Cortical bone mass by the BoneXpert method in children and adolescents with Klinefelter syndrome

Objectives Patients with Klinefelter syndrome (KS) are already from childhood at risk for osteopenia and fractures and present with an increased digit 2/digit 4 ratio, a marker of lower fetal testosterone exposure. We analyzed whether KS patients with a higher radiographically determined digit 2/digit 4 ratio might be at risk for a lower cortical bone accumulation, as assessed by the bone health index (BHI) by the BoneXpert method at the 3 middle middle carpals of the left hand. Methods The results of a left hand and wrist X-ray Gruelich and Pyle bone age (BA) and Bone health index (BHI) analysis by the BoneXpert ( Visiana, Holte (Denmark) analysis ( software version 2) in a cohort of 50 KS boys and adolescents were reviewed. The length of digit 2 (D2) and digit 4 (D4) were measured using computer-based calipers on same the X-ray. Standard anthropometrics at the moment of the radiological evaluation were collected. D2/D4 ratio (DR) was calculated. BA, BHI and DR results were expressed as standard deviation scores (SDS). Differences were analyzed by the Student t test and correlations by Pearson correlation analysis. Results Median (range) of age of the studied subjects was 13.1 (3.7-18.7 ) years; median DR was 0.93 (0.88-0.97) height SDS 0.53 (-1.63-3.04) and weight SDS 0.61 (-2.05-3.18). Mean (SD) BA SDS was 0.07 (1.14). BA SDS correlated significantly (p