ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

An animal model of intervertebral disc degeneration induced surgically by ventral nuclear herniation in the rabbit produces morphologic changes of disc degeneration. Histologic characteristics and proteoglycan changes have been studied at various times after herniation. After injury, there was metaplasia into fibrocartilage originating from the cells along the margins of the annular wound, with proliferation of cells changing almost the entire disc space into fibrocartilage. A vertebral osteophyte occurred through an endochondral ossification sequence. Aggregating proteoglycans had two periods of repletion in the early course of degeneration. The water content of the disc was rapidly but only transiently restored in the first two days after herniation, whilst the changes in the total proteoglycan content of the disc paralleled these changes. Hyaluronic acid content decreased rapidly after herniation, but the size of the proteoglycan monomers did not change with degeneration. It is suggested that loss of confined fluid mechanics signals an abortive repair attempt rather than that the biochemical changes in proteoglycans initiate disc degeneration.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The pathways of material transfer to the intervertebral disc were studied in adult dogs by measuring diffusion of hydrogen molecules in the nucleus pulposus before and after disruption of the route through the annulus fibrosus and before and after disruption of the end-plate route. The disruption of the end-plate route, even if the separation of the bone-disc interfaces was only in the central two-thirds of one side, caused significantly greater decrease in the rate of hydrogen washout than the disruption of the annulus route. Hitologically, the bone-cartilage interface was frequently perforated by marrow cavity and vascular buds. These findings suggest that the end-plate route is a major pathway for material transfer to the intervertebral disc.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The distribution of axial stress on the end-plate of the vertebral body has been measured by the aid of miniature piezoelectric pressure transducers in specimens of motion segments of the human vertebral column. The results indicate that the stress distribution depends essentially on the state of degeneration of the intervertebral disc and on the relative position of the adjacent end-plates. Furthermore lumbar and thoracic motion segments show a different behaviour. The measured results relate to the problem of the stress dependent deformation of the growing vertebra, the codfish shape of the osteoporotic vertebra and to the mechanism of degeneration of the intervertebral disc.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

Abnormalities of intervertebral joint motion including hypermobility, reduced mobility, torsional abnormality, and displacement of the center of rotation have been associated with degenerative change. However, measurement of these signs in plane X-ray films is handicapped by the three-dimensional motion and geometry of the spine. This study aimed to relate three-dimensional motion of the joints to their pathological state. We have used biplanar radiography to measure intervertebral motion during voluntary movements by patients with low back pain. Primary (or intentional) and coupled motions were measured by a refined technique, along with disc shear and facet joint motion. Abnormalities were found, especially in the “coupled” motions which were related to narrowed disc space, and to proximity to previous fusions. There was asymmetry of motion specific to joints with herniated nucleus pulposus.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

Cadaveric lumbar intervertebral joints were loaded simultaneously in torsion and compression, and load-deformation curves were obtained. These were repeated after each of the following structures were cut through in turn: the supra/interspinous ligaments, the apophyseal joint in compression, and the apophyseal joint in tension. From the differences in the curves, it was possible to deduce the role of each structure and of the intervertebral disc in resisting and limiting torsion. The results show that torsion of the lumbar spine is resisted primarily by the apophyseal joint that is in compression, although the intervertebral disc does play a major role. The capsular ligaments of the tension facet and the supra/interspinous ligaments are unimportant. The compression facet is the first structure to yield at the limit of torsion, and this occurs after about 1 -2° of rotation in joints with nondegenerated intervertebral discs. Much greater angles are required to damage the intervertebral disc, so torsion seems unimportant in the etiology of disc degeneration and prolapse.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

The moments generated in the lumbar spine by a weight lifter are balanced by moments generated internally by muscles and by the intervertebral ligamentous structures including the disc. Unique real number solutions have been obtained by a optimization technique minimizing shear and penalizing excessive muscle power. The model faithfully reproduces the electromyographic responses and all known experimentallydetermined values for muscle power and compression. The outputs can be used to calculate a realistic motion of the spine under various loads. The model suggests that in handling heavy loads, the stress at each intervertebral joint is identical and with maximal voluntary effort, the weight lifter does not exceed 67% of the ultimate strength of his tissues.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

Observations of the ranges of flexion of the lumbar interbody joints under standardized loading have been made before and after isolated floating fusions were performed. The observed effect was that the movement which had previously occurred at a free disc level was transferred preferentially to discs immediately adjacent to the fusion—usually, but not always, most of this movement being taken up by the disc immediately below the fusion. The implications of these observations for patients on whom a floating spinal fusion is to be performed are discussed. A clinical case is discussed in which a congenital fusion is associated with degeneracy of an immediately neighboring disc.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

To date no knowledge of the incidence of scoliosis in adults and its relationship to low-back pain is available. In order to arrive at an understanding of low-back pain in adult scoliosis, a study of 5000 intravenous pyelograms was performed. The incidence of lumbar and thoracolumbar curves was 2.9%. One hundred and fifty-nine of the 189 patients found to have scoliosis were contacted. The incidence of back pain was 59% (similar to that in the general population). Back pain was subdivided into mild (44%), moderate (49%), or severe (7%). The curve was subdivided into three categories: 10-24°, 25-44°, and 45+°. Of the 82 idiopathic curves with pain, 64 were in group 1, 15 in group 2, and 3 in group 3. Forty-three percent had mild pain, 50% had moderate pain, and 7% had severe pain. As the degree of curvature increased, the severity of pain increased, especially for curves of more than 45°. Patients without back pain tended to have smaller curves. The presence of facet sclerosis correlated with a history of pain in 64%. There was a high correlation between radiologic changes at the curve apex and pain. Age bore no relationship to the incidence of pain.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID

摘要:

We have been using the differential spinal block to study patients referred to our Pain Clinic for treatment of their chronic pain syndromes. In a selected group of chronic-pain patients from whom cerebrospinal fluid (CSF) could not be obtained at the L4 or L5 interspace, administration of autogenous CSF obtained at a higher interspace gave immediate and complete but temporary pain relief. Endorphins were present in these autogenous CSF samples. These studies, indicating that CSF even from chronic-pain patients contains analgesic substances (possibly endorphins), may point to new treatment modalities for certain chronic back pain syndromes.

ISSN:0362-2436    

出版商:OVID    

年代:1981

数据来源: OVID