Masaaki Uesugi

The correlation of diffusion-weighted magnetic resonance imaging in cervical compression myelopathy with neurologic and radiologic severity.

Study Design. A retrospective evaluation of diffusion-weighted imaging, apparent diffusion coefficient (ADC) maps, and T2-weighted images in patients with cervical compression myelopathy. Objective. To correlate high signal intensity on ADC maps and T2-weighted images to neurologic severity and radiologic spinal cord compression. Summary of Background Data. Previous studies indicated that the ADC map was more sensitive in detection of cervical compressive myelopathy than T2-weighted imaging. The relationship to neurologic severity has not been previously published. Methods. In 100 patients with or without cervical compressive myelopathy, the magnetic resonance appearance of the spinal cord on ADC maps and T2-weighted images was evaluated independently by 2 readers. On the basis of the presence or absence of abnormality, patients were categorized into 4 groups by type of intramedullary change. The degree of canal compression and the Japanese Orthopedic Association (JOA) score for cervical myelopathy were compared among the 4 types. Results. The type I group consisted of 32 patients without signal change on either ADC maps or T2-weighted images. The type II group had 33 patients with high signal intensity only on the ADC map. The type III group contained 28 patients with high signal intensity on both the ADC map and the T2-weighted images. The type IV group comprised 7 patients with high signal intensity only on T2-weighted images. The degree of canal compression and the JOA scores were significantly different among the 4 groups (P < 0.005). Most type III (25 of 28) and type IV (7 of 7) patients had severe cord compression. Average JOA scores in each type were (I) 16.0, (II) 14.7, (III) 11.7, and (IV) 8.7. Conclusion. ADC maps demonstrated internal changes in the early stages of chronic spinal cord compression, but had limitations for the detection of intramedullary changes in late-stage myelopathy.

Effectiveness of a Lumbar Support Continuous Passive Motion Device in the Prevention of Low Back Pain During Prolonged Sitting

Study Design. Subjective ratings of discomfort were compared between a fixed lumbar support and lumbar support continuous passive motion (CPM) device. Objective. To compare a fixed lumbar support with a lumbar support CPM device during prolonged sitting. Summary of Background Data. To prevent low back pain during prolonged sitting, an inflatable lumbar support CPM has been developed. There are no studies that compare static lumbar support with lumbar CPM using the same pressure in the cushions. Methods. A total of 31 male volunteers without low back pain sat in the same chair for a 2-hour period on each of 3 consecutive days under 3 randomized test methods: 1, no lumbar support; 2, static lumbar support; and 3, lumbar support CPM. Each subject rated low back pain, stiffness, fatigue, and buttock numbness on a visual analog scale (VAS). Fixed lumbar support and CPM device were compared with a same inflation pressure in the cushion. For 10 subjects, the whole body posture and the pressure distribution changes of the human-seat interface during CPM were evaluated. Results. Compared with no lumbar support, a significant improvement in VAS scores for low back pain, stiffness, and fatigue was obtained with both static lumbar support and with lumbar support CPM (P < 0.005). A significant (P < 0.005) improvement for buttock numbness was obtained only with lumbar support CPM. There were no statistical differences in all VAS scores between the fixed lumbar support and the CPM device. A forward rotation of the pelvic region was obtained during inflation of the cushion during CPM. Significant differences (P < 0.05) were found between cushion inflation and deflation periods both in contact areas and in the peak pressures at the human-seat interface. Conclusion. There were no statistical differences in the subjective ratings of discomfort between the fixed lumbar support and the CPM device.

Does the Fists-on-Clavicles Position Represent a Functional Standing Position?

Study Design. Prospective analysis of sagittal vertical axis (SVA) on lateral spine radiographs using 3 different arm positions. Objective. To examine whether fists-on-clavicles position represents a functional standing position. Summary of Background Data. Radiographic visualization of spinal and pelvic sagittal morphology is difficult during relaxed standing because of interference from the arms; however, standing with arms forward-flexed results in a negative shift in SVA. The fists-on-clavicles position was proposed to provide a more functional sagittal profile and adequate visualization of the spine. No existing study compares the SVA between the fists-on-clavicle and relaxed standing positions. Methods. The SVA was measured on standing lateral radiographs of 14 healthy subjects using 3 different arm positions: relaxed with arms-at-side, arms forward-flexed to 45° (shoulder flexion [SF]), and fists-on-clavicles. Results. The mean SVA with relaxed standing was 1.4 ± 1.9 cm. SF produced a significant SVA negative shift (−3.7 ± 2.3 cm, P < 0.001). The fists-on-clavicle position resulted in a reduced but significant SVA negative shift (−2.3 ± 2.1 cm, P < 0.001) compared with relaxed standing. Conclusion. Although the fists-on-clavicles position was better than SF in reducing the SVA negative shift, a significant negative shift did occur in the fists-on-clavicle position compared with relaxed standing.

Inhibition of lung metastasis of osteosarcoma cell line POS-1 transplanted into mice by thigh ligation

Using a model with external ligation of the thigh, the effect of ischemia-reperfusion injury on tumor growth and the activity of lung metastasis was investigated in mice inoculated a spontaneous murine osteosarcoma cell line (POS-1) in vivo. POS-1 cell suspension was inoculated into the right hind footpad of 70 mice. Four weeks after inoculation, the ipsilateral thigh was ligated for 3 h in 15 mice and the contralateral thigh in 15 mice. Another ten mice were inoculated with POS-1 without ligating the thigh. The number of metastatic foci on the lung surface 6 weeks after inoculation was 2.29+/-0.98 (mean+/-SE) foci/lungs in mice with ipsilateral ligation and 6.25+/-2.41 in mice with contralateral ligation, which were significantly lower than control (13.40+/-1.42 in mice no ligation) (P<0.01). The number of metastatic foci on the lung surface in mice with intraperitoneal injection of superoxide dismutase (SOD) and catalase was 3.25+/-0.65 (mean+/-SE) foci/lungs in mice with ligation which was significantly greater than that in mice without SOD and catalase injection 1.29+/-0.97 (P=0.04). Cell viability was 9.12+/-4.07% with 100 microM H(2)O(2) in 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay. It revealed that at concentrations of 100 microM H(2)O(2) or higher was cytotoxic to POS-1. In cell invasion assay, the number of invading cells with 10 microM H(2)O(2) was 2.80+/-0.53 cells/field, which was significantly lower than control (5.93+/-0.18) (mean+/-SE), indicating that low-dose H(2)O(2) suppressed invasion of POS-1. These results suggested that reperfusion injury had selective cytotoxicity to POS-1 through producing reactive oxygen species. Activated oxygen was considered to inhibit the regional growth and the ability of lung metastasis of POS-1 cells.

Acceleration of lung metastasis by up-regulation of CD44 expression in osteosarcoma-derived cell transplanted mice

The effect of CD44-phenotypic expression on metastasis to the lung was studied using a spontaneous murine osteosarcoma-derived cell line, POS-1, stimulated with lipopolysaccharide (LPS). POS-1 cells were inoculated into the hind paws of 20 C3H/HeJ mice and produced a visible mass in all mice in 5 weeks, and these transplanted tumors resulted in lung metastasis in all mice. The number of metastatic foci in the lungs was 12.0+/-2.1 (mean+/-SD) with LPS-stimulated cells, which was significantly higher than that of unstimulated cells (5.8+/-1.4; N=10 for each; P<0.05). Hyaluronate (HA), a ligand of CD44, inhibited a number of lung metastases in a dose-dependent manner (0.5% HA, 3.0+/-1.1; 0.005% HA, 5.1+/-1.5; without HA, 8.6+/-1.7; N=10 for each; P<0.05, each group with HA versus the group without HA). Adhesion assay by coculturing POS-1 cells and lung microvascular endothelial cells on culture plate showed that the adhesion was significantly lower in HA treated POS-1 than those without HA (1.18+/-0.12 and 2.74+/-0.17, respectively, P<0.05). These results suggest that lung metastasis was accelerated by up-regulation of CD44.

Clinical results of intrapedicular partial pediculectomy for lumbar foraminal stenosis.

Design A retrospective case study of the use of intrapedicular partial pediculectomy (IPPP) to treat lumbar foraminal stenosis. Objective To evaluate the clinical results of lumbar foraminal stenosis treated with IPPP. Summary of Background Data There is no gold standard for the surgical treatment of foraminal stenosis, which occurs in 8% of surgical cases of lumbar degenerative diseases. Methods A total of 26 patients who were followed up for a minimum of 2 years after IPPP for foraminal stenosis, were included in this study. The study group consisted of 20 men and 6 women with an average age at surgery of 63.3 years (range: 42 to 83) and a mean follow-up of 5.5 years (range: 2 to 11). The affected levels were L3/4 in 1 patient, L4/5 in 7, and L5/S1 in 18. Bilateral IPPP at L5/S1 was performed in 2 patients. The clinical results were evaluated according to the Japanese Orthopedic Association (JOA) scoring system. Results Two patients required revision surgery to correct insufficient decompression. In the remaining 24 patients, the average JOA scores were 6.7 (range: −1 to 10) before surgery, 12.4 (range: 9 to 15) 3 months after surgery, 12.3 (range: 9 to 15) 1 year after surgery, and 11.7 (range: 5 to 15) at the final follow-up. The average recovery rate was 62.1% (range: 40.0% to 81.3%). Conclusions This follow-up study confirms that IPPP affords long-lasting improvements in leg symptoms for patients with lumbar foraminal stenosis.

Optimal arm position for evaluation of spinal sagittal balance.

Study Design Analysis of sagittal vertical axis (SVA) on lateral spine radiographs in healthy normal volunteers. Objectives To determine the optimal arm position with the smallest negative shift in SVA. Summary of Background Data Radiographic visualization of spinal and pelvic sagittal morphology is difficult with the participant in a relaxed standing position because of interference from the arms. Standing with shoulder flexion (SF) results in a negative shift in SVA. The fists-on-clavicles (FC) position reduces the negative shift in SVA seen in SF, but only by 25%. The best arm position to produce the smallest negative shift in SVA has yet to be determined. Methods The SVA was measured using standing lateral radiographs of 21 healthy participants. Five different arm positions were used: relaxed with arms at sides (RLX), arms flexed to 45 degrees (SF), FC, arms folded across the chest (FA), and arms relaxed in front with hands loosely clasped (FHC). Negative shifts in SVA resulting from the SF, FC, FA, and FHC arm positions were compared. Results The mean SVA with RLX was 2.3±2.0 cm. The other arm positions resulted in a significant negative SVA shift compared with RLX (P<0.001). Mean negative shifts were −5.1±1.6 cm for SF, −3.9±1.5 cm for FC, −3.1±1.1 cm for FA, and −1.8±1.7 cm for FHC. The FC position reduced negative SVA shift seen in the SF arm position by 24%, FA by 39%, and FHC by 65%. The FHC position resulted in a significantly reduced SVA negative shift (P<0.001) compared with the FC, FA, and SF positions. Conclusion FHC that produced the least negative shift in SVA, is the best arm position for SVA measurement.

Predictive value of serum immunosuppressive acidic protein for lung metastasis after amputation of murine osteosarcoma of the lower limb

A spontaneously occurring murine osteosarcoma cell line (POS-1) was inoculated into the footpads of 88 mice. In 59 mice, the tumor-bearing leg was amputated at 1, 3, 5, or 7 weeks after inoculation and the mice sacrificed at 9 weeks. Lung metastasis was observed in 82.6-100% of the mice undergoing leg amputation at 5 or 7 weeks after inoculation. There were no lung metastasis in the mice amputated at 1 or 3 weeks. The serum immunosuppressive acidic protein (IAP) concentration showed a significant increase at 5 or 7 weeks after inoculation (P<0.005 and P<0.0005, respectively). When amputation was done 5 weeks after inoculation, the serum IAP concentration increased further to 5.9 times the pre-amputation level 1 week after the amputation. The IAP concentration increased only 1.3-fold in the control group without inoculation. Thus, a high serum IAP concentration before amputation and a further increase after amputation were indicators of lung metastasis in this mouse model of osteosarcoma.

Use of dynamic spinal brace in the management of neuromuscular scoliosis: a preliminary report.

Neuromuscular scoliosis is difficult to treat with braces because the collapsing trunk with the spinal deformity cannot tolerate the hard materials used for most orthoses. The dynamic spinal brace (DSB) is a novel three-point support brace used in Japan. We present our preliminary findings of 52 pediatric patients with neuromuscular scoliosis treated using DSBs. A positive correlation was found between the Cobb angle at the initiation of bracing and the degree of scoliosis progression. We concluded that DSBs may be effective for early-stage scoliosis. We also found that DSB improved sitting stability and thereby caregiver satisfaction.

Upregulation of CD44 expression on bovine articular chondrocytes induced by synthetic lipid A

Abstract The purpose of the study reported in this article was to investigate effects of synthetic lipid A on the expression of adhesion molecule CD44 on bovine articular chondrocytes. Full-thickness bovine articular cartilage was dissected from the carpometacarpal joints of 24 cows. Cartilage pieces were enzymatically digested to liberate chondrocytes. The chondrocytes were incubated in the presence of synthetic lipid A in suspension culture. Cell characteristics and binding of monoclonal antihuman CD44 antibodies were assessed with a flow cytometer. The expression of CD44 mRNA in chondrocytes was detected by reverse transcription-polymerase chain reaction (RT-PCR) technique. PCR products were quantified with a charge-coupled device image sensor. The percentage of CD44-positive chondrocytes was 42.2% ± 12.0%, 51.7% ± 6.8%, and 51.1% ± 5.0%, in the presence of lipid A at 0.25 μg/ml, 2.5 μg/ml, and 25 μg/ml, respectively, whereas it was 39.2% ± 8.9% in the absence of lipid A. In flow cytometry, two subpopulations of chondrocytes were found in each of five separate experiments, one with smaller number of forward scatter (FS) and the other with larger number of FS. The percentage of CD44-positive cells was 24.8% ± 8.5% in the subpopulation with smaller number of FS and 31.9% ± 6.4% in the subpopulation with larger number of FS at time 24 h after incubation. The bacterial component, lipid A, upregulated expression of CD44 on articular chondrocytes.