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The measurement and analysis of residual stresses has gained significant importance over the past couple of years due to the increasing demands in improving the properties of new engineering materials and components. The ability to measure these residual stresses accurately will thus lead to the manufacture of stronger, lighter, and cheaper components by industry. The drive to optimize material performance whilst minimizing component weight will ensure that this field continues to grow. Experimentally, non-destructive analysis of phase-specific residual stresses is only possible by means of diffraction methods. While X-ray scattering is essentially a surface method, the high penetration depth of neutrons into the bulk material (e.g., 20 mm into steel or 100 mm into aluminium) allows extracting reliable information from the inside of components. [ABSTRACT FROM AUTHOR]

An intravertebral vacuum phenomenon was observed within 19 vertebrae of 17 patients. It represents a non-healing vertebral fracture. Three possible pathologic mechanisms are discussed: ischemic bone necrosis, trauma with ensuing ischemic necrosis, and intraosseous disc prolapse. The intravertebral vacuum phenomenon was found in two patients with multiple myeloma and thus does not exclude the presence of malignancy in the affected bone. Radiographs obtained during traction or extension may be of diagnostic value. [ABSTRACT FROM AUTHOR]

For the diagnosis of primary osteoporosis, various semiquantitative radiologic methods were compared in 149 unselected patients, aged over 50 years. Crush fracture syndrome (CFS), lumbar spine index (LSI), and Singh Index (SI) were assessed by three radiologists and after reevaluation, the intra- and interobserver errors were calculated. The reliability of the subjective grading was improved by joint and repeated reading of the radiographs. Additionally, the peripheral trabecular bone content was measured by photonabsorptiondensitometry (PAD). To test the value of the various semiquantitative methods, LSI, SI, and PAD have been compared with sex-matching before and after separation into age in decades in CFS-positive and CFS-negative patients. In an attempt to differentiate osteoporotics and non-osteoporotics by CFS, our results indicate that CFS-positive and CFS-negative males cannot be separated by LSI, SI, and PAD, whereas in females these methods can discriminate irrespective of the age in decades. However, in age related groups, only SI can discriminate significantly between CFS-positive and CFS-negative females. Correlation of the semiquantitative methods, regardless of the diagnosis of a CFS, revealed a significant correlation-between SI and PAD, but no correlation between LSI and SI, and LSI and PAD, respectively. [ABSTRACT FROM AUTHOR]

Magnetic resonance imaging (MRI) has emerged as complementary imaging modality to conventional radiography. The same diagnostic rules that are used in the interpretation of the routine radiographs should be applied to the analysis of MR images with the macroscopic spread of the disease as a main diagnostic clue. MRI has been shown to be a sensitive tool in detecting early arthritic changes and erosions, inflammation in periarticular tendons and tendon sheaths, and in juxtaarticular bursae. MRI plays a pivotal role in diagnosis of arthritis of the craniocervical junction and its complications. It also has been used effectively to detect insufficiency fractures and osteonecrosis. MRI may be important in diagnosing early arthritis, in specifying the differential diagnosis of rheumatic disease, and in selecting subgroups of patients to provide tailored therapeutic regimens [ABSTRACT FROM PUBLISHER]