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W J Whitehouse

Publications and source records attributed to W J Whitehouse.

12 recordsLinked to original sources
PubMed1976

Errors in area measurement in thick sections, with special reference to trabecular bone.

A formula is derived for the errors caused by section thickness in the measurement of the mean cross-sectional areas of opaque material embedded in a transparent medium. There are some simplifying assumptions which can only be justified by limiting the maximum thickness of the section, but no restriction whatever is placed upon the shape of the opaque material. For isotropic materials a very simple formula is found, relating the relative error in cross-sectional area to measurements of area and boundary profile length on the section surface. The effect of anisotropy in the material may be very large. To illustrate this, numerical calculations are made for two particular classes of simple anisotropic material, those which might be made from isotropic materials by linear distortions.

Bone and Bones↗
PubMed1975

Scanning electron micrographs of cancellous bone from the human sternum.

Thick sections from the manubrium and the first and second sternabrae were polished and the marrow removed. Low magnification scanning electron micrographs show that the cancellous bone near the medial plane is lightly constructed, is not markedly anisotropic and does not vary greatly from place to place. In the lateral parts of the sternabrae the trabeculae are somewhat thicker and the spaces between them are larger. Measurements on the polished surface lead to numerical values of a number of parameters characteristic of the surface patterns, such as the relative surface occupied by bone, the mean widths of the trabecular sections, the mean path lengths through the bone or marrow, and a number representing the departure from isotropy of the pattern. Parameters characteristic of the three-dimensional trabecular structure can be deduced, viz., the relative volume of bone, the area of the interface between bone and marrow and the mean thickness of the trabeculae. The sternum is compared with other bones which have been investigated by the same methods. There is little resemblance to the rib or to the proximal femur. The cancellous bone in the sternum and in the lumbar vertebral body are similar in appearance but the former has slighter trabeculae and larger marrow spaces.

Adult↗