Radiological Analysis of Cerebrospinal Fluid Dynamics at the Craniovertebral Junction Using Time-Spatial Labeling Inversion Pulse Magnetic Resonance Imaging in Patients with Cervical Spinal Canal Stenosis.

OBJECTIVE: Spondylotic changes in the cervical spine cause degeneration, leading to cervical spinal canal stenosis. This stenotic change can affect cerebrospinal fluid (CSF) dynamics by compressing the dural sac and reducing space in the subarachnoid space. We examined CSF dynamics at the craniovertebral junction (CVJ) using time-spatial labeling inversion pulse magnetic resonance imaging (Time-SLIP MRI) in patients with cervical spinal canal stenosis. METHODS: The maximum longitudinal movement of the CSF at the CVJ was measured as length of motion (LOM) in the Time-SLIP MRI of 56 patients. The sum of ventral and dorsal LOM was defined as the total LOM. Patients were classified into 3 groups depending on their spinal sagittal magnetic resonance imaging findings: control (n = 27, Kang classification grades 0 and 1), stenosis (n = 14, Kang classification grade 2), and severe stenosis (n = 15, Kang classification grade 3). RESULTS: Time-SLIP MRI revealed pulsatile movement of the CSF at the CVJ. The mean total, ventral, and dorsal LOM was 14.2 ± 9, 8.1 ± 5.7, and 3.8 ± 2.9 mm, respectively. The ventral LOM was significantly larger than the dorsal LOM. The total LOM was significantly smaller in the severe stenosis group (6.1 ± 3.4 mm) than in the control (16.0 ± 8.4 mm) or stenosis (11 ± 5.4 mm) groups (P < 0.001, Kruskal-Wallis H-test). In 5 patients, postoperative total LOM was improved after adequate decompression surgery. CONCLUSIONS: This study demonstrates that CSF dynamics at the CVJ are influenced by cervical spinal canal stenosis. Time-SLIP MRI is useful for evaluating CSF dynamics at the CVJ in patients with spinal canal stenosis.

Surgical results of the resection of spinal meningioma with the inner layer of dura more than 10 years after surgery.

Most spinal meningiomas arise from the thoracic dura in middle-aged and elderly women. Simpson grade 1 resection is recommended to avoid recurrence. For ventral and ventrolateral tumors, reconstruction after total dural resection is difficult, and spinal fluid leakage is likely. To overcome this concern, Saito et al. developed the technique of resecting the tumor with the inner dural layer, preserving the outer dural layer. Although meningioma rarely recurs, the recurrence period is approximately 8 years postoperatively. No studies have evaluated long-term (> 10-year) outcomes of the Saito method. Here, we report 10 cases of the Saito method with > 10-year follow-up and compare outcomes with those of other standard approaches. Twenty-nine pathology-confirmed meningioma patients underwent surgery in our department, ten with the Saito method. We investigated resection method (dura mater treatment), pathological type, and recurrence and compared pre- and postoperative clinical findings. The median follow-up was 132 months. Recurrence occurred after Simpson grades 3 and 4 resection. Simpson grades 1, 2, and the Saito method resulted in no recurrence. Neurological symptoms improved in all patients at final follow-up. This is the first report of long-term outcomes of the Saito method. The method achieved good neurological improvement with no recurrence in > 10-year follow-up.

A Case of C5 Vertebral Chordoma in a 73-Year-Old Patient with More Than 8 Years of Follow-Up after Total Piecemeal Spondylectomy.

Chordoma arising from the cervical spine is rare and the traditional long-term prognosis is typically poor. Total en bloc spondylectomy with a wide margin is generally accepted to be the most appropriate management for thoracic and lumbar malignant tumors. However, this method is still challenging for the cervical spine because of the proximity of the tumor to the vertebral arteries and neural elements. Here, we report a 73-year-old man with a C5 vertebral chordoma treated with total piecemeal spondylectomy. Histological examination revealed pathognomonic physaliphorous cells with mucus-filled cytoplasm in the tumor, and the ratio of Ki-67-positive cells within the tumor was high (19.0%), showing active proliferation rate. Local recurrences were found at 9 months, 4 years and 2 months, and 6 years after the initial surgery. All the recurrences were encapsulated and isolated and treated with an additional en bloc resection successfully at each stage. Eight years after the initial total piecemeal spondylectomy, the patient maintained his intact neurological status without local recurrence or metastasis. The prognosis of cervical chordoma depends on the patient's age, surgical procedures, and histological features. In this report, we present that piecemeal spondylectomy is an alternative management for aged patients with cervical chordoma, even for those with high MIB-1 index.

CCAAT/enhancer binding protein ß (C/EBPß) regulates the transcription of growth arrest and DNA damage-inducible protein 45 ß (GADD45ß) in articular chondrocytes.

Osteoarthritis (OA) is a whole joint disease characterized by cartilage degradation, which causes pain and disability in older adults. Our previous work showed that growth arrest and DNA damage-inducible protein 45 ß (GADD45ß) is upregulated in chondrocyte clusters in OA cartilage, especially in the early stage of this disease. CCAAT/enhancer binding protein ß (C/EBPß) is expressed in the hypertrophic growth plate chondrocytes and functions in synergy with GADD45ß. Here, the presence and localization of these proteins was assessed by immunohistochemistry using articular cartilage from OA patients, revealing colocalization of C/EBPß and GADD45ß in OA chondrocytes. GADD45ß promoter analysis was performed to determine whether C/EBPß directly regulates GADD45ß transcription. Furthermore, we analyzed the effect of C/EBPß on Gadd45ß gene regulation in articular chondrocytes in vivo and in vitro. Immunohistochemical analysis of C/ebpß-haploinsufficient mice (C/ebpß(+/-)) cartilage showed that C/ebpß haploinsufficiency led to reduced Gadd45ß gene expression in these cells. In vitro, we evaluated the effects of conditional C/EBPß overexpression driven by the cartilage oligomeric matrix protein (Comp) promoter in mComp-tTA;pTRE-Tight-BI-DsRed-mC/ebpß transgenic mice. C/EBPß overexpression significantly stimulated Gadd45ß gene expression in articular chondrocytes. Taken together, our data demonstrate that C/EBPß plays a central role in controlling Gadd45ß gene expression in these cells.

Retro-odontoid mass without atlantoaxial instability causing cervical myelopathy: a case report of transdural surgical resection.

INTRODUCTION: Retro-odontoid mass rarely occur in patients with noninflammatory retro-odontoid lesions without atlantoaxial instability. We describe a rare case of retro-odontoid mass without atlantoaxial instability operated on by a transdural approach. CASE PRESENTATION: The patient was an 83-year-old man who presented with a retro-odontoid mass causing symptomatic cervical myelopathy. Preoperative magnetic resonance imaging (MRI) revealed that the mass was severely compressing the spinal cord. We operated on it via a C1 laminectomy and performed tumor resection by a transdural approach. Pathological findings from the operative specimen confirmed the diagnosis; histopathological examination revealed that the mass contained fibrinoid material, and collagenous tissue with myxoid changes, but no granulation or a granulomatous lesion. Postoperative MRI confirmed spinal cord decompression. The patient's symptoms were alleviated, and he has not had a recurrence or cervical instability in the 7 years since his surgery. DISCUSSION: We successfully used a transdural approach in the present case and have observed no recurrence for 7 years postoperatively. C1 laminectomy is reportedly beneficial, especially for elderly patients, given the risk of other surgical options using an anterior transoral approach or posterior fusion. However, most tumors do not attenuate after C1 laminectomy alone; hence, we think that tumor resection by the transdural approach is one effective method to perform enucleation of the tumor after C1 laminectomy.

Epithelial sodium channel enhanced osteogenesis via cGMP/PKGII/ENaC signaling in rat osteoblast.

The amiloride-sensitive epithelial sodium channel (ENaC) is a major contributor to intracellular sodium homeostasis. In addition to epithelial cells, osteoblasts (Obs) express functional ENaCs. Moreover, a correlation between bone Na content and bone disease has been reported, suggesting that ENaC-mediated Na(+) regulation may influence osteogenesis. Obs were isolated and cultured by enzyme digestion. Cell proliferation and differentiation were evaluated by WST-8 assay kit and AKP assay kit respectively. PKGII expression was silenced by siRNA. The mRNA expression was investigated by semi-quantitative PCR and the protein expression was determined by Western-blot. The cell-permeable cGMP analog 8-(4-chlorophenylthio)-cGMP (8-pCPT-cGMP) increased α-ENaC channel expression in primary rat Obs as indicated by RT-PCR. In addition, 8-pCPT-cGMP stimulation enhanced expression of the mRNA encoding cGMP-dependent protein kinases II (PKGII). The cGMP analog also promoted osteoblast proliferation, differentiation and induced the expression of several osteogenic genes, including core binding factor al, osteocalcin, alkaline phosphatase, collagen type I, and osteopontin. Furthermore, the expression of α-ENaC, the main functional subunit of ENaC, was reduced when a small interfering RNA specific for PKGII was introduced into Obs. Treatment with 8-pCPT-cGMP in cells transfected with the siRNA for PKGII partially reversed downregulated α-ENaC mRNA expression. Our results suggest that 8-pCPT-cGMP stimulates proliferation, differentiation, and osteogenic gene expression in Obs through cGMP/PKGII-dependent regulation of ENaC channel expression. The cGMP/PKGII signaling pathway is a potential target for pharmaceutical interventions to treat metabolic bone diseases.

Paget disease of bone in Japanese patients: a report of three cases.

Paget disease of bone (PDB) is a bone metabolic disorder causing pain, fractures, and deformity. Its incidence is estimated to be 1 to 2% in Caucasians older than 55 years, but in Asian populations the incidence is rare. We report on 2 female and one male Japanese patients aged 46 to 73 years with PDB. One patient had monostotic disease with pain around the shoulder and the other 2 were asymptomatic. All patients had elevated alkaline phosphatase (ALP) levels (range, 629-957 U/L). Two patients responded to oral bisphosphonate treatment and achieved normalised ALP levels and pain relief. One patient with polyostotic disease did not show any change in ALP levels. The diagnosis of the disease and the indications for bisphosphonate treatment are discussed.

A newly developed robot suit hybrid assistive limb facilitated walking rehabilitation after spinal surgery for thoracic ossification of the posterior longitudinal ligament: a case report.

Most patients with thoracic ossification of the posterior longitudinal ligament (OPLL) exhibit delayed recovery of gait dysfunction after spinal injury. The hybrid assistive limb (HAL) is a new robot suit controlling knee and hip joint motion by detecting very weak bioelectric signals on the surface of the skin. This study is to report the feasibility and benefits of patient-assistive HAL walking rehabilitation for facilitating locomotor function after spinal surgery. The patient was a 60-year-old woman with thoracic OPLL, and her motor and sensory paralyses did not improve after spinal surgery, indicating severe impairment in the paretic legs. The subject underwent 6 HAL sessions per week for 8 weeks, consisting of a standing and sitting exercise and walking on the ground with HAL. Clinical outcomes were evaluated before and after HAL training and 1 year after surgery. The subject improved considerably as a result of HAL training. Subsequently, her walking ability recovered rapidly, and she was able to walk unaided six months after surgery. This case study suggests that HAL training is a feasible and effective option to facilitating locomotor function and the early HAL training with physiotherapy may enhance motor recovery of patients with residual paralysis after surgery.

Combined posterior and delayed staged mini-open anterior short-segment fusion for thoracolumbar burst fractures.

STUDY DESIGN: A prospective study. OBJECTIVES: 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. SUMMARY OF BACKGROUND DATA: 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. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Pharmacological inhibition of the Hedgehog pathway prevents human rhabdomyosarcoma cell growth.

The Hedgehog pathway functions as an organizer in embryonic development. Recent studies have shown that mutation of the PTCH1 gene involved in the Hedgehog pathway affects rhabdomyosarcoma development. However, the expression of Hedgehog pathway molecules in human rhabdomyosarcoma cells has not been well clarified. In addition, the effect of pharmacological inhibition of the Hedgehog pathway is not known. We investigated the expression of the genes involved in the Hedgehog pathway using human rhabdomyosarcoma cell lines and biopsy specimens. Further, we evaluated the effect of pharmacological inhibition of the Hedgehog pathway using cyclopamine or GANT61 by WST assay, cell proliferation assay and cell death detection assay. Real-time PCR revealed that human rhabdomyosarcoma cell lines and biopsy specimens overexpressed the following genes: Sonic hedgehog, Indian hedgehog, Desert hedgehog, PTCH1, SMO, GLI1, GLI2 and ULK3. Immunohistochemistry revealed that rhabdomyosarcoma cell lines and biopsy specimens expressed SMO and GLI2. Inhibition of SMO by cyclopamine slowed the growth of human rhabdomyosarcoma cell lines. Similarly, inhibition of GLI by GANT61 slowed the growth of human rhabdomyosarcoma cell lines. Inhibition of cell proliferation and apoptotic cell death together prevented the growth of rhabdomyosarcoma cells by cyclopamine and GANT61 treatment. Our findings suggest that pharmacological inhibition of the Hedgehog pathway may be a useful approach for treating rhabdomyosarcoma patients.

Quantitative analysis of biofilm formation of methicillin-resistant Staphylococcus aureus (MRSA) strains from patients with orthopaedic device-related infections.

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.

Role of GLI2 in the growth of human osteosarcoma.

The Hedgehog pathway functions as an organizer in embryonic development. Aberrant activation of the Hedgehog pathway has been reported in various types of malignant tumours. The GLI2 transcription factor is a key mediator of Hedgehog pathway but its contribution to neoplasia is poorly understood. To establish the role of GLI2 in osteosarcoma, we examined its expression by real-time PCR using biopsy tissues. To examine the function of GLI2, we evaluated the growth of osteosarcoma cells and their cell cycle after GLI2 knockdown. To study the effect of GLI2 activation, we examined mesenchymal stem cell growth and the cell cycle after forced expression of GLI2. We found that GLI2 was aberrantly over-expressed in human osteosarcoma biopsy specimens. GLI2 knockdown by RNA interferences prevented osteosarcoma growth and anchorage-independent growth. Knockdown of GLI2 promoted the arrest of osteosarcoma cells in G(1) phase and was accompanied by reduced protein expression of the cell cycle accelerators cyclin D1, SKP2 and phosphorylated Rb. On the other hand, knockdown of GLI2 increased the expression of p21(cip1) . In addition, over-expression of GLI2 promoted mesenchymal stem cell proliferation and accelerated their cell cycle progression. Finally, evaluation of mouse xenograft models showed that GLI2 knockdown inhibited the growth of osteosarcoma in nude mice. Our findings suggest that inhibition of GLI2 may represent an effective therapeutic approach for patients with osteosarcoma.

Classification of odontoid destruction in patients with rheumatoid arthritis using reconstructed computed tomography: reference to vertical migration.

OBJECTIVE: 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. METHODS: 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. RESULTS: 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. CONCLUSION: The odontoid process is a key structure in the progression of occipito-cervical lesions in patients with RA.

Senescence of chondrocytes in aging articular cartilage: GADD45ß mediates p21 expression in association with C/EBPß in senescence-accelerated mice.

Growth arrest and DNA damage-inducible protein 45ß (GADD45ß) is expressed in normal and early osteoarthritic articular cartilage. We recently reported that GADD45ß enhances CCAAT/enhancer binding protein ß (C/EBPß) activation in vitro. This study was undertaken in order to determine whether GADD45ß is expressed with C/EBPß in aging articular cartilage. We also investigated whether the synergistic expression of GADD45ß and C/EBPß may be involved in the mechanism of chondrocyte senescence. Senescence-accelerated mice (SAMP1) were used as a model of aging. GADD45ß, C/EBPß, and p21 were analyzed by immunohistochemistry. A luciferase reporter assay using ATDC5 cells was performed in order to examine p21 as a target gene of the GADD45ß/C/EBPß cascade. GADD45ß exhibited increased expression in the aging articular cartilage of SAMP1 mice compared to that in control mice. The co-localization of GADD45ß and C/EBPß was confirmed by double immunostaining. The synergistic mechanisms of GADD45ß and C/EBPß on the gene regulation of p21, a molecule related to cellular senescence, were verified by a p21-luciferase reporter assay. Co-expression of C/EBPß and p21 was confirmed. These observations suggest that the synergism between GADD45ß and C/EBPß may play an important role in cellular senescence in the aging articular cartilage.

Suppression of osteosarcoma cell invasion by chemotherapy is mediated by urokinase plasminogen activator activity via up-regulation of EGR1.

BACKGROUND: The cellular and molecular mechanisms of tumour response following chemotherapy are largely unknown. We found that low dose anti-tumour agents up-regulate early growth response 1 (EGR1) expression. EGR1 is a member of the immediate-early gene group of transcription factors which modulate transcription of multiple genes involved in cell proliferation, differentiation, and development. It has been reported that EGR1 act as either tumour promoting factor or suppressor. We therefore examined the expression and function of EGR1 in osteosarcoma. METHODS: We investigated the expression of EGR1 in human osteosarcoma cell lines and biopsy specimens. We next examined the expression of EGR1 following anti-tumour agents treatment. To examine the function of EGR1 in osteosarcoma, we assessed the tumour growth and invasion in vitro and in vivo. RESULTS: Real-time PCR revealed that EGR1 was down-regulated both in osteosarcoma cell lines and osteosarcoma patients' biopsy specimens. In addition, EGR1 was up-regulated both in osteosarcoma patient' specimens and osteosarcoma cell lines following anti-tumour agent treatment. Although forced expression of EGR1 did not prevent osteosarcoma growth, forced expression of EGR1 prevented osteosarcoma cell invasion in vitro. In addition, forced expression of EGR1 promoted down-regulation of urokinase plasminogen activator, urokinase receptor, and urokinase plasminogen activity. Xenograft mice models showed that forced expression of EGR1 prevents osteosarcoma cell migration into blood vessels. CONCLUSIONS: These findings suggest that although chemotherapy could not prevent osteosarcoma growth in chemotherapy-resistant patients, it did prevent osteosarcoma cell invasion by down-regulation of urokinase plasminogen activity via up-regulation of EGR1 during chemotherapy periods.

Neurological complications of cervical laminoplasty for patients with ossification of the posterior longitudinal ligament-a multi-institutional retrospective study.

STUDY DESIGN: Retrospective multi-institutional study. OBJECTIVE: To investigate the incidence of neurological deficits after cervical laminoplasty for ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: According to analysis of long-term results, laminoplasty for cervical OPLL has been reported as a safe and effective alternative procedure with few complications. However, perioperative neurological complication rates of laminoplasty for cervical OPLL have not been well described. METHODS: Subjects comprised 581 patients (458 men and 123 women; mean age: 62 ± 10 years; range: 30-86 years) who had undergone laminoplasty for cervical OPLL at 27 institutions between 2005 and 2008. Continuous-type OPLL was seen in 114, segmental-type in 146, mixed-type in 265, local-type in 24, and not judged in 32 patients. Postoperative neurological complications within 2 weeks after laminoplasty were analyzed in detail. Cobb angle between C2 and C7 (C2/C7 angle), maximal thickness, and occupying rate of OPLL were investigated. Pre- and postoperative magnetic resonance imaging was performed on patients with postoperative neurological complications. RESULTS: Open-door laminoplasty was conducted in 237, double-door laminoplasty in 311, and other types of laminoplasty in 33 patients. Deterioration of lower-extremity function occurred after laminoplasty in 18 patients (3.1%). Causes of deterioration were epidural hematoma in 3, spinal cord herniation through injured dura mater in 1, incomplete laminoplasty due to vertebral artery injury while making a trough in 1, and unidentified in 13 patients. Prevalence of unsatisfactory recovery not reaching preoperative level by 6-month follow-up was 7/581 (1.2%). Mean occupying rate of OPLL for patients with deteriorated lower-extremity function was 51.2 ± 13.6% (range, 21.0%-73.3%), significantly higher than the 42.3 ± 13.0% for patients without deterioration. OPLL thickness was also higher in patients with deterioration (mean, 6.6 ± 2.2 mm) than in those without deterioration (mean, 5.7 ± 2.0 mm). No significant difference in C2/C7 lordotic angle was seen between groups. CONCLUSION: Although most neurological deterioration can be expected to recover to some extent, the frequency of short-term neurological complications was higher than the authors expected.

Dropped head syndrome due to myogenic atrophy - a case report of surgical treatment.

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.

Osteoid osteoma near the intervertebral foramen may induce radiculopathy through tumorous inflammation.

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.

Isokinetic trunk and knee muscle strengths and gait performance in walking patients with T-cell lymphotropic virus type 1-associated myelopathy/ tropical spastic paraparesis (HAM/TSP).

The aim of this study was to investigate the isokinetic trunk and knee muscle strengths, and examine the clinical relevance of dynamic muscle strengths and gait performance in walking patients with human T-cell lymphotropic virus type 1-associated myelopathy/ tropical spastic paraparesis (HAM/TSP). Thirteen patients with HAM/TSP (8 females and 5 males, aged 38-76) and 13 sex- and age-matched healthy control subjects participated in the study. We assessed gait speed, stride length, cadence; and maximal isokinetic torque of trunk and knee extensors and flexors at 30°/s, 60°/s and 90°/s using a Biodex System 3 dynamometer. Furthermore, we calculated the isokinetic trunk extensor/flexor (E/F) and hamstrings/quadriceps (H/Q) strength ratios (parameter of the muscle strength balance about the trunk and knee joint). Compared with the age-matched controls, the patients with HAM/TSP had significantly reduced gait speed, stride length and cadence (P < 0.05). Peak torque values related to body weight (PTBW) were significantly reduced, especially for the knee flexors (P < 0.05). For the knee extensors, the PTBW values were significantly reduced at an increased angular velocity (P < 0.05). The PTBW of knee flexors was positively correlated with gait speed and cadence in the patients with HAM/TSP. The H/Q ratio but not E/F ratio was significantly decreased compared with the control. Our results indicated that the isokinetic trunk and knee muscle performance had reduced from the ambulatory stage, and suggested the deterioration in knee muscle performance to be associated with gait disturbance in walking HAM/TSP patients.

Intramedullary subependymoma of the cervical spinal cord: a case report with immunohistochemical study.

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.