitude and was regarded as a precipitative factor for disc degeneration and osteophytosis common at the middle and lower levels of the disc.

Adult↗
PubMed1990

Lateral rhachotomy for thoracic spinal lesions.

Capener's "Lateral Rhachotomy" was modified by additional excision of the pedicle, articular facets, part of the lamina, and a posterior half of the vertebral bodies on one side through a transpleural approach to the thoracic spine, and a retroperitoneal approach to the lumbar spine. The aim was to excise a space-occupying lesion, which exists in front of the thoracic or lumbar spinal cord, safely. This modification enable the authors to expose more than 50% of the spinal canal, and decompress it from its anterior, lateral, and posterior compressing mass. The utmost important point of this procedure is the excision of the lesion under the direct visualization of the dura. In ossification of the posterior longitudinal ligament (OPLL), the dura is usually indented by the thick bony mass, and the lesion extends over a few segment with adhesion. Using "Modified Lateral Rhachotomy," it was possible to explore three or four vertebral levels in continuity through the same skin incision. In the present report, the authors described their "Modified Lateral Rhachotomy" procedure, and reviewed the case material.

Female↗
PubMed1989

Unstable cervical spine in athetoid cerebral palsy.

The manifestations and pathomechanism of cervical instability of the athetoid neck in cerebral palsy (CP) patients was clarified in this study by means of static and dynamic x-ray analysis. Instability was defined as follows: 1) listhesis indicating anterior or posterior slip of more than 3 mm and/or 2) sagittal rotation between two vertebrae beyond the normal range measured by Penning. Cervical instability fitting this definition mainly took place in the upper and middle cervical disc levels, such as C3-4, C4-5, and/or occasionally C5-6. These coincide with the disc levels adjacent to the apex of the lordotic curve and/or those around the transitional vertebrae between the two reversed curves that render the cervical spine S-shaped in athetoid CP. A large facet angle at the apex vertebra facilitated anterior and/or posterior listhesis of the vertebrae. Conversely, a sudden decrease in the facet angle around the transitional vertebra in S-shaped curves precipitated deflection of the spine and increased sagittal rotation at this level. In addition to these structural abnormalities, rapid and repetitious neck movements seemed to accelerate the progression of cervical instability in athetoid CP patients.

Athetosis↗
PubMed1989

The prognosis of surgery for cervical compression myelopathy. An analysis of the factors involved.

We have studied the morphometry of the spinal cord in 50 patients with cervical compression myelopathy. Computed tomographic myelography (CTM) showed that the transverse area of the cord at the site of maximum compression correlated significantly with the results of surgery. In most patients with less than 30 mm2 of spinal cord area, the results were poor; the cord was unable to survive. Several factors, such as chronicity of disease, age at surgery and multiplicity of involvement are said to influence the results of surgery, but the transverse area of the cord at the level of maximum compression provides the most reliable and comprehensive parameter for their prediction.

Adult↗
PubMed1988

Myelopathy hand characterized by muscle wasting. A different type of myelopathy hand in patients with cervical spondylosis.

While the authors have often observed the hand presenting spastic dysfunction and deficient pain sensation in patients with cervical compression myelopathy, which has been termed "Myelopathy hand," they have occasionally seen a different type of myelopathy hand characterized by muscle wasting and motor dysfunction in patients with cervical spondylosis. This type of myelopathy hand they have termed "amyotrophic type of myelopathy hand." Because it is similar to the hand of a patient suffering from motor neuron disease, and yet is treatable, the authors thought it worthwhile to report this type of hand in detail. The main clinical features are localized wasting and weakness of the extrinsic and intrinsic hand muscles, but not accompanied by either sensory loss or spastic quadriparesis. For an accurate diagnosis, attention should be paid to the narrow anteroposterior (AP) canal diameter of the cervical spine (less than 13mm), multisegmental spondylosis in C5-6 and C6-7 disc levels and a reduced transectional area of the spinal cord at the C7, C8, or T1 spinal cord segments. To date the authors have seen 15 patients with this hand; seven underwent either spondylectomy or laminoplasty. In six patients who were satisfied with surgical results, recovery from muscle wasting and weakness was seen.

Electromyography↗
PubMed1988

Prosthetic replacement surgery for cervical spine metastasis.

Since 1972, 18 patients suffering from metastatic cancer in the cervical spine were treated with prosthetic replacement surgery. The surgery enabled the authors to decompress the spinal cord and the nerve roots and at the same time restore stability in the affected spine. Patients suffering from severe pain and spinal cord and/or nerve root compression secondary to involvement of a single vertebral body particularly benefited from this surgery. The rates of positive recovery were as follows: 94.1% for pain relief, 91.7% for motor recovery, and 87.5% for ambulation. The surgical efficacy was maintained until the terminal stage. Tumor recurrence took place in five cases--two anterior, and three posterior. Anterior recurrence caused a marked instability, whereas posterior recurrence did not affect stability.

Cervical Vertebrae↗
PubMed1988

Morphometry of the cervical spinal cord and its relation to pathology in cases with compression myelopathy.

The purpose of this study was to determine whether or not computerized tomography myelography (CTM) gave an actual size and shape of the cervical spinal cord, and whether such dimensions reflected pathology of the spinal cord in cases suffering from compression myelopathy. Spinal cord transverse area and compression ratio (sagittal diameter divided by transverse diameter) were measured as indicators of spinal cord morphology. As a basis for this study, we first performed CTM of cadaveric cervical columns and compared the actual dimensions of the spinal cord of the cadaveric specimens with the CTM image. Second, the correlations between these dimensions and pathology of the affected spinal cord were investigated. The results showed that CTM provided a precise image of the actual cross-section of the spinal cord. In 12 cadaveric specimens of cervical myelopathy examined, the transverse area and compression ratio were in good correlation with the severity of observed pathological changes.

Aged↗
PubMed1988

Repair of mucosal damage induced by ethanol in the rat stomach. Effects of concentration, exposure period and prostaglandins.

We investigated the relationship between the severity of acute injury and the rapidity of mucosal repair in stomachs of anesthetized rats, and examined the influence of prostaglandins (PGs) on the process of restoration. Different degrees of mucosal damage were produced using ethanol and by varying the concentration (5-100%) and the exposure period (1-60 min). Exposure of the stomach for 10 min to ethanol induced hemorrhagic lesions and a reduction in the transmucosal potential difference (PD); its severity and its magnitude were increased in a concentration-related manner. After removal of ethanol, the reduced PD recovered quickly in the case of 5-25% ethanol, but it normalized slowly or did not show any recovery in the case of 50 or 100% ethanol, respectively. Histologically, ethanol at 5-25% produced various degrees of damage in the superficial epithelial cells, while the damage was deeper into the mucosa beyond the basal lamina after exposure to ethanol at 50% or greater. Similar phenomena were observed after exposure to 50% ethanol for various periods; the rapidity of PD recovery and mucosal restoration was faster when the exposure period was less than 2 min, and these parameters became slower as it was increased. Moreover, the PD recovery was significantly expedited or delayed, respectively, by 16,16-dimethyl PGE2 (30 micrograms/kg) or indomethacin (5 mg/kg), and the former counteracted the inhibitory effect of indomethacin. These results suggest that the process of mucosal regeneration may largely depend on the severity of damage initially formed, and probably involves factors sensitive to endogenous PGs.

Administration, Cutaneous↗
PubMed1987

Myelopathy hand. New clinical signs of cervical cord damage.

A characteristic dysfunction of the hand has been observed in various cervical spinal disorders when there is involvement of the spinal cord. There is loss of power of adduction and extension of the ulnar two or three fingers and an inability to grip and release rapidly with these fingers. These changes have been termed "myelopathy hand" and appear to be due to pyramidal tract involvement. The characteristic nature of the signs permit the distinction between myelopathy and changes due to nerve root or peripheral nerve disorder. The clinical significance of these signs has been assessed against other tests and their value in management is discussed.

Fingers↗
PubMed1987

Thoracic myelopathy secondary to ossification of the spinal ligament.

The authors describe their experience with 26 cases of thoracic myelopathy secondary to hypertrophic ossification of the spinal ligament (posterior longitudinal ligament and/or ligamentum flavum). The clinical manifestations of this condition and results of its surgical treatment are described. The commonest symptoms were numbness or tingling in the legs and feet and gait disturbance. Most of the patients with involvement of the upper thoracic spine showed typical features of thoracic myelopathy: that is, sensory and motor deficits in both the trunk and lower extremities, sphincter disturbance, and exaggerated tendon reflexes. Several patients with involvement of the thoracolumbar junction presented with atypical symptoms of thoracic myelopathy and were sometimes misdiagnosed and treated inappropriately. Surgical treatment, particularly laminectomy, was not always successful. Inconsistencies in the surgical outcome were caused by either operative complications or reversal of the initial improvement during the follow-up period. The results of anterior surgery for the condition were more favorable; however, use of this procedure was rarely indicated.

Adult↗
PubMed1987

Cervical radiculopathy or myelopathy secondary to athetoid cerebral palsy.

Radiculopathy or myelopathy often occurs during adult life in patients who have athetosis. Herniation of an intervertebral disc, spondylosis, malalignment or instability of the cervical spine, or a combination of these lesions, can develop because of the athetoid hyperactivity. We reviewed the cases of ten patients who had cervical radiculopathy or myelopathy, or both, secondary to athetosis and who were surgically treated between the ages of thirty and fifty-eight years. The surgery consisted of discectomy, removal of osteophytes, and anterior interbody fusion. When several segments were involved, an extensive subtotal resection of the vertebrae and discs, followed by strut bone-grafting, was done.

Adult↗