Nihon Seikeigeka Gakkai zasshi最新文献

In order to clarify the changes seen in the new acetabular roof produced by Chiari pelvic osteotomy, we performed histological investigations post-operatively, as well as arthrography and arthroscopy before and after the operation. Plain X-rays showed an osseous step between the original surface and the new acetabular roof. Arthrography demonstrated no step between the original acetabular cartilage and the surface of the newly formed acetabular roof. At arthroscopy, the surface of the new acetabular roof could be seen to be covered by a soft white tissue. Histological specimens were taken from the new acetabular roof. Examination revealed that the superficial layer consisted of some oval shaped cells with an extracellular matrix slightly stained by safranin O, but not by anti-human type II collagen antibodies. In the deepest layer, there was cartilage tissue consisting of cartilage-like cells and an extracellular matrix which was stained by safranin O and by anti-type II collagen antibodies. However, the staining intensity of this cartilage tissue was less than that of hyaline cartilage, and the direction of collagen fibers could be clearly seen. These results suggested that the tissue covering the new acetabular roof had no ability to change into hyaline cartilage, despite the superficial layer creating a smooth surface. It was suggested that the bony modification of the new acetabular roof resulted from enchondral ossification of the deepest layer.

Occasionally, the outcome from laminoplasty for cervical spondylosis is disappointing despite an adequate operation. Before surgery, it is difficult to diagnose the pathological extent of the involvement of the spinal cord. The purpose of this study is to determine the efficacy of magnetic resonance imaging (MRI) and of the motor evoked potentials (MEPs) for the indication of the surgery and prognosis. Retrospectively, we investigated the MEPs and the MRI image of 31 patients in surgery for cervical myelopathy, involving 21 cases with cervical spondylosis and 10 cases with ossification of the posterior longitudinal ligamentum, and compared the findings from those with a poor outcome (n = 31) with the findings from those with a good outcome (n = 32). The MEPs from the thenar muscle and the tibialis anterior were evoked by transcranial magnetic brain stimulation. In the poor-outcome patients, the spinal canal was narrow and lumbar spinal canal stenosis was seen in 5 cases which required lumbar laminectomy. Before operation, the MEPs from the thenar muscle could not be evoked in 5 cases while there was a remarkably prolonged central motor conduction time in the other 26 cases. MRI revealed the deformed spinal cord in the involved area, and the signal intensity of the involved spinal cord in the T2 weighted image was remarkable high. The signal intensity ratio was significantly higher in the poor-outcome patients than in the good-outcome patients. This study suggested that a high signal intensity in the T2 weighted image and a prolonged conduction time or absence of MEPs largely corresponded to the clinical and other investigative features of myelopathy responsible for a poor outcome.

An image analyzer which combines a digitizer and a computer is widely employed in bone histomorphometrical evaluation. With this method, however, all regions of determination are traced manually so that considerable time is consumed when many preparations are measured. To resolve this problem, we have developed an automatic program for rapid and quantitative measurement of many bone histomorphometrical parameters using a computed color image analyzer. The bone volume (BV), tissue volume (TV), osteoid surface (OS), and the bone surface (BS) of rat tibia metaphysis were measured by this automatic method, and by the manual method using an image analyzer. The correlation coefficient between both methods in measuring BV/TV was 0.98 and in measuring OS/BS was 0.96. The reproducibility and accuracy of both methods for these parameters were similar. The time required for the automatic method was much shorter than that for the manual method. Various parameters of the tibial metaphysis, lumbar vertebral body, and femoral mid-diaphysis in ovariectomized rat (Fischer) measured by this method were in good agreement with values reported previously.

An experimental study was performed to evaluate the effects of sodium fluoride (NaF) on bone mineral density (BMD) and bone strength in rat. Sixty-nine female Wistar rats aged 12 months were used. Ovariectomy was carried out in 59 rats, and 3 of these were sacrificed to confirm osteopenia at 6 months after the ovariectomy. Twenty-eight of the remaining 56 rats were given NaF. Half of this NaF Group was given high-Ca feed and the other half was given normal feed. And one half of the High-Ca Group and one half of the Normal Feed Group were given vit. D. The other 28 rats in the Non-NaF Group were given high-Ca and vit. D as in the NaF Group. Accordingly, eight groups were created, each with seven rats. All were treated for 9 weeks. An additional 10 rats were used for control. At 6 months after a sham operation, three of these controls were sacrificed to confirm non-osteopenia. The remaining seven controls were given normal feed for 9 weeks. Therefore, there was total of 9 groups (69 rats). At eight months after the surgery (ovariectomy or the sham procedure), both femurs were removed from each rat. The BMD was measured over the entire femur by the DXA method. Bone strength was measured by three-point bending, compression and penetration tests. BMD was found to be higher in the NaF Group than in the Non-NaF Group or Control Group, and was highest in the NaF-high-Ca feed Group. In the bone strength test, the NaF Group scored higher than the Non-NaF Group. In the three-point bending and penetration tests, the NaF-high-Ca feed Group was highest. A linear correlation was found between the BMD and bone strength. There was no effect produced by the administration of the vit. D on the BMD or bone strength. In conclusion, the experimental administration of NaF, and of high-Ca feed, increased BMD and bone strength.

This study investigated the stress distribution in the L1 vertebra under a vertical axial load. Five normal spinal units (T12-L2) were obtained from embalmed human cadavers, to measure the surface strain in the L1 vertebra. Stress screening using a brittle-coat was prepared beforehand, then fourteen sites on the lateral half of the surface on the L1 vertebra were carefully chosen to install rosette strain gauges. A vertical axial load was applied up to 1471 N in two degrees of flexion, in the neutral position, and in two degrees of extension of the intact spine, and in the neutral facetectomized spine. The strain at each site was measured with strain gauges, then the tensile, compressive and shear strain values were calculated. Cracks in the brittle-coat showed the strain concentration in the base of the pedicles and rims on the superior vertebral body. Analysis of the data by strain gauge showed that the amount of strain at the rims on the superior vertebral body was greater than that at the inferior rims in the three positions of the intact spines, with a statistical significance. These strains led to a burst in the superior vertebral body rims. As for the posterior elements, the inner surface of the laminas received a tensile strain only, while the principal strain on the outer surface of the laminas was a compressive strain, in the directions parallel to the laminas. These strains led to a transformation in the posterior elements, leading to widening in the interpedicular distance and a fracture in the inner surface of the lamina. These results showed the first lumbar vertebra was easily mechanically injured by a Denis type B burst fracture. Also this study demonstrated that the pedicles were the pathway for load transmission.

In order to evaluate the morphological features of the proximal femur in the Japanese, 100 femora of normal Japanese subjects (normal group) and 60 femora of 43 Japanese patients with secondary osteoarthrosis of the hip (OA group) were analyzed using CT images. The scans for the dried bones (normal group) were done at a setting of 80 kV and 20 mA, for 2 sec duration. The scans were reconstructed using the soft tissue algorithm built into the GE-9800 scanner. The patient scans (OA group) were done at 120 kV and 170 mA also for 2 sec duration, and reconstructed using the same bone algorithm. The results were as follows: 1) Thinning of the femoral cortex occurred in normal females over 60 years of age. 2) The canal flare index at the proximal part of the femoral diaphysis was negatively correlated with the canal diameter at the isthmus. The index at the upper part was greater than that at the lower part. The two groups showed no statistical difference in this index. 3) In the metaphysis, the canal flare index at the anterior portion was twice that at the posterior portion. In absolute terms, the OA group had a reduced flare or curve along the medial portion. 4) In cross-section, the canal shape of the diaphysis was more elliptical in the OA group than in the normal group. The longitudinal axis of the canal was directed more sagittally in the OA group than in the normal group.

A total of 210 cervical intervertebral discs were taken at autopsy from 36 cadavers, and underwent both magnetic resonance imaging (MRI) and discography to compare their diagnostic efficacies for investigating degenerative changes in the cervical spine. The age of the subjects had ranged from 43 to 92 years with an average of 68.1 years. Following the autopsy, MRI and discography were performed on the excised cervical spinal column, and the specimen was then prepared for histological examination. The findings were compared with those of the lumbar spine that had previously been reported by Yasuma et al. on 1238 lumbar discs from 197 cadavers ranging in age from 11 to 92 years. The results were as follows: 1) Low intensity in the T2-weighted MRI was well correlated with histological degeneration in the cervical disc disc. 2) The rate of appearance of the posterior protrusion of the cervical disc on the MRI was in accordance with the degree of histological disc degeneration, but it did not always correspond with histological posterior protrusion. There was a remarkably high incidence for false-positive posterior protrusion on the MRI, which should be kept in mind on reading the MRI. 3) In the comparison of the MRI with the discography, a certain positive correlation was found as for disc degeneration, but not in complete accordance. 4) There was a considerable difference in the patterns of degeneration and in posterior protrusion of the discs between the cervical spine and the lumbar spine. The posterior protrusion in the cervical disc was more likely related to horizontal fissure and hyalinization of the posterior annulus, while posterior protrusion in the lumbar disc was often related to reversed orientation of the bundles and myxomatous degeneration of the posterior annulus. This difference was attributed to the difference in the mechanical properties of the cervical and lumbar spines.

Analysis was conducted on calcific deposits from 5 patients with calcific periarthritis. These calcific deposits were dried, immersed in hydrazine, or heated to 1000 degrees C for 1 hour, to prepare 3 kinds of samples. The samples were classified as dried samples, hydrazine-deproteinated samples, or as heated samples. All samples were analyzed by X-ray diffraction (XRD). Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy (Raman), and by electron probe microanalysis (EPMA). Although the XRD patterns of the dried samples and of the deproteinated samples were similar to that of hydroxyapatite (HAp), it was still unclear whether or not the calcific deposits were HAp. FTIR then revealed that the dried samples contained carbonate. Raman showed that the dried samples and the deproteinated samples do not have an OH-group. The dried samples were then heated to 1000 degrees C for one hour and analyzed by all 4 methods. The heated samples were found to be HAp. From these results, the calcific deposits from the 5 patients with calcific periarthritis were found to be carbonate apatite: Ca10-x-y/2 (PO4)6-x (CO3) x (OH) 2-y (CO3)y/2.nH2O.

The purpose of this study was to determine the isometric points for anterior cruciate ligament (ACL) reconstruction and to investigate notch impingement with isometric reconstruction. The length pattern of ACL was assessed by three-dimensional bi-plane X-ray photogrammetry for determining the isometric point for ACL reconstruction. The isometric points were studied in six fresh cadaveric knees with no injury in any ligament. Five femoral and four tibial attachment sites were selected for intra-articular reconstruction. In each knee, 20 different combinations were studied. For extra-articular reconstruction, three femoral and three tibial sites were selected. In these knees, nine different combinations were studied. One isometric point for intra-articular ACL reconstruction was a combination of the 5-mm superior posterior point from the femoral attachment of the ACL and the center point of the tibial attachment. The other was a combination of the anterior-proximal edge of the femoral attachment and anterior edge of the tibial attachment. There were no isometric points for extra-articular ACL reconstruction. To investigate notch impingement, eight cadaveric knees were studied. One femoral and three tibial attachment sites were selected. For the reconstructed ligaments, 8-mm and 10-mm cables were used. In each cadaveric knee, six different conditions were studied. When the tibial hole was positioned in the center of the attachment of ACL with an 8-mm graft, then notch impingement did not occur. When the tibial drill holes were positioned in a more anterior position, then notch impingement occurred in all the cadaveric knees in which an 8-mm graft was used. With the 10-mm grafts, notch impingement occurred in all three bony tunnel conditions. In these conditions, notch impingement occurred widely from the medial side of the roof to the wall of the lateral femoral condyle. Thus, if the graft diameter is greater than 8 mm, adequate notch plasty must be performed.

A bone resorption model in which osteoclasts were selectively activated was made by administering vitamin A--a bone resorption agent--to juvenile thyroparathyroidectomized rat. Inhibition of bone resorption by YM-175--a third generation bisphosphonate--was studied using this model based on bone histomorphometry of the proximal part of the tibia and on biochemical data. Six-week-old male SD rats were thyroparathyroidectomized (TPTX). On the 11th day following TPTX they were treated with vitamin A (etretinate). In the calcitonin group, salmon calcitonin or its vehicle was added, and in the bisphosphonate group, YM-175 or its vehicle was added. They were sacrificed on the 21st day following TPTX. Calcitonin was used to confirm its inhibitory activity of bone resorption in this model. Cancellous bone in the epiphysis was subjected to histomorphometry using tetracycline labeling or TRAP staining, and the number of primary trabeculae at the metaphysis was counted to evaluate bone resorption activity. Serum calcium, phosphorus, urinary calcium, phosphorus, pyridinoline and deoxypyridinoline were measured for biochemical analysis. YM-175 did not change any bone formation parameters in the histomorphometry of the epiphysis, while it significantly decreased resorption parameters both histomorphometrically and biochemically. Primary trabeculae at the metaphysis were found to be longer and denser after administration of YM-175. The effect of YM-175 as a bone resorption inhibitor was observed even in a short duration experiment. There was no damage to mineralization, and no inhibiting effect was observed on bone formation. Similar results were observed by calcitonin. YM-175 was concluded to be an inhibitor of bone resorption caused by vitamin A administration.