The range-of-motion of the trapeziometacarpal joint is difficult to assess clinically. The purpose of our study was to constitute a range-of-motion database from normal active trapeziometacarpal joints.Two hundred hands from 101 healthy subjects (50 female and 51 male) with a mean age of 23.1 years (range: 22 to 35 years) have been evaluated. An optoelectronic device (Polaris) was used to analyse the thumbs range-of-motion. Splints were fitted so as to isolate the trapeziometacarpal joint and retroreflective markers were placed both on the splints and on the thumb. After active flexion-extension, abduction-adduction, axial rotation and circumduction, the different range-of-motion parameters were calculated.The mean range-of-motion of the trapeziometacarpal joint was 41 degrees for flexion-extension, 51 degrees for abduction-adduction and 21 degrees for axial rotation. Comparisons between female and male subjects showed significant differences concerning flexion-extension, abduction-adduction axial rotation and circumduction. No significant differences were noted between right and left hands except for the abduction-adduction movement.One hundred and one healthy subjects were analysed for the development of a database of normal active range-of-motion parameters of the trapeziometacarpal joint, with an in vivo protocol. This database should allow comparing the range-of-motion of patients with osteoarthritic trapeziometacarpal joint and assessing surgical outcome.