Changes in trabecular bone structure in rickets and osteomalacia: The potential of a medico-historical collection

Abstract

In this study lumbar vertebral bodies with and without disturbed mineralization from a medico-historical collection of the 19th century (housed in the Federal Museum for Pathological Anatomy, Vienna) were investigated, using non-invasive radiological and invasive histological techniques. Macerated, or partly dissected, or fixation fluid conservated skeletal preparations from 61 individuals with known age and gender were examined. The specimens of 37 individuals had gross pathologic alterations from rickets or osteomalacia. The specimens from 24 individuals without Known bone disease served as age-matched controls. Bone structure and mineralization in all specimens were evaluated by non-invasive techniques (conventional radiographs and computed tomography). Thirteen selected specimens from both groups were also analysed by quantitative computed tomography (qCT) and dual-energy X-ray absorptiometry (DEXA). In these cases invasive techniques (light and scanning electron microscopy [backscattered electron (BSE)- and secondary electron (SE)-mode] on surface-stained and carbon-sputtered undecalcified histological ground sections) were applied. Corresponding microradiographs were also used for computer-assisted morphometry. The clinically established method of determination of bone mineral densities (BMD) by qCT and DEXA failed in these historical specimens, but all other non-invasive and invasive techniques were successfully applied and yielded results corresponding to radiological changes and histomorphometric parameters. In the rachitic vertebrae it was not volume densities (bone volume per tissue volume = BV/TV), but numbers of trabeculae (trabecular number=Tb.N.) which were increased, compared to the age-matched vertebral bodies without bone disease. In osteomalacic vertebrae the volume densities (BV/TV) were decreased in the whole vertebral body, while Tb.N. were only decreased in the middle third of the vertebral body. Accordingly, surface densities (Sv) in non-adults, and also specific surfaces (S/V) in adults were increased, suggesting increased bone resorption. Depending on the preparation technique used in the present study, resorption lacunae and characteristic unmineralized osteoid seams could be demonstrated. In conclusion, it might be useful to establish such techniques and standards for the diagnosis of disturbed mineralization in clinical patients. Copyright © 2003 John Wiley & Sons, Ltd.