Diseases of Bone

Morphometric methods are commonly used in the diagnosis of diseases of bone. These may be divided into static and dynamic measurements. Static measurements include: (i) the proportion of trabecular surface which is resting, resorbing or covered by osteoid (by a perimeter intersect technique); (ii) the thickness of osteoid seams; and (iii) the proportion of the section occupied by mineralized bone, osteoid, woven bone, lamellar bone or fibrous tissue (by a point-counting technique or by computerized image analysis). Dynamic studies may be performed using a tetracycline labelling method. When a single dose of tetracycline is administered, it becomes incorporated at the mineralization front; this can be visualized as a single line in undecalcified sections examined under ultraviolet light. By giving two doses of tetracycline at a known interval and measuring the distance between the two lines of incorporation, it is possible to measure the mean rate of mineralization.