Definitions for PAM proposed in the literature.
| Study | Definition | Citation Index |
|---|---|---|
| Moll and Wright2 | Digital telescoping (doigt en lorgnette) or opera glass finger resulting from severe osteolysis. | 768 |
| McGonagle, et al19 | Diffuse bone destruction of the small joints of hands, especially the DIP joints, with bone changes that are reminiscent of enthesopathy-associated bone lesions. | 169 |
| Helliwell, et al17 | Severe destructive changes in small joints of hands and feet with telescoping of at least 1 digit. | 132 |
| Marsal, et al18 | Complete erosion of the metacarpal or metatarsal head and the corresponding epiphysis of the phalanx or both epiphyses of an interphalangeal joint of a finger or a toe. | 75 |
| Tan, et al20 | Pencil-in-cup deformities or bone lysis causing 30–50% resorption of proximal and middle phalanges manifesting clinically as digital shortening or radiographically as complete erosion of bone at both sides of the joints. | 11 |
| Helliwell21 | Patients with PAM are more likely to have polyarticular, symmetrical disease for a long duration and positive CCP in the context of bone osteolysis, ankylosis, entheseal abnormalities, and spinal abnormalities. | 4 |
| Gudbjornsson, et al22 | Presence of clinical arthritis of type PAM that is also radiographically confirmed. | 1 |
| Chandran, et al74 | ≥ 5 joints with grade IV damage using the modified Steinbrocker scoring method. | 0 |
DIP: distal interphalangeal; PAM: psoriatic arthritis mutilans; CCP: cyclic citrullinated peptide antibodies.