title: [Biomechanical aspects of surgical treatment of secondary stenosis of the spinal canal in the lumbosacral region].
abstract: In experimental studies and on clinical material, behaviour was checked of intervertebral discs and vertebrae under the axial pressure: which is the being exerted by the trunk weight, as well as the behaviour of the adjacent mobile segments after "diskoplasty" operation or vertebral interbody stiffening. The material pertaining to the experimental part comprises 6 undamaged spine preparations of the lumbosacral segment, while the clinical part consists of 60 patients out of 143 subjects having been operated on by "diskoplasty" or vertebral interbody stiffening from the approach through fenestration, hemilaminectomy, or plastic laminectomy. The results of performed experimental studies and spodylometric analysis of radiograms in patients treated operatively by decompressing the vertebral canal and by "diskoplastic" stabilization of the vertebrae, or vertebral interbody stiffening permit the following observations. The most favourable localization of the transplant is the medial and posterior parts of the vertebral interbody space, since in both segments L4/L5 and L3/L4 it reproduces the height of the vertebral interbody space, the height and width of intervertebral foramen, widens the intervertebral foraminis, and reduces the lumbar lordosis, which advantageously changes the biomechanic relations, transferring loads of the posterior to the anterior vertebral column. The localization of the transplant in the anterior part of the vertebral interbody space, in fact, increases the anterior vertebral interbody space, but decreases the height of posterior interbody space, the vertebral interbody angle alpha as well as the height and width of the intervertebral foramen. The retroshifting of vertebral L4 indicates mobile segment instability. By implementing a transplant of matching height and appropriate localization in vertebral interbody space, it is possible to increase or reduce the angle between the vertebral bodies at the operative level, widening the vertebral interbody space in anterior and posterior parts. The localization of the bony transplant in the anterior part of vertebral interbody space, involving the clinical material, caused in 65% constriction of intervertebral foraminis, retroshifting of vertebrae L4 and L3, and recurrence of algesic complaints, which may be elucidated by instability of the operated on or adjacent mobile segments.
authors.affiliation: Kliniki Ortopedii Pomorskiej Akademii Medycznej.
authors.forename: R
authors.initials: R
authors.lastname: Król
mesh_terms: D000328:Adult; D000886:Anthropometry; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D007403:Intervertebral Disc / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery*; D007405:Intervertebral Disc Displacement / Q000150:complications / Q000473:pathology / Q000601:surgery*; D007796:Laminectomy / Q000379:methods; D008159:Lumbar Vertebrae / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D008953:Models, Anatomic; D012447:Sacrum / Q000033:anatomy & histology / Q000473:pathology / Q000601:surgery*; D013123:Spinal Fusion / Q000379:methods; D013130:Spinal Stenosis / Q000209:etiology / Q000473:pathology / Q000601:surgery*
vernacular_title: Biomechaniczne aspekty operacyjnego leczenia wtórnej ciasnoty kanału kregowego w odcinku ledźwiowo-krzyzowym.