pQCT is a method which allows the separate determination of cortical and trabecular bone mineral density in the peripheral skeleton. 21 thalassaemic patients (8 females, 13 males) aged from 10 to 32 years, were examined using pQCT at the ultra distal radius to evaluate SSI (Stress-Strain Index). ALP, serum calcium, hydroxyproline, magnesium, IGF-I, and body surface were determined. The results show a good correlation between cortical BMD and age, concentration of hydroxyproline in urine, serum bone Gla protein, body surface index, bone density of trabecular bone and SSI. Good correlation was found between trabecular bone density and age, IGF-I, BGP and PTH, and between SSI and cortical BMD, age and BSI. The linear relationships between age and cortical and trabecular density show an increase of cortical BMD with age and a decrease of trabecular density with age. The same results were obtained considering trabecular and cortical density versus SSI.