Search

Three cases of spondylodiscitis caused by viridans streptococci were observed within the course of 1 month. Although streptococci have been reported as the third most frequent cause of spondylodiscitis after staphylococci and gram-negative bacteria, alpha-haemolytic streptococci are rarely seen. The three patients presented with symptoms of low back pain; they felt well and did not have a fever or chills. Laboratory examinations revealed inflammation. Further examinations such as scintigraphy, computed tomography or magnetic resonance imaging were done. Bacteriological diagnosis was established by blood cultures in two cases and by needle biopsy of the disco-vertebral space in one. In one patient endocarditis was also documented. Because the prevalence of endocarditis was found to be higher in our cases of spondylodiscitis due to Streptococcus viridans than for other bacteria, the exclusion of this diagnosis must be pursued aggressively. These observations lead us to question if the spectrum of bacteria causing spondylodiscitis is undergoing a change. an aetiological agent could be isolated in 1168 patients (85.4%): in 48% a staphylococcus, in 28% a gram-negative bacterium and in only 10% a streptococcus. There were two cases of viridans streptococci (0.2%). These two cases together with other single case reports [14-22] account for 15 cases of spondylodiscitis due to alpha-haemolytic streptococci. Differentiation of the organisms to the species level was accomplished in six cases: S. mitis (3), S. sanguis (2) and S. anginosus (1). Although a multitude of organisms, bacterial as well as fungal, causing spondylodiscitis has been reported in recent years, almost all were single cases [23-42]. The unusual observation of three cases of spondylodiscitis due to alpha-haemolytic streptococci within 1 month prompted us to review the clinical and laboratory findings and to compare these cases with those caused by Staphylococcus aureus.

Type X collagen has so far not been reported to occur in human intervertebral discs. The objective of this study was therefore to investigate the occurrence of type X collagen in human lumbar intervertebral discs during ageing and degeneration. Ninety intervertebral discs with adjacent endplates were excised in toto from individuals (0-86 years) without known spinal disease and were processed for routine decalcified histology. Appropriate slices of each disc were processed for immunohistochemistry using a type-specific, monoclonal antibody raised against human type X collagen. Each intervertebral disc was examined for macroscopic and histomorphological features of disc degeneration. Immunohistochemically, a positive specific type X staining was observed in the hypertrophic zone of the growth plate and only in the interstitial matrix of juvenile (2 years) nucleus pulposus. In adult discs, type X collagen could be localized in conjunction with advanced disc degeneration and first occurred in the disc matrix (i.e., pericellular region) of a 47-year-old specimen. Positive type X staining of the disc matrix was more frequently found in senile (70 years) discs with end stages of disc degeneration. This study provides the first evidence for the occurrence of type X collagen in human lumbar intervertebral discs and it appears that type X collagen is re-expressed in late stages of disc degeneration.

A 40-band integrated static gain-flattening filter (GFF) is presented. The design of the filter was optimized using a newly developed analytical model, which shows a good agreement with the experimental results. The filter has a low insertion loss of 4.1 dB, an attenuation range that exceeds 20 dB, and is able to generate slopes above 20 dB/nm. It is a first step toward an integrated high-resolution dynamic GFF.

We report on a case of chondromyxoid fibroma involving two adjacent thoracic vertebrae with features of aggressive behaviour on radiographs, CT and MRI. Histology revealed typical chondromyxoid fibroma with unusually coarse calcifications. Chondromyxoid fibroma of the spine is rare, and only 30 of these tumours have been reported so far. Involvement of two contiguous vertebral bodies by chondromyxoid fibroma, as reported here, appears exceptional.

This review provides methodological background and some guidelines for the evaluation of imaging modalities for the lumbar spine and reviews the current literature on the basis of different levels of efficacy which consider standards beyond technical quality or diagnostic accuracy. From a MEDLINE search, 672 articles (1985-1995) were retrieved which focused on the development or application of imaging modalities for lumbar spinal disorders. The papers were categorized according to different efficacy levels at which the imaging modalities were assessed. This review has demonstrated that the vast majority of reports evaluate imaging studies for the lumbar spine only at the technical efficacy level. A minor proportion of the articles focus on the evaluation at the level of diagnostic accuracy. Articles which assess imaging studies on a higher level of efficacy (e.g., diagnostic and therapeutic impact, patient outcome and cost-benefit analysis) are sparse. This review has outlined frequent methodological flaws in patient selection and design of imaging studies for the lumbar spine. The spine specialist should therefore become very critical in the interpretation of those studies and pay attention to patient selection and spectrum, choice of the reference standard, sample size, various forms of biases, and the reasoning behind clinical recommendations in order to improve his patient care.