On MRI, abnormal signals of the intervertebral disc, destruction of the upper and lower vertebral body endplate around the disc, and bone marrow edema around the endplate are considered typical findings of infectious spondylitis. These findings can also appear in various non-infectious spinal diseases, such as degenerative changes, acute Schmorl’s node, spondyloarthropathy, synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO), chronic recurrent multifocal osteomyelitis, and calcium pyrophosphate dihydrate crystal deposition disease. The imaging findings of infectious spondylitis that can be differentiated from these non-infectious spinal diseases on MRI are high signal intensity and abscess of the disc space, an abscess in the paraspinal soft tissue, and the loss of the linear low signal intensity on T1-weighted images of the bony endplate. However, these differentiation points do not always apply since there are many similarities in the imaging findings of infectious and non-infectious diseases. Therefore, for an accurate diagnosis, it is important to know the imaging characteristics related to the pathophysiology of not only infectious spondylitis but also non-infectious spinal diseases, which requires differentiation from infection.

Objective: The aim of this study was to compare the diagnostic performances of digital tomosynthesis (DTS) and conventional radiography in detecting osteonecrosis of the femoral head (ONFH) using computed tomography (CT), as the reference standard and evaluate the diagnostic reproducibility of DTS. Materials and Methods: Forty-five patients (24 male and 21 female; age range, 25–77 years) with clinically suspected ONFH underwent anteroposterior radiography, DTS, and CT. Two musculoskeletal radiologists independently evaluated the presence and type of ONFH. The diagnostic performance of radiography and DTS in detecting the presence of ONFH and determining the types of ONFH were evaluated. The interobserver and intraobserver reliabilities of each imaging modality were analyzed using Cohen’s kappa. Results: DTS had higher sensitivity (89.4%–100% vs. 74.5%–76.6%) and specificity (97.3%–100% vs. 78.4%–83.8%) for ONFH detection than radiography. DTS showed higher performance than radiography in identifying the subtypes of ONFH with statistical significance in one reader (type 1, 100% vs. 30.8%, p = 0.004; type II, 97.1% vs. 73.5%, p = 0.008). The interobserver agreement was excellent for DTS and moderate for radiography (kappa of 0.86 vs. 0.57, respectively). The intraobserver agreement for DTS was higher than that of radiography (kappa of 0.96 vs. 0.69, respectively). Conclusion DTS showed higher diagnostic performance and reproducibility than radiography in detecting ONFH. DTS may be used as a first-line diagnostic modality instead of radiography for patients suspected of having ONFH.

Purpose: To determine the frequency of ossification of the transverse ligament of the atlas (OTLA) and to investigate the associated findings on cervical spine CT and plain radiography. Materials and Methods: We reviewed 5201 CT scans of the cervical spine of 3975 consecutive patients over an 11-year period for the presence of OTLA and compared them with those of ageand sex-matched controls. The frequency and associated findings of OTLA were investigated and statistically correlated. Results: The overall frequency of OTLA was 1.1% (45 of 3975 patients) and increased with age (p < 0.005). The frequency of OTLA in patients over 80 years was 12%. The space available for the spinal cord (SAC) was smaller in patients with OTLA (p < 0.005). Mineralization of the complex of the anterior atlantooccipital membrane and Barkow ligament, ossification of the ligamentum flavum, and kyphosis of the cervical spine positively correlated to the presence of OTLA (p < 0.005). Conclusion OTLA was associated with age, SAC narrowing, cervical kyphosis, and ossification of other cervical ligaments and may be associated with degenerative spondylosis, systemic hyperostotic status, or mechanical stress or instability.

The major purpose of this study is to construct a retrospective exposure assessment for benzene through a review of literature on Korea. Airborne benzene measurements reported in 34 articles were reviewed. A total of 15,729 individual measurements were compiled. Weighted arithmetic means [AM(w)] and their variance calculated across studies were summarized according to 5-year period intervals (prior to the 1970s through the 2010s) and industry type. Industries were classified according to Korea Standard Industrial Classification (KSIC) using information provided in the literature. We estimated quantitative retrospective exposure to benzene for each cell in the matrix through a combination of time and KSIC. Analysis of the AM(w) indicated reductions in exposure levels over time, regardless of industry, with mean levels prior to the 1980e1984 period of 50.4 ppm (n = 2,289), which dropped to 2.8 ppm (n = 305) in the 1990e1994 period, and to 0.1 ppm (n = 294) in the 1995e1999 period. There has been no improvement since the 2000s, when the AM(w) of 4.3 ppm (n = 6,211) for the 2005e2009 period and 4.5 ppm (n = 3,358) for the 2010e2013 period were estimated. A comparison by industry found no consistent patterns in the measurement results. Our estimated benzene measurements can be used to determine not only the possibility of retrospective exposure to benzene, but also to estimate the level of quantitative or semiquantitative retrospective exposure to benzene.
Benzene* ; Classification ; Korea* ; Retrospective Studies

The aim of the present study was to identify the influence of vertebral fracture (VF) on the functional disability in patients with rheumatoid arthritis (RA). This study consecutively enrolled 100 female patients aged 50 yr or older with RA. All participants underwent lateral imaging of the thoracolumbar spine by simple radiography to identify any VFs. They also completed questionnaires via interview regarding demographics, medical history, and disease outcomes including functional disability. We used univariate analysis to evaluate associations between functional disability and VF, and made multivariate logistic regression models to test independent effect of the presence of VF, the number of VFs, and the severity of VF on functional disability. Among the 100 RA patients, 47 had at least one VF, but 34 of them were asymptomatic that they had experienced a fracture. The multiple VFs > or = 3 (OR, 8.95; 95% CI, 1.77-44.15, P = 0.01) and moderate or severe VF (OR, 3.38; 95% CI, 1.26-9.04, P = 0.02) were related to disability in univariate analysis. The multiple VFs > or = 3 (OR, 6.13; 95% CI, 1.02-36.94, P = 0.048) was associated with functional disability of RA patients after adjusting various confounders and it was mainly in walking and arising. The VF might be an important factor which affects functional disability in RA patients.
Aged ; Arthritis, Rheumatoid/complications/*diagnosis ; Demography ; *Disability Evaluation ; Female ; Humans ; Interviews as Topic ; Logistic Models ; Middle Aged ; Odds Ratio ; Questionnaires ; Spinal Fractures/complications/*diagnosis/radiography