[Show abstract][Hide abstract] ABSTRACT: Biofilms play a pivotal role in medical device-related infections. However, epidemiological analysis of biofilm formation and genotyping among clinical methicillin-resistant Staphylococcus aureus (MRSA) isolates from patients with orthopaedic infections has rarely been reported. A total of 168 MRSA strains were examined: 23 strains from patients with device-related infection (the device group); 55 from patients with device-non-related infection (the nondevice group); and 90 from asymptomatic nasal carriers (the colonization group). Pulsed-field gel electrophoresis analysis and five genotyping methods including agr typing were performed. Biofilm formation was quantified using a microtitre plate assay. The device group had a significantly higher incidence of agr-2 than the colonization group (78.3% vs. 34.4%, P=0.001). The biofilm index of the agr-2 (0.523 ± 0.572) strains was significantly higher than those of agr-1 (0.260 ± 0.418, P<0.0001) and agr-3 (0.379 ± 0.557, P=0.045). The prevalence of strong biofilm formers in the device group (43.5%) was significantly higher than that in the nondevice group (12.7%, P=0.003) and the colonization group (20.0%, P=0.020). agr-2 MRSA strains may be more likely to cause orthopaedic device infection because of their strong biofilm formation ability.
Full-text · Article · May 2011 · FEMS Immunology & Medical Microbiology
[Show abstract][Hide abstract] ABSTRACT: A prospective study.
To assess the outcome of patients with a single thoracolumbar burst fracture treated with circumferential short-segment fusion consisting of posterior reduction, short-segment fusion, and delayed staged mini-open anterior short-segment fusion.
The surgical treatment of thoracolumbar burst fractures remains controversial. In attempting to combine the advantages of posterior procedures, including initial correction of kyphosis and early decompression, and those of anterior procedures, including direct decompression and restoration of anterior column support, a combined posterior and delayed staged anterior procedure seems to be a reasonable choice. However, conventional combined procedures are invasive.
We prospectively selected 28 consecutive patients with single thoracolumbar burst fracture for circumferential short-segment fusion consisting of posterior reduction, short-segment fusion, and delayed staged mini-open anterior short-segment fusion. The pedicle screw systems were removed after confirmation of posterior bony fusion to preserve as many motion segments as possible in those patients who could be treated with circumferential monosegmental fusion. Radiographic and clinical assessment of 28 patients who received this treatment was carried out.
The mean loss of correction of kyphosis between the time of the combined procedure and final follow-up was 3.7 degrees (range, 0 to 10.2 degrees). Bony fusion was eventually achieved in all patients. There were 15 cases with monosegmental and 13 cases with bisegmental circumferential fusion. All 10 patients with initial neurological deficit improved by at least 1 Frankel grade: 3 improved by 1 grade, 5 improved by 2 grades, and 2 improved by 3 grades. In total, 27 patients, who were P1 or P2 on the Denis pain scale, were considered to have obtained clinically satisfactory results.
This combined procedure is less invasive than the conventional combined one, and finally achieves shorter stabilization, resulting in preservation of motion segments. It thus seems to be a reasonable treatment option for thoracolumbar burst fractures.
No preview · Article · Mar 2011 · Journal of spinal disorders & techniques
[Show abstract][Hide abstract] ABSTRACT: To reveal the factors that determine the natural course of subluxation of occipital-cervical lesions in rheumatoid arthritis (RA). The atlanto-axial region is one of the most common locations for lesions in RA. Some cases progress from reducible atlanto-axial subluxation (AAS) to irreducible vertical migration, while others continue to exhibit reducible AAS. No study has revealed the factors that determine the natural course of subluxation. We focus on the odontoid as a key structure of the progression of occipito-cervical lesions and investigated this region in patients with RA using reconstructive computed tomography (CT) images, and analyzed factors in association with CT findings.
Fifty-eight patients with RA and 40 age-matched controls, all women, were studied. Associated factors, including C-reactive protein, erythrocyte sedimentation rate, steroid usage, and the severity of local osteoporosis, were analyzed as measurements in association with odontoid destruction.
The destruction of odontoid and atlanto-odontoid joint were common in patients with RA. The more destruction observed in the odontoid process, the greater is the degree of progression of vertical migration. Local osteoporosis is a significant factor in odontoid destruction, based on a cortico-cancellous index of 42% in cases of grade III odontoid destruction.
The odontoid process is a key structure in the progression of occipito-cervical lesions in patients with RA.
No preview · Article · Mar 2011 · The Journal of Rheumatology
[Show abstract][Hide abstract] ABSTRACT: Osteoid osteoma of the spine is a relatively rare bone-forming tumor. Pain that is worse at night and relieved by aspirin and muscle contracture are the most characteristic symptoms of spinal osteoid osteoma. Although radicular pain occasionally occurs in spinal osteoid osteoma, spinal cord and nerve root compression is absent in most cases. Although radicular pain appears to be associated with tumorous inflammation, there have been no presentations of histological findings of inflammation around the nerve root. We present here two rare cases of spinal osteoid osteoma causing radiculopathy and the first histological evidence of tumorous inflammation as a cause of radiculopathy in osteoid osteoma near the intervertebral foramen.
Preview · Article · Jan 2011 · Diagnostic Pathology
[Show abstract][Hide abstract] ABSTRACT: We report a case of a 69-year-old man with dropped head syndrome associated with isolated neck extensor myopathy (INEM). Over a period of 2 years, he exhibited progressive inability to lift his chin off his chest, resulting in the dropped head position that impaired his activities of daily living. He had a disturbed gait with severe imbalance of spinal alignment. Computed tomography revealed osseous contracture of cervical vertebral bodies in flexed position. Anterior combined posterior reconstruction surgery yielded a successful outcome in his activities of daily living, including his walking balance of spinal alignment. Pathologic study confirmed myogenic atrophy in the cervical extensor muscles. We suggest that consideration for surgical management should be given to dropped head syndrome especially due to INEM.
Preview · Article · Jan 2011 · Diagnostic Pathology
[Show abstract][Hide abstract] ABSTRACT: Tethered cord syndrome with spinal lipoma is the most common form of occult spinal dysraphism. For the symptomatic patients, surgical treatment is recommended; however, there are many patients who have not been encouraged to seek medical attention until adulthood, since their symptoms are not severe enough to interfere with their daily activities. We performed pedicle subtraction osteotomy (PSO) to achieve indirect untethering and neural decompression in two senior patients with tethered cord syndrome, who showed deteriorating neurological condition due to coexisting lumbar canal stenosis. Here we report two patients (aged 56 and 60 years) who underwent PSO of L3 or L4. The pain disappeared and the bladder dysfunction recovered significantly after surgery. Complete bone union and untethering were achieved in both patients. PSO is an alternative surgical technique for senior patients with tethered cord syndrome caused by lumbosacral spinal lipoma, when the syndrome occurs along with lumbar canal stenosis.
No preview · Article · Nov 2010 · The International journal of neuroscience
[Show abstract][Hide abstract] ABSTRACT: Spinal subependymomas, which have a relatively benign nature, are very rare tumors. It is difficult to distinguish spinal subependymomas from other intramedullary spinal tumors based on neuroradiological findings. A case of cervical intramedullary subependymoma in a 63-year-old female is reported. The diffused enlargement of the spinal cord at C2 level involved the lesion with isointensity on a T1-weighted MRI and relatively high intensity on a T2-weighted MRI. Enhancement in the small part of the tumor was observed on a T1-weighted MRI with gadolinium administration. The tumor occupied the left side of the spinal cord, and was totally removed through a laminoplasty of C2. Immunohistochemistry was useful for pathological diagnosis. The clinical feature of this patient is described with the review of literatures.
No preview · Article · Oct 2010 · The International journal of neuroscience
[Show abstract][Hide abstract] ABSTRACT: Although the diagnosis of chondrosarcoma, especially the distinction between enchondroma and low-grade chondrosarcoma or low-grade chondrosarcoma and high-grade chondrosarcoma, is pathologically difficult, differential diagnosis is very important because the treatment strategies for these diseases are completely different. The grading system is crucial in predicting biologic behavior and prognosis, however, exact pathological grading is difficult using only routine examinations because the criteria of the grading system are not necessarily definitive. Growth arrest and DNA damage-inducible protein 45β (GADD45β) is an essential molecule for chondrocytes during terminal differentiation. In the present study, we investigated the immunohistochemical expression of GADD45β in enchondroma, and chondrosarcoma of histological grades I, II, and III, to clarify the diagnostic significance of GADD45β in pathological grading of chondrosarcoma.
Twenty samples (enchondroma = 6, chondrosarcoma grade I = 7, grade II = 6, grade III = 1) were used for immunohistochemical analysis to investigate the expression of GADD45β. Quantitative analysis was performed to compare the number of GADD45β positive cells and pathological grading.
Over 70% of the cells in enchondromas expressed GADD45β. On the other hand, the expression of GADD45β decreased significantly according to the histological grade of chondrosarcoma (grade I: 45%; grade II: 13.8%; and grade III: 3.8%).
The association of GADD45β expression and pathological grading of chondrosarcoma in the present study suggests that the immunohistochemical study of GADD45β may be a specific diagnostic parameter for chondrosarcoma cell differentiation.
Full-text · Article · Oct 2010 · Diagnostic Pathology
[Show abstract][Hide abstract] ABSTRACT: Intradural neurenteric cysts are rare congenital lesions and arise from incomplete separation of the developing notochord and foregut in the embryo. Neurenteric cysts are often seen in conjunction with other forms of occult spinal dysraphism. The cases of a 48-year-old male with pain in the right shoulder and numbness in both hands and a 7-year-old girl with subacute muscle weakness of the lower extremities are presented. Both patients underwent surgery. One lesion was completely excised, while the other could be only partially removed because of negative monitoring potential during the operation. Histological examination, showing pseudostratified ciliated columnar epithelium, confirmed the diagnosis of neurenteric cyst. The symptoms in both patients nearly disappeared after surgery. Recurrence of cyst was observed in the girl, though without neurological symptoms. In conclusion, two cases of intradural extramedullary cysts are reported. Clinical presentations, intraoperative findings, and histological features are discussed with a review of the literature.
No preview · Article · Sep 2010 · The International journal of neuroscience
[Show abstract][Hide abstract] ABSTRACT: The N-myc downstream regulated gene 1 (NDRG1)/Cap43 is closely associated with cell differentiation, and its expression is induced by hypoxia and increasing intracellular calcium levels. Whether the NDRG1/Cap43 expression in cancer cells is a predictive marker of good or poor prognosis in patients, depends upon tumor types and differentiation status. In this study, we examined whether the NDRG1/Cap43 expression was involved in the differentiation of osteosarcoma cells, using three osteosarcoma cell lines, MG63, U2OS and SaOS2. The NDRG1/Cap43 expression in MG63 and U2OS was significantly enhanced by vitamin D3, which also induced the production of osteocalcin, a differentiation marker of osteoblasts. The knockdown of NDRG1/Cap43 using small interfering RNA also suppressed the production of osteocalcin and enhanced cell proliferation, accompanied by the suppression of p21 expression. Furthermore, the acquired invasiveness of osteosarcoma cells during the invasion in Matrigel resulted in the decreased expression of NDRG1/Cap43. On the basis of these results, our proposed role for NDRG1/Cap43 would be in the capacity of differentiation and invasion in osteosarcoma cells.
No preview · Article · Sep 2010 · Oncology Reports
[Show abstract][Hide abstract] ABSTRACT: To examine the radiological features of vertebral artery (VA) displacement/occlusion associated with rheumatoid arthritis (RA) spine using magnetic resonance angiography.
Forty-seven RA patients with upper cervical lesions were evaluated for patency or abnormality of the VA by extracranial magnetic resonance angiography, with comparison of findings with those of 46 healthy volunteers.
VA occlusion occurred in 4 patients (8.5%) and VA stenosis in 9 patients (19.1%). Anomaly of the VA was also observed in 3 patients (6.4%). No occlusion or anomaly was found in healthy volunteers, but 1 case of stenosis was found. Severity of vertical subluxation was correlated with the presence of VA abnormality in RA patients.
The incidence of VA abnormality was 34% in RA patients and 2% in healthy volunteers. Magnetic resonance angiography is useful for screening for abnormality of the entire VA.
[Show abstract][Hide abstract] ABSTRACT: The immunohistological features and surgical treatment of an intramedullary ependymal cyst in the conus medullaris is presented. An intramedullary ependymal cyst is a rare lesion of dysembryoplastic origin. There have been only seven patients reported with pathologically proven ependymal cysts in the conus medullaris. A 64-year-old woman reported pain and numbness in both thighs and feet. Neither sensory nor motor impairment was present in the lower extremities. MRI revealed a cyst on the right side of the conus medullaris, compressing the spinal cord upward. Clinical signs and symptoms disappeared following surgical resection of the cyst. Histological examination showed that this cyst was lined with a single layer of tall columnar or low cuboidal cells on fibrous connective tissue. The basement membrane was absent in the cyst wall. Reactivity to CAM5.2 and AE1/AE3 anti-keratin antibodies suggested that the cyst was of neuroepithelial origin. No recurrence has been noted 3 years after surgery.
No preview · Article · Feb 2010 · Journal of Clinical Neuroscience