Nail disease in psoriatic arthritis: distal phalangeal bone edema detected by magnetic resonance imaging predicts development of onycholysis and hyperkeratosis.

OBJECTIVE

To examine the association between magnetic resonance imaging (MRI) features of distal phalanx (DP) disease and the progression of nail pathology in psoriatic arthritis (PsA).

METHODS

Clinical nail assessment and hand MRI scans were done on 34 patients with PsA. Twenty patients had repeat nail assessments after 1 year.

RESULTS

Nails with onycholysis and hyperkeratosis at baseline were more likely to have corresponding DP bone erosion and proliferation on MRI. DP bone edema on baseline MRI was associated with development of onycholysis and hyperkeratosis in corresponding nails.

CONCLUSIONS

Our data suggest that DP inflammation is central in the development of psoriatic nail disease.