Abstract.
The objective of this study was to determine the reproducibility of ultrasonic bone properties with a system for measuring calcanei ex situ; the influence of changes of the measurement site; and the effects of fixation, storage, and maceration. We examined 14 fixed calcanei and 12 fresh bones. Ultrasonic measurements were performed ex situ after degassing, using an Achilles+ system and a special positioning device. The instrument precision was 0.16% for speed of sound (SOS), 1.4% for broadband ultrasonic attenuation (BUA), and 1.8% for the stiffness index (SI). The short-term precision was 0.54%, 1.9%, and 2.8%, respectively. A defined shift of the measurement site (5 mm distal of the middle) led to unpredictable changes in ultrasound (US) properties (r = 0.65 for SOS, 0.82 for BUA, and 0.75 for SI). Embalment with 4% formalin/96% alcohol caused a systematic decrease in SOS, an increase in BUA, and a decrease in SI (mean =−12.7 units; P < 0.001), the effect increasing with time. However, values at 6 months of fixation and later were highly correlated with those in fresh specimens (r = 0.95 for the SI). Two weeks storage in degassed and normal solution had only modest effects on ultrasound properties. Maceration did not lead to a systematic increase or decrease of ultrasound variables, but introduced unpredictable changes (r = 0.64–0.94). We conclude that in comparative biomechanical studies it is feasible to measure calcaneal specimens embalmed in formalin/alcohol ex situ, if the primary interest is not in the absolute values but in the correlation with mechanical failure loads at other skeletal sites.
Similar content being viewed by others
Author information
Authors and Affiliations
Additional information
Received: 27 August 1998 / Accepted: 12 March 1999
Rights and permissions
About this article
Cite this article
Pöpperl, G., Lochmüller, EM., Becker, HJ. et al. Determination of Calcaneal Ultrasound Properties Ex Situ: Reproducibility, Effects of Storage, Formalin Fixation, Maceration, and Changes in Anatomic Measurement Site. Calcif Tissue Int 65, 192–197 (1999). https://doi.org/10.1007/s002239900681
Issue Date:
DOI: https://doi.org/10.1007/s002239900681