Radiological anthropometry of the hand in Turner's syndrome

Metacarpal-phalangeal (M-P) lengths, metacarpal sign, and carpal angle were studied using 142 pairs of hand X-rays from 81 individuals with Turner's syndrome age 6 to 25 years. Left M-P lengths, grouped by bone age, were compared with normal female standards and Z-score pattern profiles calculated for each bone age. Differences between Turners and normals in most M-P lengths increased with age, particularly after puberty. Calculation of inter-individual and intra-individual variability yielded good evidence for a M-P pattern profile typical of Turner's syndrome, with increasing growth deficiency from distal to proximal and lateral to medial. The incidence of positive metacarpal sign was 33.8%, with no significant difference between XO and non-XO Turners. It did not appear that M4 ceased growth prematurely, suggesting that short M4 is not the result of early epiphyseal fusion. Carpal angle, reported to be abnormally decreased in Turners, was not found to differ from normal. There was no difference between right and left sides or between XO and non-XO Turners, but carpal angle did decrease significantly with both decreasing ulnar deviation in positioning of the hand and increasing age. In the latter respect Turners differ from normals who show an increase in carpal angle with age.