The aim of this study is to investigate the hand function in patients with poly-and dermatomyositis and compare this to healthy individuals and norm values and secondly if hand function correlates to activity performance and health related quality of life.
The study is a cross-sectional study. To assess hand function the investigators will measure grip force with Grippit and arm/hand mobility using EPM-ROM scale. The activity performance will be measured with Myositis Activities Profile and health related quality of life will be assessed with SF-36.
The investigators' hypothesis is that hand function is reduced in comparison to the healthy population and that hand function affects both activity performance and health related quality of life.