Quantitative ultrasound in osteoporosis and bone metabolism pathologies.

Quantitative ultrasound (QUS) has been introduced in the medical field for the study of bone tissue to identify changes in the tissue that could suggest the presence of osteoporosis and bone fragility. The ultrasound technique is simple, versatile, and its low cost and lack of ionizing radiation have led to the diffusion of this method worldwide. The present article is an overview of the most relevant developments in the field of quantitative ultrasound, in clinical and experimental settings. The advantages and limitations of the present technique and suggestions for its use in the clinical practice are reported.

Cortical thickness and medullary canal dimensions of the bone phalanx are predicted by quantitative ultrasound parameters.

The aim of the study was to investigate the relationship between quantitative ultrasound (QUS) parameters extracted from the analysis of the ultrasound (US) signal and the geometric properties of the bones. One hundred and one subjects in the age range of 20-7 4yr (mean: 52+/-12 yr) have been measured by QUS at the phalanges for the evaluation of amplitude-dependent speed of sound (AD-SoS), bone transmission time (BTT), US peak amplitude (UPA), signal dynamic (SDY), slope, energy, and fast wave amplitude (FWA). Hand radiograph, lumbar spine dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT), and femoral neck DXA forearm peripheral QCT were performed on all patients. BTT is related to cortical thickness (CTh) (r=0.62, p<0.0001), and FWA is related to medullary canal thickness (r=-0.64, p<0.0001). Other parameters are related to both medullary canal thickness (AD-SoS: r=-0.21; UPA: r=-0.53; SDY: r=-0.56; slope: r=-0.64; energy: r=-0.44, p<0.05) and CTh (AD-SoS: r=0.54, p<0.0001; UPA: r=0.51; SDY: r=0.38; slope: r=0.32; energy: r=0.56, p<0.001). Linear multivariate models indicate that BTT, UPA, and energy measured at the phalanges carry independent information on CTh of the bone, whereas FWA, SDY, and slope are related only to medullary canal thickness.

Imaging of the sacroiliac joint involvement in seronegative spondylarthropathies.

Involvement of the sacroiliac joints is the first predominant finding of all seronegative spondylarthropathies (SpA) subsets, such as ankylosing spondylitis, psoriatic arthritis, and undifferentiated SpA. Although conventional radiography is indicated in the initial evaluation of sacroiliac joints diseases, it is often insensitive for demonstrating the early changes of sacroiliitis, so other imaging techniques typically are often necessary to clarify the pathology and for establishing the early diagnosis of seronegative SpA. Other imaging modalities, including computed tomography (CT), magnetic resonance imaging (MRI), ultrasonography (US), and bone scintigraphy have improved visualization of inflammatory changes at the sacroiliac joints (SIJ). CT scans are indicated for disease processes in which bony destruction or ossification may occur. MRI has been proposed as an imaging method to detect sacroiliitis earlier. MRI can identify both inflammation and structural changes caused by inflammation, while radiographs show only structural changes. MRI may be particularly useful in making a diagnosis of SpA. Musculoskeletal US has an increasing and relevant role in the evaluation of SpA mainly for its ability to assess joint and periarticular soft tissue involvement and in particular for its capacity to detect enthesitis. US assessment in general is safe, noninvasive, and comparably cheap, showing itself as a complimentary tool to clinical evaluation in SpA; nevertheless, it is very user dependent. Bone scintigraphy is at most of limited diagnostic value for the diagnosis of established AS, including the early diagnosis of probable/suspected sacroiliitis. The main aim of this study is to introduce the clinical and radiological aspects of the SIJ involvement in SpA, particularly the contribution of the different imaging techniques.

Imaging of the seronegative anterior chest wall (ACW) syndromes.

The sternocostoclavicular (SCC) region is subject to the same diseases that occur in joints, with congenital and developmental anomalies, inflammatory and infectious diseases, soft tissue and bone tumors as well as the seronegative spondyloarthropathies, including ankylosing spondylitis, reactive arthritis, enteropathic arthritis, psoriatic arthritis, pustulosis palmoplantaris and other syndromes. Most of these conditions present with swelling of the joint, which may be associated with pain and/or tenderness. These disorders are characterised by onset usually before the age of 40 years, absence of serum autoantibodies and sometimes the association with antigen human leukocyte antigen B27. Traditional X-ray study is indicated in the initial evaluation of SCC joint disorders, but other imaging modalities typically are often necessary to clarify the pathology. Computed axial tomography scans are indicated for disease processes in which bony destruction or ossification may occur. Magnetic resonance imaging provides more detailed and useful information when evaluating suspected pathology involving inflammation or soft tissue mass. Bone scintigraphy can help to correlate active inflammation of the SCC joint with symptoms of pain. The purpose of this study is to introduce the clinical and radiological aspects of the seronegative anterior chest wall diseases, particularly the contribution of the different imaging techniques.