Foot involvement in psoriatic arthritis: prevalence, clinical and radiological features

Background The purpose of this study was to evaluate the prevalence of foot involvement in psoriatic arthritis and to describe its different clinical and radiological features. Patients and Methods We conducted a cross sectional study including 40 patients with psoriatic arthritis over a period of 12 months. Anamnesis, clinical examination of feet, podoscopic examination, X-rays of feet and heels, and ultrasound in B mode and power Doppler mode were done for each patient. Results Foot involvement was found in 95% of cases. It was symptomatic in 70% and inaugural of the disease in 20% of cases. The hindfoot and the forefoot were the sites most affected (77.5% and 47.5% respectively). The involvement of the midfoot was rarer (25%). Dactylitis was found in 17.5% and deformities of forefoot were found in 22.5% of cases. Antalgic gait was noted in 17.5% and static disorders of foot at podoscopic examination were identified in 35% of cases. Feet dermatological manifestations were found in 45% of cases. Diagnosis of different rheumatological manifestations was based on clinical findings and caracteristic radiological images on X-rays. We demonstrate he sensitivity of ultrasound in the detection and the diagnosis of different foot lesions including enthesitis, synovitis and tenosynovitis, dactylitis, bone erosions and psoriatic nail dystrophy.