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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Calcified tissue international 52 (1993), S. 244-247 
    ISSN: 1432-0827
    Keywords: Bone density ; Material damping ; Aging ; Osteoporosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary The aim of this work was a preliminary assessment of the feasibility of using in vivo measurements of mechanical properties of bones to detect mineral loss and further to relate them to the tendency of the bone to fracture in the case of loss of minerals, such as in osteoporosis. Previous studies of bone strength in vitro have demonstrated that the decrease in bone strength in both the spine and the femur has strong correlation with the mineral content (BMC) measured with bone densitometry. It was demonstrated that loss of mineral in the bone is accompanied by substantial change of the main mechanical properties, decrease of the Young's modulus, and increase of the damping factor. The change in those properties is one order of magnitude greater than the change in bone density. Moreover, increase of bone density, by was of training, resulted in decrease of the damping factor that also was substantially greater than the change in density. The tests showed clearly that the change in mechanical properties was much greater than the change in bone mass density. This offers an attractive new alternative to the detection of bone mass loss as it appears that the change of the bone mass is well correlated to the change in these mechanical properties. In particular, the change in the damping factor of the material was found to be much more substantial than the bone density change. Therefore, the damping mechanism offers the vehicle for a direct assessment of the bone tendency to fracture due to the loss of mass, as tendency to fracture and mass loss are known to be related. Increasing bone density due to training showed similar results. The decrease in damping, though still much greater than the increase in density, is not as much different as in the case of loss of mass because there is a point when density increases to the extent that the bone becomes compact (no voids) and its damping would not drop further with increasing mass. This method, as compared with the bone density measurement methods, appears to have some definite advantages for monitoring the mineral loss in bones.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Hypogonadism ; Bone formation ; Testosterone
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Osteoporosis has been reported to complicate androgen deficiency in males. Accordingly, we have evaluated an osteoporotic hypogonadal male with bone histomorphometry before and after 6 months of testosterone replacement. Androgen therapy resulted in increases in relative osteoid volum, total osteoid surface, linear extent of bone formation, and bone mineralization. The dramatic histological response to hormonal replacement confirms the importance of androgens in bone modeling and remodeling.
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  • 3
    ISSN: 1432-0827
    Keywords: Osteoporosis ; Calcitonin ; Coherence therapy ; Phosphate
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary Coherence therapy, popularly known by the actonym ADFR (Activate, Depress, Free, Repeat), was designed to increase bone mass in osteopenic patients. Accordingly, we report a case of a hypogonadal male with histologically proven low bone turnover osteoporosis and a progressive vertebral fracture syndrome, who responded favorably to ADFR treatment with the use of salmon calcitonin and inorganic phosphate. Dramatic increments in bone mass were observed during a 68-month period of therapy. Serial quantitative computerized tomography demonstrated a 146% increase from baseline in bone mineral density for the first 30 months of treatment, and dual energy radiography yielded a 36.5% increase for the subsequent 31–68 months. Furthermore, no episode of fracture occurred since coherence therapy was initiated.
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  • 4
    ISSN: 1432-0827
    Keywords: Bone resonant frequency ; Osteoporosis ; Osteomalacia
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine , Physics
    Notes: Summary A new computerized apparatus was constructed to measure the resonant frequency of human ulnain vivo with high sensitivity and reproducibility. Experimental studies using aluminum bar and dried human bone revealed the importance of the ulna being positioned parallel to the radius, approximately 90 degree flexion of the elbow joint, and minimal muscle activity in order to demonstrate maximum resonant frequency of ulna. Measurement of bone resonance in monkeysin vivo and after removal of the bonein vitro showed good agreement. Product of F (maximum resonant frequency in Hz) and L (ulnar length in cm), FL, indicating the speed of propagation of sound wave through the ulna, showed a significant positive correlation with bone mineral content/bone width (BM/BW) measured by Norland-Cameron apparatus and age-bound decline in both sexes. Patients with osteomalacia and primary hyperparathyroid bone disease tended to have higher FL values than expected from BM/BW. Two-dimensional display of FL and BM/BW thus appears to be useful in distinguishing osteoporosis from osteomalacia better than the use of BM/BW alone.
    Type of Medium: Electronic Resource
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