Joints affected from the outside-in, MRI study suggests

Tendosynovitis may be the first inflammatory process

Tenosynovitis and synovitis are the first signs of inflammation in a joint  affected by rheumatoid arthritis (RA), with osteitis and erosion coming later, according to an MRI study.

The study of 31 people presenting at a Dutch rheumatology clinic with clinically suspect arthralgia who went on to develop RA, is the largest longitudinal MRI study done to date to track the development of early disease, the authors say.

The aim was to help decide between two competing theories for how inflammation affects a joint in RA – from ‘the outside–in’ or from the inside