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Y Kurosa

Publications and source records attributed to Y Kurosa.

8 recordsLinked to original sources
PubMed2001

Long-term results of the anterior floating method for cervical myelopathy caused by ossification of the posterior longitudinal ligament.

STUDY DESIGN: Results of the anterior floating method used to decompress ossification of the posterior longitudinal ligament were studied for an average postoperative interval of 13 years. OBJECTIVE: To investigate the long-term results of the anterior floating method used to manage ossification of the posterior longitudinal ligament. SUMMARY OF BACKGROUND DATA: The anterior floating method is a technique that differs from the extirpation method used to manage ossification of the posterior longitudinal ligament. Reports of the long-term results from anterior decompression used to manage cervical ossification of the posterior longitudinal ligament are rare. METHODS: The anterior floating method was used to decompress cervical ossification of the posterior longitudinal ligament in 63 patients. These patients were followed for more than 10 years with neurologic evaluations using a scoring system proposed by the Japanese Orthopedic Association (JOA score). RESULTS: The recovery rate was 66.5% at 10 years and 59.3% at 13 years, the time of the final survey. Operative outcomes most closely reflected the preoperative duration and severity of myelopathy (JOA score) and the preoperative cross-sectional area of the spinal cord. There was no correlation with the canal narrowing ratio or the thickness of ossification of the posterior longitudinal ligament. Delayed deterioration was attributed to an original inadequate decompression and progression of ossification of the posterior longitudinal ligament outside the original operative field. There was no evidence of significant recurrent ossification of the posterior longitudinal ligament within the margins of prior decompression. CONCLUSIONS: The anterior floating method appears to yield adequate long-term outcomes when used to manage ossification of the posterior longitudinal ligament.

Adult↗
PubMed2000

Multiple sclerosis with very late onset: a report of a case with onset at age 82 years and review of the literature.

This is a report of a patient with late-onset multiple sclerosis at age 82 years. The lesion involved was located on the spinal cord. Multiple sclerosis mainly affects young adults, making late onset of multiple sclerosis a rarity, particularly for cases after age 80 years. Common characteristics of late-onset multiple sclerosis reported in other publications are predominant involvement of the spinal cord and a progressively worsening course with a serious prognosis. In this case, magnetic resonance imaging revealed a large area of high signal intensity in the cervical and upper thoracic spinal cord on T2-weighted images. An increased immunoglobulin G level in cerebrospinal fluid also played a diagnostic role in ruling out cervical spondylotic myelopathy. Spontaneous improvement occurred 2 months after the onset. Unlike other patient described in the literature, the clinical course of this man was not as bleak.

Age of Onset↗
PubMed1999

Anterior floating method for cervical myelopathy caused by ossification of the posterior longitudinal ligament.

Ossification of the posterior longitudinal ligament lessens the sagittal diameter of the cervical canal and compresses the spinal cord anteriorly, and may produce severe disabling myelopathy. The anterior floating method is one of the anterior decompression and reconstructions used in the treatment of cervical myelopathy caused by ossification of the posterior longitudinal ligament. This procedure consists of subtotal resection of vertebral bodies and discs, with slight thinning and release of the ossified ligament using air instrumentation. This is followed by reconstruction of the cervical spine using autogenous strut bone graft accompanied by postoperative application of a halo vest. This method is indicated for patients who present with moderate or severe myelopathies, and especially in those where the canal narrowing ratio exceeds 60%. This radical procedure causes decompression of the spinal cord and restores its function by enlarging the neural canal with anterior migration of the ossified ligament. The procedure minimizes the extent of surgical invasions and avoids damage to the neural tissue, because it does not require the removal of the ossification of the posterior longitudinal ligament. It also stops postoperative regrowth of the ossification. The operative results with long term followup indicate a 71% average recovery rate based on the criteria established by the Japan Orthopedic Association.

Adult↗
PubMed1997

Lumbar nerve root compression caused by lumbar intraspinal gas. Report of three cases.

STUDY DESIGN: Three cases of lumbar nerve root compression associated with intradiscal gas formation and its migration are reported. OBJECTIVES: To establish the pathogenic mechanism by which gas is formed in the spinal canal. SUMMARY OF BACKGROUND DATA: Few such cases have been reported of patients with clinical symptoms of lumbar radiculopathy resulting from gas in the spinal canal. METHODS: Surgery with needle aspiration of the gas was performed in all cases. RESULTS: The presence of the gas was detected in the extradural space in one patient and within the nerve sheath in two patients. After surgery, all patients recovered well, and there were no obvious remnant neurologic abnormalities. One year later, all patients were completely free of symptoms. CONCLUSIONS: Surgery with needle aspiration of the gas resulted in clinical improvement in all cases, confirming that intraspinal gas is an important cause of lumbar radiculopathy. The composition of the gas in one patient was analyzed by gas chromatography, which revealed an overwhelming preponderance of nitrogen. A relationship between a gas-containing pseudocyst in the spinal canal and a degenerated intervertebral disc was identified, a key finding for understanding the precise nature of this disorder. Intradiscal gas formation and its outward migration as a sequel of intervertebral disc degeneration also has been addressed in this report.

Aged↗
PubMed1996

Selecting a surgical method for thoracic myelopathy caused by ossification of the posterior longitudinal ligament.

STUDY DESIGN: The authors classified typical distributional patterns of ossification of the posterior longitudinal ligament of the thoracic spine in 1) central part of S-curve, 2) just above apical vertebra, and 3) combined with ossification of ligamentum flavum below apical vertebra. The results of the surgical methods selected according to the authors' classification were compared with those of previous reports. OBJECTIVES: To establish the criteria for selecting an appropriate surgical method for ossification of the posterior longitudinal ligament of the thoracic spine. SUMMARY OF BACKGROUND DATA: Poor surgical results for ossification of the posterior longitudinal ligament of "middle or lower thoracic spine" have been reported, but the unsuccessful location and curve has not been strictly defined. METHODS: The authors studied postsurgical results in 26 cases of thoracic myelopathy caused by ossification of the posterior longitudinal ligament. They also investigated radiographs of 111 cases, including 85 patients under observation, and examined the relationships between thoracic spine alignment and ossification of the posterior longitudinal ligament distribution. RESULTS: Twenty-three patients treated with methods conforming to the authors' criteria achieved satisfactory recovery in walking ability except for one patient. The results of the other three patients who underwent surgery with nonconforming methods were uneven. CONCLUSION: Posterior decompression, as well as anterior decompression, is effective in the first pattern in the cervicothoracic region. In case of the second pattern, the responsible ossification of the posterior longitudinal ligament always lies one or two levels above the apical vertebra and should be removed by anterior approach, regardless of the extent of kyphosis. Transthoracic anterior decompression surgery is considered the best method for most patients under the second and third patterns.

Adult↗
PubMed1989

Clinical study of dissociated motor weakness following anterior cervical decompression surgery.

C5 segment motor loss (deltoid muscle) after a cervical spinal operation, either anterior decompression or posterior decompression, has rarely been reported. However, most such cases are diagnosed immediately after surgery, and they appear to be due to inadequate surgical technique or insufficient decompression. Recently, the authors have experienced three cases in which weakness of the deltoid muscle started several days following anterior cervical decompression surgery. On the basis of postoperative plain films, myelography, and computed tomography (CT) myelography, the cause of the motor weakness was considered to be C5 root disturbance due to postoperative malalignment of the cervical spine, which gradually increased. The malalignment of the cervical spine seemed to be due to weakness of iliac bone grafts, inadequate design of the bone graft and recipient site, and insufficient postoperative fixation. To prevent this malalignment, eg, lateral inclination of the bone graft to axial rotation deformity, adequate bone graft design is required. The authors have been performing internal fixation using sapphire screws on cases in which fusion extending over four vertebral bodies is required.

Adult↗
PubMed1988

Electrophysiologic diagnosis of cervical OPLL myelopathy using evoked spinal cord potentials.

The purpose of this study is to establish the correct diagnosis of the location and extent of intraspinal cord lesions in cases of continuous or mixed-type ossification of the posterior longitudinal ligament and to estimate the postoperative prognosis using evoked spinal cord potentials (ESCP). Twenty-six patients, who underwent surgery from 1985 to 1987 and who have been followed for more than 6 months, were examined using a conductive ESCP, which demonstrates lower extremity, bowel, and bladder function, and a segmental ESCP and dermatome segmental ESCP, which demonstrate upper extremity function. A five-pole recording electrode was placed in the cervical epidural space. The stimulation sites were the thoracic epidural space for conductive ESCP, the median nerve at the elbow for the segmental ESCP, and the finger surface for the dermatome segmental ESCP. In cases in which the ESCP disappeared at the middle of the narrow cervical spinal canal, another stimulating electrode was placed in the cisterna magna, and a descending conductive ESCP was recorded to monitor the upper border of the spinal lesion. New findings, which could not be observed by roentgenograms, myelography, and CT scan, were detectable using this technique.

Aged↗