Forearm bone density, cross-sectional size and muscle cross-sectional area in adolescents with diabetes mellitus type 1 assessed by peripheral quantitative computed tomography.

OBJECTIVES

The mechanical components of bone strength (size, shape and density) in adolescents with T1DM are not extensively studied.

METHODS

The studied group comprises 39 adolescents, aged 11,9-18,0 yrs. The bone and muscle properties were investigated at the forearm (66% and 4% site). All measurements were performed using pQCT method.

RESULTS

The mean Z-score calculated for the ratio of the total cortical bone cross-sectional area to muscle cross-sectional area at 66% was lower than zero in girls (-0,93+/-1,06; p=0,0042). Significant differences between Tanner stages were noted in boys for mean Z-scores for bone masses, cross-sectional dimensions and strength.

CONCLUSIONS

T1DM girls revealed a decreased ratio of cortical bone area/muscle area, reflecting disturbed adaptation of the cortical shaft to the muscle force. When the Z-scores of cortical shell dimensions were investigated, cases in Tanner stage 5 diverged from "less mature" individuals, which may suggests that bone shaft development in these individuals was impaired, affecting both size and strength.