label: Abnormality of the epiphysis of the 1st metacarpal
label_lc: abnormality of the epiphysis of the 1st metacarpal
description: "In contrast to the metacarpals 2-5, the first metacarpal is embryologically of phalangeal origin and as such equivalent to the proximal phalanges of the digits 2-5 (whereas the proximal phalanx of the thumb is equivalent to the middle phalanges of the other digits). The epiphysis of the first metacarpal is localized at the proximal end (as seen in the proximal phalanges of the other digits), whereas the epiphyses of the other metacarpal bones are located at the distal end. This term applies if the epiphysis of the 1st metacarpal is in any way abnormal, referring to age and gender depending norms, as seen on x-rays."