Many of you have probably read that
the only way to measure the amount of strontium in bone is to do a bone biopsy.
That is no longer true, at least not in a research setting. A case study
published last year in Bone used an in vivo X-ray
fluorescence (IVXRF) I-125 based system to measure bone strontium levels
non-invasively in an osteoporotic female volunteer before and after she began
taking strontium citrate supplements (680 mg Sr/day).
Thirty-minute
measurements were taken at the finger and ankle bone sites, representing
primarily cortical and trabecular bone, respectively. Baseline natural strontium levels were obtained followed by a 24h measurement of first
intake of strontium citrate supplements (680 mg Sr/day). The baseline levels of
strontium (prior to supplementation) were 0.38 ± 0.05 and 0.39 ± 0.10 for the
finger and ankle, respectively. After 24 hrs the levels were 0.62 ± 0.14 and
0.45 ± 0.12 for the finger and ankle, respectively. By 120 h, the increase was
statistically significant at 0.68 ± 0.07 and 0.93 ± 0.05, respectively. Further
increases occurred within an interval of 90-180 days, with the most recent,
after 800 days, at the finger and ankle being 7 and 15 times higher than the
initial baseline reading. The results show bone strontium incorporation and retention follow a pattern and suggest strontium levels, at least in the ankle, do not plateau within two to three years and will continue to increase over time, as an individual takes strontium supplements. The ability of this IVXRF system to monitor and measure bone strontium levels over time provides a useful diagnostic tool to help gain insight into strontium bone kinetics.
