Monitoring bone strontium intake in osteoporotic females self-supplementing with strontium citrate with a novel in-vivo X-ray fluorescence based diagnostic tool

The mean baseline Sr signal observed for the group was 0.42 ± 0.13 and 0.39 ± 0.07 for the finger and ankle, respectively. After 24 h, the mean Sr signal rose to 1.43 ± 1.12 and 1.17 ± 0.51, for the finger and ankle, respectively, representing a statistically significant increase (p = 0.0043 & p = 0.000613). Bone Sr levels continued to increase throughout the length of the study. However the Sr signal varied widely between the individuals such that after three years, the highest Sr signal observed was 28.15 ± 0.86 for the finger and 26.47 ± 1.22 for the ankle in one volunteer compared to 3.15 ± 0.15 and 4.46 ± 0.36, for the finger and ankle, respectively in another. Furthermore, while it was previously reported by our group, that finger bone Sr levels may plateau within two years, these results suggest otherwise, indicating that bone Sr levels will continue to rise at both bone sites even after 4 years of Sr intake.