Radiographic scoring methods in psoriatic arthritis.

Psoriatic arthritis (PsA) leads to structural damage that can be an important driver for disability and handicap associated with the disease. Serial radiographs, usually of hands and feet, facilitate follow-up documentation of development of these changes. Semi-quantitative scoring methods are designed to measure the degree of radiographically detectable joint damage, and of changes over time. Several radiographic scoring methods that had been developed originally for rheumatoid arthritis have been adopted for the use in PsA. Four different scoring methods used in PsA are presented with instructions on how to use them: modified Steinbrocker global scoring method; PsA scoring method based on Sharp method for RA; Sharp van der Heijde modified method; and PsA Ratingen score (PARS). Available data on the reliability, sensitivity to change, and use in clinical trials, of these four methods are presented.