Capillaroscopic findings in erosive and nodal osteoarthritis of the hands.

Osteoarthritis of the hands is a very common disease that can present a large number of different clinic pictures, such as nodal (NOA) and erosive (EOA) forms. EOA in particular is a rare subset of hand osteoarthritis characterised by faster destructive changes involving the distal interphalangeal (DIP) and proximal interphalangeal (PIP) joints. In the early stages of the disease the differential diagnosis from other arthritides, such as rheumatoid or seronegative arthritis, may pose a challenge. Nailfold capillaroscopy is a non-invasive technique that allows the in vivo study of the microvascular environment. In this study the authors have compared the capillaroscopic microvascular patterns in 56 patients with EOA, in 46 patients with NOA, and in 50 normal controls. The abnormalities that could be found in EOA patients were similar to those described by some authors in patients with psoriatic arthritis. The authors discuss the significance of these abnormalities and the possible relationship between EOA and psoriatic arthritis.