Detailled Information

van der Heijde D, Sharp J, Wassenberg S, Gladman DD. Psoriatic arthritis imaging: a review of scoring methods. Ann Rheum Dis. 2005;64 Suppl 2:ii61–64

Assessing structural damage progression in psoriatic arthritis and its role as an outcome in research

Feasibility, reliability, and sensitivity to change of four radiographic scoring methods in patients with psoriatic arthritis

Measurement properties of radiographic outcome measures in Psoriatic Arthritis: A systematic review from the GRAPPA-OMERACT initiative

The Sharp-van der Heijde score modified for PsA is a detailed scoring method evaluating erosions, joint space narrowing, (sub)luxation, and ankylosis based on the Sharp–van der Heijde method for assessing erosions and joint space narrowing of joints of hands and feet in RA. In addition to the joints evaluated for RA, the distal interphalangeal (DIPs) of the hands are assessed.

The following joints of the hands are scored for erosions: ten DIPs/Interphalangeal Joint (IPs), ten metacarpophalangeal joints (MCPs), two first metacarpal bones, two radius and ulnar bones, two multangular units (trapezium and trapezoid combined); in the feet, ten metatarsophalangeal joints (MTPs) and two IPs of the big toes are scored.

Joint space narrowing, (sub)luxation, and ankylosis are assessed in the hands in ten DIPs/IPs, ten MCPs, two third, fourth, and fifth carpometacarpal joints, two multangular-navicular joints, two capitate-navicular-lunate joints, two radiocarpal joints, and in the feet in ten MTPs and two IPs of the big toes.

Gross osteolysis, and pencil in cup phenomena are scored and reported separately.

Scores for erosion range from 0 defined as no erosion and 3 defined as a large erosion passing the midline of the joint. If there is > 1 erosion per joint, scores can be combined to give a maximum score of 5 per joint in the hands and 10 per joint in the feet (a maximum of 5 at each side of the joint). Joint space narrowing scores vary from 0 to 4 in both the hands and feet, with 0 being normal and 4 being the absence of joint space with evident ankylosis or subluxation.

A detailed scoring for erosions comes below:

• 0 = no erosions

• 1 = discrete erosion

• 2 = large erosion not passing the mid-line

• 3 = large erosion passing the mid-line.

Joint space narrowing score is based on the following features:

• 0 = normal

• 1 = asymmetrical or minimal narrowing up to a maximum of 25%

• 2 = definite narrowing with loss of up to 50% of the normal space

• 3 = definite narrowing with loss of 50–99% of the normal space or subluxation

• 4 = absence of a joint space, presumptive evidence of ankylosis, or complete luxation.

Gross osteolysis and pencil-in-cup change are scored separately and, if present, are assigned the maximum score for erosion and joint space narrowing for the same affected joint.

The utility of radiographic assessment of structural damage as an outcome in PsA is illustrated by several clinical trials of biologic agents used to treat PsA; on some of them, the PsA-SvdH scoring system have been used, showing that it was appropriate for use in PsA.

When compared to the modified Steinbrocker scoring method, the modified Sharp score, and the PARS, the SvdH method was the most reliable and sensitive to change but required a longer time to perform. Tillet and colleagues (Arthritis Care Res. 2014) concluded that the SvdH scoring method for PsA was the best tool for use in randomized controlled trials.