Incidence of osteoperiostitis of the great toe in psoriatic arthritis.

OBJECTIVE

To assess the incidence of osteoperiostitis of the distal phalanx of the great toe in psoriatic arthritis (PsA).

METHODS

One thousand great toes (202 of PsA, 44 of cutaneous psoriasis, 274 of low back pain patients, 296 of rheumatoid arthritis, 136 of spondyloarthropathy, and 48 of connective tissue diseases) were studied for osteoperiostitis of the distal phalanx of the great toe (slight, moderate, or severe), destructive joint lesions of the feet, nail dystrophy, fungal infection, and HLA-B type (patients with PsA).

RESULTS

Osteoperiostitis was observed in 92 great toes. Moderate and severe osteoperiostitis were observed only in PsA. Osteoperiostitis was statistically more frequent in PsA (53/202, 26.2%, especially in those with onychosis: 20/41, 48.8%) than in other groups (39/798, 4.9%) (p < 0.01). In PsA, osteoperiostitis was more frequent in patients with nail dystrophy (20/41, 48.8%) than in patients without (33/161, 20.5%) (p < 0.05). Fungal infection of the nail and HLA haplotype were not associated with osteoperiostitis. In patients with PsA, osteoperiostitis was associated with destructive joint lesions of the feet.

CONCLUSION

Osteoperiostitis of the distal phalanx of the great toe is an enthesopathy evocative of PsA.