Fig. 1
![Fig. 1](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs12891-016-1348-5/MediaObjects/12891_2016_1348_Fig1_HTML.gif)
a Normal hand X-ray without signs of RA b Demineralisation of the metacarpal bone, joints space narrowing of the metacarpophalangeal joint I to V (asterix) and erosions of the metacarpophalangeal joint (arrows) c Severe demineralisation of the metacarpal bones as well as advanced joint space narrowing of the carpus and metacarpophalangeal joint I to V (asterix) with total loss of joint space at the metacarpophalangeal joint II and III, erosive destruction of the metacarpophalangeal joint III and subluxation of the metacarpophalangeal joint I