Development of an MR-compatible configurable brush stimulation device.

In order to evaluate sensory disturbance, a subjective method is performed, so that the evaluation result is influenced by subjective factors. fMRI is used for observing brain activity objectively. Therefore the brain response to a stimulation measured by fMRI could become a useful identification tool for the objective evaluation of the sensory disturbance. The purpose of this study is to develop an MR-compatible sensory stimulation device capable of providing brush stimulation to several positions with separate modules, and to confirm the feasibility of the device by a basic operation experiment and an fMRI experiment. The developed device consists of both an MR-compatible stimulator placed inside the MRI room, a tube-rod mechanism and a driver placed outside the MRI room. The tube-rod mechanism is adopted for power transmission from the driver to the stimulator. Also, in order to provide the stimulation to several positions in the limited space, the device consists of the stimulation module and the positioning module that moves the stimulation module. For the basic operation experiment, we measure a variation of the automated and manual brush stimulation period. For the fMRI experiment, the brush stimulation is provided to the middle fingertip and the palm of a subject in a trial using the developed device. As a result, the standard deviations of the automated brush stimulation period is less than 7.0 ms. This result was smaller than that of the manual stimulation period. Also, the brush stimulation to the fingertip and the palm activated the somatosensory areas respectively. In conclusion, we confirmed the feasibility of the developed device through the experiments.

Multiple-slice magnetic resonance imaging can detect visceral adipose tissue reduction more accurately than single-slice imaging.

BACKGROUND/OBJECTIVE: Imaging methods by magnetic resonance imaging are being increasingly used to quantify visceral adipose tissue (VAT), but there is no clear consensus as to a standardized protocol. We compared the ability of two commonly used imaging protocols (multiple slice versus single slice) to detect changes in VAT with diet or exercise. SUBJECTS/METHODS: We utilized data from the participants who completed our diet (n=22) or exercise (n=35) based weight-loss interventions. The intervention mainly comprised of weekly dietary modification sessions or aerobic exercise sessions over 12 weeks. Multiple-slice images obtained from T9 to S1 and a single-slice image at L4-L5 were compared using the effect size of the VAT change. In addition, we calculated the sample size needed to compare the two imaging protocols' ability to detect significant changes in VAT. RESULTS: VAT and subcutaneous adipose tissue volumes and areas, and other anthropometry decreased significantly after both the diet and exercise interventions. For VAT, a single-slice image had a lower effect size (diet: 1.23; exercise: 0.49) than the multiple-slice images (diet: 1.81; exercise: 0.90). The sample size required for multiple slice was substantially lower than for the single-slice with both weight-loss interventions. CONCLUSIONS: The different image protocols may lead to different results in relative VAT changes. Furthermore, single-slice imaging required a substantially larger sample size than multiple-slice imaging, and for researchers to detect smaller changes in VAT with single-slice imaging, a larger sample size would be needed. Thus, multiple-slice imaging has advantages for assessing VAT change in future clinical research.

Difference in stretching of sarcomeres between medial gastrocnemius and tibialis anterior by tibial lengthening: an experiment in rabbits.

PURPOSE: To compare the degree of stretching of sarcomeres--in the medial gastrocnemius versus the tibialis anterior--acutely extended by tibial lengthening. METHODS: The right lower legs of 6 New Zealand White rabbits were acutely distracted by 6.3 mm using an external fixator, whereas the left lower legs served as controls. Immediately after distraction, the ankle was dorsiflexed at 50 degrees and the knee flexed at 140 degrees, with respect to the posture of resting on the ground. Both legs were immersed in 10% buffered formalin for fixation, and the medial gastrocnemius and tibialis anterior were removed. Length of the 2 sarcomeres was measured by a laser diffraction technique using isolated muscle fibre bundles. RESULTS: The mean lengths of sarcomeres in the medial gastrocnemius and tibialis anterior were 3.0 microm and 2.3 microm in the lengthened legs, and 2.4 microm and 2.1 microm in control legs, respectively. The degree of stretching of corresponding sarcomeres was therefore 25% and 10%, this difference being significant (p<0.01). CONCLUSION: Sarcomeres of the medial gastrocnemius are more stretchable than those of the tibialis anterior following tibial lengthening.

T-condylar fracture of the distal humerus in a three-year-old child.

A three-year-old girl suffered a T-condylar fracture of the distal humerus. Open reduction and pinning were performed. Three years after injury, there was no functional disturbance or radiographic evidence of avascular necrosis or epiphyseal growth arrest.

Dorsal plating for comminuted intra-articular fractures of the distal end of the radius.

Forty-one dorsally displaced intra-articular fractures of the distal radius were treated by open reduction and internal fixation with the dorsal Symmetry plates. The average age at the time of the injury was 49 years. An average follow-up period was 15 months. The final radial length averaged 11 mm, radial inclination 23 degrees, volar tilt 7 degrees, ulnar variance 1.5 mm, and articular incongruity 0.3 mm. According to the Gartland and Werly scales, 36 fractures were excellent and five were good. However, ulnar variance increased more than 3 mm during follow-up in eight patients, and volar tilt increased more than 5 degrees during follow-up in ten patients. Use of dorsal Symmetry plate is effective for unstable comminuted intra-articular distal radius fractures, but severely comminuted fractures may possibly undergo re-displacement post-operatively.

Central role of mitochondria and p53 in Fas-mediated apoptosis of rheumatoid synovial fibroblasts.

OBJECTIVE: Fas-mediated apoptosis is preferentially observed in synoviocytes of patients with rheumatoid arthritis (RA) and is associated with the pathophysiological process of RA. To clarify the molecular mechanisms of Fas-mediated apoptosis of RA synoviocytes, we investigated the role of the mitochondrial pathway and tumour suppressor p53 in this process. METHODS: Cultured synovial fibroblasts were prepared from RA patients. After treatment of RA synovial fibroblasts with anti-Fas monoclonal antibody, the expression levels of activated caspase-9 and -3, Bid cleavage, cytochrome c release and phosphorylation of p53 at Ser15 were assessed using immunoblot analysis. The mitochondrial membrane potential (DeltaPsim) was evaluated with a fluorescence-based detection assay. Apoptotic cells were determined by a DNA fragmentation assay in the presence or absence of caspase inhibitors. Expression of p53-regulated apoptosis-inducing protein 1 (p53AIP1) was measured by real-time PCR. RA synovial fibroblasts stably transfected with a dominant-negative (DN) p53 were prepared in order to investigate the role of p53 during Fas-induced apoptosis. RESULTS: Fas ligation induced Bid cleavage, loss of DeltaPsim, cytochrome c release to the cytosol and activation of caspase-9 and -3 in RA synovial fibroblasts. Treatment with a caspase-9-specific inhibitor almost completely inhibited Fas-mediated apoptosis. Moreover, p53 activation after Fas ligation was evidenced by its phosphorylation at Ser15 and up-regulation of the p53 target gene p53AIP1. Fas-mediated apoptosis was significantly suppressed by anti-sense p53 oligonucleotides and by p53DN. CONCLUSION: Our findings strongly suggest the involvement of mitochondria and p53 in Fas-mediated apoptosis of RA synovial fibroblasts.

Anterior dislocation of the subtalar joint: a case report.

We report a very rare case of anterior dislocation of the subtalar joint. Forceful supination of the foot and dorsiflexion of the ankle was considered the cause of the injury in this case. Closed reduction was successful for the talocalcaneal component of subtalar joint, although surgery was subsequently performed because of the residual subluxation of the midtarsal joint including the talonavicular component of subtalar joint and the associated fracture of the lateral process of the talus. Satisfactory results were shown at three-year follow-up.

Three epiphyseal fractures (distal radius and ulna and proximal radius) and a diaphyseal ulnar fracture in a seven-year-old child's forearm.

SUMMARY: The authors report a rare case of fracture separations at both ends of the radius combined with an epiphyseal and diaphyseal fracture of the ipsilateral ulna. A seven-year-old girl fell one story and sustained a closed injury of her forearm. A closed reduction was unsuccessful, and an open reduction was performed with three of the four fractures being secured with Kirschner wires. These wires were removed one month later, and range-of-motion exercises were started. Thirty months after surgery, both forearms were equal in length, although the proximal radial epiphyseal line appeared partially closed. Joint motions, including forearm rotation, were normal. Radiologically, the ulnar diaphysis and the radial neck were posteriorly convex 20 degrees and 18 degrees, respectively.

Analysis of calcium deposits in calcific periarthritis.

OBJECTIVE: To determine if hydroxyapatite (HAP), octacalcuim phosphate (OCP), or tricalcium phosphate (TCP) can be found in the calcium deposits in calcific periarthritis. METHODS: Thirty-six specimens from 34 patients who had acute inflammation and roentgenographically recognized calcification in soft tissue were analyzed. Twenty-three patients with calcific tendinitis in the shoulder and 11 with calcific periarthritis at other sites were included. We prepared 2 kinds of samples from each specimen; a dried sample (washed and dried calcific deposit), and a sample heated to 1,000 degrees C. All were analyzed by X-ray diffraction, Raman spectroscopy, infrared absorption spectroscopy, and X-ray fluorescence spectrometry for calcium and phosphorus molar ratio. Synthetic HAP was used as the control in each analysis. RESULTS: The X-ray diffraction patterns of all dried samples were similar to those of HAP and carbonate apatite. We found no diffraction patterns of OCP or TCP. However, an OH- group at 3570cm(-1) was observed with Raman spectroscopy for samples heated to 1,000 degrees C and synthetic HAP, but not for the dried samples. Infrared absorption spectroscopy also confirmed an OH- group for samples heated to 1,000 degrees C and synthetic HAP, and confirmed that dried samples contained carbonate. CONCLUSION: Calcium deposits are composed of carbonate apatite. HAP, OCP, and TCP were not identified in any deposits.

Type I and type III procollagen gene expressions in the early phase of ligament healing in rabbits: an in situ hybridization study.

The purpose of this study is to observe type I and type III procollagen gene expressions in the healing ligament using in situ hybridization histochemistry. The rabbit medial collateral ligaments were incised and harvested at 3, 7, 14, and 28 days postoperatively. The healing ligament showed increased expression of both procollagen genes through this period compared with the unoperated ligament. The peak expression level was observed at 7 or 14 days for type I and at 7 days for type III, respectively. The strongest expression of both genes was detected in the scar tissue created between the ends of the old ligament. Although type III procollagen gene expression was observed almost only in the newly created scar tissue, type I procollagen gene was expressed not only in the scar tissue, but also at the ends of the previously normal ligament. These results suggest that type I collagen synthesis begins shortly after ligament injury and occurs at the ends of the injured ligament as well as in the scar tissue, and that type III collagen is largely synthesized in the scar tissue around one week after injury but continues being synthesized for at least four weeks after injury.

Orientation and osteoarthritis of the lumbar facet joint.

Several studies have shown an association between sagittal orientation of the facet joint and degenerative spondylolisthesis. There is currently no information available on the association between orientation of the facet joint and osteoarthritis. This study examined the association between orientation and osteoarthritis of the lumbar facet joints. One hundred eleven consecutive patients underwent plain radiography and magnetic resonance imaging. These patients were divided into two groups: No Degenerative Spondylolisthesis Group (98 patients) and Degenerative Spondylolisthesis Group (13 patients). In the No Degenerative Spondylolisthesis Group, segments with higher grades of osteoarthritis showed more sagittal orientation of the facetjoints at the L3-L4 and L4-L5 levels. The facet joint was oriented significantly more sagittally in the Degenerative Spondylolisthesis Group than in the No Degenerative Spondylolisthesis Group at the L4-L5 and L5-S1 levels. The severity of facet joint osteoarthritis was significantly higher in the Degenerative Spondylolisthesis Group than in the No Degenerative Spondylolisthesis Group at the L3-L4, L4-L5, and L5-S1 levels. A significant association was found between sagittal orientation and osteoarthritis of the lumbar facet joints, even in patients without degenerative spondylolisthesis. Facet joint osteoarthritis, rather than spondylolisthesis, is the pathoanatomic feature that is associated with sagittal orientation of the facet joints in patients with degenerative spondylolisthesis.

Anatomy of the iliolumbar ligament.

Information is lacking in the literature on the precise anatomy of the iliolumbar ligament and its individual differences. The morphologic pattern, length, and width of the iliolumbar ligament were determined in 56 embalmed lumbosacral spines from human cadavers. It was possible to classify the iliolumbar ligament into two groups: Type A (74 ligaments), in which anterior and posterior ligaments had separate courses; and Type B (32 ligaments), in which anterior and posterior ligaments moved together as one band. The angle of the posterior iliolumbar ligament in Type A was oriented significantly more posteriorly than that in Type B. The posterior iliolumbar ligament was significantly shorter and oriented more posteriorly in male anatomic specimens than in female ones.

The relationship between disc degeneration, facet joint osteoarthritis, and stability of the degenerative lumbar spine.

Degenerative processes in the disc and facet joints affect the stability of the motion segment. The exact relations among disc degeneration, facet joint osteoarthritis, and the kinematics of the motion segment are not well defined in the literature. Magnetic resonance imaging and functional radiography of the lumbar spine were analyzed to examine the relations among segmental instability, facet joint osteoarthritis, and disc degeneration in patients with degenerative disorders of the lumbar spine. Seventy consecutive patients (mean age, 46 years) had both magnetic resonance imaging and flexion and extension radiographs of the lumbar spine. The lumbar instability was classified into abnormal tilting on flexion, rotatory instability in the sagittal plane, and translatory instability. Translatory instability was subdivided into anterior, posterior, and anteroposterior translatory instability. Disc degeneration as seen on T2-weighted sagittal images was classified into five grades. Facet joint osteoarthritis as seen on axial T1-weighted images was divided into four grades. This study revealed that the kinematics of the lumbar motion segment are affected by disc degeneration and facet joint osteoarthritis. Abnormal tilting movement on flexion and anteroposterior translatory instability both had negative associations with facet joint osteoarthritis. However, anterior translatory instability was positively associated with disc degeneration and facet joint osteoarthritis. Rotatory instability in the sagittal plane and posterior translatory instability were not associated with disc degeneration and facet joint osteoarthritis.

The interspinous ligament of the lumbar spine. Magnetic resonance images and their clinical significance.

STUDY DESIGN: A preliminary study of magnetic resonance features of the interspinous ligament in degenerative lumbar spine. OBJECTIVES: To classify the magnetic resonance imaging features of the interspinous ligaments in relation to the patient's age, disc degeneration, and radiographic instability. Magnetic resonance imaging also was correlated with the histologic findings of the interspinous ligaments. SUMMARY OF BACKGROUND DATA: As reported, rupture of the interspinous ligament frequently is found in the degenerative lumbar spine. However, little information is available in the literature on imaging assessment of the interspinous ligament in degenerative lumbar disorders. METHODS: In this study, 24 interspinous ligaments at L1-L2 or L2-L3 from 15 patients with nondegenerated discs were selected to represent normal magnetic resonance features of the interspinous ligament, and 38 patients with the mean age of 49 years underwent functional radiography and magnetic resonance imaging. The magnetic resonance features of the interspinous ligament were classified into five categories according to their signal intensities: Type 1A (low intensity on T1- and T2-weighted images without hypertrophy of the spinal process); Type 1B (same signal pattern as in Type 1A with hypertrophy of spinal process); Type 2 (low intensity on T1- and high intensity on T2-weighted images); Type 3 (high intensity on T1-weighted images); and Type 4 (others). Seven patients with variable patterns of the interspinous ligament were selected to undergo histologic examinations. RESULTS: Of the interspinous ligaments considered normal, 80% were classified as Type 1A. There were 14 Type 1A, 30 Type 1B, 19 Type 2, 16 Type 3, and 20 Type 4 ligaments. The mean age and disc degeneration grade of the patients with the Type 1B ligaments was significantly higher. Instability was found to be associated with Type 2 interspinous ligaments (7 of 19), whereas instability rarely was noted in Types 1A (1 of 14) and 1B (1 of 30) ligaments. The histologic examination revealed that chondrometaplasia and necrotization of fiber bundle predominated in Type 1B, proliferation of cells and vascular invasion in Type 2, fatty degeneration in Type 3 ligaments. CONCLUSIONS: The magnetic resonance imaging characteristics may be helpful in assessing normal or pathologic changes in the interspinous ligaments.

A micronucleus assay in sea urchin embryos.

We have developed a micronucleus assay for use in sea urchin embryos. The embryos at the early blastula stage (about 256 cells) were exposed to genotoxic chemicals overnight until control embryos have reached the gastrula stage. Then all embryos were suspended in 1 M urea, dissociated by pipetting, and fixed with methanol:acetic acid (9:1). The preparations were air-dried and stained with acridine orange. The test chemicals (mitomycin C [MMC], vinblastine and 1-beta-D-arabinofuranosylcytosine [Ara C]) induced clear micronuclei dose-dependently. The maximum frequency induced with MMC was 2-3% in Clypeaster japonicus and 1-2% in Hemicentrotus pulcherrimus.

The relationship between facet joint osteoarthritis and disc degeneration of the lumbar spine: an MRI study.

The role of MRI in assessing facet joint osteoarthritis is unclear. By developing a grading system for severity of facet joint osteoarthritis on MRI, the relationship between disc degeneration and facet joint osteoarthritis was determined. The accuracy of MRI in assessing facet joint osteoarthritis against CT was 94%. Under 40 years of age, the degree of disc degeneration varied among individuals. Over the age of 60, most of the discs were markedly degenerated. Under 40 years of age osteoarthritic changes in facet joints were minimal. Over the age of 60, variable degrees of facet joint osteoarthritis were observed but some facets did not show osteoarthritis. No facet joint osteoarthritis was found in the absence of disc degeneration and most facet joint osteoarthritis appeared at the intervertebral levels with advanced disc degeneration. Disc degeneration is more closely associated with aging than with facet joint osteoarthritis. The present study supports the hypothesis that "disc degeneration precedes facet joint osteoarthritis", and also supports the concept that it may take 20 or more years to develop facet joint osteoarthritis following the onset of disc degeneration.

Relationship between morphology of iliolumbar ligament and lower lumbar disc degeneration.

Previous imaging studies have shown little difference in the degree of disc degeneration between L4-L5 and L5-S1. We hypothesized that because the morphology of the iliolumbar ligament affects the stability of the lumbosacral junction, then it could determine the lower lumbar disc degeneration. Fifty-three male and 47 female patients were classified into three groups according to their disc degeneration grade-those in whom the L5-S1 disc was less degenerated (group A), more degenerated (group B), and equally degenerated (group C) compared to the L4-L5 disc on T2-weighted magnetic resonance images. The length and direction of the anterior and posterior iliolumbar ligaments were measured on T1-weighted axial images. The iliolumbar ligament was shorter in group A than in group B or C, and was oriented significantly more posteriorly in group A than in groups B or C. The morphology of the iliolumbar ligament, especially its length and direction, can be a factor influencing the development of disc degeneration at L4-L5 and L5-S1.

Para-articular chondroma and osteochondroma of the infrapatellar fat pad: a report of three cases.

We report three cases of para-articular chondroma and osteochondroma in the region of infrapatellar fat pad. All three lesions were resected and examined histologically. Two of them were primarily cartilaginous with a lobular pattern internally, and one uniformly osseous with peripheral cartilage. We conclude that these lesions are not the same. The former should be designated para-articular chondroma after Jaffe and the latter, osteochondroma.