Histological and histomorphometrical measurements were made on normal and on osteoporotic bone from the first lumbar vertebra and the iliac crest of 15 cases. A decrease in cancellous bone was found in both. This was accompanied by a reduction in haematopoietic marrow and a corresponding increase in fat cells. In addition, the numbers of arterial capillaries and sinuses per unit area were also reduced. There is a greater overall vascularization in the first lumbar vertebra than in the iliac crest, even though the amount of cancellous bone is normally less in the former. However, the arborization of the terminal vessels in the iliac crest is more extensive than that in the first lumbar vertebra. These observations provide support for the participation of a vascular component in the pathogenesis of osteoporosis.

Adipose Tissue↗

PubMedDate not supplied

Controlled clinical trials and medical ethics.

During the past 5 years, a great deal of public attention has been paid in the Federal Republic of Germany to legal and ethical implications of controlled clinical trials. If a physician is bound by a contract for treatment, the ethics of individual benefit have to be applied and this might inhibit a controlled trial. To avoid ethical and legal difficulties, a contract for experimentation may have to be introduced.

Clinical Trials as Topic↗