Normative data for ultrasound measurement of the calcaneus within different female ethnic groups

The purpose of this study was to generate normative broadband ultrasound attenuation data for UK resident Indian-Asian, African-Caribbean and Chinese women, aged 20-80 years, using the McCue Cubaclinical II device. Additionally, comparisons were made against available Caucasian data previously collected by the authors. Exclusions were: use of hormone replacement therapy, corticosteroids or thyroxine for more than 6 months; menopause before the age of 45 years; oophrectomy; lactation within the preceding year; rheumatoid arthritis or a previous osteoporotic fracture. 977 women were recruited from various community centres, from a local GP surgery and from university colleges in the London area. Broadband ultrasound attenuation and velocity of sound were determined for the left and right os calces. Repeat measures on each side after re-positioning, to allow for anatomical variation, were averaged. Significance was set at a minimum level of 0.05. There were significant differences in non-dominant and dominant measures in all ethnic groups except African-Caribbean. For comparison purposes the means of the non-dominant measurements were plotted against age using a polynomial model to give the best data fit. No significant difference was found between non-dominant broadband ultrasound attenuation measurements for either Asian or Chinese when compared with the Caucasian sample populations. A significant difference in broadband ultrasound attenuation was found between African-Caribbean and Caucasian, with African-Caribbean between 10% (age group 20-30 years) and 29% (age group 70-80 years) higher. There was no significant difference in body mass index between Caucasian and Chinese groups, but significant differences were found between Caucasian and Asian, and between Caucasian and African-Caribbean groups.