Iliac crest biopsy: an investigation on certain aspects of precision and accuracy.

We investigated the intraobserver and section to section variation in static and dynamic histomorphometric variables in ten iliac crest biopsies. We also did a comparative study of iliac crest and lumbar spine specimens from 14 cadavers. The ten patients had osteoporosis (spinal crush fractures) and the 14 specimens taken at the necropsies were either normal or osteopenic, without malignant bone disease, bone metastases or metabolic bone disease. The majority of the coefficients of variation (CV%) were between 5 and 15% in the intraobserver analysis and 10 and 30% in the section to section analysis. These results suggest that more sections from each biopsy should be investigated to increase the precision. The correlation of variables from the iliac crest and spine showed poor agreement between resorption and osteoid variables. This fact, combined with a rather low precision of bone dynamic variables in the section to section investigation, raises the question of whether iliac crest biopsy is representative for trabecular bone turnover in the skeleton.