Corticomedular Index of the Right Tibia in the Diagnosis of Osteopenia in Prehistoric Skeletal Remains

Abstract

This study examined the diagnostic accuracy of the corticomedular index obtained at the midpoint of the shaft of right tibia as an indicator of osteopenia in a prehistoric sample composed of 133 individuals. Osteopenia was assessed by a histomorphometrical measure of trabecular bone volume (TBV) in an undecalcified bone section of a small part of the proximal epiphysis to: Mild, moderate, and severe osteopenia were defined as TBV values less than 17.5%, 15%, and 12.5%, respectively. The corticomedular index (CI) was determined on X-ray films of the tibiae. Mean TBV of the sample was 17.93 ± 4.97%, it was moderately correlated with CI (r = 0.43, p < 0.0001). CI values under 0.20 showed high specificity in the diagnosis of all degrees of osteopenia, whereas CI values under 0.275 showed relatively high sensitivity (90.4%) in the diagnosis of severe osteopenia. These methods were then prospectively applied in a further sample of 41 right tibiae also from a prehistoric sample of Gran Canaria. The results were similar to those in the larger sample. Thus, CI may be a useful tool in detecting osteopenia in earlier populations. Am. J. Hum. Biol. 10:37-44, 1998