High definition macroradiography was used to provide an image of the detailed structural organization of the cancellous bone in human lumbar vertebrae. The fractal signature analysis (FSA) method was used to quantify the horizontal and vertical trabecular organization recorded within the image. Comparison of the FSA of the postero-anterior and lateral macroradiographs in postmortem lumbar vertebrae showed that neither the superimposition of the neural arch nor the radiographic angle affected the trabecular measurement within the vertebral body. FSA analysis of the trabecular structure measured from the macroradiographs of lumbar vertebrae in two groups of postmenopausal women, with high and low bone mineral density (BMD), showed that the large vertical trabecular structures correlated with the women's body weight (P < 0.01-0.03) and body mass index (P < 0.005-0.05), the fine horizontal structures correlated with the women's age (P < 0.005-0.05), and fine vertical trabecular structures were significantly greater (P < 0.005-0.05) in the low compared with the high BMD group.

In this prospective study, the radiological features characteristic of osteoarthritis of the hand were compared with the radionuclide bone scan images. A total of 32 patients was assessed at 6-monthly intervals for 18 months. Microfocal radiographs were taken at each visit. The high magnification and resolution of this technique permitted direct measurement of joint space width, subchondral sclerosis, osteophyte number and area and juxta-articular radiolucency area for each joint in the hand. Four-hour technetium 99m methylene diphosphonate bone scans were taken at 0 and 12 months and the activity of tracer uptake at each joint scored. The latter was compared with each X-radiographic feature at every visit and the changes between visits analysed. The scan scores did not correlate with any of the X-radiographic features other than osteophyte size. During the study the size of growing and remodelling osteophytes increased significantly at joints with raised or increased isotope uptake.

A comparison has been made between themetabolic consequences of daily administration for 6 weeks of 1.0 micrograms and 0.5 micrograms 1 alpha hydroxyvitamine D3 (1 alpha(OH)D3) in twenty patients with senile osteoporosis. There was no significant difference in the increase of calcium absorption which occurred in the two treatment groups between the beginning and end of the trial period. Serum and urinary calcium rose significantly in those receiving 1.0 micrograms 1 alpha(OH)D3 but not in the lower dosage group. Serum parathyroid hormone levels were suppressed in the higher dosage group only. There was a significantly greater rise of serum inorganic phosphate, and fall of serum magnesium, on the higher dosage, but no significant change in serum creatinine occurred in either group. It is, therefore, suggested that in long term therapy regimes for osteoporosis incorporating 1 alpha(OH)D3, 0.5 micrograms may be a more suitable daily dose than 1.0 micrograms 1 alpha(OH)D3.

Measurement of bone mineral density (BMD) with dual-energy X-ray absorptiometry (DXA) is widely used in clinical practice for the diagnosis of osteoporosis and assessment of fracture risk. However, variants and artefacts such as, osteophytes and metallic objects can affect the BMD results of the spine and hip. We demonstrate a spectrum of clinical examples that may impact on BMD evaluation. Recognition of such artefacts is important for the correct interpretation of these studies.

During the past ten years the range of treatments available for patients with osteoporosis has increased greatly. A decade ago the only proven therapy was oestrogen, while today the choice includes bisphosphonates, selective oestrogen receptor modulators, calcitonin, calcium and vitamin D supplementation and, in the near future, parathyroid hormone. Clinical trials involving bone mineral density (BMD) scans of the spine and femur have had an important role in the evaluation of these new therapies. Supplementary information about treatments has been provided by BMD scans of the total body and distal radius as well as by measurements of biochemical markers of bone turnover in serum and urine. Most important of all, the efficacy of treatments has been verified in large trials powered to show reductions in fracture risk. In routine clinical use, BMD scanning has an important role in identifying individual patients with osteoporosis and helping to make decisions about their treatment. However, in contrast to the use of BMD scans in clinical trials, their value for monitoring response to therapy in individual patients is less certain because in many cases the increases in BMD are too small to reliably distinguish between true changes and measurement error. However, experience with well established therapies such as oestrogen and bisphosphonates suggests that these treatments have a beneficial effect on bone in the large majority of patients and individual monitoring of BMD is probably not necessary.