Is the involvement of the distal interphalangeal joint in psoriatic patients related to nail psoriasis?

Abstract

The aim of this study was to investigate the relationship between onychopathy and distal interphalangeal (DIP) joint involvement in psoriatic patients. Twenty-five consecutive unselected, unrelated patients with psoriatic onychopathy and 25 consecutive unselected, unrelated patients with psoriatic arthritis without onychopathy, were enrolled in the study. X-ray films of the hands were taken to identify DIP arthritic involvement and/or bone changes of the distal phalanx, which were categorized into five classes (0: no lesions; 1: tuftal minimal erosions; 2: tuftal bone resorption; 3: tuftal periosteal osteitis; 4: overlap of erosive and osteitic changes). Ten psoriatic patients with onychopathy and 8 without showed DIP arthritis, with no statistical differences in this distribution ( p=0.556). Bone changes of the distal phalanx were found in all 25 psoriatic patients with onychopathy and in 18 without. The distribution of patients in different categories of involvement of the distal phalanx showed that patients without onychopathy were markedly distributed in the categories with no or minimal lesions, whereas patients with onychopathy had structural changes prevailing included in categories with more severe bone changes (osteitis and overlap of erosive and osteitic changes) ( p=0.002). Onychopathic patients with DIP arthritis were older than those without ( p<0.0001) and showed a longer duration of onychopathy ( p<0.0001). Although the occurrence of DIP arthritis seems to depend on the duration of nail involvement, no statistical difference has been found in the distribution of DIP arthritis in psoriatic patients with or without onychopathy. In contrast, a topographical association between bone changes of the distal phalanx and dystrophy of the adjacent nail may be advanced.

Psoriatic nail involvement and its relationship with distal interphalangeal joint disease

“…Scarpa et al revealed the relationship between DIP arthritis and the duration of onychopathy in PsA [16]. However, most of the PsA patients pay little awareness to their nail conditions.…”

“…Plain radiographs of bilateral hands were taken to detect and define PsA bony changes in distal interphalangeal (DIP) joints [14,16]. Radiographs are useful for identifying typical proliferative and destructive bone lesions in PsA [14,16].…”

“…Radiographs are useful for identifying typical proliferative and destructive bone lesions in PsA [14,16]. Four main radiographical findings were described to define DIP arthritis, including (1) normal, (2) erosion only, (3) tuftal periosteal osteitis only and (4) overlap of erosive and osteitic changes [16].…”

Linear Pitting and Splinter Haemorrhages Are More Commonly Seen in the Nails of Patients with Established Psoriasis in Comparison to Psoriatic Arthritis

“…In the latter case, we hypothesised that the involvement of the nail matrix by the inflammatory process might contribute to lesions such as pitting in a linear pattern consistent with the ‘finger-like’ attachment of the ligamentous structures linking the nail to the extensor tendon and distal interphalangeal joint capsule [16]. …”

Patient Assessments of Skin, Joint, and Nail Disease Activity in Psoriatic Arthritis: Table 1.

“…A study by Williamson and colleagues assessed 69 patients with PsA and found correlations between nail disease severity and skin disease, enthesitis, polyarticular disease, HAQ score, higher depression and anxiety scores, and unremitting and progressive arthritis 4 . Scarpa and colleagues found a relationship between distal interphalangeal (DIP) arthritis in patients with PsA and the duration of nail psoriasis, although there was not a statistically significant correlation between the distribution of DIP arthritis and onychopathy 5 .…”