Posterior Elements (posterior + element)

Distribution by Scientific Domains


Selected Abstracts


Evaluation of the diagnostic utility of spinal magnetic resonance imaging in axial spondylarthritis

ARTHRITIS & RHEUMATISM, Issue 5 2009
A. N. Bennett
Objective Magnetic resonance imaging (MRI) is increasingly used for the diagnosis of axial spondylarthritis (SpA), but it is unknown whether characteristic lesions are actually specific for SpA. This study was undertaken to compare MRI patterns of disease in active SpA, degenerative arthritis (DA), and malignancy. Methods Fat-suppressed MRI of the axial skeleton was performed on 174 patients with back pain and 11 control subjects. Lesions detected by MRI, including Romanus lesions (RLs) and end-plate, diffuse vertebral body, posterior element, and spinous process bone marrow edema (BME) lesions, were scored in a blinded manner. An imaging diagnosis was given based on MRI findings alone, and this was compared with the gold-standard treating physician's diagnosis. Results The physician diagnosis was SpA in 64 subjects, DA in 45 subjects, malignancy in 45 subjects, other diagnoses in 20 subjects, and normal in 11 subjects. There was 72% agreement between the imaging diagnosis and physician diagnosis. End-plate edema, degenerative discs, and RLs were frequently observed in patients with any of the 3 major diagnoses. Single RLs were of low diagnostic utility for SpA, but ,3 RLs (likelihood ratio [LR] 12.4) and severe RLs (LR infinite) in younger subjects were highly diagnostic of SpA. Posterior element BME lesions of mild or moderate grade were also highly diagnostic of SpA (LR 14.5). The most common diagnostic confusion was between SpA and DA, since both had RLs present and the presence/absence of degenerative discs did not change the diagnostic assessment. Conclusion This study confirms the high diagnostic utility of MRI in axial SpA, with severe or multiple RLs evident on MRI being characteristic in younger patients and mild/moderate posterior element lesions being specific for SpA. However, MRI lesions previously considered to be characteristic of SpA could also be found frequently in patients with DA and patients with malignancy, and therefore such lesions should be interpreted with caution, particularly in older patients. [source]


Magnetic resonance imaging of cauda equina syndrome in long-standing ankylosing spondylitis

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 4 2007
A Arslanoglu
Summary The cauda equina syndrome is an uncommon complication of long-standing ankylosing spondylitis and its aetiology is controversial. We report a case of the cauda equina syndrome, erosion of the posterior elements of the lumbar spine and traction of the lumbar nerve roots because of multiple dural diverticula in a patient with long-standing ankylosing spondylitis. Magnetic resonance imaging is valuable in excluding other spinal lesions. Extensive dural diverticula formation is characteristic of ankylosing spondylitis and has the potential to provide an early diagnosis. [source]


Distinctive new form of spondyloepimetaphyseal dysplasia with severe metaphyseal changes similar to Jansen metaphyseal chondrodysplasia

JOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 1 2005
A Al Kaissi
Summary We report a boy with a unique, ,new' form of spondyloepimetaphyseal dysplasia. The conspicuous features of the spinal changes were the delay in ossification of the cervical spine and posterior elements of the thoraco-lumbar spine. The vertebral bodies were of abnormal shape but of normal size and well ossified. The hallmark of epiphyseal changes was markedly delayed ossification (bone age). The severely disturbed metaphyseal ossification was similar to Jansen metaphyseal dysplasia. This pattern of changes has not yet been described in spondyloepimetaphyseal dysplasia. [source]


Association of rudimentary sacral zygapophyseal facets and accessory and ligamentous articulations: Implications for load transmission at the L5-S1 junction

CLINICAL ANATOMY, Issue 6 2010
Niladri Kumar Mahato
Abstract Weight transmitted from the fifth lumbar vertebrae to the sacrum is distributed as three separate components between (a) the vertebral bodies anteriorly, (b) the transverse elements intermediately, and (c) the lumbosacral facet joints, posteriorly. The posterior components of the fifth lumbar vertebra share greater proportion of load in comparison with the posterior elements of the upper lumbar vertebral levels. This study focuses on rudimentary lumbosacral facet articulations and their possible effects on load sharing at this region. Twenty sacra bearing rudimentary articulations were collected for analysis. Sixteen of these sacra presented unilateral rudimentary facets, and the remaining four had facets that were bilaterally rudimentary. Thirteen of the sacra with unilateral rudimentary facets showed an accessory articulating area on the upper surface of the ala on the same side as the rudimentary zygapophyseal facet. The remaining three sacra (out of the 16) showed evidence of strong ligamentous attachments between the L5 and S1 transverse elements on the sides of the rudimentary facets. All the sacra with bilateral rudimentary facets demonstrated bilateral accessory L5,S1 articulations. These observations indicated that load transmission at lumbosacral junctions bearing a rudimentary facet joint is not normal and that their associations with strong L5,S1 lumbosacral ligamentous attachments or accessory articulations at the transverse elements serve a compensatory mechanism for load sharing. Clin. Anat. 23:707,711, 2010. © 2010 Wiley-Liss, Inc. [source]