Bone Abstracts

Objectives: Turner syndrome (TS) affects 1:2000 girls and is mainly characterised by short stature and ovarian failure. Increased fracture risk has been reported in historical cohorts of women with TS and it was linked to their decreased bone mineral density (BMD). Nowadays, girls with TS are treated with growth hormone and substituted with estrogens, of which role in optimal bone mass accretion has been confirmed. Whether increased fracture rate is still of concern in these patients remains to be elucidated.

Methods: The extremity long bone and vertebral fractures were recorded from the National Registry of Hospitalised Patients and the demographic data were obtained from the National Institute of Health Information and Statistics. Fracture data were also recorded from the largest children hospital in the country to calculate the age-specific proportions of hospitalised patients. The age-specific fracture incidence in girls up to 20 years of age was calculated. Data for years 2008–2014 were averaged. Monte Carlo simulation was used to estimate the probability of certain number of fractures. The incident fractures were recorded in 32 girls with TS over 6 year observation period. All patients were treated with growth hormone and, if appropriate, substituted with estradiol.

Results: Among the 32 girls with TS, three sustained new fracture during the 6 year follow-up. The fracture rate in the healthy population increased form birth up to age 11 years with a peak incidence of 20%. Then the incidence decreased and was 2% at age 20. Based on the age-specific fracture rates in healthy population calculated from the same years as was the follow-up of girls with TS, the lower limit for the expected number of fractures was 4.4 over the six year observation period. The upper limit for the probability of observing maximum 3 new fracture cases over the six-year follow-up was 0.34.

Conclusion: Our study demonstrates that girls with TS getting currently recommended standard hormonal treatment do not present with increased fracture rates compared to those in otherwise healthy girls. We encourage similar studies in other developed countries to confirm this finding.

Disclosure: The authors declared no competing interests.