Fig. 1.

TW3 stages of the distal and proximal phalangeal epiphyses of the thumb (Thumb DP and Thumb PP) in relation to the different TOCI stages. According to the TW3 system, stage E (uncovered) = width of the epiphysis not wider than that of the metaphysis, stage F (covered) = width of the epiphysis wider than that of the metaphysis but without capping, stage G (capping) = spread of the lower border of the epiphysis around the metaphysis, stage H (partial fusion) = partial fusion of the epiphysis with the presence of both whitish and dark bands on the physis, and stage I (fusion) = completed fusion of the epiphysis with elimination of the dark bands on the physis. The subsection enclosed within the dotted lines and marked by the asterisk represents expansion (refinement) of the TW3 staging system with use of the TOCI staging system.